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Synthesis and Characterization of Poly(ether imide)s Containing m-Methyl and Phthalazinone Moieties 被引量:2
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作者 Jin Yan WANG Shu De XIAO Xi Gao JIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第4期331-332,共2页
Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amin... Three novel poly(ether imide)s were synthesized by one-step solution polymerization from 2-(3, 4-dicarboxyl-N-phenyl)-4-(3, 4-dicarboxyl-phenoxyl-4-(2-methyl)-phenyl)-2, 3- phthal-azin-1-one dianhydride and three amines, and characterized. The polymers show good solubility and thermal properties. 展开更多
关键词 synthesis poly(ether imide)s PHTHALAZINONE dianhydride.
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Synthesis and Characterization of Poly (ether imide)s Containing Phthalazinone and Isopropyl Moieties 被引量:1
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作者 Jin Yan WANG Xi Gao JIAN Shu De XIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第7期593-594,共2页
A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-1-one and bisphenol-A diphthalic anhydride was synthesized by one-step ... A novel poly(ether imide)s containing phthalazinone and isopropyl moieties derived from 2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl]-phthalazin-1-one and bisphenol-A diphthalic anhydride was synthesized by one-step solution condensation polymerization in nr-cresol. The polymer was characterized by FTIR, NMR, molecular weights, glass transition temperature, thermal degradation temperature and WAXD. 展开更多
关键词 poly (ether imide) s PHTHALAZINONE one-step solution condensation polymerization
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Synthesis and characterization of new soluble poly(aryl ether nitrile)s containing phthalazinone moiety 被引量:10
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作者 Ming Jing Wang Cheng Liu Li Ming Dong Xi Gao Jian 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第5期595-597,共3页
A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent vis... A series of novel poly(aryl ether nitrile)s containing phthalazinone moiety were synthesized by the nucleophilic displacement reaction of bisphenol-like monomers (I) with 2,6-difluorobenzonitrile. The inherent viscosities ranged from 0.46 to 1.07 dL g^-1. The glass transition temperatures were in the range of 277-295℃, and the temperatures for 10% weight loss in nitrogen atmosphere were found between 495 and 527 ℃. The structures of these resultant polymers were confirmed by FT-IR and 1^H NMR. Moreover, the properties of poly(aryl ether nitrile)s including solubility and crystallinity were also studied. 展开更多
关键词 poly(aryl ether nitrile)s PHTHALAZINONE HEAT-REsIsTANCE solubility
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Synthesis of Novel Poly(aryl ether amide)s Containing the Phthalazinone Moiety 被引量:4
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作者 Lin CHENG~1 Xi Gao JIAN~2 (~1Department of Materials Science & Engineering, Wuhan Institute of Chemical Technology. Wuhan 430074) (Department of Polymer Science & Materials. DaLian University of Technology. DaLian 1 16012) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第4期307-310,共4页
Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one ... Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)phenyl] (2H)phthalazin-1-one and 1,2-dihydro-2-(4-aminophenyl)-4-[4-(4-aminophenoxy)-3,5-dimethylphenyl](2H)phthalazin-1-one were successfully synthesized from readily available heterocyclic bisphenol-like monomers in two steps in high yield. A series of novel poly(aryl ether amide)s containing the phthalazinone moiety were successfully prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. 展开更多
关键词 poly(aryl ether amide)s PHTHALAZINONE direct polymerization heterocyclic diamine
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SYNTHESIS AND PROPERTIES OF SULFONATED POLY(ARYLENE ETHER) CONTAINING TRIPHENYL METHANE MOIETIES FROM ISOCYNATE MASKED BISPHENOL 被引量:2
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作者 王雷 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第4期419-426,共8页
A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place ... A novel sulfonated poly(arylene ether) containing triphenylmethane moieties was synthesized by the sulfonation of a designed parent polymer using chlorosulfonic acid as sulfonation agent. The sulfonation took place at the para position of the pendant phenyl rings because of the specially designed parent polymer. The position and degree of sulfonation were characterized by ^1H-NMR and elemental analysis. The sulfonated polymers are highly soluble in common organic solvents, such as dimethylsulfoxide, N,N'-dimethylacetamide, dimethylformamide, ethylene glycol monomethyl ether, and can be readily cast into tough and smooth films from solutions. The films showed good thermal and hydrolysis stabilities. Moreover, Fenton's reagent test revealed that the films exhibited superior stability to oxidation. The proton conductivities of the films were comparable with Nation 117 under same conditions. The membrane electrode assembly (MEA) prepared with the asmade film (706 EW, 100 μm dry thickness) shows better cell performance than Nation 115-MEA in the whole current density range. 展开更多
关键词 sulfonated poly(arylene ethers Proton-exchange membrane Conductivity.
