Jie Yang

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Name: 龙盛如
Organization: Sichuan University
Department: Institute of Materials Science and Technology
Title:

TOPICS

Co-reporter:Jiehong Lu;Guangming Yan;Gang Zhang
Journal of Polymer Research 2017 Volume 24( Issue 10) pp:152
Publication Date(Web):01 September 2017
DOI:10.1007/s10965-017-1317-1
A series of poly(arylene ether)s with pendant cyclohexyl units had been prepared by solution polycondensation of 4,4′-cyclohexane-1,1′-diyldiphenol (CHDP) and 4,4′-difluorobenzophenone (DFBP) (or 4,4′-difluorodiphenylsulfone (DFDPS)). The inherent viscosities of obtained poly(arylene ether)s were in the range of 0.49–0.97 dLg−1. They were found to have high glass transition temperatures (Tg) of 158–208 °C, and good thermal stability with 5% weight-loss temperature (T5%) of 442–484 °C. The tensile test and dynamic mechanical analysis results indicate the good mechanical properties of poly(arylene ether)s. Their Young’s Mdoulus were found to be 2.2–2.3 GPa, tensile strengths were 81.0–97.7 MPa, storage mdoulus were over 1.5 GPa even near glass transition temperature. The complex viscosities of the resultant polymers melt maintained a narrow range of 308–313 Pas at 260 °C or 2700–4600 Pas at 340 °C during the testing time. That indicates the resultant resins have good melt flowability and stability. In addition, these poly(arylene ether)s were found to have good solubility in various solvents such as CHCl3, THF, NMP, DMAc, DMI, etc., and have good optical transmittance (>80%) at 450 nm. It suggests that the obtained poly(arylene ether)s not only can be processed by melt method, but also can be applied with solution method easily, and can be applied to tough and transparent films.
Co-reporter:Hao-hao Ren, Dong-xia Xu, Guang-ming Yan, Gang Zhang, Xiao-jun Wang, Sheng-ru Long, Jie Yang
Composites Science and Technology 2017 Volume 146(Volume 146) pp:
Publication Date(Web):7 July 2017
DOI:10.1016/j.compscitech.2017.03.021
The aim of this study was synthesis of the polyphenylene sulfide (PPS) containing carboxyl unit and investigation of the effect of modified PPS used as compatibilizer on the interfacial micromechanical properties of carbon fiber (CF) reinforced PPS composites. A series of copoly(1,4-phenylene sulfide)-poly(2,5-phenylene sulfide acid) (PPS-COOH)s containing different proportions of carboxyl units in the side chain were synthesized by the reaction of dihalogenated monomer and sodium sulfide via nucleophilic substitution polymerization under high pressure. According to the results of FT-IR, DSC, TGA, mechanical test and contact angle test, all of the copolymers were found to have analogous structure and improved hydrophilic property comparing with neat PPS. There was a good physical compatibility between the modified PPS and the pure PPS. The microbond test (measuring apparent interfacial shear strength (τapp) of the composite) and scanning electron microscopy (SEM) also showed that the optimized PPS-COOH (7.5) can be used to improve the micro-mechanical properties and interfacial bonding between CF and PPS matrix. The maximum τapp of 10%PPS-COOH (7.5)/PPS/CF composite was 49.1 MPa, which had increased 36.0% comparing with that of the pure PPS/CF composite (36.1 MPa).
Co-reporter:Gang Zhang, Guang-Ming Yan, Hao-Hao Ren, Yan Li, Xiao-Jun Wang and Jie Yang  
Polymer Chemistry 2016 vol. 7(Issue 1) pp:44-53
Publication Date(Web):04 Nov 2015
DOI:10.1039/C5PY01634G
Semi-aromatic monomers containing a cyclohexane unit, prepared using a facile interfacial reaction method from 1,4-cyclohexanediamine (trans- or cis-) and 4-fluorobenzoyl chloride (4-FBC) at room temperature, were reacted with 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BHPPE) to afford two kinds of semi-aromatic polyamide (BH-trans-BFCD and BH-cis-BFCD) in this work. An investigation of thermal properties confirmed high glass transition temperatures (Tg) of 224–265 °C and good thermal stability with initial degradation temperatures (Td) of 445 to 450 °C for the synthesized semi-aromatic polyamides, which were determined by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) characterization. It was found that the properties (thermal and mechanical) of BH-trans-BFCD, containing a trans-conformation, were much better than those of BH-cis-BFCD, containing a cis-conformation. Comparing the thermal stability of the resultant semi-aromatic polyamides with a commercial product, PA6T-Dupont, the prepared polyamides treated at 220 °C for 7 h displayed a slightly reduced tensile strength as well as a smaller change in color. According to rheological testing, they were found to have better melt flowability (complex viscosities ranged from 210 to 3070 Pa s at 310 °C to 360 °C). Additionally, their thermal degradation kinetics and the thermal pyrolysis mechanism of these semi-aromatic polyamides were investigated by thermogravimetric analysis and Pyrolysis/Gas Chromatography/Mass (Py-GC/MS) analysis, which further indicated their higher thermal stability and processability.
Co-reporter:Guang-ming Yan, Gang Zhang, Hao-hao Ren, Yan Li and Jie Yang  
RSC Advances 2016 vol. 6(Issue 80) pp:76490-76497
Publication Date(Web):08 Aug 2016
DOI:10.1039/C6RA13021F
Two new difluorobenzamide monomers, N,N′-bis(4-fluorobenzamide)dicyclohexyl methane and N,N′-bis(4-fluorobenzamide)-3,3′-dimethyl dicyclohexyl methane were synthesized from 4,4′-diamino dicyclohexyl methane and bis-(3-methyl-4-aminocyclohexyl)-methane with 4-fluorobenzoyl chloride through a facile interfacial reaction. Both of the monomers were used to prepare semiaromatic polyamides by a nucleophilic polycondensation reaction with 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BHPPE). The resultant semiaromatic polyamides were characterization by FT-IR, differential scanning calorimetry, thermogravimetric analysis, dynamic thermomechanical analysis etc. These semiaromatic polyamides were found to have excellent thermal properties: the glass transition temperature (Tg) of Ph-DCM and Ph-MCM was 217.2 °C and 236.9 °C, and the 5% weight-loss temperature (T5%) was 442.3 °C and 429.8 °C, respectively. The tensile test and dynamic thermo-mechanical analysis indicates that the resultant polyamides have good mechanical properties. The rheological testing showed that when the temperature increased from 290 °C to 350 °C, the complex viscosities of Ph-DCM decreased from 8.7 to 2.9 kPa s and the complex viscosities of Ph-MCM dropped from 20.8 to 0.9 kPa s. The results indicate that these semiaromatic polyamides have good melt flowability and are suitable for the melting processing. In particular, the polyamide with pendent methyl groups was found to have lower complex viscosities than that with no pendent methyl groups.
Co-reporter:Fang Qiu;Minle Peng;Zhimei Wei;Xiaojun Wang
Journal of Applied Polymer Science 2016 Volume 133( Issue 9) pp:
Publication Date(Web):
DOI:10.1002/app.43066

