期刊文献+
共找到44篇文章
< 1 2 3 >
每页显示 20 50 100
EFFECT OF CHEMICAL STRUCTURE OF COMONOMERS ON THE PROPERTIES OF COPOLYESTERS 被引量:7
1
作者 武荣瑞 高谨 李慧萍 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第3期226-230,共5页
The effect of different kinds of comonomers with or without flexible chain on properties of copolyesters, such as transition temperature, crystallization velocity, crystallinity and size Of crystallites, is studied. T... The effect of different kinds of comonomers with or without flexible chain on properties of copolyesters, such as transition temperature, crystallization velocity, crystallinity and size Of crystallites, is studied. The experimental results indicate the obvious difference in properties between comonomers with iso-and ortho-structure of phenyl ring and comonomers with flexible chain. The influence of chemical structure of comonomers on properties of copolyesters is discussed. 展开更多
关键词 copolyesters POLYETHYLENETEREPHTHALATE COMONOMER chemical structure
下载PDF
Preparation and characterization of biodegradable aliphatic-aromatic copolyesters/nano-SiO_2 hybrids via in situ melt polycondensation 被引量:2
2
作者 Yan Zhang Bing Tao Wang +2 位作者 Zheng Hong Guo Jie Chen Zheng Ping Fang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第11期1348-1352,共5页
In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO2 hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO)... In situ melt polycondensation was proposed to prepare biodegradable aliphatic-aromatic copolyesters/nano-SiO2 hybrids based on terephthalic acid (TPA), poly(L-lactic acid) oligomer (OLLA), 1,4-butanediol (BDO) and nano-SiO2. TEM and FT-IR characterizations confirmed that TPA, OLLA and BDO copolymerized to obtain biodegradable copolyesters, poly(butylene terepbthalate-co-lactate) (PBTL), and the abundant hydroxyl groups on the surface of nano-SiO2 provided potential sites for in situ grafting with the simultaneous resulted PBTL. The nano-SiO2 particles were chemically wrapped with PBTL to form PBTL/nano- SiO2 hybrids. Due to the good dispersion and interfacial adhesion of nano-SiO2 particles with the copolyester matrix, the tensile strength and the Young's modulus increased from 5.4 and 5.6 MPa for neat PBTL to 16 and 390 MPa for PBTL/nano-SiO2 hybrids with 5 wt.% nano-SiO2, respectively. The mechanical properties of PBTL/nano-SiO2 hybrids were substantially improved. 展开更多
关键词 Biodegradable aliphatic-aromatic copolyesters PBTL/nano-SiO2 hybrids In situ melt polycondensation
下载PDF
Synthesis and Structure of Butylene Terephthalate-ε-Caprolactone Copolyesters 被引量:1
3
作者 Xiao Min CHENG Xiao Lie LUO +1 位作者 Zhi Bo LI De Zhu MA(Department of Polymer Science and Engineering. University of Science and Technology of China.Hefei. Anhui 230026) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第7期593-596,共4页
A series of butylene terephthalate-E-caprolactone copolyesters (BCL) with different hard segment content were successfully synthesized and characterized by 1H-NMR. DSC. PLM and U viscometer, The sequence structure and... A series of butylene terephthalate-E-caprolactone copolyesters (BCL) with different hard segment content were successfully synthesized and characterized by 1H-NMR. DSC. PLM and U viscometer, The sequence structure and crystallization characteristics of BCL copolyesters were carefully investigated. 展开更多
关键词 BCL copolyesters POLYCONDENSATION hard segment soft segment sequence structure crystallization behavior spherulite morphology
下载PDF
Research in the Degradation and Antifouling Performance of Copolyesters of L-Lactide and ε-Caprolactonen 被引量:1
4
作者 WANG Jing-jing LIU Chao +3 位作者 HUANG Cong-shu JIANG Xue-zhi XIE Zhi-peng YE Zhang-ji 《腐蚀与防护》 北大核心 2012年第S1期49-54,共6页
Block copolyesters of L-lactide and ε-caprolactone were synthesized by melt copolymerization of ε-caprolactone and L-lactide.The degradation performance of copolyesters was investigated by quartz crystal microbalanc... Block copolyesters of L-lactide and ε-caprolactone were synthesized by melt copolymerization of ε-caprolactone and L-lactide.The degradation performance of copolyesters was investigated by quartz crystal microbalance with dissipation(QCM-D).Diisocyanate terminated copolyesters could obtain via the reaction of copolyesters and diisocyanate.Diisocyanate terminated copolyesters could react with polyol resin to prepare degradable polyurethane which can be used in antifouling coatings.In this paper,we also discussed the degradation products release action and antifouling performance of the copolyesters film. 展开更多