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SYNTHESIS OF NEW AROMATIC POLY(AMIDE IMIDE)S FROM UNSYMMETRICAL EXTENDED DIAMINE CONTAINING A PHTHALAZINONE MOIETY 被引量:1
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作者 程琳 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2004年第4期389-393,共5页
The direct polymerization of an unsymmetrical kink non-coplanar heterocyclic diamine (1) with various aromatic bis(trimellitimide)s (2a-e) using triphenyl phosphite and pyridine as condensing agents could generate a s... The direct polymerization of an unsymmetrical kink non-coplanar heterocyclic diamine (1) with various aromatic bis(trimellitimide)s (2a-e) using triphenyl phosphite and pyridine as condensing agents could generate a series of new aromatic poly(amide imide)s (3a-e) containing the kink non-coplanar phthalazinone heterocyclic units in the polymer main chains with inherent viscosities of 0.58-0.66 dL/g. The polymers are readily soluble in a variety of solvents such as N,N- dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidinone, pyridine and m-cresol and can be cast to form flexible and tough films. The glass transition temperatures of polymers (Tg) are in the range of 301-327°C, and the temperatures for 5% weight loss in nitrogen are in the range of 498-521 'C. 展开更多
关键词 poly(arylene amide imide)s Heterocyclic polymer High-performance polymer PHTHALAZINONE
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Synthesis and properties of soluble poly(aryl ether sulfone ether ketone)s copolymers containing pendant methyl groups 被引量:1
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作者 ZHONG Ming YU Wen-wen SONG Cheng LIU Yong-jun SONG Cai-sheng 《Journal of Chemistry and Chemical Engineering》 2009年第4期26-31,38,共7页
A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy d... A series of Poly(arly ether sulfone ether ketone)s containing pendant methyl groups were synthesized by the reaction of 4,4'-[sulfonylbis (1,4-phenylene)dioxy] dibenzoyl chloride (SODBC) with 4,4'- diphenoxy diphenylsulfone (DPODPS), 4,4'- di(2-methylphenoxy) diphenylsulfone (o-Me-DPODPS), 4,4'- di(3-methylphenoxy) diphenylsulfone (m-Me-DPODPS), 4,4'- di (2,6-bimethylphenoxy) biphenylsulfone(o-Me2-DPODPS) respectively, in a mixture of 1,2-dichloroethane (DCE) and N-methylpyrrolidone (NMP). These reactions were catalyzed by anhydrous aluminum chloride (AlCl). The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature (Tg) in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly(aryl ether sulfone ketone)s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones. 展开更多
关键词 poly (aryl ether sulfone ether ketone)s characterization sOLUBLE pendent methyl groups
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Liquid Crystalline Polymers XIII Main Chain Thermotropic Copoly (Arylidene-Ether)s Containing 4-Teriary Butyl-Cyclohexanone Moiety Linked with Polymethylene Spacers 被引量:2
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作者 Nayef S. Al-Muaikel Kamal I. Aly 《Open Journal of Organic Polymer Materials》 2013年第1期19-26,共8页
A new homologous series of thermotropic liquid crystalline copoly(arylidene-ether)s based on 4-teriary butyl cyclohexanone moiety were synthesized by solution polycondensation of 4,4’-diformyl-α,ω-diphenoxyalkanes,... A new homologous series of thermotropic liquid crystalline copoly(arylidene-ether)s based on 4-teriary butyl cyclohexanone moiety were synthesized by solution polycondensation of 4,4’-diformyl-α,ω-diphenoxyalkanes, Ia-d or 4,4’- diformyl-2,2’-dimethoxy-α,ω-diphenoxyalkanes IIa-d with the 4-teriary butyl-cyclohexanone III and cyclopentanone. A model compound IV was synthesized from the monomer III with benzaldehyde and characterized by elemental and spectral analyses. The inherent