Co-reporter:Jiadi Sun, Xiaoya Liu, Long Meng, Wei Wei, and Yufeng Zheng
Langmuir September 23, 2014 Volume 30(Issue 37) pp:11002-11010
Publication Date(Web):September 23, 2014
DOI:10.1021/la5010177
A novel biomedical coating was prepared from self-assembled colloidal particles through direct electrodeposition. The particles, which are photo-cross-linkable and nanoscaled with a high specific surface area, were obtained via self-assembly of amphiphilic poly(γ-glutamic acid)-g-7-amino-4-methylcoumarin (γ-PGA-g-AMC). The size, morphology, and surface charge of the resulting colloidal particles and their dependence on pH, initial concentrations, and UV irradiation were successfully studied. A nanostructured coating was formed in situ on the surface of magnesium alloys by electrodeposition of colloidal particles. The composition, morphology, and phase of the coating were monitored using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and X-ray diffraction. The corrosion test showed that the formation of the nanostructured coating on magnesium alloys effectively improved their initial anticorrosion properties. More importantly, the corrosion resistance was further enhanced by chemical photo-cross-linking. In addition, the low cytotoxicity of the coated samples was confirmed by MTT assay against NIH-3T3 normal cells. The contribution of our work lies in the creation of a novel strategy to fabricate a biomedical coating in view of the versatility of self-assembled colloidal particles and the controllability of the electrodeposition process. It is believed that our work provides new ideas and reliable data to design novel functional biomedical coatings.
Co-reporter:Chenglin Yi, Jianhua Sun, Donghua Zhao, Qiong Hu, Xiaoya Liu, and Ming Jiang
Langmuir June 17, 2014 Volume 30(Issue 23) pp:6669-6677
Publication Date(Web):May 20, 2014
DOI:10.1021/la500326u
Polymeric micelles could be used as model polymeric particulate emulsifiers to elucidate the correlation between the micellar structure and their emulsifying performance. Photo-cross-linkable and pH-responsive micelles were prepared with amphiphilic random copolymers, poly(7-(4-vinylbenzyloxyl)-4-methylcoumarin-co-acrylic acid) (PVMAA), via the self-assembly in selective-solvent DMF/H2O and then used as polymeric particulate emulsifiers to stabilize toluene-in-water emulsions. Primary micelles, based on PVMAA with 12 mol % of hydrophobic composition, were chosen as model to investigate the influence of photo-cross-linking on the emulsifying performance. The larger shrinkage degree by photo-cross-linking (SDC) the micelles have, the lower emulsifying efficiency the micelles exhibit. Furthermore, the structural transitions of micelles with SDC of 0% and 95% in response to pH change were comparatively confirmed by a combination of electrophoresis, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The micelles of various states, manipulated by photo-cross-linking and pH changes, were used as emulsifiers to stabilize toluene-in-water or styrene-in-water emulsions. For the un-cross-linked micelles, polymer chains gradually protrude from micelles with pH increasing, which benefits the increase in the emulsifying efficiency of micelles. However, as pH elevated over 8, the stability of emulsions significantly decreases due to the disintegration of micelles. On the contrary, micelles with SDC of 95% keep their structural integrity and become more rigid as pH increase, leading to lower emulsifying efficiency of micelles and worse stability of the emulsions. This paper provides a new insight into the principles governing the extremely high emulsifying efficiency of polymeric particulate emulsifiers and pH-dependent or pH-responsive properties of the formed emulsions.
Co-reporter:
Journal of Applied Polymer Science 2017 Volume 134(Issue 26) pp:
Publication Date(Web):2017/07/10
DOI:10.1002/app.44863
ABSTRACTToughening of epoxy resin by block copolymers containing an epoxy-philic block and an epoxy-phobic block is usually costly because of their complex preparation procedure. In this work, a novel, random epoxy-amphiphilic copolymer (PHGEL), which combines an “epoxy-philic” component and an “epoxy-phobic” component, has been synthesized and evaluated as a potential toughening agent for a diglycidyl ether of bisphenol A–based epoxy thermoset (EP). The curing behavior of the EP/PHGEL system has been investigated, and the results show that the hydroxyl group on the PHGEL chain can slightly activate the curing reaction. The mechanical testing shows that the toughness of the epoxy resin is improved by 294% when 4 wt % of PHGEL is added. Simultaneously, the tensile strength, elongation at break, and glass-transition temperature are also improved. In addition, the thermogravimetric analysis shows that PHGEL has no obvious effect on the thermal stability of the epoxy thermosets. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44863.
Co-reporter:Xiaoma Fei, Wei Wei, Fangqiao Zhao, Ye Zhu, Jing Luo, Mingqing Chen, and Xiaoya Liu
ACS Sustainable Chemistry & Engineering 2017 Volume 5(Issue 1) pp:
Publication Date(Web):October 24, 2016
DOI:10.1021/acssuschemeng.6b01967
Research into toughening an epoxy resin using biobased modifiers without trade-offs in its modulus, mechanical strength, and other properties still remains a challenge. In this article, an approach to toughen epoxy resin with tannic acid, a common polyphenolic compound extracted from plants and microorganisms, is presented. First, dodecane functionalized tannic acid (TA-DD) is prepared and subsequently incorporated into epoxy/anhydride curing system. Owing to the modification of long aliphatic chain, TA-DD can induce epoxy matrix yielding phase separation, forming microscaled separated phases. In the meantime, the terminal hydroxyl groups of TA-DD can participate in the curing process, which offers a good interfacial interaction between TA-DD and epoxy matrix. With such a mechanism, the results show that TA-DD can significantly toughen the epoxy resin without trade-offs in its strength, modulus, and Tg. The thermoset with only 0.5 wt % TA-DD reaches highest impact strength, which is 196% increase of that of neat epoxy. This article opens up the possibility of utilizing the renewable tannic acid as an effective modifier for epoxy resin with good mechanical and thermal properties.Keywords: Biobased; Epoxy toughener; Hyperbranched; Tannic acid;
Co-reporter:Hu Li;Zhen Zhou;Jingcheng Liu;Wenjia Xu;Ren Liu
Polymer Bulletin 2017 Volume 74( Issue 4) pp:1091-1101
Publication Date(Web):2017 April
DOI:10.1007/s00289-016-1765-5
Positive chemically amplified molecular glass with pendant t-butyloxy carbonyl (t-BOC) groups based on β-cyclodextrin (β-CD) was prepared. The β-CD derivatives were obtained from the reaction of β-CD and di-tert-butyl dicarbonate (DBDC) in the presence of 4-dimethylaminopyridine, and the protecting ratio was controlled using various feed amounts of DBDC. Fourier-transform infrared spectroscopy and proton nuclear magnetic resonance were employed to characterize the chemical structure, indicating that the synthesis was successful. Thermal behavior was characterized by thermogravimetric analysis; the results showed that the initial thermal decomposition temperature occurred at approximately 160 °C, which could satisfy the lithography process. Ultraviolet–visible spectrophotometer indicated that the t-BOC-protected β-CD derivatives had low absorbance at 365 nm wavelength. Additionally, X-ray diffraction analysis results showed that the β-CD derivatives had amorphous form, and exhibited excellent film-forming property. The photoresists consisting of different t-BOC protecting groups showed high sensitivity when exposed to 365 nm light and post-baked at 105 °C for 90 s, followed by developing in 2.38 wt% aqueous tetramethylammonium hydroxide solution at room temperature. An enhanced line and space positive patterns with 1 μm resolution were delineated according to digital microscope.
Co-reporter:Jing Luo, Qiang Ma, Wei Wei, Ye Zhu, Ren Liu, and Xiaoya Liu
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 32) pp:21028
Publication Date(Web):July 27, 2016
DOI:10.1021/acsami.6b05440
A novel kind of water-dispersible molecularly imprinted electroactive nanoparticles was prepared combining macromolecular self-assembly with molecularly imprinting technique employing paracetamol (PCM) as template molecule. An amphiphilic electroactive copolymer (P(NVC-EHA-AA), PNEA) containing carbazole group was first synthesized through a one-pot free radical copolymerization. The coassembly of the electroactive copolymers with the template molecules (PCM) in aqueous solution generated nanoparticles embedded with PCM, leading to the formation of molecularly imprinted electroactive nanoparticles (MIENPs). A robust MIP film was formed on the surface of electrode by electrodeposition of MIENPs and subsequent electropolymerization of the carbazole units in MIENPs. After the extraction of PCM molecules, a MIP sensor was successfully constructed. It should be noted that electropolymerization of the electroactive units in MIENPs creates cross-conjugated polymer network, which not only locks the recognition sites but also significantly accelerates the electron transfer and thus enhances the response signal of the MIP sensor. These advantages endowed the MIP sensor with good selectivity and high sensitivity for PCM detection. The MIP sensor could recognize PCM from its possible interfering substances with good selectivity. Under the optimal conditions, two linear ranges from 1 μM to 0.1 mM and 0.1 to 10 mM with a detection limit of 0.3 μM were obtained for PCM detection. The MIP sensor also showed good stability and repeatability, which has been successfully used to analyze PCM in tablets and human urine samples with satisfactory results.Keywords: electroactive nanoparticle; electropolymerization; macromolecular assembly; MIP sensor; molecular imprinting
Co-reporter:Jiadi Sun, Ye Zhu, Long Meng, Peng Chen, Tiantian Shi, Xiaoya Liu, Yufeng Zheng
Acta Biomaterialia 2016 Volume 45() pp:387-398
Publication Date(Web):November 2016
DOI:10.1016/j.actbio.2016.09.007
Abstract
Magnesium (Mg) has recently received increasing attention due to its unique biological performance, including cytocompatibility, antibacterial and biodegradable properties. However, rapid corrosion in physiological environment and potential toxicity limits its clinical applications. To improve the corrosion resistance meanwhile not compromise other excellent performance, self-assembled colloidal particles were deposited onto magnesium surfaces in ethanol by a simple and effective electrophoretic deposition (EPD) method. The fabricated functional nanostructured coatings were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) analyses, and scanning electron microscopy (SEM). The electrochemical test, pH value, and Mg ion concentration data show that the corrosion resistance of Mg samples is enhanced appreciably after surface treatment. In vitro cellular response and antibacterial capability of the modified Mg substrates are performed. Significantly increased cell adhesion and viability are observed from the coated Mg samples, and the amounts of adherent bacteria on the treated Mg surfaces diminish remarkably compared to the bare Mg. Furthermore, the bare and coated Mg samples were implanted in New Zealand white rabbits for 12 weeks to examine the in vivo long-term corrosion performance and in situ inflammation behavior. The experiment results confirmed that compared with bare Mg substrate the corrosion and foreign-body reactions of the coated Mg samples were suppressed. The above results suggested that our coatings, which effectively enhance the biocompatibility, antimicrobial properties, and corrosion resistance of Mg substrate, provide a simple and practical strategy to expedite clinical acceptance of biodegradableMg and its alloys.
Statement of Significance
Biomedical Mg metals have been considered as promising biodegradable implants because of their intended functions, such as cytocompatibility, antibacterial, and biodegradable properties. However, rapid corrosion in physiological environment limits their clinical applications. Alloying and surface coatings have been used to reduce the degradation rate. But this would compromise other excellent performance of Mg samples, including antibacterial and anti-inflammatory activity. Thus, while the rapid degradation of Mg samples must be solved, good antibacterial property and acceptable cytocompatibility are also necessary. In this study, polymer-based coatings were fabricated on Mg surfaces by electrophoretic deposition of poly(isobornyl acrylate-co-dimethylaminoethyl methacrylate)/tannic acid (P(ISA-co-DMA)/TA) colloidal particles. It suggested that the coating materials effectively improved the biocompatibility, antimicrobial behavior, and corrosion resistance of biomedical Mg.
Co-reporter:Yan Yuan, Yulin Zhang, Ren Liu, Jingcheng Liu, Zhiquan Li and Xiaoya Liu
RSC Advances 2016 vol. 6(Issue 53) pp:47498-47508
Publication Date(Web):09 May 2016
DOI:10.1039/C6RA03050E
In this study, 7-(4-vinylbenzyloxyl)-4-methylcoumarin (VM) and maleic anhydride (MA) were polymerized through free radical copolymerization to form a photosensitive alternating copolymer P(VM-alt-MA) (PVMA). PVMA was used as a soft template to achieve the oxidative polymerization of poly(3,4-ethylenedioxythiophene) (PEDOT). We obtained a stable PEDOT:PVMA photosensitive aqueous dispersion with an average diameter in the range of 140 to 210 nm. We then used this aqueous dispersion as the ink for fabricating humidity sensors through inkjet-printing on a paper substrate. The printed photosensitive conductive film PEDOT:PVMA could be cross-linked after photo-dimerisation of coumarin groups, leading to a small decrease of electrical conductivity, but also appreciable improvements in water resistance and sensor robustness. The humidity sensing ability of these PEDOT:PVMA/paper sensors was investigated by exposing them to a wide range of relative humidity, namely 11–97% at room temperature. These paper sensors could selectively and reversibly detect water vapor with a significant linear relationship. The response strength and the response/recovery time of the sensors show a substantial improvement compared with those of previous reports. The photo-dimerisation of PEDOT:PVMA improves the stability of humidity response and the response/recovery time of the sensors.