ABSTRACT

A novel kind of sulfonated polyethersulfonephenylethane (SPESPE) was successfully synthesized firstly in this work. Then the SPESPE was introduced in polyethersulfone (PES) microspheres prepared by the electrospraying technique. The microspheres were applied to adsorbing bisphenol A (BPA) from its aqueous solution. Compared with the PES microspheres, the adsorption capacity of PES/SPESPE microspheres for BPA was increased significantly. Furthermore, the adsorption capacity of PES/SPESPE microspheres was enhanced by increasing the amounts of SPESPE in the microspheres. The pH of solution had influence on the adsorption capacity of PES/SPESPE microspheres. The kinetic data of adsorption were found to follow pseudo-second-order model. The Freundlich isotherm model was suitable to describe the equilibrium adsorption data. The microspheres also showed excellent regeneration and reuse ability. These results indicated that the PES/SPESPE microspheres have the potential to be used in environmental application. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43066.

Co-reporter:Yan Li;Gang Zhang;Xiaojun Wang;Zhi-Min Li
Polymer Engineering & Science 2016 Volume 56( Issue 1) pp:44-50
Publication Date(Web):
DOI:10.1002/pen.24190

Poly(ether ether sulfone) (PEES) containing semi-aromatic polyamides with methylene units and ether linkage were synthesized through the copolymerization of m-dihydroxybenzene, 4,4-dichlorodiphenylsulfone (DCDPS) and 1,6-N, N′-bis(4-fluorobenzamide) hexane (BFBH) by the method of nucleophilic polymerization. The inherent viscosities of the resultant different proportion of copolymers were in the range of 0.39–0.78 dL/g. These copolymers were found to have excellent thermal properties with glass transition temperatures (Tg) of 121–177°C, and initial degradation temperatures (Td) of 417.5–432.5°C. These copolymers showed good mechanical properties with tensile strengths of 45–83 MPa, storage modulus of 1.8–2.6 GPa. The complex viscosities of pure Poly(ether ether sulfone) (PEES) was in the range of 176,000–309.8 Pas from 0.01 to 100 Hz, the complex viscosities of the copolymers decreased significantly with the increase of semi-aromatic amide content, the copolymers of 20% decreased from 4371 to 142.4 Pas (from 0.01 to 100 Hz), and the copolymers of 70% dropped from 634.6 Pas to 55.97 Pas (from 0.01 Hz to 100 Hz). All copolymers exhibited non-Newtonian and shear-thinning behavior. These results suggested the resultant copolymers possess better melt flowability that is beneficial for the materials’ melt processing. POLYM. ENG. SCI., 56:44–50, 2016. © 2015 Society of Plastics Engineers

Co-reporter:Guang-ming Yan;Zhi-min Li;Gang Zhang;Hao-hao Ren
Journal of Polymer Research 2016 Volume 23( Issue 3) pp:
Publication Date(Web):2016 March
DOI:10.1007/s10965-016-0948-y
High-molecular-weight poly(p-arylene sulfide ketone) (PPSK) was prepared by nucleophilic substitution reaction of 4,4’-diflurobenzophenone (DFBP) and sodium sulfide in the compound solvents of diphenyl sulfone (DPS) and 1,3-dimethyl-2-imidazolidinone (DMI) with catalysts under elevated temperature. The inherent viscosity (ηint) of the PPSK synthesized was 0.703 dl/g. PPSK was characterized by Fourier-transform infrared spectroscopy, elemental analysis, x-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. It was found that the polymer had excellent thermal properties: glass transition temperature (Tg) was 142.8 °C, melting temperature (Tm) was 362.3 °C. Under nitrogen atmosphere, 5 % (T5%) and 10 % (T10%) weight-loss temperatures were about 498.5 °C and 526.2 °C, respectively, while in the air the T5% and T10% were about 517 °C and 535.8 °C, respectively. The PPSK was found to be a semi-crystalline polymer, as confirmed by XRD. The polymer was insoluble in any solvent except concentrated sulfuric acid at room temperature. A series of the PPSK separating membranes were prepared by dissolving PPSK to concentrated sulfuric acid. The fluxes and the porosities of the separating membranes were in the range of 230–43 L/(m2 · h) and 77.7-84.7 %, respectively. At the same time, these separating membranes showed moderate tensile strength of 1.02-1.88 MPa.
Co-reporter:Yaqi Yang;Wenhui Yu;Hongji Duan;Yaqing Liu;Xiaojun Wang
Journal of Polymer Research 2016 Volume 23( Issue 9) pp:
Publication Date(Web):2016 September
DOI:10.1007/s10965-016-1093-3
Reinforcing and toughening poly (phenylene sulfide) (PPS) with rigid SiO2 nano-particles was realized simultaneously under the suitable thermodynamic state of PPS, and the key issue about the effect of matrix/filler interaction was also demonstrated. The strong matrix/filler interaction realized by grafting reactive groups onto nanoparticles was beneficial for stress transfer and thus in favor of the increase in tensile strength of PPS. Meanwhile, this interaction provided nanoparticles with certain mobility to move with molecular chains and align along the tensile direction when T > Tg of PPS, thus the nanoparticles could significantly improve the tensile toughness of PPS according to the energy dissipation mechanism. Consequently, the tensile strength and elongation to break values of PPS increased to 59.0 MPa and 112.1 % from the initial values of 48.0 MPa and 78.5 % by adding 1 wt% grafted SiO2 nano-particles. The work provided a promising method to reinforce and toughen rigid-chain polymer simultaneously and prepare high-performance PPS nanocomposites.
Co-reporter:Gang Zhang, Yu-xuan Zhou, Yan Li, Xiao-Jun Wang, Sheng-Ru Long and Jie Yang  
RSC Advances 2015 vol. 5(Issue 62) pp:49958-49967
Publication Date(Web):21 May 2015
DOI:10.1039/C5RA04116C
The difluoro-substituted monomer, N,N′-bis(4-fluorobenzoyl) isophorone diamine (BFID), was prepared via an interfacial reaction from isophorone diamine and 4-fluorobenzoic chloride. It was then reacted with hydroquinone (or resorcinol, 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BHPPE)) to yield a series of semi-aromatic polyamides. For the synthesized semi-aromatic polyamides, differential scanning calorimetry and thermogravimetric analysis confirmed their high glass transition temperatures (Tg), which were between 217 and 239 °C, and good thermal stability with initial degradation temperatures (Td) in the range of 425–430 °C. Tensile test and dynamic mechanical analysis (DMA) results revealed the good mechanical properties of the semi-aromatic polyamides at ambient temperature and even at 200 °C. Rheological characterization displayed complex viscosities at 310 °C for the semi-aromatic polyamide in the range of 990–1350 Pa s, which suggests that they are suitable for melt processing. Better solubility properties for the resultant semi-aromatic polyamides compared to commercial ones were also found. All the results indicated the good processability of the synthesized semi-aromatic polyamides. In addition, they were found to have almost identical optical transmittance (Tran%: 83–85% at 450 nm) as polycarbonate (PC), in the UV-visible region.
Co-reporter:Zhimei Wei, Minle Peng, Fang Qiu, Xiaojun Wang, Shengru long and Jie Yang  
RSC Advances 2015 vol. 5(Issue 53) pp:42305-42310
Publication Date(Web):22 Apr 2015
DOI:10.1039/C5RA06446E
Conductive electrospun fibers have attracted widespread interest in the field of electromagnetics. However, the problem of how to effectively improve the electrical conduction of electrospun fibers has still not been adequately addressed. In this study, a new, simple and effective method was introduced to significantly improve the conductive properties of fibers. PES/PVA fibers with previous addition of 20 wt% PVA were chosen as a matrix due to the large parallel porous structure. The carbon nanotubes (CNTs) were first absorbed by the PES/PVA fibers, and then a thin polymer/CNTs composite layer was self-formed on the surface of the porous fibers by vapor treatment. Most importantly, a CNTs network structure was also formed in this vapor process, which easily gave the porous fibers a significant enhancement in conductivity with only a small amount of CNTs. Electrical conduction tests showed that the conduction of the fibers increased with increasing CNT content, and attained the maximum value when the amount of CNTs was around 7 wt%. The adsorption time and the DMSO vapor treatment time were optimized to obtain the best thin polymer/CNT composite layers. The surface microstructure of the composite layer was observed using scanning electron microscopy (SEM) and TGA. The results showed that this novel, powerful method could potentially be used to prepare novel types of conductive polymer fibers.
Co-reporter:Shushan Yuan;Juan Wang;Xiaojun Wang;Shengru Long;Gang Zhang
Polymer Engineering & Science 2015 Volume 55( Issue 12) pp:2829-2837
Publication Date(Web):
DOI:10.1002/pen.24174