viscosities of the resulting polymers were in the range 0.22 - 0.92 dI/g. All the copoly(arylidene-ether)s were insoluble in common organic solvents but dissolved completely in concentrated H2SO4 and formic acid. The mesomorphic properties of these polymers were studied as a function of the diphenoxyalkane space length. Their thermotropic liquid crystalline properties were examined by DSC and optical polarizing microscopy and demonstrated that the resulting polymers form nematic mesophases over wide temperature ranges. The thermogravimetric analyses of those polymers were evaluated by TGA and DSC measurements and correlated to their structural units. X-Ray analysis showed that copolymers having some degree of crystallinity in the region 2q = 5° -60°. In addition, the morphological properties of selected examples were tested by Scanning electron microscopy. 展开更多
关键词 Liquid Crystal THERMOTROPIC synthesis Characterization poly(Arylidene-ether)s
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Synthesis and Characterization of Poly(ether amide)s Containing Bisphthalazinone and Ether Linkages
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作者 ChengLIU ShouHaiZHANG MingJingWANG QiZhenLIANG XiGaoJIAN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第4期437-439,共3页
A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitril... A novel aromatic diacid, 4, 4'-bis[2-(4-carboxyphenyl)phthalazin-1-one-4-yl]-bisphenyl ether III, containing bisphthalazinone and ether linkages was prepared from nucleophilic substitution of p-chlorobenzonitrile with the bisphenol-like monomer I, followed by alkaline hydrolysis of the intermediate dinitrile II. A series of poly(ether amide)s containing bisphthala- zinone and ether linkages derived from diacid III and aromatic diamines were synthesized by one-step solution condensation polymerization using triphenyl phosphite and pyridine as condensing agents. Moreover, the properties of poly(ether amide)s including thermal stability, solubility and crystallinity were also studied. 展开更多
关键词 poly(ether amide) s bisphthalazinone thermal stability solubility.
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Synthesis and characterization of novel poly(aryl ether)s containing naphthyl moieties
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作者 Lei Wang Guang Ming Zhu 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第8期965-968,共4页
Two poly(aryl ether)s containing naphthyl moieties were prepared from bis(3,5-dimethyl-4-hydroxyphenyl)naphthyl methane (monomer 1) via nucleophilic aromatic substitution polycondensation with bis(4-fluoropheny... Two poly(aryl ether)s containing naphthyl moieties were prepared from bis(3,5-dimethyl-4-hydroxyphenyl)naphthyl methane (monomer 1) via nucleophilic aromatic substitution polycondensation with bis(4-fluorophenyl) ketone and bis(4-fluorophenyl) sulfone. The structures of these polymers were confirmed by 1H NMR. The Mn values of the two polymers were 96,200 and 88,600, respectively. The polymers exhibited good thermal stabilities with 5% mass loss at T 〉 400 and high glass-transition temperature (Ts) of T 〉 250 ℃. Moreover, the resultant polymers were amorphous determined by wide angle X-ray diffraction (WAXD). ?2009 Lei Wang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All fights reserved. 展开更多
关键词 poly(aryl ethers Naphthyl moieties Thermal properties Chemical synthesis
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SYNTHESIS AND CRYSTALLIZATION BEHAVIOR OF POLY(ETHER ETHER KETONE ETHER KETONE)(PEEKEK)
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作者 Zhao-bin Qiu Zhi-shen Mo +2 位作者 Ying-ning Yu Hong-fang Zhang Xian-hong Wang Polymer Physics Laboratory, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第2期129-132,共4页
