Co-reporter:Ting Bai;Junjie Du;Jianxin Chen;Xiao Duan;Qiang Zhuang;Heng Chen
Polymer Chemistry (2010-Present) 2017 vol. 8(Issue 46) pp:7160-7168
Publication Date(Web):2017/11/28
DOI:10.1039/C7PY01675A
Drug delivery systems integrated with dual or multi-functionalities of stimuli-responsiveness, targeted and controlled release, and bioimaging are favorable in improving the efficiency of chemotherapy. In this study, the amphiphilic block copolymers of poly(TMC-co-DTM)-SS-POEGMA were synthesized via a combination of atom transfer radical polymerization (ATRP) of oligo(ethylene glycol) monomethyl ether methacrylate (OEGMA) and ring opening polymerization (ROP) of two monomers (trimethylene carbonate (TMC) and N3-functional cyclic carbonate monomer (Carb-N3)) on a bifunctional initiator, followed by “click” post-functionalization with alkyne-dithiomaleimide (DTM). The obtained copolymers possessed stimuli-sensitive characteristics and bright fluorescence properties, crucial in achieving the desired therapeutic efficiency. The core-labeled micelles (CLMs) obtained from poly(TMC-co-DTM)-SS-POEGMA showed desirable fluorescence characteristics compared to the alkyne-DTM monomer. Therefore, the material was used directly in cellular uptake studies and exhibited clear green fluorescence. Moreover, the camptothecin (CPT)-loaded CLMs were shown to be stable in aqueous solution and dissociated into their hydrophobic and hydrophilic components in a thiol-rich environment to release CPT. Due to the dual functionalities of reduction-responsiveness and fluorescence, these nanoparticles based on novel poly(TMC-co-DTM)-SS-POEGMA exhibited promising characteristics to be potentially used in cancer chemotherapy.
Co-reporter:
Macromolecular Bioscience 2017 Volume 17(Issue 3) pp:
Publication Date(Web):2017/03/01
DOI:10.1002/mabi.201600258
In this contribution, amphiphilic star copolymers (H40-star-PCL-a-PEG) with an H40 hyperbranched polyester core and poly(ε-caprolactone)-a-poly(ethylene glycol) copolymer arms linked with acetal groups are synthesized using ring-opening polymerization and a copper (I)-catalyzed alkyne-azide cycloaddition click reaction. The acid-cleavable acetal groups between the hydrophilic and hydrophobic segments of the arms endow the amphiphilic star copolymers with pH responsiveness. In aqueous solution, unimolecular micelles can be formed with good stability and a unique acid degradability, as is desirable for anticancer drug carriers. For the model drug of doxorubicin, the in vitro release behavior, intracellular release, and inhibition of proliferation of HeLa cells show that the acid-cleavable unimolecular micelles with anticancer activity can be dissociated in an acidic environment and efficiently internalized by HeLa cells. Due to the acid-cleavable and biodegradable nature, unimolecular micelles from amphiphilic star copolymers are promising for applications in intracellular drug delivery for cancer chemotherapy.
Co-reporter:Qingfu Ban, Heng Chen, Yi Yan, Nan Tian, Jie Kong
European Polymer Journal 2017 Volume 96(Volume 96) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.eurpolymj.2017.09.039
•The multi-component A2 + B3-type hyperbranched polymers were prepared.•Both the increase of backbone rigidity and decrease of backbone length can enhance monomer reactivity.•Better control of monomer reactivity over intramolecular cyclization and glass transition temperature.In this work, the dialkynyl-functionalized A2 monomers with different alkyls and aromatic backbones were synthesized and employed as construction units to produce multi-component A2 + B3 type hyperbranched polymers via copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The alkyl and aromatic backbones between two alkynyl groups were designed as hexyl (C6), dodecyl (C12), phenyl (Ar) and diphenyl (Ar2) to regulate monomer reactivity for investigating its effect on intramolecular cyclization and glass transition temperature (Tg). It was found that both the increase of backbone rigidity and the decrease of backbone length can enhance monomer reactivity. In addition, the differences of monomer reactivity can greatly influence the backbone compositions of hyperbranched polymers. High monomer reactivity can lead to high content of corresponding backbones, which can further control the degree of intramolecular cyclization and Tg of hyperbranched polymers. Thus, regulating monomer reactivity is an effective way to tune hyperbranched topology, backbone composition and physical properties.Download high-res image (84KB)Download full-size image
Co-reporter:Junwei Gu, Wencai Dong, Shuang Xu, Yusheng Tang, Lin Ye, Jie Kong
Composites Science and Technology 2017 Volume 144(Volume 144) pp:
Publication Date(Web):26 May 2017
DOI:10.1016/j.compscitech.2017.03.027
In this paper, a novel interfacial compatibilizer of soluble epoxy-terminated poly (p-phenylene-2, 6-benzobisoxazole) precursor (epoxy-prePBO) was synthesized to modify bisphenol A cyanate ester (BADCy) resin via copolymerization. Compared to PBO fibers/BADCy wave-transparent composites, the obtained PBO fibers/epoxy-prePBO modified BADCy (PBO fibers/PBO-co-BADCy) wave-transparent composite with 7 wt% epoxy-prePBO showed ultra-low dielectric constant (ε, 2.68) and dielectric loss tangent (tanδ, 0.0061) values, excellent mechanical properties (flexural strength, 658.5 MPa) and interlaminar shear strength (48.4 MPa), and outstanding thermal stability (THeat-resistance index, 262.9 °C). These properties proved its potential in applications, such as in radomes and antenna system of aircrafts.
Co-reporter:Jiang Guo;Haixiang Song;Hu Liu;Chunjia Luo;Yanrong Ren;Tao Ding;Mojammel A. Khan;David P. Young;Xinyu Liu;Xin Zhang;Zhanhu Guo
Journal of Materials Chemistry C 2017 vol. 5(Issue 22) pp:5334-5344
Publication Date(Web):2017/06/08
DOI:10.1039/C7TC01502J
Epoxy nanocomposites reinforced with polypyrrole functionalized nano-magnetite (Fe3O4–PPy) showed significantly enhanced electromagnetic wave absorption performance and flame retardancy. The Fe3O4–PPy nanocomposites were prepared by the surface initiated polymerization method. The epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites possess a minimum reflection loss (RL) value of −35.7 dB, which is much lower than that of either epoxy/(7.5 wt%)PPy nanocomposites with a minimum RL value of −11.0 dB or epoxy/(30.0 wt%)Fe3O4 with a minimum RL value of −17.8 dB at the same thickness (1.7 mm). Meanwhile, the bandwidth of epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites for RL < −10 dB and RL < −20 dB is 4.0 GHz and 0.8 GHz, respectively. The increased interface area, eddy current loss and anisotropic energy are essentially important to achieve higher reflection loss and broader absorption bandwidth for epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites. Moreover, the significantly reduced flammability was observed in the epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites compared with pure epoxy. The total heat release of epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites decreased from 25.5 kJ g−1 of pure epoxy to just 12.3 kJ g−1. The tensile strength of the epoxy nanocomposites was reported as well. These new nanocomposites with an enhanced electromagnetic wave absorption property and flame retardancy possess great potential for safer electromagnetic wave absorbers in the electronic industry to satisfy stringent industrial standards.