Co-reporter:Cuige Zhang, Rongli Zhang, Ye Zhu, Wei Wei, Yao Gu, Xiaoya Liu
Materials Letters 2016 Volume 164() pp:15-18
Publication Date(Web):1 February 2016
DOI:10.1016/j.matlet.2015.10.052
•Preparation of amphiphilic l-phenylalanine ethyl ester-modified hyaluronic acid.•Self-assembly of amphiphilic polymer into vesicles.•The size and wall thickness of the vesicles depend on the modification degree.In recent years, polymer vesicles prepared by self-assembly techniques have attracted increasing scientific interest because of their numerous extensive applications in drug release, nano-reactors and catalysis. In this work, hyaluronic acid (HA) was hydrophobically modified by l-phenylalanine ethyl ester (l-Phe) via amidation reaction between the carboxylic group of HA and the amine group of l-Phe. The amphiphilic polymers could self-assemble into nanoparticles of vesicle structure. The size and wall thickness of the vesicles were dependent on the modification degree of l-Phe. The results showed that with the increase of the modification degree of l-Phe, the size of the vesicles gradually decreased and the wall thickness of the vesicles gradually increased. Morphologies of the vesicles were characterized by transmission electron microscopy (TEM), scanning electron microscope (SEM) and atomic force microscope (AFM).
Co-reporter:Xiaoqing Dong;Weizhen Shen;Peng Hu;Zhiquan Li;Ren Liu
Journal of Applied Polymer Science 2016 Volume 133( Issue 13) pp:
Publication Date(Web):
DOI:10.1002/app.43239
ABSTRACT
The narrow emission spectra of light emitting diodides (LED) as irradiation source has brought great challenge for the development of efficient photoinitiators sensitive to LED light. This paper described a series of novel unimolecular type II photoinitiators, containing thioxanthones as chromophores and benzodioxoles as coinitiators. The structures of the photoinitiators were characterized by 1H NMR, 13C NMR and high-resolution mass spectrometer. Study on the photophysical properties of the photoinitiators indicated that electron donors/acceptors as spacers between thioxanthone and benzodioxole affected both the UV–Vis absorption and the fluorescence emission. The long wavelength absorptions from 385 nm to 402 nm as well as low fluorescence quantum yields make the investigated benzodioxole derivatives quite attractive as efficient photoinitiators under UV-A and visible LED light irradiation. With a proper molecular design, the unimolecular photoinitiator exhibited higher initiation efficiency than the thioxanthone derivatives from the literature. Possible initiation mechanism was also proposed based on the photolysis study. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43239.
Co-reporter:Hu Li;Jingcheng Liu;Xiangfei Zheng;Changwei Ji;Qidao Mu;Ren Liu
Journal of Applied Polymer Science 2016 Volume 133( Issue 3) pp:
Publication Date(Web):
DOI:10.1002/app.42838
ABSTRACT
Novel branched copolymers, poly(styrene-alt-maleic anhydride) (BPSMA), were synthesized through mercapto chain-transfer polymerization with styrene, maleic anhydride (MA), and 4-vinyl benzyl thiol (VBT). Then, the hydroxyl of hydroxyethyl methacrylate was reacted with MA to synthesize branched photosensitive copolymers, p-BPSMAs. Fourier transform IR spectroscopy and 1H-NMR indicated that the synthesis was successful. Gel permeation chromatography indicated that the molecular weight decreased with increasing content of VBT. The thermal properties were characterized by thermogravimetric analysis; the results show that the thermal decomposition temperature of the BPSMAs was greatly enhanced. Real-time IR was used to evaluate the UV-curable kinetics of the p-BPSMAs; the results show that the p-BPSMAs could rapidly photopolymerize under UV irradiation in the presence of photoinitiators. Moreover, the photoresist based on the p-BPSMAs exhibited improved photosensitivity when the VBT content increased, and the photoresist with 12 mol % VBT content had a low value of the dose that retained 50% of the original film thickness (10 mJ/cm2), and a 50-μm resolution could be achieved compared to a linear photoresist. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 42838.
Co-reporter:Hu Li;Jingcheng Liu;Xiangfei Zheng;Changwei Ji;Qidao Mu
Journal of Polymer Research 2016 Volume 23( Issue 5) pp:
Publication Date(Web):2016 May
DOI:10.1007/s10965-016-0996-3
KrF photoresist polymers (PASTMs) were prepared via reversible addition-fragmentation chain transfer (RAFT) polymerization. Four (meth)acrylates with lithographic functionalities including styrene (St), 4-acetoxystyrene (AST), 2-methyl-2-adamantyl methacrylate (MAMA), and tert-butyl acrylate(TBA) were used as monomer components and 2-methyl-2-[(dodecylsulfanylthiocarbonyl) sulfanyl]propanoic acid (MDFC) was used as RAFT agent, varying the RAFT content could modulate molecular weight. Fourier-transform infrared spectroscopy (FT-IR) and proton nuclear magnetic resonance (1H NMR) indicated that the synthesis was successful. Gel permeation chromatography (GPC) showed that the molecular weight decreased with the increased content of MDFC, and all the polymers possessed weight-average molecular weight below ten thousand and polydispersity less than 1.32. Thermogravimetric analysis (TGA) characterized the thermal properties, the results implied that initial thermal decomposition temperature reached 200 °C, which could satisfy the lithography process. Differential scanning calorimetry (DSC) showed that the Tg decreases with molecular weight. The RAFT polymerization kinetics plots demonstrated that the polymerization was first-order, the number-average molecular weights of the polymers with relatively low polydispersity index values increased with total monomer conversions indicating that the concentration of growing radicals was constant throughout the polymerization process. The narrow molecular weight distribution and composition uniformity of the polymers prepared by RAFT polymerization could be beneficial for lithography, after alcoholysis, lithography evaluation under KrF lithography showed that this homogeneous polymer photoresist exhibited better space and line (S/L) pattern with resolution of 0.18 μm according to the SEM image.
Co-reporter:Ren Liu;Xuebiao Zeng;Jingcheng Liu;Jing Luo;Yuanyi Zheng
Microchimica Acta 2016 Volume 183( Issue 5) pp:1543-1551
Publication Date(Web):2016 May
DOI:10.1007/s00604-016-1763-1
The article describes an electrochemical sensor for simultaneous determination of dopamine (DA) and paracetamol (PAT). It is based on the use of an electroactive polymer (referred to as BPVCM) to functionalize multi-walled carbon nanotubes. BPVCM is a branched amphiphilic photo-sensitive and electroactive polymer that was obtained by copolymerization of a vinyl benzylcarbazole, maleic acid anhydride, 4-vinylbenzylthiol and a vinylbenzyloxycoumarin. BPVCM efficiently disperses MWCNT in aqueous solution. The electropolymerization of the carbazole moieties of the BPVCM enhances the current response. It also facilitates electron transfer in the MWCNT-BPVCM hybrid as evidenced by cyclic voltammetry and electrochemical impedance spectroscopy. A glassy carbon electrode modified with the nanocomposite displays outstanding electrocatalytic activity towards DA and PAT. DA can be determined, best at a working voltage of 0.2 V (vs. SCE), in the 5 to 1000 μM concentration range with a 2.3 μM detection limit. PAT can be determined in parallel, at a working voltage of 0.39 V (vs. SCE), in the same concentration range with a 3.5 μM detection limit. This analytical range of this method is wider than that of most alternative methods.
Co-reporter:Ye Zhu, Qiong Hu, Wei Wei, Chenglin Yi, Xiaoya Liu
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2016 Volume 504() pp:358-366
Publication Date(Web):5 September 2016
DOI:10.1016/j.colsurfa.2016.05.099
•A novel pH-responsive colloidal particles PAS-Poly(DVB) were directly prepared by RAFT-mediated cross-linking copolymerization.•The colloidal particles can be used as effective polymeric particulate emulsifiers.•A structural transition plays an important role in the emulsification performance of these colloidal particles.•The oil-in-water high internal phase emulsions (HIPEs) could be stabilized by flocculated colloidal particles, and the HIPEs showed pH-responsiveness.In this study a type of colloidal particles with a cross-linked poly(divinylbenzene) (poly(DVB)) core and a poly(acrylic acid-r-styrene) (PAS) shell were directly prepared by reversible addition-fragmentation chain transfer (RAFT)-mediated cross-linking copolymerization. The particle size, morphology, zeta potential and pH responsibility were studied. The emulsification study showed that PAS-Poly(DVB) colloidal particles were effective particulate emulsifiers when homogenized with various oils including toluene, white oil, isooctyl palmitate, dicaprylyl carbonate, silicone oil, and propylheptyl caprylate. Additionally, the emulsification performance of PAS-Poly(DVB) colloidal particles at different pH values were investigated. Gelled white oil-in-water high internal phase emulsions (HIPEs) were formed at a high oil volume fraction of 80% when the colloidal particles were flocculated at low pH value. The addition of base can trigger the demulsification of the HIPEs, exhibiting a pH-responsive behavior. The effects of oil phase volume fraction on emulsion rheological properties were investigated. Both the emulsion viscosity and storage modulus (G′) progressively increased with the increasing of oil phase volume fraction. These results suggest that our work provides a convenient and feasible way to prepare effective particulate emulsifiers via the direct chemical reaction, and the PAS-Poly(DVB) colloidal particles have promising potential application in the oil industry and preparation and exploitation of smart materials.A new type of spherical-like colloidal particles with a cross-linked poly(DVB) core and a poly (acrylic acid-r-styrene) (PAS) shell were prepared and utilized as effective particulate emulsifiers to stablize oil-in-water emulsions.
Co-reporter:Wei Wei, Rongjie Lu, Weitao Ye, Jianhua Sun, Ye Zhu, Jing Luo, and Xiaoya Liu
Langmuir 2016 Volume 32(Issue 7) pp:1707-1715
Publication Date(Web):January 30, 2016
DOI:10.1021/acs.langmuir.5b04697
Increasing attention has been paid to fabricate multifunctional stabilizers of liquid marbles for expanding their application. Here, a kind of hydrophobic cyclomatrix polyphosphazene particles (PZAF) were facilely prepared using a one-step precipitation polycondensation of hexachlorocyclotriphosphazene and 4,4′-(hexafluoroisopropylidene)diphenol, and their ability to stabilize liquid marbles was first investigated. The Ag nanoparticle-decorated PZAF particles (Ag/PZAF) were then fabricated by an in situ reduction of silver nitrate onto PZAF particles and used to construct catalytic liquid marbles. The results revealed that the reduction of methylene blue (MB) in aqueous solution by sodium borohydride could be highly efficiently catalyzed in the catalytic liquid marbles, even with a large volume. An excellent cycle use performance of the catalytic liquid marbles without losing catalytic efficiency was also present. The high catalytic activity is mainly attributed to the uniform immobilization of Ag nanoparticles onto PZAF particles and the adsorption behavior of PZAF particles toward MB, which may play an effect on allowing high catalytic surface area and effective accelerating the mass transfer of MB to the Ag catalytic active sites, respectively. Therefore, the combination of Ag nanoparticles with PZAF particles has been demonstrated clearly to be a facile and effective strategy to obtain the functional stabilizer for preparing the catalytic liquid marbles as promising miniature reactors used in heterogeneous catalytic reactions.
Co-reporter:Wei Wei, Rongjie Lu, Shuyuan Tang and Xiaoya Liu
Journal of Materials Chemistry A 2015 vol. 3(Issue 8) pp:4604-4611
Publication Date(Web):12 Jan 2015
DOI:10.1039/C4TA06828A
Highly cross-linked and organic–inorganic hybrid poly(cyclotriphosphazene-co-curcumin) microspheres (PCPC-MS) were facilely prepared by a one-step precipitation copolymerization method, and served as a fluorescent chemical sensor for the detection of picric acid (PA) in solution phase. The photochemically inert cyclotriphosphazene moieties intentionally introduced into the structure of the sensor could play a role not only in connecting curcumin fluorophores to construct a highly cross-linked fluorescent architecture with excellent thermal stability and photobleaching stability, but also in effectively enriching PA from bulk solution to the surface of the sensor by the acid–base interaction between the acidic phenolic hydroxyl groups of PA molecules and the electron-rich nitrogen atoms of the cyclotriphosphazene units, which might facilitate the formation of a ground-state non-fluorescent complex of the microspheres and PA as well as the excited-state energy transfer from the microspheres to PA. Therefore, PCPC-MS exhibited a fluorescence quenching response towards PA with high sensitivity, efficiency, and selectivity over a number of other analytes such as 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, 1,3-dinitrobenzene, 4-nitrotoluene, nitrobenzene, 4-benzoquinone, chlorobenzene, and nitromethane in methanol. In addition, PCPC-MS could also effectively detect PA in the presence of the other analytes, indicating their remarkable ability for resisting interferences and specific recognition of PA. This study provides new insights into the design and preparation of a polymer-based fluorescence chemical sensor for PA with low toxicity, a simple preparation process, and high selectivity.