In this paper, the synthesis and crystallization behavior of poly(ether ether ketone ether ketone) (PEEKEK) are reported. PEEKEK was prepared from 4,4'-bis(p-fluorobenzoyl) diphenyl ether (4,4'-FBDE) and hydro... In this paper, the synthesis and crystallization behavior of poly(ether ether ketone ether ketone) (PEEKEK) are reported. PEEKEK was prepared from 4,4'-bis(p-fluorobenzoyl) diphenyl ether (4,4'-FBDE) and hydroquinone along the nucleophilic substitution route. The thermal properties were investigated by using DSC and TGA. The crystallization behavior of PEEKEK under several conditions, i.e., crystallization from the molten state (melt crystallization), crystallization from a quenched sample (cold crystallization) and crystallization induced by exposing glassy sample to methylene chloride (solvent-induced crystallization) has also been investigated. The results show that crystallization of PEEKEK could be induced by the above methods, and no polymorphism was found. The differences in the crystallization of PEEKEK induced by the above methods are seen in their degree of crystallinity. 展开更多
关键词 poly(aryl ether ketone)s sYNTHEsIs CRYsTALLIZATION
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Synthesis of Poly(aryl amide imide)s Derived from o-diphenyltrimellitic Anhydride
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作者 程琳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2002年第3期90-93,共4页
The synthesis and characterization of a series of novel poly(aryl amide imide)s based on o diphenyltrimellitic anhydride are described.The poly(aryl amide imide)s having inherent viscosities of 0.39-1.43dL/g in N m... The synthesis and characterization of a series of novel poly(aryl amide imide)s based on o diphenyltrimellitic anhydride are described.The poly(aryl amide imide)s having inherent viscosities of 0.39-1.43dL/g in N methyl 2 pyrrolidinone at 30℃,were prepared by polymerization with aromatic diamines in N,N-dimethylacetamide and subsequent chemical imidization.All the polymers were amorphous,readily soluble in aprotic polar solvents such as DMAC,NMP,DMF,DMSO,and m cresol,and could be cast to form flexible and tough films.The glass trsanition temperatures were in the range of 284-336℃,and the temperatures for 5% weight loss in nitrogen were above 468℃. 展开更多
关键词 poly (aryl amide imide) s o-diphenyltrimellitic acid synthesis
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SYNTHESIS AND CHARACTERIZATION OF POLY(PHTHALAZINONE ETHER PHOSPHINE OXIDE)S BY N-C COUPLING REACTION
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作者 程琳 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第2期287-290,共4页
Based on several unsymmetrical, twist, noncoplanar phthalazinone-containing monomers 2a-2e and an active bis(4-fluorophenyl)phenyl phosphine oxide (BFPPO) monomer, a series of novel poly(phthalazinone ether phosp... Based on several unsymmetrical, twist, noncoplanar phthalazinone-containing monomers 2a-2e and an active bis(4-fluorophenyl)phenyl phosphine oxide (BFPPO) monomer, a series of novel poly(phthalazinone ether phosphine oxide)s (PPEPO) was synthesized by anhydrous K2CO3 mediated N-C coupling reaction in DMAc. The polymers exhibited good thermal properties with Tgs ranging from 267℃ to 306℃ and 5% weight loss temperatures in nitrogen higher than 430℃, together with high char yield upon prolonged heating at 800℃ (35%-56%). Moreover, the polymers were readily soluble in common organic solvents, such as N-methyl-2-pyrrolidone, chloroform and m-cresol. These polymers had inherent viscosities in the range of 0.45-0.72 dL/g and could be cast into flexible and colorless films by spin coating or casting approach. 展开更多
关键词 PHTHALAZINONE poly(phthalazinone ether phosphine oxide)s synthesis.