Poly(arylene sulfide sulfone) (PASS) is a kind of newly developed polymeric membrane material which has excellent mechanical strength, thermal stability, and solvent resistance. And, it would be a potential material for high temperature ultrafiltration and organic solvent filtration. In this article, PASS hybrid ultrafiltration membrane with improved antifouling property was prepared by mixing TiO2 nanoparticles which were grafted with polyacrylic acid (PAA). These membranes were prepared by a phase inversion technique and their separation performance and antifouling property of the prepared membranes were investigated in detail by SEM, FTIR, EDS, contact angle goniometry, filtration experiments of water, and BSA solution. The results shown that the TiO2-g-PAA nanoparticles dispersed well in membrane matrix, the hydrophilicity of the membranes prepared within TiO2-g-PAA nanoparticles have been improved and these membranes exhibited excellent water flux and antifouling performance in separation than that of the pure PASS membranes and PASS membranes with TiO2 nanoparticles. More specifically, among membrane sample M0, M1.5, and MP1.5, MP1.5 which contained 1.5 wt% TiO2-g-PAA exhibited the highest water permeation (190.4 L/m2 h at 100 kPa), flux recovery ratio, and the lowest BSA adsorption amount. POLYM. ENG. SCI., 55:2829–2837, 2015. © 2015 Society of Plastics Engineers

Co-reporter:Kun Zhang, Gang Zhang, Baoying Liu, Xiaojun Wang, Shengru Long, Jie Yang
Composites Science and Technology 2014 Volume 98() pp:57-63
Publication Date(Web):27 June 2014
DOI:10.1016/j.compscitech.2014.04.020
The aim of this study was to investigate the effect of the aminated polyphenylene sulfide (PPS-NH2) used as compatibilizer on the mechanical properties of carbon fiber (CF) reinforced polyphenylene sulfide (PPS) composites. The compatibilizers PPS-NH2 which were synthesized by the condensation polymerization of sodium sulfide (Na2S), p-dichlorobenzene (DCB), and the third active monomer 2,5-dichloroaniline (DCA). Composites with 20 wt% CF, 75 wt% PPS and 5 wt% PPS-NH2 which were synthesized by different mole ratios of Na2S/DCB/DCA were prepared by melt blending and injection molding. According to the results of mechanical properties tests, dynamic mechanical analysis (DMA), microbond test (apparent interfacial shear strength, τapp) and scanning electron microscopy (SEM), the compatibilizers PPS-NH2 could improve the macro-mechanical properties and interfacial bonding between CF and PPS matrix.
Co-reporter:Qingyu Lin, Zhimei Wei, Mingjun Xu, Shuai Wang, Guanghui Niu, Kunping Liu, Yixiang Duan and Jie Yang  
RSC Advances 2014 vol. 4(Issue 28) pp:14392-14399
Publication Date(Web):03 Feb 2014
DOI:10.1039/C3RA47697A
The major application of the laser-induced breakdown spectroscopy (LIBS) technique had been in the analysis of solid samples because the measurement of LIBS for liquid samples experiences some experimental difficulties, such as splashing, a quenching effect, and a shorter plasma lifetime. In the present work, electrospun ultrafine fibers were explored and used for the first time as a solid-phase support to quantify chromium (Cr) and copper (Cu) in aqueous solutions by LIBS. The liquid sample was first transferred to an ultrafine fiber surface, which could minimize the drawbacks of liquid sample analysis with LIBS. Due to the special micro-porous structure, the electrospun ultrafine fibers could hold a larger liquid sample and also the liquid sample was easy to evaporate. On the other hand, as a polymer substrate, the porous electrospun ultrafine fibers contributed to the minimal blank since there was no other unwanted heavy metal matrix that affected the detection during the liquid LIBS analysis. Meanwhile, the large sampling spot to fiber diameter ratio will minimize the potential influence generated in the liquid sample distribution process. With this pre-treated sample technique, the sensitivities of LIBS for liquid samples are improved considerably and the detection limits for Cr and Cu reached 1.8 ppm and 1.9 ppm, respectively. Therefore, the present strategy definitely paves the way for a wider application of LIBS in liquid sample analysis.
Co-reporter:Gang Zhang, Shu-shan Yuan, Zhi-min Li, Sheng-ru Long and Jie Yang  
RSC Advances 2014 vol. 4(Issue 44) pp:23191-23201
Publication Date(Web):15 May 2014
DOI:10.1039/C4RA02829E
Two kinds of high glass temperature poly(arylene ether sulfone)s containing thioether and biphenyl units (PASSs) have been developed. The polymers were prepared by a polycondensation reaction of 4,4′-bis(4-chlorophenylsulfone)biphenyl (BCPSB) and 4,4′-dimercaptodiphenyl sulfone (DMDPS) (or 4,4′-bis(4-mercaptophenylsulfone)biphenyl (BMPSB)). They showed good thermal properties such as a relatively high glass transition temperature of 263–282 °C and a 5% weight-loss temperature (T5%) of 441–445 °C. The water flux and retention rate of the resultant membranes were 0.61–2.48 L m−2 h−1 and 89.47–94.91%, respectively. Interestingly, we found that the corrosion resistance of the membranes had been largely improved with the oxidization treatment. They were even insoluble in NMP, DMSO, concentrated H2SO4, aqua regia and so on, while the polymers without oxidation were soluble or destroyed in above solvents. In addition, we found the water flux of the oxidized membrane was also improved but the retention rate only decreased a little.
Co-reporter:Gang Zhang, Yu-xuan Zhou, Yu Kong, Zhi-min Li, Sheng-Ru Long and Jie Yang  
RSC Advances 2014 vol. 4(Issue 108) pp:63006-63015
Publication Date(Web):07 Nov 2014
DOI:10.1039/C4RA10074C
A series of semiaromatic difluorobenzamide monomers was synthesized by the reaction of diamine and 4-fluorobenzoic chloride using a facile interfacial method. These syntheses were conducted to react the monomers with 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BHPPE), so as to prepare semiaromatic polyamides containing ether units by the method of nucleophilic polycondensation. These had excellent thermal properties with glass transition temperatures (Tg) of 134.4–195.6 °C and initial degradation temperatures (Td) of 405–443 °C. The activation energies of degradation were in the range of 180.1–275.9 kJ mol−1. The resultant polymers can be dissolved in strong polar solvents and supply a tough film with a tensile strength of 89–105 MPa. Also, we found that the complex viscosities of these semiaromatic polyamides ranged from 77 to 688 Pa s at 290 °C. They had the appropriate complex viscosities for melt processing. Moreover, they had much wider processing windows than those of traditional semiaromatic polyamides such as poly(hexamethylene terephthalamide) (PA6T). Interestingly, some of the resultant polymers were found to be naturally self-retardant.
Co-reporter:Dongsheng Li;Zhimin Li;Fei Hu;Shengru Long;Gang Zhang
Polymer Engineering & Science 2014 Volume 54( Issue 9) pp:2013-2022
Publication Date(Web):
DOI:10.1002/pen.23754