Co-reporter:Jiadi Sun, Ye Zhu, Long Meng, Wei Wei, Yang Li, Xiaoya Liu and Yufeng Zheng
Journal of Materials Chemistry A 2015 vol. 3(Issue 8) pp:1667-1676
Publication Date(Web):02 Jan 2015
DOI:10.1039/C4TB01683A
We report a potential example of using surface functionalization to provide magnesium alloys (Mg–Ca) with controlled release and corrosion resistance properties. A key feature of this approach is to treat the Mg–Ca surfaces with nanoparticles via electrodeposition that can stably load and controllably release bioactive agents or drugs. These photo-cross-linkable and nano-scale particles were prepared by the self-assembly of an amphiphilic poly(γ-glutamic acid)-g-7-amino-4-methylcoumarin (γ-PGA-g-AMC) with encapsulation of a vitamin; moreover, the size and morphology of the resulting particles were studied. Fluorescence microscopy analysis indicated that Vm was effectively incorporated into the γ-PGA-g-AMC particles. Scanning electron microscopy (SEM) images showed that the colloidal particles could be uniformly electrodeposited on the Mg–Ca alloys. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses confirmed the successful anchoring of the particles. After the surface electrodeposition of self-assembled colloidal particles, the in vitro degradation results show that deposition of the particles was found to reduce the degradation rate of the magnesium alloys; moreover, the vitamin was controllably released for up to 20 days. Furthermore, the Mg–Ca substrate functionalized with colloidal particles containing a vitamin significantly promoted the attachment, proliferation and spread of NIH-3T3 normal cells. The entire strategy may be used in various medical devices to create coatings for improved biomedical performance.
Co-reporter:Wei Wei, Rongjie Lu, Haojie Xie, Yifan Zhang, Xue Bai, Li Gu, Rui Da and Xiaoya Liu
Journal of Materials Chemistry A 2015 vol. 3(Issue 8) pp:4314-4322
Publication Date(Web):02 Jan 2015
DOI:10.1039/C4TA06444E
Nitrogen-enriched and organic–inorganic hybrid polymer submicro-spheres based on highly cross-linked poly(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS) were prepared using one-step precipitation copolymerization route. The chemical structure and morphology of the submicro-spheres were characterized. The adsorption behaviors of the submicro-spheres towards different organic dyes in an aqueous solution were investigated systematically. The results showed that PZS submicro-spheres could effectively adsorb methylene blue (MB), Bismarck brown Y (BY), neutral red (NR), rhodamine B (RhB), and calcein (Cal) with high adsorption capacities, but they could hardly adsorb orange G (OG), Ponceau S (PS), and methyl orange (MO), indicating that PZS submicro-spheres could adsorb guest dyes selectively. The adsorption process was found to follow the pseudo-second-order kinetic model rather than the pseudo-first-order one. Isotherm studies revealed that the Langmuir model was more suitable for describing the adsorption behavior of the PZS submicro-spheres than the Freundlich model. A probable mechanism based on the unique host–guest interactions between the submicro-spheres and the dyes was proposed and experimentally verified to explain the selective adsorption. The nitrogen-enriched PZS submicro-spheres possess electron-donating and proton-attracting abilities and could act as bases, and thus the dyes that are classified as Lewis acids (electron acceptor) and/or Brønsted acids (proton donor) could be selectively adsorbed onto the submicro-spheres by acid–base interactions. Because of the selective adsorption behavior towards different organic dyes, PZS submicro-spheres also exhibited a strong ability for separating dye mixtures in an aqueous solution.
Co-reporter:Ren Liu, Xiaopeng Zhang, Jiajia Zhu, Xiaoya Liu, Zhen Wang, and Jingling Yan
ACS Sustainable Chemistry & Engineering 2015 Volume 3(Issue 7) pp:1313
Publication Date(Web):June 10, 2015
DOI:10.1021/acssuschemeng.5b00029
Multiarmed, cardanol-based acrylate oligomers were prepared via the ring-opening reaction between cardanyl glycidyl ether (CGE) and polyacids, followed by epoxidization of the unsaturation in alkyl side chains of cardanol segments, and acrylation of the resulting epoxy groups. Biobased coatings were produced from UV-radiation-initiated curing of these acrylates; the coating properties were then characterized in detail. The acrylate oligomers were fully characterized using gel permeation chromatography (GPC), Fourier transform infrared spectroscopy (FTIR), and proton nuclear magnetic resonance (1H NMR). The UV-curing behavior of these acrylates was determined using real-time IR. The results indicated that the conversion of acrylate unsaturation increased with increasing oligomer functionality. These oligomers were formulated into UV-curable coatings, and the coating properties were evaluated to determine hardness, adhesion, chemical resistance, gloss, and surface properties. The properties of cured thermosets were also studied using tensile testing, dynamic mechanical thermal analysis (DMTA), and thermogravimetric analysis (TGA). Compared to coating from benchmark biobased UV-curable oligomer, acrylated epoxidized soybean oil (ASBO), cardanol-based coatings showed higher hardness, excellent adhesion, and enhanced thermal and mechanical properties while maintaining reasonably high biorenewable contents. These improvements in coating performances can be contributed to their unique oligomer architectures that combined the structural features of rigid benzene ring, long flexible alkyl chains, and polar hydroxyl groups.Keywords: Biobased; Cardanyl glycidyl ether; Multiarmed acrylate oligomers; UV-curable coatings
Co-reporter:Cuige Zhang, Suhan Yang, Ye Zhu, Rongli Zhang, Xiaoya Liu
Carbohydrate Polymers 2015 Volume 133() pp:637-643
Publication Date(Web):20 November 2015
DOI:10.1016/j.carbpol.2015.07.035
•Preparation of amphiphilic cinnamic acid-modified dextran.•Self-assembly of cinnamic acid-modified dextran into bowl-shaped nanoparticle.•The modification degree of cinnamic acid has important effect on the size of the dimples.•The size of the dimples depends on concentration of cinnamic acid-modified dextran.•The size of the dimples can be controlled by changing the rate of water addition.The self-assembly of amphiphilic copolymers has attracted much attention because of their various morphologies and potential applications. Bowl-shaped nanoparticles could apply in many aspects due to their interior cavity, specific concave structure and high surface area. In this study, dextran (Dex) was hydrophobic modified by cinnamic acid (CINN) via esterification reaction between the hydroxyl group of Dex and the carboxyl group of CINN. The modification degree of CINN could be achieved by changing the feed ratios between Dex, CINN and the coupling agent. The cinnamic acid-modified dextran (Dex–CINN) composed of Dex as hydrophilic segment and CINN as hydrophobic segment could self-assemble into bowl-shaped nanoparticles with a single dimple on the surface. Furthermore, the size of the dimples could be controlled by changing the modification degree of CINN, concentration of Dex–CINN and the rate of water addition. The morphologies of bowl-shaped nanoparticles were characterized by transmission electron microscopy (TEM) and scanning electron microscope (SEM).
Co-reporter:Jianhua Sun, Wei Wei, Donghua Zhao, Qiong Hu and Xiaoya Liu
Soft Matter 2015 vol. 11(Issue 10) pp:1954-1961
Publication Date(Web):07 Jan 2015
DOI:10.1039/C4SM02832E
In this study, we report the assembly of amphiphilic polymeric micelles at the liquid/air interface to prepare liquid marbles for the first time. The polymeric micelles were synthesized from the self-assembly of a fluoropolymer, poly(styrene-co-acrylic acid-co-2,2,3,4,4,4-hexafluorobutyl methacrylate), in a selective solvent. The particle size, morphology and chemical composition of the micelles were determined by dynamic light scattering (DLS), transmission electron microscopy, scanning electron microscopy and X-ray photoelectron spectroscopy. DLS and aqueous electrophoresis revealed the pH-responsiveness of the micelles in aqueous dispersion. Liquid marbles with water volumes varying from 10 μL to 1 mL were formed by rolling water droplets on the micelle powder bed. The increase in water volume led to the shape transition of the liquid marbles from quasi-spherical to a puddle-like shape because of gravity. Fluorescence microscopy was used to observe the morphology of the formed liquid marbles, which confirmed that the micelles were adsorbed at the interface of water and air. The effective surface tension of the liquid marbles decreased with the increasing concentration of NaOH, which was added to the interior water phase. This agreed with the results of droplet roller experiments: the mechanical integrity of the liquid marbles prepared from alkaline solution (pH 10) was relatively poorer than those prepared from acidic solution (pH 2). Moreover, these liquid marbles coated with micelles showed pH-responsiveness when transferred onto the surfaces of aqueous solutions with different pH values. The liquid marbles were relatively stable on the acidic solution, whereas they burst immediately on the alkaline solution with a pH of 10. In addition, apart from water, Gellan gum solution and glycerol could be also successfully encapsulated by the fluorinated micelles to form stable liquid marbles.
Co-reporter:Donghua Zhao;Wei Wei;Ye Zhu;Jianhua Sun;Qiong Hu
Macromolecular Bioscience 2015 Volume 15( Issue 4) pp:558-567
Publication Date(Web):
DOI:10.1002/mabi.201400486
A simple, green and effective process is developed to fabricate hyaluronic acid (HA)/chitosan (CS) complex colloidal particles through electrostatic interactions. The obtained complexes can be used as biocompatible emulsifiers and novel potential carriers for papain loading. An HA/CS mass ratio of 2 is the optimal condition leading to the smallest Dh (420.9 nm). The complexes with eight different mass ratios are used to stabilize white oil/water emulsions. The structure of the complexes at the oil—water interface varies in response to the mass ratio and can be classified into two typical structures, similar to typical polymeric surfactants and solid particulate emulsifiers. Furthermore, papain is introduced into the complex systems. Formation of the papain/HA/CS complexes in a compact form can protect the enzyme. Here, a novel strategy is introduced to fabricate a biocompatible emulsion from the HA/CS complexes and demonstrate that the stable complex is a suitable enzyme delivery system.
Co-reporter:Ye Zhu, Juanqin Wang, Xiaojie Li, Donghua Zhao, Jianhua Sun, Xiaoya Liu
Carbohydrate Polymers 2015 Volume 123() pp:72-79
Publication Date(Web):5 June 2015
DOI:10.1016/j.carbpol.2015.01.030
•Dopamine modified hyaluronan (HA-DOPA) with different grafting degree were prepared and self-assembled into nanoparticles.•HA-DOPA nanoparticles can be used as sole emulsifiers for Pickering emulsions.•The structural transitions of HA-DOPA nanoparticles in response to pH and salinity changes could affect the emulsifying performance of the HA-DOPA nanoparticles.Dopamine modified hyaluronan (HA-DOPA) with different grafting degree were synthesized and self-assembled into nanoparticles. The effects of pH and salinity changes on the structure of the HA-DOPA nanoparticles were investigated. Nanoparticles swelled under increased pH values, and disassociation started at pH values above 6.20. At a fixed pH of 6.20, the size of the nanoparticles decreased with increased salinity, and flocculation occurred when the salt concentration was higher than 0.3 M. The emulsification performance of HA-DOPA nanoparticles at different pH values and salt concentrations demonstrated that nanoparticles with moderately swollen structures possess better emulsifying efficiency and emulsion stability. Additionally, HA-DOPA nanoparticles were able to stabilize various types of oils. These results suggest that HA-DOPA nanoparticles have promising potential as Pickering emulsifiers for applications in the cosmetics, medical, and food industries.
Co-reporter:Xiaoqing Dong, Peng Hu, Guigang Zhu, Zhiquan Li, Ren Liu and Xiaoya Liu
RSC Advances 2015 vol. 5(Issue 66) pp:53342-53348
Publication Date(Web):10 Jun 2015
DOI:10.1039/C5RA09314G
A series of photobase generators (PBGs), which contain thioxanthone as the chromophore and different quaternary ammonium salts as latent active species, were straightforwardly synthesized in two steps and their structures were characterized. Investigation on the photophysical properties of the PBGs indicated that the PBGs were photosensitive to long wavelengths due to the characteristic absorption of thioxanthone at 380 nm. A study on photolysis confirmed the photoinduced decarboxylation mechanism, through which the PBGs released active basic species efficiently. All the novel PBGs showed high activity in catalysing thiol–epoxy polymerization without postexposure baking. This is especially true for the PBG containing 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), which exhibited a faster polymerization rate and higher epoxy conversion than the previously described highly active PBG system.
Co-reporter:Wei Wei, Ting Wang, Chenglin Yi, Jingcheng Liu and Xiaoya Liu
RSC Advances 2015 vol. 5(Issue 2) pp:1564-1570
Publication Date(Web):13 Nov 2014
DOI:10.1039/C4RA12100G
Branched copolymer self-assembled micelles, based on amphiphilic branched poly(styrene-alt-maleic anhydride) (BPSMA) synthesized by a one-pot method, are prepared and employed as particulate emulsifiers to stabilize the white oil-in-water Pickering emulsions. The influences of micelle concentration, branching degree, salinity, and oil type on the emulsifying performance of self-assembled micelles are comprehensively investigated, and the distinction between BPSMA micelles and linear poly(styrene-alt-maleic anhydride) (LPSMA) self-assembled micelles on the micellar structure and emulsifying performance is also studied. The results show that the branched structure of the copolymer plays an important role in emulsification. The emulsifying performance of BPSMA micelles is superior to that of LPSMA micelles, reflected in the emulsifying efficiency and the long-term stability of emulsions. It is attributed to the much better structural stability of BPSMA micelles compared to LPSMA micelles, which is probably due to the postponing of hydrolyzing of maleic anhydride and ionization of carboxyl to some extent caused by the introduction of the branched structure in copolymers. It is also worth noting that, salinity has a great effect on the emulsifying performance of LPSMA micelles, but little impact on that of BPSMA micelles. Additionally, BPSMA micelles can also well stabilize the oil-in-water emulsions with some other types of natural oils. Thus the findings are not only of theoretical interest but also of great practical application in the cosmetics area.