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Synthesis and characterization functionalized poly(ether ether ketone)s with carboxylic groups
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作者 王冬 高鸿 姜振华 《Journal of Beijing Institute of Technology》 EI CAS 2012年第1期118-121,共4页
A novel type of aromatic poly( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl)pentanoic acid with difluoro-monomers. Their mo- lecular structures were deter... A novel type of aromatic poly( ether ether ketone) s with carboxyl groups were prepared by polycondensation of 4,4-bis(4-hydroxyphenyl)pentanoic acid with difluoro-monomers. Their mo- lecular structures were determined by ^1H-NMR and IR, respectively. Their molecular weights were measured by gel permeation chromatography ( GPC ), which showed that all the polymers had high molecule weights ( 〉 42 000). Due to the long side chains of polymers, all the polymers had good solubility (soluble in NMP, DMAc, THF, etc. ). The differential scanning calorimeter (DSC) detected their excellent glass transition temperatures ( Tg ) up to 195 ℃. The Tg increased with the content of carboxylic units in the polymer chains, because the interactions of H bonds increased with increasing content of carboxylic. The polymers could form transparent and flexible films, which make them a candidate for membrane materials. 展开更多
关键词 poly ether ether ketone) s carboxylic groups high Tg
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New optically active poly(amide-imide)s derived from N,N'-(4,4-diphthaloyl)-bis-L-leucine and hydantoin derivatives:Synthesis and properties
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作者 Khalil Faghihi 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第10期1153-1156,共4页
Six new optically active poly(amide-imide)s (5a-f) were synthesized through the direct polycondensation reaction of N,N′-(4,4′- diphthaloyl)-bis-L-leucine (3) with six hydantoin derivatives (4a-f). Tripben... Six new optically active poly(amide-imide)s (5a-f) were synthesized through the direct polycondensation reaction of N,N′-(4,4′- diphthaloyl)-bis-L-leucine (3) with six hydantoin derivatives (4a-f). Tripbenyl phosphite (TPP)/pyridine in the presence of calcium chloride (CaCl2) and N-methyl-2-pyrrolidone (NMP) were successfully applied for direct polycondensation. The polycondensation reactions produce a series of new poly(amide-imide)s (5a-f) in high yields, and inherent viscosity between 0.42 and 0,55 dL/g. The resulting poly(amide-imide)s (5a-f) were characterized by elemental analysis, viscosity measurements, thermal gravimetric analysis (TGA and DTG), solubility test and FT-IR spectroscopy. 展开更多
关键词 High performance polymers poly(amide-imides Direct polycondensation Hydantoin derivatives
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Organosoluble and Thermally Stable of Benzazole-Containing Poly(Imide-Urea)s: One-Pot Synthesis and Characterization
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作者 Hojjat Toiserkani 《Open Journal of Polymer Chemistry》 2011年第1期1-9,共9页
The preparation of new types of poly(imide-urea)s (PIUs) with high thermal stability and improved solubility was investigated. Three series of aromatic poly(imide-urea)s (PIUOa-c, PIUSa-c, and PIUNa-c) bearing pendent... The preparation of new types of poly(imide-urea)s (PIUs) with high thermal stability and improved solubility was investigated. Three series of aromatic poly(imide-urea)s (PIUOa-c, PIUSa-c, and PIUNa-c) bearing pendent benzoxazole, benzothiazole or benzimidazole rings were prepared by one-pot polycondensation reaction of three bis(imide-carboxylic acid)s, 2-[3,5-bis(N-trimellitimidoyl)-phenyl]benzoxazole (1O), 2-[3,5-bis(N- trimellitimidoyl)-phenyl]benzothiazole (1S), or 2-[3,5-bis(N-trimellitimidoyl)-phenyl]benzimidazole (1N) with various kinds of aromatic diamines (a-c). The effects of the benzazole pendent groups on the polymer properties such as solubility and thermal stability were investigated by comparison of the polymers. All of the resulting polymers exhibited excellent solubility in common polar solvents. The glass transition temperature of the polymers determined by DSC thermograms were in the range 192℃ - 236℃. The temperatures at 10% weight loss from their TGA curves were found to be in the range 390℃ - 441℃ in nitrogen. 展开更多