Co-reporter:Junwei Gu;Wencai Dong;Yusheng Tang;Yongqiang Guo;Lin Tang;Sruthi Tadakamalla;Bin Wang;Zhanhu Guo
Journal of Materials Chemistry C 2017 vol. 5(Issue 28) pp:6929-6936
Publication Date(Web):2017/07/20
DOI:10.1039/C7TC00222J
In this contribution, we present a new strategy for the fabrication of modified cyanate ester resins combined with ultralow dielectric properties, improved mechanical properties and high thermal and dimensional stabilities. The fluoride-containing compound 2-((3-(trifluoromethyl)phenoxy)methyl)oxirane (TFMPMO), synthesized from m-(trifluoromethyl)phenol (TFMP) and epichlorohydrin (ECH), was used to modify bisphenol A dicyanate ester (BADCy) resins via copolymerization reaction. The BADCy resin modified with 15 wt% TFMPMO presented ultralow dielectric constant (ε, 2.75) and dielectric loss tangent values (tan δ, 6.7 × 10−3), high mechanical properties (impact strength of 15.4 kJ m−2 and flexural strength of 141.0 MPa), and superior thermal and dimensional stability (THeat-resistance index of 206 °C and coefficient of thermal expansion of 6.4 × 10−5), and it possesses great potential application in radomes and antenna systems of aircraft.
Co-reporter:Xiaofei Zhang;Lixin Chen;Jin Yun;Xiaodong Wang
Journal of Materials Chemistry A 2017 vol. 5(Issue 22) pp:10986-10997
Publication Date(Web):2017/06/06
DOI:10.1039/C7TA01156C
In this work, we present, for the first time, the synthesis and characterization of magnetic Si–C–Fe hybrid microspheres and their catalytic performance in room temperature reduction of 4-nitrophenol as a representative sustainable process for converting environmental pollutants to fine chemicals. The ferrocene-modified polydivinylbenzene (Fc-PDVB) precursor was synthesized by Pt-catalyzed hydrosilylation between the residual vinyl groups on the PDVB surface and 1,1′-bis (dimethylsilyl)ferrocene, where further pyrolysis led to the formation of Fe nanocrystal-containing Si–C–Fe hybrid microspheres. The precursor and hybrid microspheres were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), BET surface area/porosity, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), magnetic properties and MAS solid-state NMR measurements. The ultimate microspherical catalyst exhibited nano- and meso-pores, a high specific surface area (i.e., 347.9 m2 g−1) and good ferromagnetic properties. Efficient catalytic activity (TOF: 0.163 s−1), 100% selectivity (to 4-aminophenol) and excellent reusability (with easy separation) have been delivered. The achieved microspheres outperform a number of nanomaterials such as supported noble metal particles, composites, monoliths and sheets. We have confirmed by DFT calculations that the activation of 4-nitrophenol via its weak non-covalent interaction with the sp2 carbon domain of Si–C–Fe hybrid microspheres contributed to the superior performance which can be extended to a range of nitrobenzenes.
Co-reporter:Qingfu Ban;Ting Bai;Xiao Duan
Biomaterials Science (2013-Present) 2017 vol. 5(Issue 2) pp:190-210
Publication Date(Web):2017/01/31
DOI:10.1039/C6BM00600K
In the cutting-edge field of cancer therapy, noninvasive photothermal therapy (PTT) has received great attention because it is considered to overcome the drawbacks of conventional surgery, radiotherapy and chemotherapy of severe body injuries and side effects on the immune system. The construction of PTT therapeutic and theranostic nanoplatforms is the key issue in achieving tumor targeting, imaging and therapy in a synergetic manner. In this review, we focus on the recent advances in constructing PTT therapeutic and theranostic nanoplatforms by integrating nanomaterials and functional polymers. The noninvasive photothermal cancer therapy mechanism and achievement strategies of PTT therapeutic and theranostic nanoplatforms are presented as well as the innovative construction strategies and perspectives for the future. Owing to their high tumor ablation efficiency, biological availability and low- or non-toxicity, PTT therapeutic and theranostic nanoplatforms are promising and emerging in medicine and clinical applications.
Co-reporter:Junwei Gu, Xudong Meng, Yusheng Tang, Yang Li, Qiang Zhuang, Jie Kong
Composites Part A: Applied Science and Manufacturing 2017 Volume 92() pp:27-32
Publication Date(Web):January 2017
DOI:10.1016/j.compositesa.2016.11.002
Hexagonal boron nitride/polymethyl-vinyl siloxane rubber (hBN/VMQ) dielectric thermally conductive composites were fabricated via kneading followed by hot compression method. The thermally conductive coefficient (λ), thermal diffusion coefficient (α), dielectric constant (ε) and dielectric loss tangent (tan δ) values were all increased with the increasing addition of hBN fillers. When the volume fraction of hBN fillers was 40 vol%, the corresponding λ and α was 1.110 W/m K and 1.174 mm2/s, 6 and 9 times than that of pure VMQ matrix, respectively. The corresponding ε and tan δ was 3.51 and 0.0054, respectively. Furthermore, the tensile strength and THeat-resistance index (THRI) values were both maximum with 20 vol% hBN fillers, tensile strength of 3.31 MPa, 12 times than that of pure VMQ matrix (0.28 MPa), and THRI of 253.8 °C. The obtained hBN/VMQ composites present great potential for packaging in continuous integration and miniaturization of microelectronic devices.
Co-reporter:Dong Yang and Jie Kong
Polymer Chemistry 2016 vol. 7(Issue 33) pp:5226-5232
Publication Date(Web):29 Jul 2016
DOI:10.1039/C6PY01168C
A highly efficient and benign strategy to synthesize hyperbranched polymers with a degree of branching of 100% was presented via a Friedel–Crafts aromatic substitution reaction of an AB2 monomer, 5-(4-phenoxyphenoxy)isobenzofuran-1,3-dione, in the presence of trifluoromethanesulfonic acid. The molecular weight (Mw: 66.1–294.8 kDa) and the polydispersity (close to 2.0) can be tuned by controlling polymerization conditions. It makes it convenient to tailor hyperbranched polymers for potential application in functional materials.