Co-reporter:Cuige Zhang, Ye Zhu, Rongli Zhang, Yanling Xie, Kangjing Wang and Xiaoya Liu
RSC Advances 2015 vol. 5(Issue 110) pp:90651-90658
Publication Date(Web):12 Oct 2015
DOI:10.1039/C5RA10737G
Novel bio-based composite nanoparticles were prepared through the electrostatic interaction between lysozyme (Lys) and amphiphilic dopamine-modified poly (γ-glutamic acid) (PGA-DA). The composite nanoparticles were used as particulate emulsifiers to stabilize white oil, forming gel-like emulsions. When the concentration of PGA-DA and Lys was 0.75 mg mL−1, the mean diameter of the composite nanoparticles was smallest (423 nm) with excellent stability. The influences of pH values on the properties of the composite nanoparticles, emulsifying performances and the activity of Lys in the emulsions were carefully investigated. Scanning electron microscopy (SEM) and laser scanning confocal microscopy (CLSM) characterization demonstrated that the composite nanoparticles adsorbed at the oil–water interface. Rheological measurements provided a possible stabilizing mechanism, which depended on the network structure of the adsorption layer at the interface-phase. Emulsifying properties were significantly improved with increasing the pH value of the solution. In addition, the bioactivity of emulsions at pH 6.2 was highest and well retained during a storage period of three months.
Co-reporter:Jiadi Sun;Ye Zhu;Long Meng;Tiantian Shi;Yufeng Zheng
Macromolecular Chemistry and Physics 2015 Volume 216( Issue 19) pp:1952-1962
Publication Date(Web):
DOI:10.1002/macp.201500214
Co-reporter:Rongli Zhang, Ling Lin, Sheng Xu, Cuige Zhang, Xiaoya Liu, Jing Luo
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2015 470() pp: 218-223
Publication Date(Web):
DOI:10.1016/j.colsurfa.2015.01.043
Co-reporter:Rongli Zhang;Sheng Xu;Jing Luo
Microchimica Acta 2015 Volume 182( Issue 1-2) pp:175-183
Publication Date(Web):2015 January
DOI:10.1007/s00604-014-1315-5
A voltammetric sensor for hemoglobin (Hb) was prepared from molecularly imprinted polymer nanoparticles (MINPs) via electrophoretic deposition. A photo-sensitive copolymer composed of poly-γ-glutamic grafted with the fluorophore 7-amino-4-methylcoumarin was converted into nanoparticles that were imprinted with Hb. The resultant MINPs were then placed on a glassy carbon electrode (GCE) via electrophoretic deposition. Subsequent photo-crosslinking locks the recognition sites. The template was removed by extraction with a mixture of acetic acid and methanol at a ratio of 1:9 (v:v) to obtain a voltammetric sensor for Hb. The current response of the sensor at a working voltage of −260 mV is linearly related to the concentration of Hb in the range from 5 to 100 μg mL−1, and recoveries range from 98.7 to 102.3 %. Compared to the respective non-imprinted nanoparticles, the sensor displays high recognition capability and affinity for Hb.
Co-reporter:Jingcheng Liu;Xiangfei Zheng;Hu Li;Ren Liu;Qidao Mu
Polymer Bulletin 2015 Volume 72( Issue 3) pp:523-533
Publication Date(Web):2015/03/01
DOI:10.1007/s00289-014-1289-9
A series of novel branched methacrylate copolymers (BPMBMV) were synthesized via the mercapto chain transfer polymerization using methacrylic acid, maleic anhydride, benzyl methacrylate, and 4-vinyl benzyl thiol. Then, BPMBMV reacted with hydroxyethyl acrylate to obtain branched UV-curable copolymer H-BPMBMV, which were characterized by fourier transfer infrared spectra and proton nuclear magnetic resonance spectra. The molecular weights and glass transition temperature (Tg) of the polymers decreased with the addition of VBT. The results of photo-differential scanning calorimetry (Photo-DSC) tests showed that photo-polymerization ability of H-BPMBMV increased with the increased content of VBT. With an optimized formulation, a negative-type photoresist was prepared. The resolution of the circuit could reach as high as 20 μm, and the film of photoresist showed good acid resistance.
Co-reporter:Rong-li Zhang, Sheng Xu, Jing Luo, Dong-jian Shi, Chen Liu and Xiao-ya Liu
RSC Advances 2014 vol. 4(Issue 48) pp:25106-25113
Publication Date(Web):29 May 2014
DOI:10.1039/C4RA01094A
Nanohybrids, comprising gold nanoparticles (Au NPs) and polymer NPs have attracted significant attention in recent years due to their excellent physical and chemical properties. In this work, a novel kind of nanohybrids based on Au NPs and biocompatible poly(γ-glutamic acid)-graft-3,4-dihydroxy-L-phenylalanine (γ-PGA-g-DA) NPs was conveniently achieved through a green and facile one-pot strategy. By simply adding HAuCl4·3H2O to the aqueous solution of γ-PGA-g-DA copolymer, the decrease of the pH value induced the self-assembly of γ-PGA-g-DA into NPs, during which Au3+ was adsorbed in the in situ formed NPs and spontaneously reduced to Au NPs by the dopamine moieties of γ-PGA-g-DA, leading to the formation of Au@γ-PGA-g-DA nanohybrids. In the reaction process, γ-PGA-g-DA was used as scaffold and reductant simultaneously, avoiding the use of extra toxic reducing reagents. Interestingly, the particle size and clustering of Au NPs in Au@γ-PGA-g-DA nanohybrids were varied with the loadings of HAuCl4·3H2O. This one-pot preparation process is very simple, fast, and completely based on the principles of green chemistry. Furthermore, the resultant biocompatible Au@γ-PGA-g-DA nanohybrids were used to detect L-tryptophan and exhibited a good analytical performance. The novel Au@γ-PGA-g-DA nanohybrids are a promising system for detecting the amino acids and biological species.
Co-reporter:Yan Yuan, Ren Liu, Chunlin Wang, Jing Luo, Xiaoya Liu
Progress in Organic Coatings 2014 Volume 77(Issue 4) pp:785-789
Publication Date(Web):April 2014
DOI:10.1016/j.porgcoat.2014.01.001
•We propose a new anti-fog coating system containing sulfonic acid group.•The optimum coating formula with great anti-fog properties was given.•The UV-cured coatings exhibit good mechanical properties and optical transparency.A series of UV curable hydrophilic acrylate polymers containing sulfonic acid group was prepared via free radical copolymerization using 2-acrylamido-2-methyl propane sulfonic acid (AMPS) as hydrophilic monomer, which were used as prepolymers for anti-fog coatings. The expected structures were confirmed by FT-IR, 1H NMR and gel permeation chromatography (GPC). These UV-curable acrylate polymers were then mixed with reactive diluents and photoinitiator to form coating formulas. Various substrates were coated with these formulas and cured under UV exposure to obtain transparent coatings with good adhesion and hardness. The anti-fog properties of UV-cured coating were measured by contact angle test and anti-fog test. The results showed that the AMPS content in prepolymer had a great influence on the anti-fog properties of UV-cured coating. The formula was optimized and the corresponding UV-curing anti-fog coating was manufactured. The test results indicated that the coatings showed good mechanical properties, great optical transparency and excellent anti-fog performance.
Co-reporter:Yan Yuan, Ning Chen, Ren Liu, Shengwen Zhang, Xiaoya Liu
Materials Research Bulletin 2014 50() pp: 392-398
Publication Date(Web):
DOI:10.1016/j.materresbull.2013.11.024
Co-reporter:Shengwen Zhang, Meng Guo, Zidong Chen, Qiu Hua Liu, Xiaoya Liu
Colloids and Surfaces A: Physicochemical and Engineering Aspects 2014 Volume 443() pp:525-534
Publication Date(Web):20 February 2014
DOI:10.1016/j.colsurfa.2013.12.019
•A polyurethane was grafted onto the surface of silica particles (PU-silica) via amine–isocyanate coupling reactions.•The grafted PU chains enhanced the silica–PUA interfacial interaction and improved their compatibility.•The PU-silica enhanced the mechanical and thermal properties of the PUA films.The colloidal silica was modified with 3-aminopropyltrimethoxysilane (APTES), and then further treated with NCO-terminated poly (ethylene glycol) methacrylate based oligomer to yield a photosensitive polyurethane modified silica (PU-silica). IR and TGA results confirmed the existence of grafted PU chains at the surface of silica. In compared to silica modified with the silane coupling agents (APTES, MEMO), the grafted PU chains enhanced interfacial interaction and compatibility between silica and polyurethane acrylate (PUA) matrix, which was further proved by rheological behavior and DMA analysis. The SEM showed that small PU-silica clusters were homogeneously dispersed in PUA matrix. The PU-silica nanoparticles functioned effectively as a multifunctional cross-linker as well as a reinforcing filler and significantly enhanced the Young's modulus, tensile strength, and thermal stability of PUA nanocomposites.A photosensitive polyurethane was grafted onto the surface of silica particles using amine–isocyanate coupling reactions. The grafted PU chains enhanced the silica–PUA interfacial interaction and improved their compatibility, and this allowed a homogeneous dispersion of the small PU-silica clusters in the PUA matrix. The PU-silica nanoparticles functioned effectively as multifunctional cross-linkers as well as reinforcing fillers and significantly enhanced the Young's modulus, tensile strength, and thermal stability of PUA nanocomposites.
Co-reporter:Chenglin Yi, Jianhua Sun, Donghua Zhao, Qiong Hu, Xiaoya Liu, and Ming Jiang
Langmuir 2014 Volume 30(Issue 23) pp:6669-6677
Publication Date(Web):May 20, 2014
DOI:10.1021/la500326u
Polymeric micelles could be used as model polymeric particulate emulsifiers to elucidate the correlation between the micellar structure and their emulsifying performance. Photo-cross-linkable and pH-responsive micelles were prepared with amphiphilic random copolymers, poly(7-(4-vinylbenzyloxyl)-4-methylcoumarin-co-acrylic acid) (PVMAA), via the self-assembly in selective-solvent DMF/H2O and then used as polymeric particulate emulsifiers to stabilize toluene-in-water emulsions. Primary micelles, based on PVMAA with 12 mol % of hydrophobic composition, were chosen as model to investigate the influence of photo-cross-linking on the emulsifying performance. The larger shrinkage degree by photo-cross-linking (SDC) the micelles have, the lower emulsifying efficiency the micelles exhibit. Furthermore, the structural transitions of micelles with SDC of 0% and 95% in response to pH change were comparatively confirmed by a combination of electrophoresis, dynamic light scattering (DLS), and transmission electron microscopy (TEM). The micelles of various states, manipulated by photo-cross-linking and pH changes, were used as emulsifiers to stabilize toluene-in-water or styrene-in-water emulsions. For the un-cross-linked micelles, polymer chains gradually protrude from micelles with pH increasing, which benefits the increase in the emulsifying efficiency of micelles. However, as pH elevated over 8, the stability of emulsions significantly decreases due to the disintegration of micelles. On the contrary, micelles with SDC of 95% keep their structural integrity and become more rigid as pH increase, leading to lower emulsifying efficiency of micelles and worse stability of the emulsions. This paper provides a new insight into the principles governing the extremely high emulsifying efficiency of polymeric particulate emulsifiers and pH-dependent or pH-responsive properties of the formed emulsions.
Co-reporter:Ren Liu, Mo Sha, Sisi Jiang, Jing Luo, Xiaoya Liu
Talanta 2014 Volume 120() pp:76-83
Publication Date(Web):March 2014
DOI:10.1016/j.talanta.2013.12.002
•A green and facile approach for imprinting protein was provided.•MWNTs was employed as solid supporting materials for MIP.•MWNTs@MIPs showed good specific recognition behavior towards template proteins.This study describes a green, facile and low cost approach for imprinting protein on the surface of multi-walled carbon nanotubes (MWNTs) using papain as the template, dopamine as the functional monomer. By simply mixing MWNTs, dopamine, template protein in weak alkaline aqueous solution, a thin adherent polydopamine (PDA) film imprinted with protein was spontaneously obtained on the surface of MWNTs to produce the imprinted nanomaterials (MWNTs@MIPs). The obtained MWNTs@MIPs were characterized with Fourier transform infrared spectrometer (FT-IR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The adsorption process of the MWNTs@MIPs towards template protein was investigated in detail. The effects of the concentration of the monomer and template, polymerization time, extraction process were optimized. The prepared MWNTs@MIPs show fast binding kinetics, high binding capacity and acceptable specific recognition behavior towards template proteins. Furthermore, the stability and regeneration were also investigated, which indicated that the MWNTs@MIPs had good reusability. The good recognizing behavior coupled to the low cost and facile one-step preparation make the MWNTs@MIPs attractive for separation and specific protein recognition.Schematic illustration of the preparation of MWNTs@MIPs and adsorption isotherms of template protein on MWNTs@MIPs and MWNTs@NIPs.