关键词 L-LACTIDE Ε-CAPROLACTONE copolyesters DEGRADATION
下载PDF
SYNTHESIS AND PROPERTIES OF THERMOTROPIC LIQUID CRYSTALLINE COPOLYESTERS CONTAINING BIS(4-HYDROXYPHENYL)METHANONE(Ⅴ)
5
作者 De Wen DONG Yu Shan NI (Changchun Institute of Applied Chemistry, Academia Sinica, Changchun,130022) 《Chinese Chemical Letters》 SCIE CAS CSCD 1995年第11期951-954,共4页
A new series of fully aromatic thermotropic liquid crystalline copolyesters were synthesized by thermal polycondensation of p-hydroxybenzoic acid [PHB], terephthalic acid [TPA], resorcinol [RES] and bis (4-hydroxyphen... A new series of fully aromatic thermotropic liquid crystalline copolyesters were synthesized by thermal polycondensation of p-hydroxybenzoic acid [PHB], terephthalic acid [TPA], resorcinol [RES] and bis (4-hydroxyphenyl) methanone [BHP]. The DSC traces of copolyesters exhibited two or three endotherms, the low temperature endotherm(Tm) of which indicated the transition from solid state to anisotropic phase. Observation under polarizing microscope and WAXD measurements suggested that the LC-phase formed immediately above Tm had a nematic character. 展开更多
关键词 BIS HYDROXYPHENYL copolyesters METHANONE CONTAINING AND
下载PDF
SYNTHESIS OF LIQUID CRYSTALLINE COPOLYESTERS WITH T-SHAPED TWO-DIMENSIONAL MESOGENIC UNIT AND CROWN ETHER CYCLE
6
作者 张晓静 李自法 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期171-176,共6页
A novel series of liquid crystalline copolyesters with T-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4′-bis(4-hydroxyphenylazo)dibenzo-18-crown-6 was prepared via solution condensation polyme... A novel series of liquid crystalline copolyesters with T-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4′-bis(4-hydroxyphenylazo)dibenzo-18-crown-6 was prepared via solution condensation polymerization from 4,4′-(α,ω-hexanedioyloxy)dibenzoyl dichloride(M_1),2-(4′-ethoxyphenyl)hydroquinone(M_2)and cis-4,4′-bis(4- hydroxyphenylazo)dibenzo-18-crown-6(M_3).The molecular weights of copolyesters are not high,and the intrinsic viscosity [η]of copolyesters ranges from 0.29-0.43.The monomers ... 展开更多
关键词 T-shaped two-dimensional mesogenic unit Crown ether Liquid Crystalline copolyesters Synthesis.
下载PDF
SYNTHESIS OF MAIN CHAIN LIQUID CRYSTALLINE COPOLYESTERS WITH X-SHAPED TWO-DIMENSIONAL MESOGENIC UNIT AND CROWN ETHER CYCLE
7
作者 Jing-wu Wang Shi-jun Zheng +5 位作者 Xiao-hui Xu Xing-qi Zhu Shu-yuan Zhang Tie-sheng Li Zi-fa Li Qi-feng Zhou 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2005年第5期549-556,共8页
A novel series of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4'-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 was prepared via solution conde... A novel series of main chain liquid crystalline copolyesters with X-shaped two-dimensional mesogenic unit and crown ether cycle of cis-4,4'-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 was prepared via solution condensation polymerization from 4,4'-(a;arhexanedioyloxy) dibenzoyl dichloride (MI), 2,5-bis(p-octyloxybenzoyloxy) hydro-quinone (M2) and cis-4,4'-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 (M3). Monomer MI was synthesized by esterification and substitution of adipoyl chloride with p-hydroxybenzoic acid, monomer M2 was synthesized by esterfication and reduction reaction of 2,5-dihydroxybenzoquinone and p-octanoxybenzoyl chloride and monomer M3 was synthesized by diazotization and coupling reaction of cis-diaminodibenzo-18-crown-6 with phenol. The molecular weights of copolyesters are not high, and the intrinsic viscosity [η] of copolyesters ranges from 0.25-0.35. The monomers' structures were identified by using elemental analysis, IR, UV, ^1H-NMR, MS, etc. All the copolyesters are yellowish powders and insoluble in THF and CHC13 at room temperature except cPg. The properties of copolyesters were investigated by using GPC, [η] , DSC, TG, WAXD and POM. It was found that all the copolyesters entered into liquid crystal phase when they were heated to above their melting temperature (Tin). The typical smectic and nematic phase texture can be observed on POM. Their mesophase transition temperature and thermal stability change regularly with varying the content of cis-4,4'-bis(4-hydroxyphenylazo) dibenzo-18-crown-6 unit in the copolyesters. 展开更多
关键词 X-shaped two-dimensional mesogenic unit Crown ether Liquid crystalline copolyesters Synthesis.