Co-reporter:Qingfu Ban and Jie Kong
Polymer Chemistry 2016 vol. 7(Issue 29) pp:4717-4727
Publication Date(Web):24 Jun 2016
DOI:10.1039/C6PY00986G
Well-defined hyperbranched polymers with long-chain backbones between the branched points (HyperMacs) are an emerging issue in topological polymers. Owing to the difficult discrimination of branching points interfered with or overlapped by long-chain backbones in nuclear magnetic resonance signals, the fine identification and quantitative characterization of intramolecular cyclization and the calculation of the degree of branching for HyperMacs are always challenges. In this contribution, a convenient expression of the macro-cyclic index (m-CI) was presented and deduced as the ratio of NA/NB of HyperMacs to that of their completely intramolecular cyclized analogues. The physical meaning of m-CI is the similarity of HyperMacs to their completely cyclized analogues. Accordingly, a m-CI closer to 1 means a high degree of intramolecular cyclization, even complete cyclization. The experimental validation via model polymers indicates that m-CI is a facile parameter to analyze intramolecular cyclization of HyperMacs. The increase of the chain length of the backbones between branched points can enhance intramolecular cyclization of HyperMacs accompanied with the increase of the m-CI value. As an original contribution to polymer science, the presentation of m-CI overcomes the difficult problem of quantitative characterization of intramolecular cyclization in long-chain hyperbranched polymers, which is helpful for a good understanding of their relationship between topological structures and properties.
Co-reporter:Heng Chen and Jie Kong
Polymer Chemistry 2016 vol. 7(Issue 22) pp:3643-3663
Publication Date(Web):30 Mar 2016
DOI:10.1039/C6PY00409A
Hyperbranched or highly branched polymers from A2 + B3 step-growth polymerization have received considerable attention as an emerging area of research due to their environmentally benign, convenient one-pot synthesis and potential for large-scale production. In this review, recent advances in the description and control of their fine topological structures are presented. Quantitative description methods, including the degree of branching (DB), the average number of cyclic structures (ANC), the cyclic index (CI) and the terminal index (TI), make the quantitative description of finely branched and intramolecular cyclic topological features possible for hyperbranched or highly branched polymers. Subsequently, the advanced control strategies for the topological structure are summarized with a focus on avoiding gelation, tailoring the degree of branching and limiting intramolecular cyclization. In addition to synthesizing soluble polymers by avoiding gelation and tailoring the degree of branching by introducing linear components, the limitation of intramolecular cyclization is the key factor in obtaining perfect hyperbranched structures with numerous terminal groups. The advances in the quantitative description and control of fine topological structures of hyperbranched polymers will promote their development and application in various fields, including traditional polymer materials and engineering and emerging biomedicine materials, energy materials and optoelectronic materials and devices.
Co-reporter:Fangfang Chen, Weifeng Zhao, Jingjing Zhang and Jie Kong
Physical Chemistry Chemical Physics 2016 vol. 18(Issue 2) pp:718-725
Publication Date(Web):08 Sep 2015
DOI:10.1039/C5CP04218F
Surface molecular imprinting for proteins is an emerging cross-field of molecular imprinting engineering and functional materials. In this contribution, we report a novel design of magnetic two-dimensional molecularly imprinted polymers (2D-MIPs) for the high recognition and separation of proteins. Bovine serum albumin-surface-imprinted polydopamines were prepared on the surfaces of the magnetic Fe3O4–graphene oxide hybrid to form magnetic 2D-MIPs for proteins. The 2D Fe3O4–graphene oxide substrate possesses a dominant surface-to-volume ratio in comparison to 3D spherical substrates with the same volume. These materials are sensitive to a magnetic field and can be easily separated using an external magnet. The binding experimental results of bovine serum albumin on magnetic 2D-MIPs and real sample analysis demonstrated the high recognition specificity, selectivity, accessibility and convenient separation of 2D-MIPs for template protein. The design and synthesis of magnetic 2D-MIPs provide a new perspective for the surface molecularly imprinted materials with potential in the recognition and separation of proteins.
Co-reporter:Shan Zhang, Heng Chen and Jie Kong
RSC Advances 2016 vol. 6(Issue 43) pp:36568-36575
Publication Date(Web):29 Mar 2016
DOI:10.1039/C6RA02824A
In this contribution, we reported reduction-cleavable amphiphilic conetworks (APCNs) by copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) of azide terminated disulfide bonds-containing poly(ε-caprolactone) (A2 macromonomer) and alkyne-terminated 4-arm polyethylene glycol (B4 macromonomer). The ratio of hydrophobic to hydrophilic parts of the APCNs was tuned by chain length of the A2 macromonomer, which gave a convenient way to control swelling capacity in an aqueous or organic phase. The swelling ratio of APCNs is up to 1100% and 1450% in water and tetrahydrofuran, respectively, with a rapid cleavage at a 5 mg mL−1 dithiothreitol concentration. The reduction-cleavable, swelling controllable APCNs are expected to possess potential for application in drug delivery systems and regeneration medicine.
Co-reporter:Chunjia Luo, Wenyan Duan, Xiaowei Yin, and Jie Kong
The Journal of Physical Chemistry C 2016 Volume 120(Issue 33) pp:18721-18732
Publication Date(Web):August 9, 2016
DOI:10.1021/acs.jpcc.6b03995
The microwave absorption materials in the X-band with high-temperature resistance are an important and urgent topic in functional materials. In this article, we present a useful and promising strategy to prepare cobalt-containing microwave absorption ceramics with high-temperature resistance. The polymer-derived ceramics were obtained via pyrolysis of carbon-rich poly(dimethylsilylene)diacetylenes coordinated with octacarbonyldicobalt. XRD and Raman spectra revealed that introduction of cobalt led to in situ formation of cobalt silicide nanocrystals and crystallized carbons (graphitic and tubular carbons), resulting in an enhanced microwave absorption property. The microwave absorption property and bandwidth could be tuned by controlling the cobalt content and annealing temperature of ceramics. When the average real permittivity, imaginary permittivity, and loss tangent of materials increased to 8.06, 3.10, and 0.39, the reflection coefficient (RC) value of as-synthesized ceramics was lower than −10 dB almost across the whole X-band (8.46–12.4 GHz). The minimum RC value of −42.43 dB at 10.55 GHz showed over 99.99% absorption of electromagnetic waves. The high-performance cobalt-containing microwave absorption ceramics possess promising potential in the field of electromagnetic interference protection.