Co-reporter:Jing Luo;Qun Zhou;Jun Sun;Ren Liu
Colloid and Polymer Science 2014 Volume 292( Issue 3) pp:653-660
Publication Date(Web):2014 March
DOI:10.1007/s00396-013-3108-5
Well-defined water-dispersible polyaniline (PANI) nanoparticles were synthesized by in situ chemical oxidative polymerization of aniline in the presence of an amphiphilic P(AMPS-co-VM) copolymer micelle. P(AMPS-co-VM) copolymer was prepared by the free radical polymerization of 7-(4-vinylbenzyloxyl)-4-methyl-coumarin (VM) and 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) which can self-assemble into micelles in aqueous solution. Here, P(AMPS-co-VM) copolymer micelle is used not only as soft template but also as acid dopant in our reaction system. The structure, size, and morphology of PANI nanoparticles were characterized by various experimental techniques. It is found that the morphology and the size of the PANI nanoparticles strongly depend on the molecular characteristics of the P(AMPS-co-VM) copolymer. The synthesized PANI nanoparticles behaved as particulate emulsifier for the stabilization of oil-in-water emulsions.
Co-reporter:Jingcheng Liu;Jing Luo;Ren Liu;Jinqiang Jiang
Colloid and Polymer Science 2014 Volume 292( Issue 1) pp:153-161
Publication Date(Web):2014 January
DOI:10.1007/s00396-013-3065-z
Photosensitive copolymer P(St-alt-MAn)-co-P(VM-alt-MAn) was synthesized and employed to disperse multi-wall carbon nanotubes (MWCNTs). It was found that copolymer could form micelles in aqueous solution and adsorb onto the surface of MWCNTs to produce micelle-encapsulated MWCNTs (e-MWCNTs) by in situ photo crosslinking after irradiation with ultraviolet light and a stable suspension of e-MWCNTs in aqueous solution was obtained. When deposited onto polyaniline (PANI)-modified glassy carbon electrodes, a thin film of e-MWCNTs composite was obtained and the performance of the e-MWCNTs/PANI electrode toward dopamine was then evaluated. The experimental results suggest that the hybrid film modified electrode exhibits a dramatic electrocatalytic effect on the oxidation of dopamine (DA), as evidenced by a marked enhancement of the current response. A series of CVs was obtained by modified glassy-carbon electrodes with different size of micelles was also researched. The result shows that the peak current increased with the increasing size of micelles. A linear calibration plot was obtained in a wide range of 1.0 × 10−7–1.0 × 10−3 M and the detection limit was 5.0 × 10−8 M. In addition, the interference from ascorbic acid (AA) was effectively suppressed due to the presence of the negatively charged carboxylate groups of copolymer on the outside of MWCNTs which repels AA anions and provides a transport channel only for DA cations.
Co-reporter:Jiadi Sun, Xiaoya Liu, Long Meng, Wei Wei, and Yufeng Zheng
Langmuir 2014 Volume 30(Issue 37) pp:11002-11010
Publication Date(Web):2017-2-22
DOI:10.1021/la5010177
A novel biomedical coating was prepared from self-assembled colloidal particles through direct electrodeposition. The particles, which are photo-cross-linkable and nanoscaled with a high specific surface area, were obtained via self-assembly of amphiphilic poly(γ-glutamic acid)-g-7-amino-4-methylcoumarin (γ-PGA-g-AMC). The size, morphology, and surface charge of the resulting colloidal particles and their dependence on pH, initial concentrations, and UV irradiation were successfully studied. A nanostructured coating was formed in situ on the surface of magnesium alloys by electrodeposition of colloidal particles. The composition, morphology, and phase of the coating were monitored using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, and X-ray diffraction. The corrosion test showed that the formation of the nanostructured coating on magnesium alloys effectively improved their initial anticorrosion properties. More importantly, the corrosion resistance was further enhanced by chemical photo-cross-linking. In addition, the low cytotoxicity of the coated samples was confirmed by MTT assay against NIH-3T3 normal cells. The contribution of our work lies in the creation of a novel strategy to fabricate a biomedical coating in view of the versatility of self-assembled colloidal particles and the controllability of the electrodeposition process. It is believed that our work provides new ideas and reliable data to design novel functional biomedical coatings.
Co-reporter:Jing Luo, Yuze Chen, Qiang Ma, Ren Liu and Xiaoya Liu
RSC Advances 2013 vol. 3(Issue 39) pp:17866-17873
Publication Date(Web):31 Jul 2013
DOI:10.1039/C3RA42426J
A new class of graphene/polyaniline multilayer film was constructed by layer-by-layer self-assembly, using poly(sodium 4-styrenesulfonate) stabilized graphene sheets (PSS-GS) and polyaniline (PANI) as building blocks. Poly(sodium 4-styrenesulfonate) (PSS) was used not only to stabilize the graphene sheets, but also facilitate the growth of the PSS-GS/PANI multilayer films via electrostatic interactions between PSS-GS and PANI. Furthermore, PSS can also act as a dopant for PANI during redox reactions. Ultraviolet-visible absorption spectrum (UV-vis), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy and scanning electron microscopy (SEM) results demonstrate the successful fabrication of the PSS-GS/PANI hybrid multilayer films. Electrochemical experiments show that PSS-GS inside the multilayer film can dope PANI effectively and the multilayer film still presents a redox activity at neutral pH. In addition, the obtained nanostructured PSS-GS/PANI multilayer film is very stable and shows high electrocatalytic ability toward H2O2, which makes it an ideal substrate for H2O2 detection and offers great promise for sensing.
Co-reporter:Jingcheng Liu, Ren Liu, Yan Yuan, Shengwen Zhang, Xiaoya Liu
Progress in Organic Coatings 2013 Volume 76(Issue 9) pp:1251-1257
Publication Date(Web):September 2013
DOI:10.1016/j.porgcoat.2013.03.022
•Novel superhydrophobic conductive coatings were prepared.•The coatings can be prepared by spin or roller coating and are easy to repair.•The superhydrophobicity and conductivity of the coatings are excellent.•Chain transfer monomer 4-vinyl benzyl thiol (VBT) was synthesized.Novel superhydrophobic antistatic coatings were prepared from the branched alternating copolymers P(St-alt-MAn) and carbon nanotubes through a facile method. Pristine multiwalled carbon nanotubes (MWCNTs) were non-covalently modified by an organic–inorganic hybrid of the branched copolymers P(St-alt-MAn) and silica with the existence of γ-aminopropyl-triethoxysilane. The modified MWCNTs were mixed with tetraethyl orthosilicate in ethanol, coated with a fluoroalkylsilane, and then heat treated to obtain the superhydrophobic antistatic coatings. Scanning electron microscopy (SEM) showed that the coatings have a micrometer- and nanometer-scale hierarchical structure similar to that of lotus leaves with high water contact angles (>170°). In addition, the relationship between content of MWCNTs and the properties of the coatings, as well as the effect of cure temperature on contact angle values were investigated systematically.
Co-reporter:Jingcheng Liu;Ren Liu;Jinqiang Jiang
Journal of Applied Polymer Science 2013 Volume 130( Issue 4) pp:2588-2593
Publication Date(Web):
DOI:10.1002/app.39372
ABSTRACT
This manuscript describes the use of a novel water-soluble photosensitive α-cyclodextrin modified coumarin (α-CD-C) to disperse carbon nanotubes (CNTs) in water. First, using epichlorohydrin as the bridged unit, water-soluble α-cyclodextrin (α-CD) was introduced to modify 7-hydroxy-4-methylcoumarin and prepare α-CD-C. α-CD-C was characterized with hydrogen nuclear magnetic resonance spectra (1H-NMR) and High pressure liquid chromatography-mass spectrometry. The photodimerization experiment showed that α-CD-C could photodimerize upon 365 nm irradiation, and then photo-de-crosslink upon the subsequent 254 nm irradiation. Next, α-CD-C was used to disperse CNTs in water. Transmission electron microscope and scanning electron microscope demonstrated that α-CD-C effectively adsorbed onto the surface of CNTs. The α-CD-C is an efficient dispersant for CNTs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2588–2593, 2013
Co-reporter:Jingcheng Liu;Xiaomei Xiong;Ren Liu;Jinqiang Jiang
Polymer Bulletin 2013 Volume 70( Issue 6) pp:1795-1803
Publication Date(Web):2013 June
DOI:10.1007/s00289-013-0922-3
Novel branched alternating copolymers poly(styrene-alt-maleic anhydride) (BPSMA) were synthesized through free radical polymerization with styrene, maleic anhydride, and chain transfer monomer, 4-vinyl benzyl thiol. The successful synthesis of BPSMA was confirmed by a triple detection system including gel permeation chromatography, multiangle laser light scattering, and differential viscosity detectors, as well as thermal analysis (differential scanning calorimetry). This methodology proposes good prospects for scaling-up and thereby offers a wide range of branched alternating copolymers at low cost.
Co-reporter:Jing Luo, Sisi Jiang, and Xiaoya Liu
The Journal of Physical Chemistry C 2013 Volume 117(Issue 36) pp:18448-18456
Publication Date(Web):August 16, 2013
DOI:10.1021/jp405171w
Molecular imprinting at nanomaterial surfaces has shown good prospects to extract templates easily and to achieve excellent performances such as large binding capacity and fast adsorption. In this work, we describe a one-step approach to synthesize a novel surface protein-imprinted nanomaterial employing graphene as the supporting substrate and dopamine as the polymerizing monomer. By simply immersing graphene oxide (GO) in a weak alkaline solution of dopamine (DA) containing bovine hemoglobin (BHb), GO nanosheet was readily converted to reduced GO (RGO) by dopamine with simultaneous capping by a thin polydopamine film imprinted with BHb leading to the BHb imprinted PDA@RGO nanomaterials. Fourier transform infrared (FT-IR), ultraviolet–visible (UV–vis), Raman spectra, X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and nitrogen adsorption experiments have been used to characterize the resulting imprinted PDA@RGO. The whole reaction process was conducted in aqueous solution at ambient temperature, which is easy to scale up at a low cost without pollution. In addition, because of the unique properties of graphene (large surface area, high surface-to-volume ratio) and polydopamine (high biocompatibility and controllable thickness), the prepared imprinted PDA@RGO not only possessed high binding capacity (198 mg/g) but also exhibited a fast adsorption kinetics (adsorb 89% of the maximum amount within 5 min) and good selectivity toward template protein (the imprinting factor α is 4.95). The outstanding recognizing behavior coupled to the low production cost and facile, quick, green preparation procedure makes the imprinted PDA@RGO attractive in specific protein recognition and separation, biosensors, and biochips.
Co-reporter:Ren Liu;Fenlei An;Shengwen Zhang;Jing Luo
Polymer Science, Series A 2013 Volume 55( Issue 4) pp:225-232
Publication Date(Web):2013 April
DOI:10.1134/S0965545X13040093
A photosensitive random copolymer UPDHES was prepared by introducing the acrylate groups into the side chain of the copolymer composed of N,N-dimethylaminomethyl methacrylate (DMAEMA), 2-hydroxyethyl acrylate (HEA), 2-ethylhexyl acrylate (EHA), and styrene (St) (PDHES). The molecular structure of UPDHES was characterized by FTIR and 1H NMR analyses. Self-assembling of the random copolymer UPDHES in water formed positively charged photosensitive particles, and the particles were measured by TEM to be spherical-like nano-particles range from 20–90 nm. The oriented deposition of the particles on gold electrode was investigated with the cyclic voltammetry and TEM under low applied voltage. The influence of high applied voltage on current density in electrodeposition process and thickness of films were investigated also. Besides, the photopolymerization rate and final C=C conversion reached to the highest values with 3 wt % Irgacure 1173 addition, whereas decreased as further added. Moreover, an exposure-development procedure of electrodeposition UPDHES film produced developed diagram with resolution of 15 μm.
Co-reporter:Youhua Tao, Ren Liu, Mingqing Chen, Cheng Yang and Xiaoya Liu
Journal of Materials Chemistry A 2012 vol. 22(Issue 2) pp:373-380
Publication Date(Web):03 Nov 2011
DOI:10.1039/C1JM13950A
The poor stability of micellar drug delivery system in vivo due to large volume dilution often leads to premature drug release with low therapeutic efficacy. In this study, shell cross-linked micelles of graftlike block copolymer bearing biodegradable ε-caprolactone branches (PMAA-b-PFM) were prepared to be used as a novel carrier for paclitaxel (PTX). PTX was successfully encapsulated into the hydrophobic cores of the cross-linked micelles using the dialysis method. The resultant PTX-loaded cross-linked micelles were about 99 nm in diameter with spherical shape and high encapsulation efficiency. The PTX-loaded cross-linked micelles had smaller sizes and better stability as compared to the non-cross-linked controls. Fluorescence microscopy and flow cytometry studies showed that PTX-loaded cross-linked micelles had excellent cellular uptake ability by bone marrow derived macrophages and human glioma U87 cells. Cellular uptake of cross-linked micelles was found to be higher than non-cross-linked controls due to smaller size. In vitro cytotoxicity studies also revealed that the PTX-loaded cross-linked micelles exhibit high anti-cancer activity to U87 cells. These results suggested that cross-linked PMAA-b-PFM micelles could be a potential vehicle for delivering hydrophobic chemotherapeutic drugs to tumors.