关键词 poly(imide-Urea)s sTRUCTURE-PROPERTY Relation Thermal Properties Benzazole PENDENT Groups
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Highly stable side-chain-type cardo poly(aryl ether ketone)s membranes for vanadium flow battery 被引量:1
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作者 Ziming Zhao Qing Dai +6 位作者 Sihan Huang Wenjing Lu Yaohan Chen Jifu Zheng Suobo Zhang Shenghai Li Xianfeng Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第3期167-170,共4页
Vanadium flow batteries(VFBs)have drawn considerable attention as an emerging technology for largescale energy storage systems(ESSs).One of the pivotal challenges is the availability of eligible ion exchange membranes... Vanadium flow batteries(VFBs)have drawn considerable attention as an emerging technology for largescale energy storage systems(ESSs).One of the pivotal challenges is the availability of eligible ion exchange membranes(ICMs)that provide high ion selectivity,proton conductivity,and stability under rigorous condition.Herein,a‘side-chain-type’strategy has been employed to fabricate highly stable phenolphthalein-based cardo poly(arylene ether ketone)s(PAEKs)membrane with low area resistance(0.058Ωcm^(2)),in which flexible alkyl spacers effectively alleviated inductive withdrawing effect from terminal ion exchange groups thus enabling a stable backbone.The assembled VFBs based on PAEKs bearing pendent alkyl chain terminated with quaternary ammonium(Q-PPhEK)demonstrated an energy efficiency above 80%over 700 cycles at 160 mA/cm^(2).Such a remarkable results revealed that the side-chain-type strategy contributed to enhancing the ICMs stability in strong oxidizing environment,meanwhile,more interesting backbones would be woken with this design engaging in stable ICMs for VFBs. 展开更多
关键词 Vanadium flow battery Energy storage technology Ion exchange membrane Ion transport mechanism poly(arylene ether ketone)s(PAEKs)
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Molecular Chain Flexibility and Dielectric Loss at High-Frequency:Impact of Ester Bond Arrangement in Poly(ester imide)s
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作者 Ya-Dong Li Hong Li +6 位作者 Lu-Kun Feng Feng Bao Ming-Liang Wang Cai-Zhen Zhu Zhao-Hui Zheng Xiao-Bin Ding Jian Xu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第8期1122-1133,共12页
The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer media.Traditionally,it has been theorized that rigid molecular chains lead to lower dielec... The evolution of high-frequency communication has accentuated the significance of controlling dielectric properties in polymer media.Traditionally,it has been theorized that rigid molecular chains lead to lower dielectric loss.However,the validity of this proposition at high frequencies remains uncertain.To scrutinize the correlation between chain flexibility and dielectric properties,we synthesized six poly(ester imide)s(PEIs)with systematically varied molecular chain flexibilities by modifying the ester's substitution on the aromatic ring.The introduction of ester bonds bestowed all PEI films with a low dielectric dissipation factor(D_(f)),ranging from 0.0021 to 0.0038 at 10 GHz in dry conditions.The dry D_(f)displayed a pattern consistent with volume polarizability(P/V).Unexpectedly,PI-mmm-T,featu ring the most flexible molecular chain,exhibited the lowest dielectric loss under both dry(0.0021@10 GHz)and hygroscopic(0.0029@10 GHz)conditions.Furthermore,the observed increase in D_(f)after humidity absorption suggests that the high dielectric loss of PEI in applications may be attributed to its hygroscopic nature.Molecular simulations and characterization of the aggregation structure revealed that the smaller cavities within flexible molecular chains,after close stacking,impede the entry of water molecules.Despite sacrificing high-temperature resistance,the precursor exhibited enhanced solubility properties and could be processed into high-quality films.Our research unveils new insights into the relationship between flexibility and highfrequency dielectric loss,offering innovative perspectives on synthesizing aromatic polymers with exceptional dielectric properties. 展开更多