下载PDF
PREPARATION OF LIQUID CRYSTALLINE COPOLYESTERS WITH SPACERS BASED ON BISPHENOL-A,BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION
8
作者 汪平平 张鸿志 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1989年第1期9-15,共7页
Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild con... Four series of copolyesters were synthesized by direct polycondonsation reaction between aromatic dicarboxylic acids and bisphenols by using tosyi chloride and N, N-dimethylformamide ( DMF ) in pyridine under mild conditions. The electron-rich hydroxyl groups of bisphenols favoured the polycondensation reaction and the order of relative reactivities of bisphenols is as follow:bisphenoI-A> hydroquinone ~ bisphenol-S> chlorohydroquinone. The mesomorphic properties of copolyesters were examined by birefringence under polarizing microscope, melt transparency. DSC and X-ray diffraction. The minimum molar fraction of mesogenic units needed for the appearance of liquid crystallinity is not higher than 0. 1 despite of the different varieties and lengths of the spacers studied. 展开更多
关键词 TPA PREPARATION OF LIQUID CRYSTALLINE copolyesters WITH SPACERS BASED ON BISPHENOL-A BISPHENOL-S OR POLYSULFONE BY DIRECT POLYCONDENSATION BPA BPS IPA
下载PDF
Biobased Vanillic Acid and Ricinoleic Acid: Building Blocks for Fully Renewable Copolyesters
9
作者 Claudio Gioia Maria Barbara Banella +5 位作者 Grazia Totaro Micaela Vannini Paola Marchese Martino Colonna Laura Sisti Annamaria Celli 《Journal of Renewable Materials》 SCIE 2018年第1期126-135,共10页
New fully biobased polyether/esters have been synthesized by a one-pot polymerization reaction of ricinoleic acid(RA),vanillic acid(VA)and ethylene carbonate(EC).In particular,EC selectively reacts with the phenolic g... New fully biobased polyether/esters have been synthesized by a one-pot polymerization reaction of ricinoleic acid(RA),vanillic acid(VA)and ethylene carbonate(EC).In particular,EC selectively reacts with the phenolic group of VA to obtain in-situ 4-(2-hydroxyethoxy)-3-methoxybenzoate(EV),suitable for subsequent copolymerization with RA.The procedure was carried out in a single step,without any solvent.Chemical structure and thermal properties of the new materials were studied in order to explore relationships between composition and final performances.The combination of EV,bearing a rigid aromatic structure,with RA,characterized by high flexibility and potential biocidal activity,allows the production of a novel class of fully biobased aliphatic-aromatic polymers presenting tuneable thermal properties and suitable for a range of applications,for example,in active packaging and biomedical fields. 展开更多
关键词 Biobased building blocks vanillic acid ricinoleic acid copolyesters
下载PDF
SYNTHESIS OF DIACETYLENE-CONTAINING COPOLYESTERS AND THEIR DFFECT ON ELECTRO-OPTICAL PROPERTIES OF LIQUID CRYSTALS
10
作者 Xiao-fang Chen Yao-wen Bai +4 位作者 Yu-guo Ma Chen-hui Wang Dong Zhang Xin-hua Wan Qi-feng Zhou Department of Polymer Science and Engineering, College of Chemistry, Peking University, Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第2期193-196,共4页
Some diacetylene-containing copolyesters with different ratios of dipropargyl 1,10-decanate anddipropargyl terephthalate were synthesized. Properties of these copolymers were characterized by differentialscanning calo... Some diacetylene-containing copolyesters with different ratios of dipropargyl 1,10-decanate anddipropargyl terephthalate were synthesized. Properties of these copolymers were characterized by differentialscanning calorimetry and polarizing optical microscopy. The copolymer could be cross-linked easily by UVirradiation in a liquid crystal matrix without adding any photoinitiator. The preliminary studies showed thatthe diacetylene-containing polymer network can assist liquid crystal molecules to align with the externalelectric field, thus reducing the response time of display devices. 展开更多
关键词 Diacetylene-containing copolyesters Polymer-stabilized liquid crystals Electo-optical of liquid crystals
下载PDF
BIODEGRADABLE ALIPHATIC/AROMATIC COPOLYESTERS BASED ON TEREPHTHALIC ACID AND POLY(L-LACTIC ACID):SYNTHESIS,CHARACTERIZATION AND HYDROLYTIC DEGRADATION