A series of sulfonated poly(aryl ether sulfone) copolymers containing phenyl pendant groups with sulfonic acid groups on the backbone were synthesized through condensation polymerization. The degree of sulfonation (DS) of the copolymers was controlled by changing the feed ratios of sulfonated to unsulfonated monomers. Post-crosslink reactions are carried out with 4,4′-thiodibenzoic acid (TDA) as a crosslinker and the carboxylic acid groups in TDA can undergo Friedel–Craft acylation with the phenyls pendent rings in sulfonated poly(arylene ether sulfone)s copolymers to prepare polymer electrolyte membranes for fuel cell applications. The chemical structures of crosslinked and uncrosslinked sulfonated poly(arylene ether sulfone)s copolymers (SPSFs and CSPSFs) were characterized by FTIR, 1H NMR spectra. The thermal and mechanical properties of the membranes were characterized by thermogravimetric analysis and stress–strain test. The dependence of water uptake, methanol permeability, proton conductivity, and selectivity on DS was studied. Transmission electron microscopic observations revealed that SPSFs and CSPSFs membranes form well-defined microphase separated structures. POLYM. ENG. SCI., 54:2013–2022, 2014. © 2013 Society of Plastics Engineers

Co-reporter:Zhi-min Li;Gang Zhang 张刚;Dong-sheng Li 杨杰
Chinese Journal of Polymer Science 2014 Volume 32( Issue 3) pp:292-304
Publication Date(Web):2014 March
DOI:10.1007/s10118-014-1407-z
Highly refractive and transparent polyamides containing thiadiazole units have been developed. These polymers were prepared by a polycondensation reaction of 4,4′-(1,3,4-thiadiazole-2,5-thio) bis(methylene) dibenzoyl chloride (TDTBM-DC) and diamine which contained thioether (-S-) and sulfone units. They showed good thermal stabilities such as a relatively high glass transition temperature of 206–233 °C and a 5% weight-loss temperature (T5%) of 376–395 °C. The optical transmittance of the polymer at 450 nm is higher than 83%. The heterocycle units and plural -S- linkages provide the polymer with a high refractive index of 1.716–1.725 at 633 nm and a low birefringence of 0.003–0.004. Also they showed improved solubility in polar aprotic solvents and could form moderate strength films with tensile strength of 72.8–83.1 MPa and storage modulus of 1.0–1.8 GPa (at 200 °C).
Co-reporter:Min-le Peng;Li-hua Wang;Zhi-mei Wei;Xiao-jun Wang
Chinese Journal of Polymer Science 2014 Volume 32( Issue 10) pp:1390-1399
Publication Date(Web):2014 October
DOI:10.1007/s10118-014-1514-x
The focus of this work is to control the structure of electrosprayed polymer microspheres and then study the effect of different structures on the microspheres’ adsorption properties. Scanning electron microscopy (SEM) coupled with image analysis software was employed to evaluate the size distributions and the structure of microspheres. According to the observation and analysis results, two types of polyethersulfone (PES) porous microspheres (perfect sphere-shaped and collapsed) were prepared via electrospraying technology by adjusting the solvent and polymer molecular weight. The porous PES microspheres can remove bisphenol A (BPA) from its aqueous solution effectively. Compared with collapsed microspheres, the rough microspheres had much higher specific surface area and better mobility in the BPA aqueous solution, so it showed a better adsorption capacity than that of collapsed microspheres. The solvent evaporation rate and the occurrence rate of phase separation significantly affect the structure and morphology of microspheres.
Co-reporter:Zhimei Wei;Quanchao Zhang;Minle Peng;Xiaojun Wang
Colloid and Polymer Science 2014 Volume 292( Issue 6) pp:1339-1345
Publication Date(Web):2014 June
DOI:10.1007/s00396-014-3187-y
The focus of this work was the preparation of hollow ultrafine fibers with a multilayer wall via coaxial electrospinning technology in one step and then studied their drug delivery properties. In this paper, by choosing a suitable dilute hydrophilic polymer solution as the core solution, polyethersulfone (PES) hollow ultrafine fibers with two different layers wall (porous structure layer and dense smooth layer) were formed during coaxial electrospinning process in one step. They showed good drug delivery capacity when curcumin was used as the model drug. There were much larger delivery amounts, more stable release rate, and higher utilization rate of PES hollow ultrafine fibers with a multilayer wall to curcumin than that of PES porous ultrafine fibers. Compared with porous ultrafine fibers, hollow ultrafine fibers with two different layers wall were more suitable to be used as drug delivery materials. Besides, between the two hollow ultrafine fibers with two different layers wall mentioned in this paper, there was much better drug delivery capacity for the hollow fibers produced with the core solution of PVA/DMSO. These results showed that PES hollow ultrafine fibers with two different layers wall have the potential to be used as the drug delivery materials.
