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SYNTHESES AND CHARACTERIZATION OF A NEW TYPE OF LIQUID CRYSTALLINE POLYESTERS
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作者 白如科 吴承佩 +3 位作者 邹应芳 孙武 潘才元 Toshiyuki Uryu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1994年第3期221-227,共7页
A new type of liquid crystalline polyesters with resorcin as one part of the mesogenic unitconnected together by polymethylene, or phenylene group, and lateral groups consisting of arigid azobenzene as another part of... A new type of liquid crystalline polyesters with resorcin as one part of the mesogenic unitconnected together by polymethylene, or phenylene group, and lateral groups consisting of arigid azobenzene as another part of the mesogenic unit were synthesized by interfacialpolymerization of diacyl chlorides in 1, 2-dichloroethane and 2, 4-dihydroxy-4'-nitroazobenzen inaqueous alkaline solution. The polyester structures were confirmed by proton NMR and IRspectra. Their phase transition behavior and texture were studied by polarizing microscopy andDSC. 展开更多
关键词 New liquid crystalline polyesters SYNTHESIS Interfacial polymerization Phase transition temperature Texture of liquid crystalline polymers
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Compatibilization of PBT/PP Blends by Adding Side-chain Liquid Crystalline Ionomer with Quaternary Pyridinium Groups 被引量:3
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作者 XU Xin-yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期140-144,共5页
A side-chain liquid crystalline ionomer(SLCI) was synthesized by grafting copolymerization of 4-(4-ethoxybenzoyloxy)-4'-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blend... A side-chain liquid crystalline ionomer(SLCI) was synthesized by grafting copolymerization of 4-(4-ethoxybenzoyloxy)-4'-allyloxybiphenyl and N-allyl-pyridium bromide on polymethylhydrosiloxane. The SLCI was blended with polypropylene(PP) and polybutylene terephthalate(PBT) by melt mixing. The thermal behavior, liquid crystalline properties, morphological structure, and mechanical properties of the blends were investigated by differential scanning calorimetry(DSC), polarizing optical microscopy(POM), scanning electron microscopy(SEM), and tensile measurement. When a proper amount of SLCI was added, fine configurations were formed in the PBT/PP/SLCI blend system, and the mechanical properties were improved due to improved adhesion at the interface. When excess SLCI was added, an inhomogeneous structure resulted, which caused the mechanical properties to deteriorate. 展开更多
关键词 Poly(butylent terephthalate) Poly(propylene) liquid crystalline ionomer COMPATIBILIZATION
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Synthesis and characterization of H-type amphiphilic liquid crystalline block copolymers by ATRP 被引量:2
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作者 Xin De Tang Long Cheng Gao +1 位作者 Xing He Fan Qi Feng Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第2期237-240,共4页
H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization (ATRP). Macroinitiators prepared by the esterification between poly(ethylene ox... H-type amphiphilic liquid crystalline block copolymers containing azobenzene were synthesized by atom transfer radical polymerization (ATRP). Macroinitiators prepared by the esterification between poly(ethylene oxide) (PEG) and 2,2-dichloroacetyl chloride were utilized to initiate the polymerization of 6-[4-(4-ethoxyphenylazo)phenoxy]hexyl rnethacrylate (M6C). The resulting macroinitiators and block copolymers were characterized by ^1H NMR, gel permeation chromatography (GPC). Polarizing optical microscopy (POM) and differential scanning calorimetry (DSC) preliminarily revealed the liquid crystalline property of these block copolymers. This series of liquid crystalline block copolymers are promising in some areas, such as optical data storage, optical switch, and molecular devices. 展开更多
关键词 H-type Amphiphilic Block copolymer liquid crystalline property Atom transfer radical polymerization (ATRP)
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Effect of spacer length on the liquid crystalline property of azobenzene-containing ABA-type triblock copolymers via ATRP 被引量:2
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作者 Xin De Tang Long Cheng Gao +1 位作者 Xing He Fan Qi Feng Zhou 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1129-1132,共4页