Co-reporter:Fangfang Chen;Heng Chen;Xiao Duan;Jiqiong Jia
Journal of Materials Science 2016 Volume 51( Issue 20) pp:9367-9383
Publication Date(Web):2016 October
DOI:10.1007/s10853-016-0183-2
In this contribution, we reported a novel strategy to synthesize porous molecularly imprinted polymers (MIPs) of anticancer drug of doxorubicin hydrochloride (DOX) using reduction-cleavable hyperbranched polymers containing disulfide bonds (ds-HP-alkyne). The porous MIPs (MIP-DOX-HP) possess enhanced specific surface area and porosity by the incorporation of cleavable hyperbranched polymers from the copper(I)–catalyzed azide–alkyne click chemistry. In comparison to MIPs synthesized without using ds-HP-alkyne, MIP-DOX-HP exhibits more regular and open porous structures, which increase the loading and controlled release abilities of DOX anticancer drug. Under optimized pH condition, the total cumulative release amount of DOX at equilibrium is as high as 2134 and 1249 µg for MIP-DOX-HP and MIP-DOX, respectively. The effective and robust strategy for synthesizing MIPs using cleavable hyperbranched polymers is helpful for extending applications of MIPs in drug delivery and target-activated release systems.
Co-reporter:Xiao Duan, Heng Chen, Li Fan, and Jie Kong
ACS Biomaterials Science & Engineering 2016 Volume 2(Issue 12) pp:
Publication Date(Web):November 9, 2016
DOI:10.1021/acsbiomaterials.6b00559
In this study, we present a novel drug self-assembled delivery system (DSDs) with pH and glutathione dual responsiveness to synergistically address the problems of traditional polymer-based carriers, i.e., their low drug loading efficiency, poor biocompatibility and nonbiodegradability. The DSD system with minimum assistant substances was developed from methotrexate (MTX) model drug copolymers and polyethylene glycol (PEG), which gives the system a higher drug loading efficiency and completely avoids the use of toxic carriers. The amphiphilic block copolymers of MTX and PEG are self-assembled into stable micelles such that MTX can be delivered to tumor tissues in vivo and controllable release can be achieved for cancer therapy via the cleavage of the reversible covalent bonds in the copolymer. The micelles overlapped with lysosomes for cellular uptake, and the in vivo distribution was higher in tumor tissues. Biological evaluation and histological analysis confirmed that the DSD micelles were more effective in killing tumor cells than free MTX. In addition, there were fewer side effects in normal tissues. As a result, tumor growth could be effectively inhibited in vivo. The DSDs concept is a perfect emerging strategy to address the problems of traditional polymer-based anticancer drug carriers in a synergetic manner and offers new potential routes of cancer therapy and clinical treatments.Keywords: cleavage reactions; disulfide bonds; drug delivery; imide bonds; tumor therapy;
Co-reporter:Nan Tian, Rongchang Ning, Jie Kong
Polymer 2016 Volume 99() pp:376-385
Publication Date(Web):2 September 2016
DOI:10.1016/j.polymer.2016.07.038
•Can the toughness of epoxy resin be improved directly by controlling the topological structure of crosslinking network is studied.•Chain transfer can be used to control the topology of epoxy network when crosslinking proceeds through chain-wise polymerization.•In anionic ring-opening polymerization, the active alkoxide anions transforms into inactive hydroxyls after chain transfer, leading to lower crosslinking density.•The enhancement of toughness shows a close relation to the bimodal distribution of crosslinking density.•The free volume fraction from positrons lifetime spectrum keeps nearly constant, even the toughness of epoxy resin is enhanced significantly.A new strategy to toughen epoxy resins through control of topological structure of cross-linking network has been presented. With a tertiary amine initiator, the curing proceeded via chain-wise polymerization. The impact strength of epoxy resin increased to above 84 kJ/m2 by only increasing the curing temperature, which is much higher than the reported value of 10–30 kJ/m2 for pure epoxy resin. Meanwhile, yielding was found during uniaxial tensile and three-point bending measurements. At the molecular scale, the cross-linking density showed a bimodal distribution and decreased with increasing curing temperature. A mechanism based on controlled topology of cross-linking network has been proposed to explain these changes. The cross-linking of epoxy resins occurs via a continuous anionic ring-opening polymerization, resulting in well interpenetrated chains. The chain transfer converts active alkoxide anions into inactive hydroxyls, limiting the linear growth and cross-linking. The resultant branching structures display lower cross-linking density, serving as native tougheners at the segment scale. Chain transfer accelerates with temperature, thus the ductility increases monotonically with curing temperature. This mechanism was confirmed by deliberately introducing branching chains through a short time of high-temperature reaction at the first stage of curing. The impact strength was enhanced by 2.5 times in comparison to the samples without the initial high-temperature curing. This unique and facile strategy shows potential in directly obtaining more ductile epoxy resins materials by controlling the topology of cross-linked networks.