Co-reporter:Yaqi Yang, Hongji Duan, Shouyu Zhang, Pengfei Niu, Gang Zhang, Shengru Long, Xiaojun Wang, Jie Yang
Composites Science and Technology 2013 Volume 75() pp:28-34
Publication Date(Web):11 February 2013
DOI:10.1016/j.compscitech.2012.11.006
We for the first time report a novel method to achieve the morphology control of two kinds of dimensional different nanofillers, the platelike nanoclay and globelike SiO2, by using their “filler to filler” interaction in poly (phenylene sulfide) (PPS). The strong interaction between layered nanoclay and rigid SiO2 is obtained by their different response to shear flow in PPS melt processing. As a result, the exfoliation structure of nanoclay and well-dispersed nano-SiO2 are realized simultaneously. With this successful morphology control, the reinforcement effect of nanofillers in PPS is improved with very little addition. Moreover, with the restriction of exfoliated clay and nano-SiO2 particles, the mobility of PPS molecular chains is confined, leading to the significant change in crystalline behaviors of PPS.
Co-reporter:Gang Zhang, Xiu-jing Xing, Dong-sheng Li, Xiao-jun Wang, and Jie Yang
Industrial & Engineering Chemistry Research 2013 Volume 52(Issue 47) pp:16577-16584
Publication Date(Web):October 22, 2013
DOI:10.1021/ie401750e
Two kinds of aromatic polyesters containing thioether units had been prepared through the reaction of 4,4′-thiodibenzoyl chloride (T-DC) (or 4,4′-bis(4-chloroformylphenylthio)benzene (BPBDC)) and 1,1-bis(4-hydroxyphenyl)-1-phenylethane (BHPPE) by the method of interfacial polycondensation. These polyesters showed good solubility, and could afford tough films with tensile strengths of 103.6–108.3 MPa. The glass transition temperature (Tg) of these polyesters ranged from 189.8 to 235.6 °C and initial degradation temperatures (Td) were 450–454 °C. The activation energies of degradation were in range of 156.6–160.3 KJ/mol. The limiting oxygen indexes (LOIs) of these polyesters ranged from 37 to 39, and UL-94 V-0 rating could achieve via this approach. The thermal degradation kinetics and thermal pyrolysis mechanism of these polyesters was studied by thermogravimetric analysis and Py-GC/MS analysis, respectively.
Co-reporter:Guangshun Huang;Suixin Zhang;Dongsheng Li;Meilin Zhang;Gang Zhang
Polymer International 2013 Volume 62( Issue 3) pp:411-418
Publication Date(Web):
DOI:10.1002/pi.4324

Abstract

Aromatic polyamides containing thioether units were synthesized by interfacial polycondensation of 4,4′-thiodibenzoyl chloride (or 4,4′-bis(4-chloroformylphenylthio)benzene) with aromatic diamines containing a nitrile unit. Their structure was established using 1H NMR and Fourier transform infrared spectroscopy. The inherent viscosities of the polyamides prepared with optimum synthesis conditions were in the range 0.71–0.84 dL g−1. These polyamides showed excellent thermal properties with glass transition temperatures of 210.5–219.6 °C, melting temperatures of 313.8–315.0 °C and initial degradation temperatures of 440–459 °C. They could be processed by melting due to their relatively wide processing window. Their tensile strengths were 71.3–79.1 MPa, water absorption was 0.17–0.22 wt%, and melt flowability was in the range 64.5 to 315.2 Pa s and 68.5 to 422.3 Pa s at different shear rates. At the same time, they were soluble in aprotic solvents such as N-methyl-2-pyrrolidone, dimethylformamide and dimethylsulfoxide. The results suggest that these aromatic polyamides containing thioether units represent a promising type of heat-resistant and processable engineering plastic. © 2012 Society of Chemical Industry

Co-reporter:Baoying Liu, Zhao Liu, Xiaojun Wang, Gang Zhang, Shengru Long, Jie Yang
Polymer Testing 2013 Volume 32(Issue 4) pp:724-730
Publication Date(Web):June 2013
DOI:10.1016/j.polymertesting.2013.03.020
Co-reporter:Gang Zhang;Dong-ting Bai;Dong-sheng Li;Sheng-ru Long;Xiao-jun Wang
Polymer International 2013 Volume 62( Issue 9) pp:1358-1367
Publication Date(Web):
DOI:10.1002/pi.4431

Abstract

Two kinds of monomers containing thioether units 4,6-bis(4-chloroformylphenylthio)pyrimidine (BPPM-DC) and 3,6-bis(4-chloroformylphenylthio)pyridazine (BPPD-DC) were synthesized by two steps and were reacted with diamine-containing thioether (−S–) and sulfone units to prepare a kind of polyamide containing heterocycles and high contents of thioether groups. These polyamides had good optical properties, including an optical transmittance of the aromatic polyamide film at 450 nm that was higher than 87%. Additionally, the pyridazine, pyrimidine and the large quantity of thioether units provided the polymers with high refractive indices of 1.722–1.732 and low birefringences of 0.004–0.006. These polyamides were also found to have good thermal properties. They showed improved solubility in polar aprotic solvents and could form tough films with a tensile strength of 79.2–112.3 MPa and a storage modulus of 1.4–2.4 GPa (at 200 °C).© 2013 Society of Chemical Industry