The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl... The effect of flexible spacer length on the liquid crystalline property of ABA-type triblock copolymers containing azobenzene groups was investigated. For the study, the monomers, n-[4-(4-ethoxyphenylazo)phenoxy]alkyl methacrylates with varying methylene groups (n = 0, 2, 6) were used to synthesize a series of azobenzene-containing amphiphilic triblock copolymers PAnC–PEG–PAnC by atom transfer radical polymerization (ATRP). Differential scanning calorimetry (DSC), polarizing optical microscopy (POM), and one-dimensional X-ray diffraction (1D WAXD) have shown that the glass transition temperatures of these copolymers decreased with increasing n, PA0C–PEG–PA0C has no mesophase, while both PA2C–PEG–PA2C and PA6C–PEG–PA6C have a nematic mesophase. These differences derive from the length of spacer groups between the polymer backbone and side-chain LC monomers. 展开更多
关键词 Spacer group liquid crystalline property AZOBENZENE Triblock copolymer Atom transfer radical polymerization (ATRP)
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SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANES CONTAINING CROWN ETHER AND BENZYL ETHER MOIETIES 被引量:2
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作者 戴荣继 傅若农 佟斌 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1998年第1期18-24,共7页
Two kinds of side chain liquid crystalline polysiloxanes containing crown ether and benzyl ether were synthesized and characterized by optical polarization microscopy. Both the monomeric liquid crystals and polymeric ... Two kinds of side chain liquid crystalline polysiloxanes containing crown ether and benzyl ether were synthesized and characterized by optical polarization microscopy. Both the monomeric liquid crystals and polymeric liquid crystals show smectic phases. 展开更多
关键词 liquid crystalline polysiloxane side chain crown ether benzyl ether mesogens
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Synthesis,liquid crystalline and luminescent properties of trimeric phenylenevinylene with end-groups of(R)-(+)-2-methylbutyric acid ester 被引量:1
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作者 Cheng Bo Zhang Ying Li +4 位作者 Wen Ke Liu Hai Quan Zhang Huai Yang Qing Shan Li Guang Zhong Xing 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第12期1423-1426,共4页
The trimeric phenylenevinylene with the symmetrical chiral end-groups (ChTPV) was synthesized. The liquid crystalline and luminescent properties of the ChTPV have been studied by differential scanning calorimetry (... The trimeric phenylenevinylene with the symmetrical chiral end-groups (ChTPV) was synthesized. The liquid crystalline and luminescent properties of the ChTPV have been studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM), absorption and photoluminescence spectra. The results indicated that the ChTPV exhibits mesophase over a wide temperature range and a typical optical texture of smectic phase. In contrast with the spectra of the solution, that of the film showed blue-shift in maximal absorption and red-shift in maximal emission due to H-type aggregation with parallel alignment of the TPV transition dipole moment. 展开更多
关键词 Trimeric phenylenevinylene Chiral SYNTHESIS liquid crystalline Luminescence H-type aggregation
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SYNTHESIS AND CHARACTERIZATION OF TRIAZOLE CONTAINING LIQUID CRYSTALLINE POLYMERS THROUGH 1,3-DIPOLAR CYCLOADDITION POLYMERIZATION 被引量:1
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作者 Devamani Srividhya Sundaram Manjunathan +2 位作者 Sivashankaran Nithyanandan Subramanan Balamurugan Sengodan Senthil 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第6期761-770,共10页
Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were c... Liquid crystalline polymers containing 1,2,3-triazole units as linking groups have been synthesized from the monomers containing triad ester diazide and flexible dialkyne ester by 1,3-cycloaddition reaction and were characterized. Click reaction of azide and alkyne functionals catalyzed by Cu(I) yielded target polyesters with 1,2,3-triazole groups.The structure of the polymer was confirmed by spectral techniques.GPC analysis reveals that the polymers have moderate molecular weight with narrow distribution.H... 展开更多
关键词 TRIAZOLE Click chemistry Main chain polymers Azide-alkyne cycloaddition liquid crystalline polymers
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STABILITY OF EQUILIBRIA OF NEMATIC LIQUID CRYSTALLINE POLYMERS 被引量:1
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作者 Hong Zhou Hongyun Wang 《Acta Mathematica Scientia》 SCIE CSCD 2011年第6期2289-2304,共16页