Co-reporter:Pei Wang, Yusheng Tang, Zhen Yu, Junwei Gu, and Jie Kong
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 36) pp:20144
Publication Date(Web):August 31, 2015
DOI:10.1021/acsami.5b05490
In this contribution, the advanced aromatic polymers with excellent antiatomic oxygen (AO) performance were designed and synthesized using molecular precursor strategy and copolymerization of polyhedral oligomeric silsesquioxane (POSS). A soluble poly(p-phenylene benzobisoxazole) (PBO) precursor, that is, TBS–PBO (tert-butyldimethylsilyl was denoted as TBS), was designed to overcome the poor solubility of PBO in organic solvents. Then the new copolymer of TBS–PBO–POSS was synthesized by the copolymerization of TBS–PBO and POSS, which possessed good solubility and film-forming ability in common organic solvents, such as N-methylpyrrolidone, N,N-dimethylacetamide, and dimethyl sulfoxide. More importantly, the TBS–PBO–POSS films exhibited outstanding antiatomic oxygen properties because of the incorporation of POSS monomers with cagelike structure into the main chain of copolymer, which drastically reduced the AO-induced erosion owing to the formation of the passivating silica layer on the surface of polymers. When the TBS–PBO–POSS films were exposed to AO effective fluences of 1.5495 × 1020 atom cm–2 (5 h) and 4.6486 × 1020 atom cm–2 (15 h), the relative mass loss was merely 0.19% and 0.41%, respectively. This work provides a new perspective and efficient strategy for the molecular design of aromatic heterocyclic polymers possessing excellent combination properties including processing convenience and antioxidative and mechanical properties, which can be employed as potential candidates to endure the aggressive environment encountered in low earth orbits.Keywords: aromatic polymers; atomic oxygen; molecular precursor; poly(p-phenylene benzobisoxazole); polyhedral oligomeric silsesquioxnae
Co-reporter:Jie Kong, Minjun Wang, Jianhua Zou, and Linan An
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 12) pp:6733
Publication Date(Web):March 16, 2015
DOI:10.1021/am509129a
High-temperature stable siliconborocarbonitride (SiBCN) ceramics produced from single-source preceramic polymers have received increased attention in the last two decades. In this contribution, soluble and meltable polyborosilazanes with hyperbranched topology (hb-PBSZ) were synthesized via a convenient solvent-free, catalyst-free and one-pot A2 + B6 strategy, an aminolysis reaction of the A2 monomer of dichloromethylsilane and the B6 monomer of tris(dichloromethylsilylethyl)borane in the presence of hexamethyldisilazane. The amine transition reaction between the intermediates of dichlorotetramethyldisilazane and tri(trimethylsilylmethylchlorosilylethyl)borane led to the formation of dendritic units of aminedialkylborons rather than trialkylborons. The cross-linked hb-PBSZ precursors exhibited a ceramic yield higher 80%. The resultant SiBCN ceramics with a boron atomic composition of 6.0–8.5% and a representative formula of Si1B0.19C1.21N0.39O0.08 showed high-temperature stability and retained their amorphous structure up to 1600 °C. These hyperbranched polyborosilazanes with soluble and meltable characteristics provide a new perspective for the design of preceramic polymers possessing advantages for high-temperature stable polymer-derived ceramics with complex structures/shapes.Keywords: high-temperature stability; hyperbranched; polyborosilazanes; SiBCN ceramics; soluble polymeric precursors
Co-reporter:Heng Chen, Shan Zhang and Jie Kong
Polymer Chemistry 2015 vol. 6(Issue 6) pp:909-916
Publication Date(Web):07 Jan 2015
DOI:10.1039/C4PY01693A
In this contribution, we investigated the evaluation strategy for intramolecular cyclic features of polymers derived from Am + Bn (m ≥ 2 and n ≥ 2) step-growth polymerization from a topological analysis perspective. The general quantitative relationship between the structural units and the cyclic structures was presented regardless of the terminal groups of polymers. Further, two strategies for evaluating cyclic features were developed. First, the general expression of the average number of cyclic structures per macromolecule (ANC) for polymers derived from the Am + Bn route was obtained, which could be easily determined by NMR and SEC analytics. The contents of cyclic structures of polymers from step-growth polymerization of monomer pairs were measured, especially for the polymers with different terminal groups. Second, a new parameter of the cyclic index (CI) was defined as the ratio of the number of terminal units to the number of dendritic units in order to determine the extent of intramolecular cyclization in polymers derived from the representative A2 + B3 route. CI < 1 refers to the intramolecular cyclic structures existing in polymers, and a lower CI value indicates a higher degree of intramolecular cyclization. The CI value can be determined using quantitative NMR spectra of polymers, thereby allowing the easy evaluation of their cyclic features. With the validation of the model polymer of polycarbosilanes from the A2 + B3 route, the ANC and CI were verified to effectively evaluate their intramolecular cyclic features.
Co-reporter:Fangfang Chen;Jingjing Zhang;Minjun Wang
Journal of Separation Science 2015 Volume 38( Issue 15) pp:2670-2676
Publication Date(Web):
DOI:10.1002/jssc.201500407
Magnetic molecularly imprinted polymers have attracted significant interest because of their multifunctionality of selective recognition of target molecules and rapid magnetic response. In this contribution, magnetic molecularly imprinted polymers were synthesized via surface-initiated reversible addition addition-fragmentation chain transfer polymerization using diethylstilbestrol as the template for the enrichment of synthetic estrogens. The uniform imprinted surface layer and the magnetic property of the magnetic molecularly imprinted polymers favored a fast binding kinetics and rapid analysis of target molecules. The static and selective binding experiments demonstrated a desirable adsorption capacity and good selectivity of the magnetic molecularly imprinted polymers in comparison to magnetic non-molecularly imprinted polymers. Accordingly, a corresponding analytical method was developed in which magnetic molecularly imprinted polymers were employed as magnetic solid-phase extraction materials for the concentration and determination of four synthetic estrogens (diethylstilbestrol, hexestrol, dienestrol, and bisphenol A) in fish pond water. The recoveries of these synthetic estrogens in spiked fish pond water samples ranged from 61.2 to 99.1% with a relative standard deviation of lower than 6.3%. This study provides a versatile approach to prepare well-defined magnetic molecularly imprinted polymers sorbents for the analysis of synthetic estrogens in water solution.
Co-reporter:Weifeng Zhao, Yusheng Tang, Jia Xi, Jie Kong
Applied Surface Science 2015 Volume 326() pp:276-284
Publication Date(Web):30 January 2015
DOI:10.1016/j.apsusc.2014.11.069
Highlights
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We functionalized the graphene sheets with poly(ionic liquid) (r-GO-PIL).
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The r-GO-PIL exhibited a capability of 1910 mg·g−1 for methyl blue from water solution.
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The facile regeneration by centrifugal separation was available for the r-GO-PIL.
Co-reporter:Heng Chen;Jiqiong Jia;Xiao Duan;Zhen Yang
Journal of Polymer Science Part A: Polymer Chemistry 2015 Volume 53( Issue 20) pp:2374-2380
Publication Date(Web):
DOI:10.1002/pola.27694
ABSTRACT
In this contribution, we present new reduction-cleavable hyperbranched disulfide bonds-containing poly(ester triazole)s with limited intramolecular cyclization, which can be synthesized by the Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC) of A2 monomer of dipropargyl 3,3′-dithiobispropionate and B3 monomer of tris(hydroxymethyl)ethane tri(4-azidobutanoate). The hyperbranched poly(ester triazole)s possess numerous terminal groups and weight-average molecular weight up to 20,400 g mol−1 with a polydispersity index in the range 1.57–2.17. The CuAAC introduces rigid triazole units into the backbones of hyperbranched poly(ester triazole)s and reduces intramolecular cyclization, which is proved by topological analysis and 1H NMR spectroscopy. The disulfide bonds on backbones endow the reduction-cleavable feature to the hyperbranched poly(ester triazole)s at the presence of dithiothreitol. It gives a novel and convenient methodology for the synthesis of reduction-responsive functional polymer with controlled topologies, and the reduction-cleavable hyperbranched poly(ester triazole)s with limited intramolecular cyclization are expected to possess potential in the application of stimuli-responsive anticancer drug nanocarriers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 2374–2380
Co-reporter:Yong Huang, Dong Zhou, Yunchuan Xie, Jianye Yang and Jie Kong
RSC Advances 2014 vol. 4(Issue 29) pp:15171-15179
Publication Date(Web):17 Mar 2014
DOI:10.1039/C4RA00970C
In this contribution, a new pathway for the regulation of sound absorption properties of silicone rubber (SR) materials was presented using worm-like mesoporous silica (MS) with nanoscaled channels and pores. The MS enhanced the sound absorption coefficient of SR in a wide range of sound frequency from 1 to 5 kHz. By introducing the MS with an average pore diameter of 5.56 nm and a specific surface area of 1026 m2 g−1, the sound absorption coefficient of the MS/SR composite was as high as 0.83 at a sound frequency of 1.8 kHz, which is nearly triple that of the pure SR. Moreover, the mechanical and thermal properties of the SR were retained in the composite. The reflection and friction of sound waves between the pore walls and the depleted energy by viscous absorption were suggested as the main mechanism responsible for the enhanced sound absorption coefficient. It is helpful to design and fabricate rubber materials with tunable sound absorption properties.