Co-reporter:Gang Zhang;Yan Zhang;Dong-sheng Li;Guang-shun Huang;Xiao-jun Wang
Polymer Bulletin 2013 Volume 70( Issue 3) pp:789-807
Publication Date(Web):2013 March
DOI:10.1007/s00289-012-0829-4
A series of processable semi-aromatic polyamides containing thioether and methylene units were synthesized through the reaction of 4,4′-thiobis(methylene)dibenzoyl chloride and aliphatic diamine by the method of interfacial polycondensation. These polyamides had excellent thermal properties with glass transition temperatures (Tg) of 104.3–130.6 °C, melting temperatures (Tm) of 300.3–303.8 °C, and initial degradation temperatures (Td) of 405.2–410.3 °C. They had wider processing windows than traditional semi-aromatic polyamides (such as PA6T can not be processed by melting) and can be processed by melting method. They had better tensile strengths of 57.6–64.1 MPa, low-temperature mechanical properties, low water absorption of 0.19–0.27 %, low dielectric constants of 3.11–3.95 at 100 kHz, and better melt flowability properties of 232–60.7, 301.9–78.8, and 423.1–83.6 Pa s under a shear rate ranging from 20 to 1,170 s−1, respectively. In addition, these polyamides showed good corrosion resistance, they did not dissolve in solvents such as NMP, DMSO, hydrochloric acid (6 mol/l), and solution of NaOH (1 mol/l) and so on.
Co-reporter:Yaqi Yang;Hongji Duan;Gang Zhang;Shengru Long
Journal of Polymer Research 2013 Volume 20( Issue 7) pp:
Publication Date(Web):2013 July
DOI:10.1007/s10965-013-0198-1
In this work, we compare the tensile behaviors of two kinds of PPS samples, the mould temperature control sample and thermal curing sample, which undergoing different thermal histories. Based on the SAXS and WAXD results, the crystal structure of PPS is not destroyed in stretching due to its higher Tg. However, the maximum stress value of thermal curing sample is higher than that of mould temperature control sample, though the contribution of crystal phases are the same since their same crystallinity and grain size. The result indicates that the stress of PPS is not only decided by crystal phase (crystallinity) but amorphous phase: the crystal structures carry most part of the stress in stretching process, and the restricted amorphous chains could also carry partial tensile stress. Correlating the possible structure change with mechanical property, it is reasonable to believe higher entanglement density of molecular chains in amorphous phase could lead to more restricted chains, thus giving a higher stress value to thermal curing sample. The theoretical model is proposed to explain the correspondence between micro-structure and macroscopical performance.
Co-reporter:Gang Zhang, Hao-hao Ren, Dong-sheng Li, Sheng-ru Long, Jie Yang
Polymer 2013 Volume 54(Issue 2) pp:601-606
Publication Date(Web):24 January 2013
DOI:10.1016/j.polymer.2012.12.008
A highly refractive and transparent poly(arylene sulfide sulfone) (PASS) containing pyrimidine (or pyridazine) unit has been developed. The polymer was prepared by a polycondensation reaction of 4,4′-dimercaptodiphenyl sulfone (DMDPS) and 4,6-dichloropyrimidine (DCPM) (or 3,6-dichloropyridazine (DCPD)). They showed good thermal stabilities such as a relatively high glass transition temperature of 193–202 °C and a 5% weight loss temperature (T5%) of 370–372 °C. The optical transmittance of the polymer at 450 nm is higher than 81%. The heterocycles unit and plural –S– linkages provides the polymer with a high refractive index of 1.737–1.743 at 633 nm and a low birefringence of 0.003–0.004.
Co-reporter:Gang Zhang;Jiangjun Hu;Huiwen Yang;Xiaojun Wang;Shengru Long
Polymer International 2012 Volume 61( Issue 5) pp:800-809
Publication Date(Web):
DOI:10.1002/pi.4142

Abstract

4,4′-Bis(4-chloroformylphenylthio)benzene was synthesized in two steps and was reacted with diamine-containing thioether and amide units to prepare a polyamide containing high contents of thioether groups. The intrinsic viscosities of the polyamides were 0.76–0.87 dL g−1. These polyamides had excellent thermal properties, with glass transition temperatures of 234.8–269 °C and initial degradation temperatures of 461–469.7 °C. They showed improved solubility in polar aprotic solvents and could form moderate strength films with a tensile strength of 75.2–111.6 MPa and storage modulus of 1.0–1.3 GPa (at 220 °C). These polymer films also had good optical properties, including an optical transmittance of the aromatic polyamide film at 450 nm that was higher than 90%. Additionally, the high quantity of thioether units provided the polymers with high refractive indices of 1.700–1.704 and low birefringences of 0.007–0.008. Copyright © 2012 Society of Chemical Industry

Co-reporter:Zhimei Wei;Quanchao Zhang;Lihua Wang;Minle Peng;Xiaojun Wang;Shengru long
Journal of Polymer Science Part B: Polymer Physics 2012 Volume 50( Issue 20) pp:1414-1420
Publication Date(Web):
DOI:10.1002/polb.23135

Abstract

The focus of this work is the preparation of aramid nanofibers via electrospinning technology and the study of their adsorption properties. In this article, aramid nanofibers were prepared by electrospinning aramid fibers solution with the addition of lithium chloride (LiCl). It showed a good adsorption capacity when methylene blue (MB) was used as the model target. There were much larger adsorption amounts and faster kinetics of uptaking target species of electrospun aramid nanofibers to MB than that of electrospun polyethersulfone (PES) nanofibers. Compared with activated carbon, aramid nanofibers also have a much faster adsorption rate to MB. Aramid nanofibers were subsequently used to effectively remove endocrine disruptors such as bisphenol A (BPA), phenol (Phe), and p-hydroquinone (BPhe) from their aqueous solutions. Additionally, molecule imprinted technology enhances aramid nanofibers with much higher adsorption amounts and special adsorption property for endocrine disruptors. These results showed that aramid nanofibers have the potential to be used in environmental applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

Co-reporter:Quanchao Zhang;Lihua Wang;Zhimei Wei;Xiaojun Wang;Shengru Long
Journal of Polymer Science Part B: Polymer Physics 2012 Volume 50( Issue 14) pp:1004-1012
Publication Date(Web):
DOI:10.1002/polb.23096

Abstract

In this article, a new large-scale aligned fiber mats formation method called salt-induced pulse electrospinning was developed. By electrospinning salted solution in a humid environment, traditional continuous electrospinning changed into pulse electrospinning and aligned fibers were thus formed. The possible mechanisms for the occurrence of salt-induced pulse electrospinning and the formation of fiber alignment were studied. The continuous electrospinning changing into the pulse electrospinning was due to the change of viscosity and conductivity of salted polymer solution in a wet electrospinning condition. Fishing net-shaped whipping region of the electrospinning jet during pulse electrospinning process was considered as the key factor for the formation of fiber alignment. The mechanical properties of the aligned fiber mat increased significantly compared with that of the random fiber mat. This aligned fiber preparation method only requires a very low rotating drum speed as the receiver and can produce large-scale aligned fiber mats for many applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012