We provide an analytical study on the stability of equilibria of rigid rodlike nematic liquid crystalline polymers (LCPs) governed by the Smoluchowski equation with the Maier-Saupe intermolecular potential. We simpl... We provide an analytical study on the stability of equilibria of rigid rodlike nematic liquid crystalline polymers (LCPs) governed by the Smoluchowski equation with the Maier-Saupe intermolecular potential. We simplify the expression of the free energy of an orientational distribution function of rodlike LCP molecules by properly selecting a coordinate system and then investigate its stability with respect to perturbations of orientational probability density. By computing the Hessian matrix explicitly, we are able to prove the hysteresis phenomenon of nematic LCPs: when the normalized polymer concentration b is below a critical value b* (6.T314863965), the only equilibrium state is isotropic and it is stable; when b* 〈 b 〈 15/2, two anisotropic (prolate) equilibrium states occur together with a stable isotropic equilibrium state. Here the more aligned prolate state is stable whereas the less aligned prolate state is unstable. When b 〉 15/2, there are three equilibrium states: a stable prolate state, an unstable isotropie state and an unstable oblate state. 展开更多
关键词 EQUILIBRIA STABILITY nematic liquid crystalline polymers hysteresis phenomenon
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Modification of Interfacial Interaction of PBT/PP Blends by Adding Main-chain Liquid Crystalline Ionomer with Sulfonic Group 被引量:1
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作者 XU Xin-yu ZHANG Fan XIE Bing-xi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第2期340-344,共5页
A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLC... A main-chain liquid crystalline ionomer(MLCI) containing sulfonic group was synthesized by an interfacial condensation reaction.The MLCI was blended with polybutylene terephthalate(PBT) and polypropylene(PP).MLCI interacted with both the dispersed(PP) phase and the matrix(PBT) phase to modify the interfacial interaction of PBT and PP.Differential scanning calorimetry(DSC),scanning electron microscopy(SEM) and FTIR imaging system analysis demonstrated the significance of interfacial interaction in the polymer blends.MLCI brought about good adhesion at the interfacial,which reduced the disperse phase size and enabled a fine PP phase at matrix.The mechanical properties of the ternary blends were improved when a proper amount of MLCI was added.This was attributed to enhanced adhesion at the interface,which invoked better mechanical properties in the blends. 展开更多
关键词 Poly(butylent terephthalat) POLYPROPYLENE Main-chain liquid crystalline ionomer Sulfonic group Interfacial interaction
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Synthesis and Characterization of New UV-curable Liquid CrystallineDiacrylates 被引量:1
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作者 HongBoLIU MingCaiCHEN +1 位作者 ZhiTangHUANG KaiXU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期639-640,共2页
A series of UV-curable liquid crystalline diacrylates were synthesized by using 4, 4'-(terephthaloyldioxy) dibenzoic acid as a mesogen unit.
关键词 liquid crystalline diacrylates synthesis mesogen unit.
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CHOLESTERIC LIQUID CRYSTALLINE CHARACTER ON THE SURFACE OF CHITOSAN/POLYACRYLIC ACID COMPOSITES
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作者 Yan-ming Dong Yu-song Wu Mian Wang Department of Materials Science & State Key Laboratory for Physical Chemistry of Solid Surfaces, Xiamen University Xiamen 361005, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第3期247-253,共7页
The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surfac... The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surface by both scanning electron microscopy (SEM) and atomic force microscopy (AFM), instead of the thumb-print texture which can be detected with polarized optical microscopy. It is suggested that the periodical lamellar-like structure is induced by the etching selectivity between cholesteric layers due to different molecular arrangement on the film surface. Four kinds of perpendicular disclinations, i.e. chi --> tau (-) + lambda (+), chi --> lambda (-) + tau (+), chi --> tau (-) + tau (+) and chi --> lambda (-) + lambda (+) were found in the composite films from SEM observations. The smallest periodicity of lamellar-like structure (equals to half pitch) is 20 similar to 40 nm measured with AFM. 展开更多
关键词 CHITOSAN cholesteric order liquid crystalline fingerprint texture lamellar structure SEM AFM
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SYNTHESIS AND PROPERTIES OF NEW MESOGEN-JACKETED LIQUID CRYSTALLINE POLYMERS
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作者 Qi-ding Mi Qi-feng Zhou Department of Polymer Science & Engineering, College of Chemistry Peking University, Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第2期139-148,共10页