Co-reporter:Jing Luo, Sisi Jiang, Hongyan Zhang, Jinqiang Jiang, Xiaoya Liu
Analytica Chimica Acta 2012 Volume 709() pp:47-53
Publication Date(Web):4 January 2012
DOI:10.1016/j.aca.2011.10.025
A novel, stable and sensitive non-enzymatic glucose sensor was developed by potentiostatically electrodepositing metallic Cu nanoparticles on graphene sheets. The electrochemical performance of the Cu-graphene sheets electrode for detection of glucose was investigated by cyclic voltammetry and chronamperometry. The Cu-graphene sheets electrode displayed a synergistic effect of copper nanoparticles and graphene sheets towards the oxidation of glucose in alkaline solution, showing higher oxidation current and negative shift in peak potential. At detection potential of 500 mV, the Cu-graphene electrode sensor presented a wide linear range up to 4.5 mM glucose with a detection limit of 0.5 μM (signal/noise = 3). In addition, the sensor responds very quickly (<2 s) with addition of glucose. Furthermore, the Cu-graphene sheets electrode exhibits high stability and selectivity to glucose, and the poisoning by chloride ion as well as interference from the oxidation of common interfering species (ascorbic, dopamine, uric acid and carbohydrate) are effectively avoided. The Cu-graphene sheets electrode allows highly selective and sensitive, stable and fast amperometric sensing of glucose, which is promising for the development of non-enzymatic glucose sensor.Graphical abstractHighlights► We electrodeposited Cu nanoparticles on graphene sheets. ► The obtained Cu-graphene sheets nanocomposite is a good catalyst for the oxidation of glucose. ► Wide linear range, low detection limit as well as quick response for glucose. ► Easy fabrication, low cost, good reproducibility and perfect specificity to glucose in the presence of interferents.
Co-reporter:Youhua Tao, Jing Xu, Mingqing Chen, Huiyu Bai, Xiaoya Liu
Carbohydrate Polymers 2012 Volume 88(Issue 1) pp:118-124
Publication Date(Web):17 March 2012
DOI:10.1016/j.carbpol.2011.11.075
In this study, cross-linked hyaluronan-styrylpyridinium (HA-SbQ) micelles were prepared to be used as a novel carrier for paclitaxel (PTX). PTX was successfully encapsulated into the hydrophobic cores of the cross-linked micelles using the dialysis method. The resultant PTX-loaded cross-linked HA-SbQ micelles were about 113 nm in diameter with spherical shape and high encapsulation efficiency. Fluorescence microscopy and high-performance liquid chromatography studies showed that PTX-loaded cross-linked HA-SbQ micelles had excellent cellular uptake ability by bone marrow derived macrophages (BMM) and human glioma U87 cells. Cellular uptake of cross-linked HA-SbQ micelles was found to be higher than that of un-cross-linked ones due to smaller size and more stable structure. In vitro cytotoxicity studies also revealed that the PTX-loaded cross-linked micelles were more potent than those of PTX-loaded un-cross-linked micelles and free PTX. These results suggested that cross-linked HA-SbQ micelles could be a potential vehicle for delivering hydrophobic chemotherapeutic drugs to tumors.Highlights► Cross-linked hyaluronan-styrylpyridinium micelles were prepared. ► Paclitaxel was successfully encapsulated into the cross-linked micelles. ► Paclitaxel-loaded cross-linked micelles had excellent cellular uptake ability. ► Paclitaxel-loaded cross-linked micelles significantly reduced tumor cell viability.
Co-reporter:Yunyan Xu, Jingcheng Liu, Changsen Du, Shaohai Fu, Xiaoya Liu
Progress in Organic Coatings 2012 Volume 75(Issue 4) pp:537-542
Publication Date(Web):December 2012
DOI:10.1016/j.porgcoat.2012.05.014
Hyper-branched poly(styrene-alt-maleic anhydride) (BPSMA) was used as a dispersant to disperse carbon black (CB) in aqueous media. The dispersing ability of BPSMA for CB was estimated by measuring the particle size, zeta potential, stability to temperature and centrifugal stability of BPSMA-dispersed CB dispersions. The experimental results showed that BPSMA prepared with a molar ratio of 4-vinylphenyl methanethiol (VPMT), St and MA at 6:47:47 and a mass ratio of BPO and (VPMT + St + MA) at 1:50 exhibited optimal dispersing ability when the CB dispersion was at pH 8, and a mass ratio of BPSMA and CB was about 1:5. Compared to linear poly(styrene-alt-maleic anhydride) (LPSMA), BPSMA prepared CB pigment dispersion with a smaller particle size, a more narrow particle size distribution and higher stabilities.Graphical abstractHighlights► Nanoscale CB dispersion is prepared using a novel dispersant. ► The synthesized BPSMA which is more suitable for CB dispersing is determined. ► The CB dispersion prepared with BPSMA shows small particle size and high stability.
Co-reporter:Youhua Tao;Ling Ai;Huiyu Bai
Journal of Polymer Science Part A: Polymer Chemistry 2012 Volume 50( Issue 17) pp:3507-3516
Publication Date(Web):
DOI:10.1002/pola.26159
Abstract
Photocrosslinked hyaluronic acid/poly(vinyl alcohol)-styrylpyridinium (HA/PVA-SbQ) hydrogels were synthesized for controlled antitumor drug delivery. The photocrosslinking reaction was rapid, and the time required for completely converting into the insoluble hydrogels was less than 500 s on exposure to 5 mW/cm2 UV light irradiation. The resulting hydrogels exhibited sensitivity to the pH value of the surrounding environment. Scanning electron microscopic analysis revealed that the morphology and the pore size of the hydrogels could be controlled by changing the ratio of HA and PVA-SbQ in the formulations. Paclitaxel (PTX)-loaded hydrogel could also be formed rapidly by UV irradiation of a mixed solution of HA/PVA-SbQ and PTX. Release profiles of PTX from the hydrogels showed pH-dependent and sustained manner. Moreover, our data revealed that PTX released from the HA hydrogels remained biologically active and had the capability to kill cancer cells. In contrast, control groups of HA hydrogels without PTX did not exhibit any cytotoxicity. This study demonstrates the feasibility of using HA-based hydrogels as a potential carrier for chemotherapeutic drugs for cancer treatments. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Co-reporter:Jingcheng Liu 刘敬成;Xiuli Jia;Shengwen Zhang
Journal of Wuhan University of Technology-Mater. Sci. Ed. 2012 Volume 27( Issue 4) pp:694-701
Publication Date(Web):2012 August
DOI:10.1007/s11595-012-0531-2
Liquid carboxyl-terminated poly(butadiene-co-acrylonitrile)(CTBN)-epoxy resin(EP) prepolymers were prepared with different contents of CTBN. The chemical reactions between EP and CTBN were characterized by Fourier ransform infrared (FTIR) spectroscopy and gel permeation chromatography (GPC). The scanning electron micrograph (SEM) and dynamic mechanical analysis (DMA) of curing films showed phase separation, and the rubber particles were finely dispersed in the epoxy matrix. Mechanical properties analysis of curing films showed that impact strength and elongation at break increased significantly upon the addition of CTBN, indicating good toughness of the modified epoxy resins. Thermogravimetric analysis (TGA) showed that the incorporation of CTBN had little effect on the thermal stability of EP. Fusion-bondedepoxy (FBE) powder coatings modified with CTBN-EP prepolymers were prepared. The experimental results demonstrate the ability of CTBN-EP prepolymers, toughening technology to dramatically enhance the flexibility and impact resistance of FBE coatings without compromising other key properties such as corrosion protection.
Co-reporter:Ren Liu 刘仁;Shilin Liu;Hua Zhou;Cheng Yang
Journal of Wuhan University of Technology-Mater. Sci. Ed. 2012 Volume 27( Issue 5) pp:852-856
Publication Date(Web):2012 October
DOI:10.1007/s11595-012-0561-9
A completely green pathway for the preparation of Ag nanoparticles was proposed, by using soy protein isolate (SPI) as stabilizer under UV irradiation and H2O as the environmentally benign solvent throughout the preparation. Transmission electronic microscopy (TEM) and zeta potential characterization results indicated that the Ag nanoparticles were stable and well dispersed with an average diameter about 13 nm, and X-ray diffraction (XRD) analysis of SPI/Ag composite nanoparticles confirmed the formation of metallic silver. UV-Vis spectrum showed that the Ag nanoparticles dispersion solution had the maximum absorbance at about 430 nm due to surface plasmon resonance of the Ag nanoparticles. Infrared spectroscopy confirmed that the polypeptide backbone of SPI was not cleaved during the conjugation process and that some active amino groups were oxidized. The SPI/Ag composite nanoparticles have excellent antibacterial activity against two representative bacteria, staphylococcus aureus (Gram positive) and escherichia coli (Gram negative) in the presence of SPI.
Co-reporter:Youhua Tao, Yiqun Yang, Dongjian Shi, Mingqing Chen, Cheng Yang, Xiaoya Liu
Polymer 2012 Volume 53(Issue 7) pp:1551-1557
Publication Date(Web):22 March 2012
DOI:10.1016/j.polymer.2012.02.001
Micelles of a new amphiphilic copolymer bearing pendant thymine groups, polystyrene-co-poly (N-acryloylthymine) (PS-co-PAT), were prepared in aqueous solutions. Transmission electron microscopy and laser light-scattering studies showed that the resultant spherical micelles were nanoscale with narrow size distribution. Moreover, ratio of hydrophilic and hydrophobic contents strongly influenced the hydrodynamic radius of the spherical micelles (113–227 nm). Upon exposure of the PS-co-PAT micelles to melamine, triple hydrogen bonding recognition between melamine and thymine resulted in the aggregation of polymer micelles, and the blue phase transparent solution of the polymer micelles was accordingly changed to turbid emulsion. The aggregation of micelles and hydrogen-bonding interaction between melamine and the PS-co-PAT shell was further confirmed by 1H NMR spectra and zeta-potential measurements. These results suggested that PS-co-PAT micelles could be a potential new vehicle for melamine recognition.
Co-reporter:Jing Xu, Huiyu Bai, Chenglin Yi, Jing Luo, Cheng Yang, Wenshui Xia, Xiaoya Liu
Carbohydrate Polymers 2011 Volume 86(Issue 2) pp:678-683
Publication Date(Web):15 August 2011
DOI:10.1016/j.carbpol.2011.05.006
This article reports on the self-assembly behavior of a negatively charged hyaluronan (HA) and an oppositely charged styrylpyridinium species (specifically SbQ) in aqueous solution. Turbidity and Zeta potential measurements were utilized to explore the formation of complex micelles. These nano-sized micellar aggregates have a core–shell structure composed of a hydrophobic inner core containing aggregated SbQ molecules and a hydrophilic HA shell layer. UV spectra and DLS experiments confirmed that the micelles are photo-crosslinkable. A dimerization reaction of the SbQ molecules induced by UV light irradiation led to the crosslinking of the inner core, resulting in a decrease in the size of the micelles.Highlights► Self-assembly behavior of HA and SbQ via electrostatic interaction. ► Formation of core–shell HA/SbQ complex micelles during the self-assembly. ► UV leads to the cross-linking of micelles.
Co-reporter:ShengWen Zhang, RenLiu, JinQiang Jiang, Cheng Yang, Mingqing Chen, XiaoYa Liu
Progress in Organic Coatings 2011 Volume 70(Issue 1) pp:1-8
Publication Date(Web):January 2011
DOI:10.1016/j.porgcoat.2010.09.005
Waterborne UV-curable polyurethane (WUPU)/silica nanocomposites were prepared by in situ method using aqueous silica sol. SEM examinations of hybrid films indicated that the nanosilica were well dispersed in the matrix. Atomic force microscopy revealed that the microphase separation between polyurethane and silica was significantly affected by the amount of silica incorporated. DMA analysis showed that the nanocomposite films with silica nanoparticles showed a single tan δ peak, which implies that soft and hard segments of polyurethane are well phase mixed. The nanostructure films displayed enhanced storage modulus, tensile strength without sacrificing high elongation at break. The resulting transparent hybrid films are promising for a number of applications, e.g. for high performance water-based UV-curable coatings.Waterborne UV-curable polyurethane (WUPU)/silica nanocomposites were prepared by in situ method using aqueous silica sol. the nanosilica particles were well dispersed in the matrix. Some large silica aggregates in the magnitude of micrometer can be seen with increasing the silica content.