Co-reporter:Heng Chen, Jiqiong Jia, Wanbin Zhang, Jie Kong
Polymer Testing 2014 Volume 35() pp:28-33
Publication Date(Web):May 2014
DOI:10.1016/j.polymertesting.2014.02.005
In this contribution, we focused on the analysis of the topological structure of hyperbranched polymers derived from ABn (n ≥ 2) monomers. It was proved that the content of terminal groups (CT) in hyperbranched polymers only depended on the number of B functional groups in ABn monomers (n) and molar mass of linear unit of A0B(n − 1)(MA0B(n − 1)), regardless of the degree of branching. The CT of the hyperbranched polymers can be determined according to a simple expression: CT = (n − 1)/MA0B(n − 1). This formula method was verified to be a simple and reliable approach, as compared to the traditional NMR or titration methods, to determine the content of terminal groups in hyperbranched polymers based on the analysis of model hyperbranched aliphatic polyesters.
Co-reporter:Yingxue Zhou;Xiaodong Fan;Wanbin Zhang;Dan Xue
Journal of Polymer Research 2014 Volume 21( Issue 2) pp:
Publication Date(Web):2014 February
DOI:10.1007/s10965-014-0359-x
A novel kind of host-guest hydrogel possessing gel–sol phase transformation in response to temperature, oxidizing agent and glucose was prepared by ferrocene (Fc)-containing pluronic F127 and β-cyclodextrin (β-CD) linear polymer, which was synthesized in aqueous alkali by using native β-CD and epichlorohydrin in the presence of toluene. Because of the reversible association–dissociation of Fc-β-CD inclusions and F127 micelles, the gel-sol transition was easily observed. Two-dimension nuclear overhauser effect spectroscopy (2D NOESY), nuclear magnetic resonance (NMR), TEM (transmission electron microscopy) and TGA (thermogravimetric analysis) measurements were used to clarify the inclusion complexes of Fc-β-CD. The results showed that the formation of inclusion complexes affected the micelle size and stabilized the hydrogels. The rheological properties of solution and hydrogels were measured. The viscosity of hydrogel was enhanced markedly, to about 90 times higher than that of Fc-F127-Fc solution at the same concentration. Due to the coactions of PPO aggregation and Fc-β-CD inclusion, the gelation temperature of hydrogel was lower than that of Fc-F127-Fc solution. The reversible gel-sol transition and multi-sensitive supramolecular hydrogels may potentially be used in injectable hydrogel for drug delivery.
Co-reporter:Heng Chen and Jie Kong
The Journal of Physical Chemistry B 2014 Volume 118(Issue 12) pp:3441-3450
Publication Date(Web):March 2, 2014
DOI:10.1021/jp411888p
Terminal index (TI) was presented as a new characteristic parameter for quantitative description of branched and cyclic topology of highly branched soluble polymers derived from A2 + B3 stepwise polymerization. TI is defined as the ratio of terminal units of an A2 + B3 type highly branched polymer to those in its perfect hyperbranched counterpart. TI is concisely represented as T/(D + L), which can be conveniently calculated from a quantitative NMR spectrum. The model of soluble A2 + B3 type polymers is suggested as an intermediate between multicyclic polymers and perfect hyperbranched polymers. The TI ranges between 0 and 1 where a higher TI indicates a perfect hyperbranched topology while a low TI indicates a multicyclic structure. The analysis of soluble A2 + B3 type polyesters and polycarbosilanes as model polymers demonstrates that TI as a more precise parameter, along with degree of branching, can be generally applied to understand the fine topology of highly branched polymers derived from A2 + B3 polymerization.
Co-reporter:Jie Kong, Minmin Kong, Xiaofei Zhang, Lixin Chen, and Linan An
ACS Applied Materials & Interfaces 2013 Volume 5(Issue 20) pp:10367
Publication Date(Web):September 23, 2013
DOI:10.1021/am403464e
In this contribution, we report a novel strategy for the synthesis of nanocrystal-containing magnetoceramics with an ultralow hysteresis loss by the pyrolysis of commercial polysilazane cross-linked with a functional metallopolymer possessing hyperbranched topology. The usage of hyperbranched polyferrocenylcarbosilane offers either enhanced ceramic yield or magnetic functionality of pyrolyzed ceramics. The ceramic yield was enhanced accompanied by a decreased evolution of hydrocarbons and NH3 because of the cross-linking of precursors and the hyperbranched cross-linker. The nucleation of Fe5Si3 from the reaction of iron atoms with Si–C–N amorphous phase promoted the formation of α-Si3N4 and SiC crystals. After annealing at 1300 °C, stable Fe3Si crystals were generated from the transformation of the metastable Fe5Si3 phase. The nanocrystal-containing ceramics showed good ferromagnetism with an ultralow (close to 0) hysteresis loss. This method is convenient for the generation of tunable functional ceramics using a commercial polymeric precursor cross-linked by a metallopolymer with a designed topology.Keywords: cross-linker; hyperbranched; magnetoceramics; polymeric precursors;
Co-reporter:Yingxue Zhou, Xiaodong Fan, Dan Xue, Jianwei Xing, Jie Kong
Reactive and Functional Polymers 2013 73(3) pp: 508-517
Publication Date(Web):March 2013
DOI:10.1016/j.reactfunctpolym.2012.12.001
Co-reporter:Heng Chen, Jie Kong, Wei Tian, and Xiao-Dong Fan
Macromolecules 2012 Volume 45(Issue 15) pp:6185-6195
Publication Date(Web):July 23, 2012
DOI:10.1021/ma300686b
In this contribution, we report a convenient expression of average number of cyclic structures (ANC) and cyclic-average molecular weight (MC) to quantificationally describe the topological defect of intramolecular cyclization in highly branched polymers synthesized via A2 + Bn (n ≥ 3) stepwise polymerization strategy by a combination of nuclear magnetic resonance spectrometry (NMR) and size exclusion chromatography (SEC). The ANC and MC depend on the number ratio of dendritic, linear, terminal units and number-average molecular weight of hyperbranched polymers, which can be derived from NMR and SEC, respectively. The analysis of hyperbranched polycarbosilanes with silicon hydrogen bonds (A) or vinyl groups (B) termini from A2 + B3 approach indicates that the quantificational description of ANC and MC make it easy to well understand intramolecular cyclic structures resulting in a highly branched topology. Regulating the flexibility and rigidness of internal units in A2 monomers is an effective way to control the extent of intramolecular cyclization. Because of the general and convenient nature, the ANC and MC have potential for the quantificational description of intramolecular cyclization, i.e. one type of topological defect, in a variety of hyperbranched polymers synthesized via A2 + Bn strategy.