11
作者 方征平 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2010年第3期405-415,共11页
Biodegradable aliphatic/aromatic copolyesters, poly(butylene terephthalate-co-lactate) (PBTL) were prepared via direct melt polycondensation of terephthalic acid (TPA), 1,4-butanediol (BDO) and poly(L-lactic ... Biodegradable aliphatic/aromatic copolyesters, poly(butylene terephthalate-co-lactate) (PBTL) were prepared via direct melt polycondensation of terephthalic acid (TPA), 1,4-butanediol (BDO) and poly(L-lactic acid) oligomer (OLLA). The effects of polymerization time and temperature, as well as aliphatic/aromatic moiety ratio on the physical and thermal properties were investigated. The largest molecular weight of the copolyesters was up to 64100 with molecular weight distribution index of 2.09 when the polycondensation was carried out at 230℃ for 6 h. DSC, XRD, DMA and TGA analysis clearly indicated that the degree of crystallinity, glass-transition temperature, melting point, decomposition temperature, tensile strength, elongation and Young's modulus were influenced by the ratio between TPA and OLLA in the final copolyesters. Hydrolytic degradation results demonstrated that the incorporation of biodegradable lactate moieties into the aromatic polyester could efficiently improve hydrolytic degradability of the copolymer even though it still had many aromatic units in the main chains. 展开更多
关键词 Aliphatic/aromatic copolyesters Direct melt polycondensation BIODEGRADABLE
下载PDF
Ultrasonic Mechanical, Dialectical and Morphology Characterizations of Unsaturated Copolyesters and Terpolyesters
12
作者 Momen S. A. Abdelaty 《Open Journal of Applied Sciences》 2017年第12期691-704,共14页
In a previous study we focused on the synthesis of new family of unsaturated copolyesters and terpolyesters by interfacial condensation polymerization. Here, in this study as complementary work of physical characteriz... In a previous study we focused on the synthesis of new family of unsaturated copolyesters and terpolyesters by interfacial condensation polymerization. Here, in this study as complementary work of physical characterizations, we focused on the morphological features using X-ray and SEM investigation. Further, the mechanical properties of solid polymers were also studied by a new technique echo-pulse using ultrasonic impulses. This technique was used for solid polymers to determine the elastic moduli involving, Young’s modulus, shear modulus, bulk modulus and micro-hardness modulus. The statistical relation between different kinds of copolyesters and terpolyesters with Poisson’s ratio (υ) and micro-hardness were shown. The dielectric constant (?) and the electrical resistance (Rp) of the solid copolyesters and terpolyesters including aliphatic, aromatic and azo group in the main chain have been studied at room temperature. Moreover, the relation between frequency and dielectric constant for the selective polymers has been also illustrated. 展开更多
关键词 UNSATURATED copolyesters Terpolyesters ULTRASONIC MECHANICAL DIELECTRIC Morphology
下载PDF
SYNTHESIS AND AVERAGE SEQUENCE LENGTH DETERMINATION OF AROMATIC-ALIPHATIC COPOLYESTERS CONTAINING POLY(ALKYLENE OXALATE)UNITS 被引量:1
13
作者 赵蕴慧 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第2期221-229,共9页
Two series of aromatic-aliphatic random copolyesters(PEBTOXS)with diverse diol ratios have been synthesized by direct melting polycondensation.Two kinds of diols(glycol(EG)and 1,4-butanediol(BD))are used in combinatio... Two series of aromatic-aliphatic random copolyesters(PEBTOXS)with diverse diol ratios have been synthesized by direct melting polycondensation.Two kinds of diols(glycol(EG)and 1,4-butanediol(BD))are used in combination in order to adjust crystallization and tensile properties,and three kinds of diacids(dimethyl terephthalate(DMT),diethyl oxalate(DEOX),and sebacic acid(SA))are involved.~1H-NMR spectra quantify both composition and structure,and show that the final contents in copolyesters appropriate to the ... 展开更多
关键词 Poly(alkylene oxalate) COPOLYESTER SYNTHESIS Average sequence length.