Co-reporter:Yan-lun Wang;Gang Zhang;Mei-lin Zhang;Yu Fan
Chinese Journal of Polymer Science 2012 Volume 30( Issue 3) pp:370-377
Publication Date(Web):2012 May
DOI:10.1007/s10118-012-1124-4
Poly(p-arylene sulfide ketone/Schiff base) copolymers (PASK/SB) were prepared by solution polycondensation of 4,4′-diflurobenzophenone (DFBP) and N-phenyl(4,4′-diflurodiphenyl) ketimine (DFBI) with sodium sulfide in the presence of sodium hydroxide under normal pressure. Elemental analyses, FT-IR, NMR, DSC, TGA and XRD were used to characterize the resultant copolymers. It was found that the copolymers had good thermal properties with glass transition temperature (Tg) of 155.0–172.0°C, melting temperature (Tm) of 298–344°C, 5% weight loss temperatures (Td) of 471.0–501.5°C. These copolymers were almost amorphous with the content of DFBI beyond 30%. The polymer with 100% DFBI had excellent solubility, and it could dissolve in some solvents such as tetrahydrofuran (THF) and N-methyl-2-pyrrolidone (NMP). The processability of polymers was improved. Meantime the viscosity of PASK made from hydrolysis of PASK/SB (H-PASK/SB) was greatly improved from 0.135 dL/g to 0.605 dL/g.
Co-reporter:Quanchao Zhang;Lihua Wang;Zhimei Wei;Xiaojun Wang
Colloid and Polymer Science 2012 Volume 290( Issue 13) pp:1257-1263
Publication Date(Web):2012 August
DOI:10.1007/s00396-012-2645-7
A new simple method for the formation of hollow polyethersulfone (PES) microspheres was reported in this paper. Coaxial electrospraying equipment and nonsolvent precipitating bath were used to produce hollow microspheres in one step. The properties of the core solution affected the formation of hollow PES microspheres. To form hollow microspheres in one step, the core solution should be removed directly by a nonsolvent. Additionally, the core solution should also be used to occupy the internal space of microspheres and form a supporting layer at the interface between the core solution and the shell solution. The supporting layer formed by the micro-phase that was caused by the phase separation of the core or shell solution was the key factor for the formation of hollow PES microspheres. The performance of hollow microspheres produced by this method was excellent. This method provided a new simple way to form hollow polymer microspheres and can be extended to other polymers to prepare hollow microspheres in one step.
Co-reporter:Quanchao Zhang;Minxiong Li;Jing Liu;Shengru Long
Colloid and Polymer Science 2012 Volume 290( Issue 9) pp:793-799
Publication Date(Web):2012 June
DOI:10.1007/s00396-011-2563-0
A salt-induced electrospinning method to produce porous polymer ultrafine fibers was reported in this work. Scanning electron microscopy, energy dispersive spectrometer, and BET surface area measurement were employed to evaluate the morphology, the element distribution, and the surface area of fibers, respectively. According to the investigation result, pores on the fiber were induced by water-soluble salt during electrospinning process in a humid spinning environment. There was no porous structure on the fiber surface when water-insoluble salt was used in a wet electrospinning environment or when water-soluble salt was used in a dry electrospinning environment. Compared with pure fibers, the average surface area of fibers containing salt increased significantly due to the porous structure. The possible mechanism of the porous structure induced by salt was proposed. Water-solubility salt and humid environment were considered as the key roles in the formation of porous structure. This method provided a new way to form porous structure during electrospinning.
Co-reporter:Gang Zhang, Guang-Shun Huang, Dong-Sheng Li, Xiao-Jun Wang, Sheng-Ru Long, and Jie Yang
Industrial & Engineering Chemistry Research 2011 Volume 50(Issue 11) pp:7056-7064
Publication Date(Web):April 26, 2011
DOI:10.1021/ie200192v
Semiaromatic polyamides containing thioether units were synthesized through the reaction of 4,4′-thiodibenzoyl chloride (TDC) and diamine by the method of interfacial polycondensation. The inherent viscosities of the resultant polyamides prepared with optimum synthesis conditions were 1.08–1.26 dL/g. These polyamides had excellent thermal properties with glass transition temperatures (Tg) of 119.8–190.1 °C, melting temperatures (Tm) of 281.4–355.5 °C, and initial degradation temperatures (Td) of 433.5–466 °C. They had wider processing windows than traditional semiaromatic polyamides. At the same time, they had better tensile strengths of 62.1–86.5 MPa, better low-temperature mechanical properties, lower water absorption, lower dielectric constants of 3.16–3.81 at 100 kHz, and better melt flowability properties. The results suggest that these semiaromatic polyamides containing thioether units [poly(hexanelene 4,4′-thiodibenzoamide) (PA-6), poly(octanelene 4,4′-thiodibenzoamide) (PA-8), and poly(decanelene 4,4′-thiodibenzoamide) (PA-10)] represent a promising type of heat-resistant and processable engineering plastic.
Co-reporter:Lihua Wang;Quanchao Zhang;Xiaojun Wang;Jing Liu
Journal of Applied Polymer Science 2011 Volume 122( Issue 4) pp:2552-2556
Publication Date(Web):
DOI:10.1002/app.34374

Abstract

This article successfully prepared the red blood cell-shaped microspheres via electrospraying. The polymer solution was comprised of polyether sulfone (PES) and dimethyl sulfoxide (DMSO), and the hydrophilic polyethylene glycol (PEG) was added to regulate and control the structure of the microspheres. When the solution concentration was 7.6 wt % and PES/PEG proportion was 10 : 5 while preparing microspheres, the shape and diameter of the microspheres was the most similar to that of erythrocyte. The results suggested that the forming mechanism of the red blood cell-shaped microspheres be related to two aspects. One is that the microspheres had relatively weak mechanical strength because of the sponge pores internal nanostructure. The other is that the existence of residual solvents and water within the microspheres would dissolve the gel phase PES and then further weaken mechanical strength of the outer layer of the microspheres, which caused the structural changes on the top layer of the spheres, that is, the top layer collapsed, and the microspheres finally turned into the red blood cell-shaped microspheres. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.

Co-reporter:Quanchao Zhang;Yijia Zhang;Qiang Wei;Xiaojun Wang;Jing Liu;Changsheng Zhao
Journal of Applied Polymer Science 2011 Volume 120( Issue 5) pp:2648-2653
Publication Date(Web):
DOI:10.1002/app.33478