Co-reporter:Bing-Yang Cao, Yuan-Wei Li, Jie Kong, Heng Chen, Yan Xu, Kai-Leung Yung, An Cai
Polymer 2011 Volume 52(Issue 8) pp:1711-1715
Publication Date(Web):5 April 2011
DOI:10.1016/j.polymer.2011.02.019
Generally polymer bulk structures and nanostructures are thermally insulative. In this study, we show that an improved nanoporous template wetting technique can prepare thermally conductive polymer nanowire arrays. The thermal conductivities of the fabricated high-density polyethylene (HDPE) nanowire arrays with diameters of 100 nm and 200 nm, measured by a laser flash method, are about 2 orders of magnitude higher than their bulk counterparts. The estimated thermal conductivity of a single HDPE nanowire is as high as 26.5 W/mK at room temperature. The high orientation of chains of the HDPE nanowires may arise from the integrative effects of shear rate, vibrational perturbation, translocation, nanoconfinement and crystallization. Findings in this study provide useful strategies on enhancing the intrinsic thermal properties of polymer nanostructures.
Co-reporter:Wei Tian, Xiaodong Fan, Jie Kong, Yuyang Liu, Tao Liu, Yi Huang
Polymer 2010 Volume 51(Issue 12) pp:2556-2564
Publication Date(Web):28 May 2010
DOI:10.1016/j.polymer.2010.04.009
Novel supramolecular system of amphiphilic hyperbranched polymer with hyperbranched poly(β-cyclodextrin) core was designed and synthesized to accomplish a so-called selective encapsulation, where two types of guest molecules can be encapsulated into two types of molecular cavities from β-cyclodextrin (β-CD) and topography structure of hyperbranched polymer, respectively. The double molecular recognition behaviors from β-CD and hyperbranched cavities drive one guest to go into the former, the other guest to the latter. This selective encapsulation was further confirmed via the release profiles and sequences of Levofloxacin lactate (LL) and Phenolphthalein (PP). LL presents a sustained release period followed by an almost non-release stage, while PP releases on a quite slow rate at first, subsequently on the linearly increasing rate. At the early stage, the release of LL dominates in comparison with PP, and then the release rate of PP increases to play a determinate role in the release system. It can be attributed to the existence of two guests in the different molecular cavities with the different microenvironments. The observed selective encapsulation of supramolecular system is a new phenomenon, which is helpful to extend the application of CD-based hyperbranched polymers in supramolecular science and complex drug delivery system.
Co-reporter:Fangfang Chen, Weifeng Zhao, Jingjing Zhang and Jie Kong
Physical Chemistry Chemical Physics 2016 - vol. 18(Issue 2) pp:NaN725-725
Publication Date(Web):2015/09/08
DOI:10.1039/C5CP04218F
Surface molecular imprinting for proteins is an emerging cross-field of molecular imprinting engineering and functional materials. In this contribution, we report a novel design of magnetic two-dimensional molecularly imprinted polymers (2D-MIPs) for the high recognition and separation of proteins. Bovine serum albumin-surface-imprinted polydopamines were prepared on the surfaces of the magnetic Fe3O4–graphene oxide hybrid to form magnetic 2D-MIPs for proteins. The 2D Fe3O4–graphene oxide substrate possesses a dominant surface-to-volume ratio in comparison to 3D spherical substrates with the same volume. These materials are sensitive to a magnetic field and can be easily separated using an external magnet. The binding experimental results of bovine serum albumin on magnetic 2D-MIPs and real sample analysis demonstrated the high recognition specificity, selectivity, accessibility and convenient separation of 2D-MIPs for template protein. The design and synthesis of magnetic 2D-MIPs provide a new perspective for the surface molecularly imprinted materials with potential in the recognition and separation of proteins.
Co-reporter:Qingfu Ban, Ting Bai, Xiao Duan and Jie Kong
Biomaterials Science (2013-Present) 2017 - vol. 5(Issue 2) pp:NaN210-210
Publication Date(Web):2016/12/19
DOI:10.1039/C6BM00600K
In the cutting-edge field of cancer therapy, noninvasive photothermal therapy (PTT) has received great attention because it is considered to overcome the drawbacks of conventional surgery, radiotherapy and chemotherapy of severe body injuries and side effects on the immune system. The construction of PTT therapeutic and theranostic nanoplatforms is the key issue in achieving tumor targeting, imaging and therapy in a synergetic manner. In this review, we focus on the recent advances in constructing PTT therapeutic and theranostic nanoplatforms by integrating nanomaterials and functional polymers. The noninvasive photothermal cancer therapy mechanism and achievement strategies of PTT therapeutic and theranostic nanoplatforms are presented as well as the innovative construction strategies and perspectives for the future. Owing to their high tumor ablation efficiency, biological availability and low- or non-toxicity, PTT therapeutic and theranostic nanoplatforms are promising and emerging in medicine and clinical applications.