下载PDF
PROPERTIES AND MICROSTRUCTURE OF AROMATIC LIQUID CRYSTALLINE COPOLYESTERS
14
作者 王勇 吴大诚 李瑞霞 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第2期123-128,共6页
The properties and structures of thermotropical liquid crystalline copolyesters based on p-hydroxybenzoic acid (PHBA), terephthalic acid (TPR) and bisphenol A (BPA) were studied by DSC, WAXD, hot stage polarized micro... The properties and structures of thermotropical liquid crystalline copolyesters based on p-hydroxybenzoic acid (PHBA), terephthalic acid (TPR) and bisphenol A (BPA) were studied by DSC, WAXD, hot stage polarized microscopy and NMR. It was found that most of the copolyesters were soluble in many common organic solvents. The copolyesters had low T-m/T-f values and a broad range of liquid crystal phase, making the polymers readily melt-processable. The effects of annealing at different temperatures on the copolyester containing 33% PHBA were also discussed. It was noted that annealing at ca. 200 degrees C (below Tc - n) could lead to the increasing of the crystallinity of the copolyester while the microstructure and sequence structure had not changed. Annealing at ca. 280 degrees C (near Tc - n) could bring a change of crystal and sequence structure and simultaneously made the microdomains be ordered more perfectly. 展开更多
关键词 liquid crystalline copolyester CHARACTERIZATION MICROSTRUCTURE NMR
下载PDF
SYNTHESIS AND CHARACTERIZATION OF AROMATIC LIQUID CRYSTALLINE COPOLYESTERS WITH REGULAR SEQUENCE STRUCTURE
15
作者 林庆煌 王慧芬 +1 位作者 刘德山 周其庠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1990年第3期240-246,共7页
Several novel aromatic liquid crystalline copolyesters with regular sequence structure were prepared by melt Sehotten-Baumann polycondensation via complex monomer. Polarizing microscope with hot stage, thermal analysi... Several novel aromatic liquid crystalline copolyesters with regular sequence structure were prepared by melt Sehotten-Baumann polycondensation via complex monomer. Polarizing microscope with hot stage, thermal analysis and X-ray diffraction were used to investigate the structure and properties of the copolyesters. The effects of structural units, such as flexible spacer, noncolinear meta-linked phenylene unit, crankshaft unit, kink with flexible bridging unit and various substituted benzene rings on melting temperature of aromatic copolyesters were studied and discussed on the basis of crystalline structure of the polymers. 展开更多
关键词 Aromatic copolyester Thermotropic liquid crystal Melting temperature Structural unit
下载PDF
SYNTHESIS AND CHARACTERIZATION OF THERMOTROPIC COPOLYESTERS AND COPOLY (ESTER-AMIDE)S CONTAINING OXYETHYLENE-ETHER AS THE SPACER
16
作者 王尚尔 莫志深 +1 位作者 张宏放 冯之榴 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第4期353-360,共8页
Flexible oxyethylene-ether was introduced into the aromatic copolyesters and copoly (ester-amide)s to reduce the melting point of resulting polymers. The melting point was greatly reduced to 200 degrees C or even lowe... Flexible oxyethylene-ether was introduced into the aromatic copolyesters and copoly (ester-amide)s to reduce the melting point of resulting polymers. The melting point was greatly reduced to 200 degrees C or even lower in some cases, and the molecular weight was satisfactorily high as reflected by inherent viscosity. The polymers exhibited high thermal stability and good mechanical properties as determined by TGA and mechanical tests. The copolyester showed better crystallinity and liquid crystallinity than corresponding copoly (ester-amide)s with similar monomer composition as reflected by POM observation and WAXD study. The melting points for both copolyesters and copoly (ester-amide)s showed great dependence on the p-acetoxybenzoic acid (PAB) content in monomer composition and reached the lowest value when PAB was 29 mol%. 展开更多
关键词 synthesis and comparison liquid crystalline polymer COPOLYESTER copoly(ester-amide)
下载PDF
SYNTHESIS AND CHARACTERIZATION OF MAIN CHAIN AROMATIC LIQUID CRYSTAL COPOLYESTERS WITH X-SHAPED AND ROD-SHAPED MESOGENIC UNITS
17
作者 李自法 李磊 +4 位作者 张淑媛 郑世军 曹少魁 赵丽婷 周其凤 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第1期48-55,共8页