Abstract

Polyethersulfone (PES) porous microspheres were prepared via electrospraying technique, and then were used for the removal of endocrine disrupters from aqueous solutions. The surface and the internal structures of electrosprayed microspheres were characterized by scanning electron microscopy (SEM) and the results showed that they were porous. The electrosprayed porous PES microspheres can remove biphenyl A and biphenyl effectively. At the same time, they showed larger adsorption capacity and fast kinetics of uptaking target species than PES injected spheres reported in the earlier publications. The hydrophilicity and porosity of electrosprayed microspheres can be controlled by changing the amount of hydrophilic polyethylene glycol (PEG), which influences the adsorption properties of the microspheres. The results showed that electrosprayed porous PES microspheres have the potential to be used in the environmental application. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Co-reporter:Gang Zhang;Guang-shun Huang;Xiao-jun Wang;Sheng-ru Long
Journal of Polymer Research 2011 Volume 18( Issue 6) pp:1261-1268
Publication Date(Web):2011 November
DOI:10.1007/s10965-010-9528-8
Two kinds of aromatic dibenzoyl chloride monomer containing thioether unit 4,4′-Bis(4-chloroformylphenylthio)benzophenone (BP-DC) and 4,4′-thiodibenzoyl chloride (T-DC) were synthesized with two steps, which was reacted with diamine monomer containing thioether and amide unit to prepare a new kind of polyamide containing high quantity thio-ether group. The intrinsic viscosity of the polyamides was 0.76–0.90 dl/g obtained with optimum synthesis conditions. The polymers were found to have good optical properties: the optical transmittance of the aromatic polyamide film at 450 nm is higher than 80%, meantime the high quantity thio-ether unit provided the polymer with a high refractive index ranging from 1.691 to 1.696 and low birefringence of 0.007–0.008. At the same time the polymers had excellent thermal performance with glass transition temperature (Tg) of 226 °C–278 °C, initial degradation temperature (Td) of 427 °C–439 °C. They showed improved solubility in polar aprotic solvents.
Co-reporter:Gang Zhang, Dong-sheng Li, Guang-shun Huang, Xiao-jun Wang, Sheng-ru Long, Jie Yang
Reactive and Functional Polymers 2011 71(8) pp: 775-781
Publication Date(Web):August 2011
DOI:10.1016/j.reactfunctpolym.2011.04.008
Co-reporter:Yaqi Yang, Gang Zhang, Jing Liu, Shengru Long, Xiaojun Wang, Jie Yang
Polymer 2011 Volume 52(Issue 4) pp:1013-1018
Publication Date(Web):17 February 2011
DOI:10.1016/j.polymer.2011.01.001
Co-reporter:Quanchao Zhang;Jing Liu;Xiaojun Wang;Minxiong Li
Colloid and Polymer Science 2010 Volume 288( Issue 14-15) pp:1385-1391
Publication Date(Web):2010 October
DOI:10.1007/s00396-010-2273-z
The focus of this work is to control and study internal nanostructures of electrosprayed polymer microspheres. In order to make the study easy, the microspheres were cut, and scanning electron microscopy coupled with image analysis software was employed to evaluate the size distributions and the internal nanostructures of microspheres. According to the observation and analysis results, three types of polyethersulfone porous microspheres (perfect sphere-shaped, red blood cell-shaped, and Chinese lantern-shaped) with a diameter ranging from 3 to 20 μm were prepared via electrospraying technology. By controlling the process parameters, the porous microspheres with three kinds of internal nanostructures, namely, macrovoid internal nanostructure, sponge-pore internal nanostructure, and parallel internal macrovoid nanostructure were produced. The results demonstrate that the presence of some additive, such as polyethylene glycol and polyvinyl alcohol, can control the internal nanostructures of the electrosprayed microspheres effectively. The possible mechanism for the formation of internal nanostructures was also proposed.
Co-reporter:Xiao-jun Wang;Mei-lin Zhang;Jing Liu;Gang Zhang
Chinese Journal of Polymer Science 2010 Volume 28( Issue 1) pp:
Publication Date(Web):2010 January
DOI:10.1007/s10118-010-8215-x
The thermal degradation of poly(arylene sulfide sulfone)/N-methylpyrrolidone (PASS/NMP) crystal solvate was studied by thermogravimetric analysis (TGA) and was compared with pure PASS in order to determine the way in which the formation of the crystal solvate affected the thermal properties of the polymer. The activation energy of the solid state process was determined using Kissinger’s method, which does not require knowledge of the reaction mechanism (RM), to be 174.18 kJ/mol which was lower than that for pure PASS (E = 214 kJ/mol). The study of master curves together with interpretation of integral methods, allows confirmation that the thermal degradation mechanism for PASS in the crystal solvate system is a decelerated Rn type, which is a solid-state process based on a phase boundary controlled reaction, in the conversion range considered. Whereas, the pure PASS follows a decelerated Dn thermodegradation mechanism in the same conversion range.
Co-reporter:Chengkun Chen;Chunli Liu;Gang Zhang
Frontiers of Chemistry in China 2009 Volume 4( Issue 1) pp:114-119
Publication Date(Web):2009 March
DOI:10.1007/s11458-009-0015-x
High-molecular-weight polyarylene sulfide sulfone amide (PASSA) and polyarylene sulfide ketone amide (PASKA) were synthesized from diamine monomers containing sulfone or ketone group by a low temperature solution polycondensation reaction in anhydrous N-methylpyrrolidone (NMP). The structures of the monomers and corresponding polymers were identified by IR-spectra and UV spectra. The maximum intrinsic viscosities of the polymers were 0.72 dL/g in NMP (PASSA) and 0.62 dL/g in H2SO4 (PASKA) at 30 ± 0.1°C, respectively. The polymers possess excellent thermal properties with the glass transition temperature (Tg) for PASSA and PASKA are 274.9°C and 195.2°C, respectively. The initial degradation temperatures (Ti) for PASSA and PASKA are 461.55°C and 467.08°C, respectively, which suggests that PASSA and PASKA are excellent heat-resistant materials. The dissolvability experiments show that PASSA and PASKA are also corrosion resistance materials.
Co-reporter:Huadong Wang, Jie Yang, Shengru Long, Xiaojun Wang, Zheng Yang, Guangxian Li
Polymer Degradation and Stability 2004 Volume 83(Issue 2) pp:229-235
Publication Date(Web):February 2004
DOI:10.1016/S0141-3910(03)00266-0
The thermal degradation of poly(phenylene sulfide sulfone) PPSS was studied by thermogravimetric analysis to determine the reaction mechanism. Several tests were carried out at different heating rates. The influence of the heating rate in dynamic measurements (5–40 °C/min) on kinetic parameters, such as activation energies, was also studied. The activation energy of the solid-state process was determined to be 214 kJ/mol using Kissinger's method, which does not require knowledge of the reaction mechanism. The value of the activation energy obtained using Flynn–Wall–Ozawa method was in agreement with that using Kissinger's method. Different reaction mechanisms were used to compare with this value. Also the experimental data were compared to master curves. Analysis of the experimental results suggested that the actual reaction mechanism was a Dn deceleration type.
Poly(1H-benzimidazole-2,5-diylsulfonyl-1H-benzimidazole-5,2-diyl-1,4- phenyleneoxy-1,4-phenylene)
Imperialine
Buflomedil
Benzenethiol, 4,4'-sulfonylbis-
Phenol, chloronitro-
Poly(iminocarbonyl-1,4-phenylenecarbonylimino-1,9-nonanediyl)
Poly(iminocarbonyl-1,4-phenylenecarbonylimino-1,6-hexanediyl)
peimisine
11,14,17-Eicosatrienoicacid, (11Z,14Z,17Z)-