Co-reporter:Ren Liu 刘仁;Xiaojie Li;Fenglei An
Journal of Wuhan University of Technology-Mater. Sci. Ed. 2011 Volume 26( Issue 6) pp:1098-1102
Publication Date(Web):2011 December
DOI:10.1007/s11595-011-0370-6
A series of photosensitive random copolymers (UPDHES) were prepared by introducing acrylate groups onto the side chain of the copolymer backbone of N, N-domethyl amimethyl methacrylate (DMAEMA), 2-hydroxypropyl acrylate (HEA), 2-ethylhexyl acrylate (EHA), and styrene (St) (PDHES). The molecular structure of UPDHES was characterized by FTIR, 1HNMR and GPC. The photopolymerization kinetics of UPDHES with different C=C content was investigated using real time FTIR in which it was found that the UPDHES system had notable photosensitivity. The effect of C=C content on the properties of cured films were studied by evaluating various film properties such as thermal stability, glass transition temperature and tensile properties. The thermal degradation of cured films was investigated via thermogravimetric analysis/infrared spectrometry (TGA-IR). Thus a series of UV-curable electrodeposition coatings with good photosensitivity and mechanical properties were prepared from a low-cost photosensitive random copolymer.
Co-reporter:Xiaoya Liu, Chenglin Yi, Ye Zhu, Yiqun Yang, Jinqiang Jiang, Zhenggang Cui, Ming Jiang
Journal of Colloid and Interface Science 2010 Volume 351(Issue 2) pp:315-322
Publication Date(Web):15 November 2010
DOI:10.1016/j.jcis.2010.04.056
A new type of copolymer containing two alternating segments, poly-(styrene-alt-maleic anhydride)-co-poly (7-(4-vinylbenzyloxyl)-4-methylcoumarin-alt-maleic anhydride) P(St-alt-MAn)-co-P(VM-alt-MAn)(PSMVM), was prepared. The copolymer self-assembled into nanoparticles with internal microphase structures in water because the hydrophilicity of segment P(VM-alt-MAn) is higher than that of P(St-alt-MAn). The particle size, morphology, ζ potential and surface properties and their dependence on the pH and slat concentrations were studied with a combination of techniques. The nanoparticles of PSMVM showed surface activity and pH sensitivity for producing Pickering oil-in-water emulsions. The emulsion volume increased and the size of oil/water droplet decreased with increasing salt concentration. Furthermore, cross-linked nanoparticles (CLPs) were obtained by photo-dimerization of the pendent coumarin groups in PSMVM under UV irradiation. The emulsions produced by using the CLPs as emulsifiers showed even better stability upon standing. Solid oil-phase droplets were obtained by preparation of CLPs-stabilized Pickering emulsions with an oil phase of styrene containing the initiator AIBN followed by the polymerization of styrene. Thus, the enrichment and aggregation of the CLPs on the emulsion droplets was visible because the solid droplets remained unchanged during the SEM sample preparation.An illustration of the synthetic route of photosensitive copolymer PSMVM (I) and the reversibly UV-cross-linking of coumarin groups (II) and the processes of self-assembly, photo-cross-linking, emulsification and solidifying of the emulsion droplet.
Co-reporter:Jinqiang Jiang, Qiaozhen Shu, Xin Chen, Yiqun Yang, Chenglin Yi, Xiaoqing Song, Xiaoya Liu and Mingqing Chen
Langmuir 2010 Volume 26(Issue 17) pp:14247-14254
Publication Date(Web):August 12, 2010
DOI:10.1021/la102771h
A novel photosensitive C-PNIPAAm comprising hydrophilic PNIPAAm conjugated with a relatively short but very hydrophobic coumarin part was designed and prepared using a coumarin-containing disulfide derivative (C-S-S-C) as transfer agent in the presence of Bu3P and water. It was found that C-PNIPAAm can form polymer micelles in aqueous solution. And the micellar morphology in aqueous solution can be photoswitched into hollow spheres according to the photodimerization of coumarin end groups upon 365 nm irradiation and reform the micellar morphology after the subsequent photoscission of dimers upon 254 nm. This instant morphology changing phenomenon was successfully monitored by dynamic light scattering (DLS) and transmission electron microscopy (TEM) measurements. TEM observations showed the small spherical shape of micelles with diameter at 30−50 nm before photo-cross-linking, the big vesicles with diameter at 200−350 nm after photo-cross-linking, and the small micelles with diameter at 30−50 nm after the subsequent photo-de-cross-linking in the first irradiation cycle. The reason for this significant morphology switching can be attributed to the reversible photoinduced amphiphilic structure transformation between the telechelic “hydrophobic end−hydrophilic chain” structure and the ABA type of “hydrophilic chain−hydrophobic center−hydrophilic chain” one upon alternating irradiation.
Co-reporter:Youhua Tao, Xiaoya Liu, Dongjian Shi, Mingqing Chen, Cheng Yang and Zhongbin Ni
The Journal of Physical Chemistry C 2009 Volume 113(Issue 15) pp:6009-6013
Publication Date(Web):2017-2-22
DOI:10.1021/jp8107073
A graftlike block copolymer strategy was used to construct hollow nanocages with changeable cavity dimensions, where a graftlike block copolymer bearing biodegradable poly(ε-caprolactone) branches (PMAA-b-PFM) was prepared by the selective hydrolysis of block copolymer of tert-butyl methacrylate and macromonomer FM [CH2═C(CH3)OOCH2CH2(OCOCH2CH2CH2CH2CH2)5OH] (PtBMA-b-PFM) precursor, which was synthesized by sequential controlled/living radical polymerizations of tBMA and FM. Self-assembling of PMAA-b-PFM into polymer micelles in water and cross-linking of the hydrophilic shell via condensation reactions between the carboxylic acid groups and the amino groups, followed by lipase degradation of the poly(ε-caprolactone) core, ultimately produces hollow nanocages. Transmission electron microscopy and laser light-scattering studies showed that the resultant hollow nanocages were nanoscale with narrow size distribution. Moreover, relative lengths of the hydrophobic and hydrophilic segments strongly influenced the hydrodynamic radius of the spherical micelles (52−101 nm) as well as the cavity size of the resultant hollow nanocages (62−85 nm in radius). The obtained polymeric nanocages should be useful in various fields, such as catalysis, drug delivery and structural material.
Co-reporter:Youhua Tao;Ren Liu;Mingqing Chen;Cheng Yang
Nanoscale Research Letters 2009 Volume 4( Issue 4) pp:
Publication Date(Web):2009 April
DOI:10.1007/s11671-009-9249-2
pH-sensitive micelles with hydrophilic core and hydrophilic corona were fabricated by self-assembling of triblock copolymer of poly(methylacrylic acid)-poly(ethylene glycol)-poly(methylacrylic acid) at lower solution pH. Transmission electron microscopy and laser light scattering studies showed micelles were in nano-scale with narrow size distribution. Solution pH value and the micelles concentration strongly influenced the hydrodynamic radius of the spherical micelles (48–310 nm). A possible mechanism for the formation of micelles was proposed. The obtained polymeric micelle should be useful for biomedical materials such as carrier of hydrophilic drug.
Co-reporter:Zae Northrup
Science 1918 Vol 47(1226) pp:638-639
Publication Date(Web):28 Jun 1918
DOI:10.1126/science.47.1226.638
Co-reporter:Jingcheng Liu, Ren Liu, Yan Yuan, Shengwen Zhang, Xiaoya Liu
Progress in Organic Coatings (September 2013) Volume 76(Issue 9) pp:1251-1257
Publication Date(Web):1 September 2013
DOI:10.1016/j.porgcoat.2013.03.022
•Novel superhydrophobic conductive coatings were prepared.•The coatings can be prepared by spin or roller coating and are easy to repair.•The superhydrophobicity and conductivity of the coatings are excellent.•Chain transfer monomer 4-vinyl benzyl thiol (VBT) was synthesized.Novel superhydrophobic antistatic coatings were prepared from the branched alternating copolymers P(St-alt-MAn) and carbon nanotubes through a facile method. Pristine multiwalled carbon nanotubes (MWCNTs) were non-covalently modified by an organic–inorganic hybrid of the branched copolymers P(St-alt-MAn) and silica with the existence of γ-aminopropyl-triethoxysilane. The modified MWCNTs were mixed with tetraethyl orthosilicate in ethanol, coated with a fluoroalkylsilane, and then heat treated to obtain the superhydrophobic antistatic coatings. Scanning electron microscopy (SEM) showed that the coatings have a micrometer- and nanometer-scale hierarchical structure similar to that of lotus leaves with high water contact angles (>170°). In addition, the relationship between content of MWCNTs and the properties of the coatings, as well as the effect of cure temperature on contact angle values were investigated systematically.
Co-reporter:ShengWen Zhang, RenLiu, JinQiang Jiang, Cheng Yang, Mingqing Chen, XiaoYa Liu
Progress in Organic Coatings (January 2011) Volume 70(Issue 1) pp:1-8
Publication Date(Web):1 January 2011
DOI:10.1016/j.porgcoat.2010.09.005
Waterborne UV-curable polyurethane (WUPU)/silica nanocomposites were prepared by in situ method using aqueous silica sol. SEM examinations of hybrid films indicated that the nanosilica were well dispersed in the matrix. Atomic force microscopy revealed that the microphase separation between polyurethane and silica was significantly affected by the amount of silica incorporated. DMA analysis showed that the nanocomposite films with silica nanoparticles showed a single tan δ peak, which implies that soft and hard segments of polyurethane are well phase mixed. The nanostructure films displayed enhanced storage modulus, tensile strength without sacrificing high elongation at break. The resulting transparent hybrid films are promising for a number of applications, e.g. for high performance water-based UV-curable coatings.Waterborne UV-curable polyurethane (WUPU)/silica nanocomposites were prepared by in situ method using aqueous silica sol. the nanosilica particles were well dispersed in the matrix. Some large silica aggregates in the magnitude of micrometer can be seen with increasing the silica content.Download full-size image
Co-reporter:Ren Liu, Jing Luo, Sharonie Ariyasivam, Xiaoya Liu, Zhigang Chen
Progress in Organic Coatings (April 2017) Volume 105() pp:143-148
Publication Date(Web):April 2017
DOI:10.1016/j.porgcoat.2016.11.009
Co-reporter:Sheng Xu, Rongli Zhang, Wei Zhao, Ye Zhu, Wei Wei, Xiaoya Liu, Jing Luo
Biosensors and Bioelectronics (15 June 2017) Volume 92() pp:
Publication Date(Web):15 June 2017
DOI:10.1016/j.bios.2016.10.058
•Polymeric self-assembled nanoparticles film serves as an immunosensor platform for the first time.•The bio-polymeric nanoparticles are prepared by simply self-assembly of two polyelectrolytes under mild conditions.•A dense nanostructured nanoparticles film is obtained via electrophoretic deposition of polymeric nanoparticles.•Large amounts of Au nanoparticles are tightly anchored and well- distributed on the surface polymeric nanoparticles film.•The prepared immunosensor shows much lower LOD and wider detection range towards carcino-embryonic antigen than other reported counterparts.In this work, a novel impedimetric immunosensor was developed based on electrophoretic deposition of polymeric self-assembled nanoparticles for the sensitive determination of carcino-embryonic antigen (CEA). Biocompatible polymeric nanoparticles γ-PGA-DA@CS were prepared by self-assembly of chitosan (CS) and dopamine modified poly(γ-glutamic acid) (γ-PGA-DA) under mild conditions. A dense and nanostructured nanoparticles film was obtained on the electrode surface by electrophoretic deposition of γ-PGA-DA@CS nanoparticles. Gold nanoparticles (Au NPs) were then tightly anchored on γ-PGA-DA@CS film with homogeneous dispersion due to numerous exposed dopamine adhesive dots present on the surface of γ-PGA-DA@CS. The obtained Au/γ-PGA-DA@CS nanocomposite film not only increases the electrode surface area in nanoscale dimension, but also provides a highly stable and biocompatible matrix for the convenient conjugation of antibody, thus providing a high-efficiency immunoassay platform. Monoclonal antibodies to carcinoembryonic antigen (CEA-Ab) were effectively immobilized on the Au/γ-PGA-DA@CS film and a label-free impedimetric immunosensor was fabricated successfully as the ultimate goal. Under optimal conditions, the resultant immunosensor exhibited a wide linear range from 2.0×10–14 g mL−1 to 2.0×10−8 g mL−1 for the detection of CEA with a low detection limit of 10 fg mL−1. To the best of our knowledge, this was the lowest detection limit compared with other counterparts of label-free impedimetric immunosensors. Moreover, the immunosensor showed high specificity, good stability and satisfactory reproducibility. As a proof of concept, the proposed strategy provided a promising and versatile platform for clinical immunoassay of other tumor markers and biomolecules.