A series of main chain liquid crystal aromatic copolyesters with X-shaped and rod-shaped mesogenic units were synthesized via solution condensation polymerizations of 4,4'-(alpha,omega-octanedioyloxy)-dibenzoyl di... A series of main chain liquid crystal aromatic copolyesters with X-shaped and rod-shaped mesogenic units were synthesized via solution condensation polymerizations of 4,4'-(alpha,omega-octanedioyloxy)-dibenzoyl dichlorides with 2,5-bis(p-octanoxy benzoyloxy)-hydroquinone and diphenol. All of the copolyesters showed thermotropic liquid crystalline behaviors through observations using DSC, polarized microscopy and X-ray diffraction. The melting point (T-m) and the isotropization temperature (T-i) change regularly with varying the content of diphenol unit in the copolymers. 展开更多
关键词 liquid crystal polymer X-shaped and rod-shaped mesogenic units aromatic copolyester synthesis and characterization
下载PDF
OPTICALLY ACTIVE COPOLYESTERS BASED ON AXIALLY DISSYMMETRIC 1,1’-BINAPHTHALENE-2,2’-DIYL UNITS
18
作者 Chuan-fu Chen Min Ai +3 位作者 Zhong Li Hong-wei Liu Ai-jun Gong Fu Xi Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第5期443-447,共5页
Optically active copolyesters based on axially dissymmetric 1,1'-binaphthalene-2,2'-diyl units have been preparedand characterized by specific rotation, ^(13)C-NMR and CD spectra. The results show that the rot... Optically active copolyesters based on axially dissymmetric 1,1'-binaphthalene-2,2'-diyl units have been preparedand characterized by specific rotation, ^(13)C-NMR and CD spectra. The results show that the rotation signs of tribasiccopolyesters or the mixture of corresponding homopolyesters obey a three dimensional quadrant pattern. The composition ofthe copolyesters was determined from ^(13)C-NMR spectra to be triad sequence distributions and corresponding with the ratioby feed. 展开更多
关键词 Optical activity COPOLYESTER 1 1'-Binaphthalene-2 2'-diol Diethyl tartrate
下载PDF
STUDIES ON THE SEQUENCE STRUCTURE OF TPA/EG/PHB LIQUID CRYSTALLINE COPOLYESTERS
19
作者 龚烈忠 王晓工 +1 位作者 刘德山 周其庠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1992年第4期304-310,共7页
In this paper, the sequence structure of TPA/EG/PHB liquid crystalline copolyesters made from different synthetic methods has been studied by;H-NMR with the help of computer program of processing peaks. The results sh... In this paper, the sequence structure of TPA/EG/PHB liquid crystalline copolyesters made from different synthetic methods has been studied by;H-NMR with the help of computer program of processing peaks. The results showed that the ether bonds were not observed in TPA./EG/PHB copolyesters and the synthetic process had a great effect on their sequence structure. Under certain conditions, the high,random TPA/EG/PHB copolyesters which were considered to have higher performances than PET/xPHB could be obtained. 展开更多
关键词 Liquid Crystalline Copolyester PET/xPHB Sequence Structure
下载PDF
PREPARATION OF FUNCTIONAL MATERIALS BY BLENDING COPOLYESTERS WITH PVA AND METAL COMPLEX FORMATION OF POLYMER BLENDS 被引量:1
20
作者 汪水平 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 1998年第1期33-41,48,共9页
Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) ... Copolyesters having secondary and tertiary amine salt groups in the main and side chains are prepared by chemoselective polymerization. These copolyesters are soluble in a 10% aqueous solution of poly(vinyl alcohol) (PVA) at 90 degree C and act as plasticizer in the blend films cast from the solution. Only a glass transition temperature is observed for all these blends indicating the formation of compatible blends from these polyesters with PVA. These blends exhibit manifold characteristics such as ionic conductivity, complex formation with metal ions, absorption of moisture and color changes. The electric conductivity of the copolyesters and blends is in the range of 10** minus **6 Scm** minus **1. The blends with PVA forms complexes with Cu**2** plus and Co**2** plus . The coordination structure with two chelate rings is suggested for these polymer blend/metal complexes. (Author abstract) 10 Refs. 展开更多
关键词 reactive copolyester amine salt group functional polyester PVA blend polymer metal complex ion conductivity coordination structure
全文增补中
上一页 1 2 3 下一页 到第
使用帮助 返回顶部