Co-reporter:Jiang Guo, Haixiang Song, Hu Liu, Chunjia Luo, Yanrong Ren, Tao Ding, Mojammel A. Khan, David P. Young, Xinyu Liu, Xin Zhang, Jie Kong and Zhanhu Guo
Journal of Materials Chemistry A 2017 - vol. 5(Issue 22) pp:NaN5344-5344
Publication Date(Web):2017/04/20
DOI:10.1039/C7TC01502J
Epoxy nanocomposites reinforced with polypyrrole functionalized nano-magnetite (Fe3O4–PPy) showed significantly enhanced electromagnetic wave absorption performance and flame retardancy. The Fe3O4–PPy nanocomposites were prepared by the surface initiated polymerization method. The epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites possess a minimum reflection loss (RL) value of −35.7 dB, which is much lower than that of either epoxy/(7.5 wt%)PPy nanocomposites with a minimum RL value of −11.0 dB or epoxy/(30.0 wt%)Fe3O4 with a minimum RL value of −17.8 dB at the same thickness (1.7 mm). Meanwhile, the bandwidth of epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites for RL < −10 dB and RL < −20 dB is 4.0 GHz and 0.8 GHz, respectively. The increased interface area, eddy current loss and anisotropic energy are essentially important to achieve higher reflection loss and broader absorption bandwidth for epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites. Moreover, the significantly reduced flammability was observed in the epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites compared with pure epoxy. The total heat release of epoxy/(30.0 wt%)Fe3O4–PPy nanocomposites decreased from 25.5 kJ g−1 of pure epoxy to just 12.3 kJ g−1. The tensile strength of the epoxy nanocomposites was reported as well. These new nanocomposites with an enhanced electromagnetic wave absorption property and flame retardancy possess great potential for safer electromagnetic wave absorbers in the electronic industry to satisfy stringent industrial standards.
Co-reporter:Xiaofei Zhang, Lixin Chen, Jin Yun, Xiaodong Wang and Jie Kong
Journal of Materials Chemistry A 2017 - vol. 5(Issue 22) pp:NaN10997-10997
Publication Date(Web):2017/04/26
DOI:10.1039/C7TA01156C
In this work, we present, for the first time, the synthesis and characterization of magnetic Si–C–Fe hybrid microspheres and their catalytic performance in room temperature reduction of 4-nitrophenol as a representative sustainable process for converting environmental pollutants to fine chemicals. The ferrocene-modified polydivinylbenzene (Fc-PDVB) precursor was synthesized by Pt-catalyzed hydrosilylation between the residual vinyl groups on the PDVB surface and 1,1′-bis (dimethylsilyl)ferrocene, where further pyrolysis led to the formation of Fe nanocrystal-containing Si–C–Fe hybrid microspheres. The precursor and hybrid microspheres were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR), BET surface area/porosity, powder X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), magnetic properties and MAS solid-state NMR measurements. The ultimate microspherical catalyst exhibited nano- and meso-pores, a high specific surface area (i.e., 347.9 m2 g−1) and good ferromagnetic properties. Efficient catalytic activity (TOF: 0.163 s−1), 100% selectivity (to 4-aminophenol) and excellent reusability (with easy separation) have been delivered. The achieved microspheres outperform a number of nanomaterials such as supported noble metal particles, composites, monoliths and sheets. We have confirmed by DFT calculations that the activation of 4-nitrophenol via its weak non-covalent interaction with the sp2 carbon domain of Si–C–Fe hybrid microspheres contributed to the superior performance which can be extended to a range of nitrobenzenes.
Co-reporter:Junwei Gu, Wencai Dong, Yusheng Tang, Yongqiang Guo, Lin Tang, Jie Kong, Sruthi Tadakamalla, Bin Wang and Zhanhu Guo
Journal of Materials Chemistry A 2017 - vol. 5(Issue 28) pp:NaN6936-6936
Publication Date(Web):2017/05/12
DOI:10.1039/C7TC00222J
In this contribution, we present a new strategy for the fabrication of modified cyanate ester resins combined with ultralow dielectric properties, improved mechanical properties and high thermal and dimensional stabilities. The fluoride-containing compound 2-((3-(trifluoromethyl)phenoxy)methyl)oxirane (TFMPMO), synthesized from m-(trifluoromethyl)phenol (TFMP) and epichlorohydrin (ECH), was used to modify bisphenol A dicyanate ester (BADCy) resins via copolymerization reaction. The BADCy resin modified with 15 wt% TFMPMO presented ultralow dielectric constant (ε, 2.75) and dielectric loss tangent values (tanδ, 6.7 × 10−3), high mechanical properties (impact strength of 15.4 kJ m−2 and flexural strength of 141.0 MPa), and superior thermal and dimensional stability (THeat-resistance index of 206 °C and coefficient of thermal expansion of 6.4 × 10−5), and it possesses great potential application in radomes and antenna systems of aircraft.
![Tricyclo[7.3.3.15,11]heptasiloxane, 3,7,14-tris[[dimethyl[3-(2-oxiranylmethoxy)propyl]silyl]oxy]-1,3,5,7,9,11,14-heptakis(2-methylpropyl)-](/data/chemimg/3783000/927187-62-0.png)
![Tricyclo[7.3.3.15,11]heptasiloxane, 3,7,14-tris[[dimethyl[3-(2-oxiranylmethoxy)propyl]silyl]oxy]-1,3,5,7,9,11,14-heptakis(2-methylpropyl)-](/data/chemimg/3783000/927187-62-0_b.png)
![Benzoic acid, 4-(chlorocarbonyl)-, 1,1'-[1,3,5,7,9,11,13,15-octakis(2-methylpropyl)tetracyclo[9.5.1.13,9.15,15]octasiloxane-7,13-diyl] ester](/data/chemimg/3782900/1637736-00-5.png)
![Benzoic acid, 4-(chlorocarbonyl)-, 1,1'-[1,3,5,7,9,11,13,15-octakis(2-methylpropyl)tetracyclo[9.5.1.13,9.15,15]octasiloxane-7,13-diyl] ester](/data/chemimg/3782900/1637736-00-5_b.png)
![Benzoyl chloride, 4,4'-[[4,6-bis[[(1,1-dimethylethyl)dimethylsilyl]oxy]-1,3-phenylene]bis(iminocarbonyl)]bis-](/data/chemimg/3783900/2094490-64-7.png)
![Benzoyl chloride, 4,4'-[[4,6-bis[[(1,1-dimethylethyl)dimethylsilyl]oxy]-1,3-phenylene]bis(iminocarbonyl)]bis-](/data/chemimg/3783900/2094490-64-7_b.png)
![Borane, bis[1-(dichloromethylsilyl)ethyl][2-(dichloromethylsilyl)ethyl]-](http://img.cochemist.com/ccimg/269400/269397-18-4.png)
![Borane, bis[1-(dichloromethylsilyl)ethyl][2-(dichloromethylsilyl)ethyl]-](http://img.cochemist.com/ccimg/269400/269397-18-4_b.png)
![Poly[oxy(ethenylmethylsilylene)]](http://img.cochemist.com/ccimg/28400/28323-46-8.png)
![Poly[oxy(ethenylmethylsilylene)]](http://img.cochemist.com/ccimg/28400/28323-46-8_b.png)