Co-reporter:Wei Wei, Rongjie Lu, Haojie Xie, Yifan Zhang, Xue Bai, Li Gu, Rui Da and Xiaoya Liu
Journal of Materials Chemistry A 2015 - vol. 3(Issue 8) pp:NaN4322-4322
Publication Date(Web):2015/01/02
DOI:10.1039/C4TA06444E
Nitrogen-enriched and organic–inorganic hybrid polymer submicro-spheres based on highly cross-linked poly(cyclotriphosphazene-co-4,4′-sulfonyldiphenol) (PZS) were prepared using one-step precipitation copolymerization route. The chemical structure and morphology of the submicro-spheres were characterized. The adsorption behaviors of the submicro-spheres towards different organic dyes in an aqueous solution were investigated systematically. The results showed that PZS submicro-spheres could effectively adsorb methylene blue (MB), Bismarck brown Y (BY), neutral red (NR), rhodamine B (RhB), and calcein (Cal) with high adsorption capacities, but they could hardly adsorb orange G (OG), Ponceau S (PS), and methyl orange (MO), indicating that PZS submicro-spheres could adsorb guest dyes selectively. The adsorption process was found to follow the pseudo-second-order kinetic model rather than the pseudo-first-order one. Isotherm studies revealed that the Langmuir model was more suitable for describing the adsorption behavior of the PZS submicro-spheres than the Freundlich model. A probable mechanism based on the unique host–guest interactions between the submicro-spheres and the dyes was proposed and experimentally verified to explain the selective adsorption. The nitrogen-enriched PZS submicro-spheres possess electron-donating and proton-attracting abilities and could act as bases, and thus the dyes that are classified as Lewis acids (electron acceptor) and/or Brønsted acids (proton donor) could be selectively adsorbed onto the submicro-spheres by acid–base interactions. Because of the selective adsorption behavior towards different organic dyes, PZS submicro-spheres also exhibited a strong ability for separating dye mixtures in an aqueous solution.
Co-reporter:Wei Wei, Rongjie Lu, Shuyuan Tang and Xiaoya Liu
Journal of Materials Chemistry A 2015 - vol. 3(Issue 8) pp:NaN4611-4611
Publication Date(Web):2015/01/12
DOI:10.1039/C4TA06828A
Highly cross-linked and organic–inorganic hybrid poly(cyclotriphosphazene-co-curcumin) microspheres (PCPC-MS) were facilely prepared by a one-step precipitation copolymerization method, and served as a fluorescent chemical sensor for the detection of picric acid (PA) in solution phase. The photochemically inert cyclotriphosphazene moieties intentionally introduced into the structure of the sensor could play a role not only in connecting curcumin fluorophores to construct a highly cross-linked fluorescent architecture with excellent thermal stability and photobleaching stability, but also in effectively enriching PA from bulk solution to the surface of the sensor by the acid–base interaction between the acidic phenolic hydroxyl groups of PA molecules and the electron-rich nitrogen atoms of the cyclotriphosphazene units, which might facilitate the formation of a ground-state non-fluorescent complex of the microspheres and PA as well as the excited-state energy transfer from the microspheres to PA. Therefore, PCPC-MS exhibited a fluorescence quenching response towards PA with high sensitivity, efficiency, and selectivity over a number of other analytes such as 2,4,6-trinitrotoluene, 2,4-dinitrotoluene, 1,3-dinitrobenzene, 4-nitrotoluene, nitrobenzene, 4-benzoquinone, chlorobenzene, and nitromethane in methanol. In addition, PCPC-MS could also effectively detect PA in the presence of the other analytes, indicating their remarkable ability for resisting interferences and specific recognition of PA. This study provides new insights into the design and preparation of a polymer-based fluorescence chemical sensor for PA with low toxicity, a simple preparation process, and high selectivity.
Co-reporter:Youhua Tao, Ren Liu, Mingqing Chen, Cheng Yang and Xiaoya Liu
Journal of Materials Chemistry A 2012 - vol. 22(Issue 2) pp:NaN380-380
Publication Date(Web):2011/11/03
DOI:10.1039/C1JM13950A
The poor stability of micellar drug delivery system in vivo due to large volume dilution often leads to premature drug release with low therapeutic efficacy. In this study, shell cross-linked micelles of graftlike block copolymer bearing biodegradable ε-caprolactone branches (PMAA-b-PFM) were prepared to be used as a novel carrier for paclitaxel (PTX). PTX was successfully encapsulated into the hydrophobic cores of the cross-linked micelles using the dialysis method. The resultant PTX-loaded cross-linked micelles were about 99 nm in diameter with spherical shape and high encapsulation efficiency. The PTX-loaded cross-linked micelles had smaller sizes and better stability as compared to the non-cross-linked controls. Fluorescence microscopy and flow cytometry studies showed that PTX-loaded cross-linked micelles had excellent cellular uptake ability by bone marrow derived macrophages and human glioma U87 cells. Cellular uptake of cross-linked micelles was found to be higher than non-cross-linked controls due to smaller size. In vitro cytotoxicity studies also revealed that the PTX-loaded cross-linked micelles exhibit high anti-cancer activity to U87 cells. These results suggested that cross-linked PMAA-b-PFM micelles could be a potential vehicle for delivering hydrophobic chemotherapeutic drugs to tumors.
Co-reporter:Jiadi Sun, Ye Zhu, Long Meng, Wei Wei, Yang Li, Xiaoya Liu and Yufeng Zheng
Journal of Materials Chemistry A 2015 - vol. 3(Issue 8) pp:NaN1676-1676
Publication Date(Web):2015/01/02
DOI:10.1039/C4TB01683A
We report a potential example of using surface functionalization to provide magnesium alloys (Mg–Ca) with controlled release and corrosion resistance properties. A key feature of this approach is to treat the Mg–Ca surfaces with nanoparticles via electrodeposition that can stably load and controllably release bioactive agents or drugs. These photo-cross-linkable and nano-scale particles were prepared by the self-assembly of an amphiphilic poly(γ-glutamic acid)-g-7-amino-4-methylcoumarin (γ-PGA-g-AMC) with encapsulation of a vitamin; moreover, the size and morphology of the resulting particles were studied. Fluorescence microscopy analysis indicated that Vm was effectively incorporated into the γ-PGA-g-AMC particles. Scanning electron microscopy (SEM) images showed that the colloidal particles could be uniformly electrodeposited on the Mg–Ca alloys. Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analyses confirmed the successful anchoring of the particles. After the surface electrodeposition of self-assembled colloidal particles, the in vitro degradation results show that deposition of the particles was found to reduce the degradation rate of the magnesium alloys; moreover, the vitamin was controllably released for up to 20 days. Furthermore, the Mg–Ca substrate functionalized with colloidal particles containing a vitamin significantly promoted the attachment, proliferation and spread of NIH-3T3 normal cells. The entire strategy may be used in various medical devices to create coatings for improved biomedical performance.
![Carbamic acid, N-[3-(isocyanatomethyl)-3,5,5-trimethylcyclohexyl]-, 9-anthracenylmethyl ester](/data/chemimg/3782100/1977539-28-8.png)
![Carbamic acid, N-[3-(isocyanatomethyl)-3,5,5-trimethylcyclohexyl]-, 9-anthracenylmethyl ester](/data/chemimg/3782100/1977539-28-8_b.png)
![2,4(1H,3H)-PYRIMIDINEDIONE, 1-[(4-ETHENYLPHENYL)METHYL]-5-METHYL-](http://img.cochemist.com/ccimg/623600/623563-56-4.png)
![2,4(1H,3H)-PYRIMIDINEDIONE, 1-[(4-ETHENYLPHENYL)METHYL]-5-METHYL-](http://img.cochemist.com/ccimg/623600/623563-56-4_b.png)
![Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one, 2-amino-3',6'-bis(diethylamino)-](/data/chemimg/659200/74317-53-6.png)
![Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one, 2-amino-3',6'-bis(diethylamino)-](/data/chemimg/659200/74317-53-6_b.png)
![ACETAMIDE, N-[7-(ACETYLOXY)-2-OXO-2H-1-BENZOPYRAN-3-YL]-](/data/chemimg/2489100/69019-75-6.png)
![ACETAMIDE, N-[7-(ACETYLOXY)-2-OXO-2H-1-BENZOPYRAN-3-YL]-](/data/chemimg/2489100/69019-75-6_b.png)
![[2-(HYDROXYMETHYL)-2-(PROP-2-ENOYLOXYMETHYL)BUTYL] PROP-2-ENOATE](http://img.cochemist.com/ccimg/37300/37275-47-1.png)
![[2-(HYDROXYMETHYL)-2-(PROP-2-ENOYLOXYMETHYL)BUTYL] PROP-2-ENOATE](http://img.cochemist.com/ccimg/37300/37275-47-1_b.png)
-1,4-phenylene[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]-1,4-phenylene]](http://img.cochemist.com/ccimg/32100/32036-79-6.png)
-1,4-phenylene[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]-1,4-phenylene]](http://img.cochemist.com/ccimg/32100/32036-79-6_b.png)
![2-Propenoic acid, 1,1'-[2-[[3-[(1-oxo-2-propen-1-yl)oxy]-2,2-bis[[(1-oxo-2-propen-1-yl)oxy]methyl]propoxy]methyl]-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-](/data/chemimg/459700/29570-58-9.png)
![2-Propenoic acid, 1,1'-[2-[[3-[(1-oxo-2-propen-1-yl)oxy]-2,2-bis[[(1-oxo-2-propen-1-yl)oxy]methyl]propoxy]methyl]-2-[[(1-oxo-2-propen-1-yl)oxy]methyl]-](/data/chemimg/459700/29570-58-9_b.png)
![4-{1-HYDROXY-2-[(4-PHENYL-2-BUTANYL)AMINO]PROPYL}PHENOL](http://img.cochemist.com/ccimg/25100/25085-19-2.png)
![4-{1-HYDROXY-2-[(4-PHENYL-2-BUTANYL)AMINO]PROPYL}PHENOL](http://img.cochemist.com/ccimg/25100/25085-19-2_b.png)
![2-(4-chloro-3,5-dimethylphenoxy)-N'-[(3-methylthiophen-2-yl)methylidene]acetohydrazide](http://img.cochemist.com/ccimg/7000/6987-22-0.png)
![2-(4-chloro-3,5-dimethylphenoxy)-N'-[(3-methylthiophen-2-yl)methylidene]acetohydrazide](http://img.cochemist.com/ccimg/7000/6987-22-0_b.png)
![Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one, 2-(2-aminoethyl)-3',6'-bis(diethylamino)-](/data/chemimg/106200/950846-89-6.png)
![Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one, 2-(2-aminoethyl)-3',6'-bis(diethylamino)-](/data/chemimg/106200/950846-89-6_b.png)
![Acetic acid, 2-[(9-oxo-9H-thioxanthen-2-yl)thio]-](/data/chemimg/2490600/620170-13-0.png)
![Acetic acid, 2-[(9-oxo-9H-thioxanthen-2-yl)thio]-](/data/chemimg/2490600/620170-13-0_b.png)
![Propanoic acid, 2,2'-[carbonothioylbis(thio)]bis[2-methyl-](/data/chemimg/104200/355120-40-0.png)
![Propanoic acid, 2,2'-[carbonothioylbis(thio)]bis[2-methyl-](/data/chemimg/104200/355120-40-0_b.png)
![6A-[(2-aminoethyl)amino]-6A-deoxy- beta-Cyclodextrin](http://img.cochemist.com/ccimg/61000/60984-63-6.png)
![6A-[(2-aminoethyl)amino]-6A-deoxy- beta-Cyclodextrin](http://img.cochemist.com/ccimg/61000/60984-63-6_b.png)
![2-CHLORO-N-[1-(2-FLUOROBENZOYL)PIPERIDIN-4-YL]ACETAMIDE](http://img.cochemist.com/ccimg/56100/56090-54-1.png)
![2-CHLORO-N-[1-(2-FLUOROBENZOYL)PIPERIDIN-4-YL]ACETAMIDE](http://img.cochemist.com/ccimg/56100/56090-54-1_b.png)
![2,5-Furandione, polymer with ethenylbenzene and 7-[(4-ethenylphenyl)methoxy]-4-methyl-2H-1-benzopyran-2-one](/data/chemimg/3779800/1088239-99-9.png)
![2,5-Furandione, polymer with ethenylbenzene and 7-[(4-ethenylphenyl)methoxy]-4-methyl-2H-1-benzopyran-2-one](/data/chemimg/3779800/1088239-99-9_b.png)
![9H-Carbazole, 9-[(4-ethenylphenyl)methyl]-](http://img.cochemist.com/ccimg/60200/60181-05-7.png)
![9H-Carbazole, 9-[(4-ethenylphenyl)methyl]-](http://img.cochemist.com/ccimg/60200/60181-05-7_b.png)
![Poly[imino[(1S)-1-carboxy-4-oxo-1,4-butanediyl]]](http://img.cochemist.com/ccimg/25800/25736-27-0.png)
![Poly[imino[(1S)-1-carboxy-4-oxo-1,4-butanediyl]]](http://img.cochemist.com/ccimg/25800/25736-27-0_b.png)
![2H-1-Benzopyran-2-one, 7-[(4-ethenylphenyl)methoxy]-4-methyl-](/data/chemimg/3779800/314741-96-3.png)
![2H-1-Benzopyran-2-one, 7-[(4-ethenylphenyl)methoxy]-4-methyl-](/data/chemimg/3779800/314741-96-3_b.png)