关键词 5G communications poly(ester imide)s Molecular chain flexibility Dielectric properties Humidity absorption
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SYNTHESIS AND CHARACTERIZATIONS OF NEAR INFRARED ABSORBING POLYMERS 被引量:1
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作者 Ying-huaQi PierreDesjardins +3 位作者 MariaBirau Xian-guoWu Zhi-yuanWang Zhi-yuanWang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第2期147-152,共6页
A series of near infrared (NIR) absorbing dinuclear ruthenium dicarbonylhydrazine complexes (DCH-Ru),[{Ru(bpy)_2)_2μ-DCH]^(n+) (where bpy = 2,2'-bipyridinc and n = 2, 3 or 4), were prepared. The DCH-Ru complexes ... A series of near infrared (NIR) absorbing dinuclear ruthenium dicarbonylhydrazine complexes (DCH-Ru),[{Ru(bpy)_2)_2μ-DCH]^(n+) (where bpy = 2,2'-bipyridinc and n = 2, 3 or 4), were prepared. The DCH-Ru complexes areelectrochromic in the NIR region with a high absorption coefficient at 1550-1600 nm typically over 10000 M^(-1)cm^(-1). DCH-Ru complex polymers with good NIR electrochromic properties were also obtained and processed to make a device foroptical attenuation at a wavelength of 1550 nm. The potential of these DCH-Ru polymers for use in a variable opticalattenuator has been demonstrated with an attenuating power at the 1550-nm telecommunication wavelength over 7.0 dB permicron of polymer film thickness. Other classes of NIR active materials are the pentacenediquinones and the correspondingpoly(ether pentacenediquinone)s. These polymers can be electrochemically reduced to the corresponding semiquinone(radical anion) having NIR absorption within a telecom window (e. g., 1310 nm). 展开更多
关键词 Near infrared absorption Dinuclear ruthenium complex poly(ether pentacenediquinone)s Radical anion Optical attenuation
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Composition Dependence of the Thermal Behavior,Morphology and Properties of Biodegradable PBS/PTMO Segment Block Copolymer 被引量:6
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作者 黄勇 LIU Junhong +1 位作者 周涛 张爱民 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第1期219-226,共8页
A series of aliphatic biodegradable poly(ether-ester)s based on poly(butylene succinate)(PBS)as hard segment and poly(tetramethylene oxide)(PTMO,M_n=1 000 g/mol) as soft segment were synthesized.The composit... A series of aliphatic biodegradable poly(ether-ester)s based on poly(butylene succinate)(PBS)as hard segment and poly(tetramethylene oxide)(PTMO,M_n=1 000 g/mol) as soft segment were synthesized.The composition dependence of thermal behavior,morphology and mechanical properties was investigated by differential scanning calorimetry(DSC),atomic force microscopy(AFM),and tensile testing.The crystallization temperature(T_c) and melting temperature(T_m) of the PBS block within poly(ether-ester)s decrease steadily at first,but decrease sharply with PTMO content above 50 wt%.Two crystallization peaks were detected for PTMO in PBSPTMO60 sample,suggesting the occurrence of fractionated crystallization.The crystallization enthalpies(△H_c) and melting enthalpies(△H_m) of PBS block decrease at first,then increase as PTMO content increases further.AFM has demonstrated that phase-separated morphology transforms from a phase of continuous hard matrix to one of continuous soft matrix containing isolated hard domain as PTMO content is increased.Finally,the results of tensile testing show that the poly(ether-ester)s present the behavior of plastics when PTMO content is below 40 wt%,and of thermoplastic elastomers with PTMO content above 50 wt%.By varying the composition of copolymer,the aliphatic poly(ether-ester)s plastics,or especially biodegradable aliphatic poly(ether-ester)s thermoplastic elastomers can be obtained. 展开更多
关键词 polyether-ester)s poly(butylene succinate) poly(tetramethylene oxide) thermoplastic elastomers biodegradable polymer
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