Some new mesogen-jacketed liquid crystalline polymers (MJLCP) with polymer backbones, spacers, and mesogenic units of different structures were synthesized by radical polymerization. The mesomorphic behavior of these ... Some new mesogen-jacketed liquid crystalline polymers (MJLCP) with polymer backbones, spacers, and mesogenic units of different structures were synthesized by radical polymerization. The mesomorphic behavior of these polymers was examined using differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Their liquid crystallinity is influenced by the variation of polymer backbone, spacer, mesogenic unit and its terminal groups. The results show that 1) a more flexible polymer main-chain is more favorable to the formation of a liquid crystal phase, while 2) a flexible spacer will decrease the 'Jacket Effect' and the liquid crystallinity and 3) a subtle modification of the terminal groups on the mesogenic unit may also have a significant influence on properties of the polymers. 展开更多
关键词 mesogen-jacketed liquid crystalline polymers polymer backbones SPACERS mesogenic units liquid crystallinity
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MECHANICAL PERTURBATION INDUCED MOLECULAR ALIGNMENTS IN A SIDE-CHAIN LIQUID CRYSTALLINE POLYACETYLENE, POLY{10-[4-(4'-METHOXYPHENOXY-CARBOML)PHENOXYCARBONYL]-1-DECYNE}
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作者 Ben-zhong Tang Xiang-xing Kong Xin-de Feng Department of Chemistry, Hong Kong University of Science & Technology, Clear Water Bay, Kowloon, Hong Kong, China Department of Polymer Science & Engineering, College of Chemistry, Peking University, Beijing 100871, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第3期289-294,共6页
A new liquid crystalline polyacetylene containing a phenyl benzoate mesogen (5) is synthesized,whose mesomorphic properties are found to be easily 'tunab1e' by simple mechanical perturbation. Thepolymerization... A new liquid crystalline polyacetylene containing a phenyl benzoate mesogen (5) is synthesized,whose mesomorphic properties are found to be easily 'tunab1e' by simple mechanical perturbation. Thepolymerization of 10- [ 4 - (4' -methoxyphenoxycarbonyl )phenoxycarbonyl] - 1 -decyne (4 ) in itiated by theWCl_6-Ph_4Sn/dioxane complex yields polymer 5 with a M_w of 28400. The molecular structure of 5 ischaracterized by NMR, IR, and UV spectroscopy and its liquid crystalline behavior is investigated by DSC,POM, and XRD analysis. Upon mechanical perturbation, 5 exhibits unusual agitation-induced high-strengthdisclinations, shear-induced inversion walls, and solidification-induced banded textures. Such phenomenahave been observed in the main-chain liquid crystalline polymers with rigid backbones, but have seldom beenreported for the side-chain liquid crystalline polymers with flexible backbones, suggesting that the rigidpolyacetylene backbone of 5 plays a constructive role in inducing the novel molecular alignments. 展开更多
关键词 liquid crystals Side-chain liquid crystalline polymers POLYACETYLENES High-strength disclinations Inversion walls Banded textures Molecular alignments
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STUDY ON THE BLENDS OF NYLON 66 AND LIQUID CRYSTALLINE POLYESTERS
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作者 张树范 任京红 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第4期302-306,共5页
Blends of polyamide (Nylon 66) with two different kinds of liquid crystalline polyesters were studied in all the composition range. Homogeneous samples were obtained by coprccipitation from 2 wt%. solution of blends. ... Blends of polyamide (Nylon 66) with two different kinds of liquid crystalline polyesters were studied in all the composition range. Homogeneous samples were obtained by coprccipitation from 2 wt%. solution of blends. The thermal properties, crystallinity and morphology of these blends were studied by using DSC, polarizing microscopy, and scanning electron microscopy. The phase transition and morphology of the blends are markedly-influenced by the composition of liquid crystalline polyesters. The mechanical behaviour of PHB/HNA-Nylon 66 blend was improved. although polyamidc (Nylon 66)with the liquid crystalline polyesters were incompatible, but a rather strong interaction between the polymers did exist. 展开更多
关键词 liquid crystalline polyester BLEND POLYAMIDE Phase transition Morphology.
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MORPHOLOGICAL STUDY ON THE ORIENTED CHITOSAN FILM OBTAINED FROM PRE-SHEARED LIQUID CRYSTALLINE SOLUTION IN DICHLOROACETIC ACID
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作者 Zhong-ming Hu Li-heng Wu +1 位作者 Da-cheng Wu Shou-xi Chen State Key Laboratory of Polymer Physics and Chemistry, Center for Molecular Science, Institute of Chemistry Chinese Academy of Sciences, Beijing 100080, China China Textile Academy Beijing 100025, China Textile College, Sichuan University Chengdu 610065, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2001年第4期385-390,共6页
The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA) solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), in... The oriented chitosan films obtained from pre-sheared liquid crystalline chitosan/dichloroacetic acid (DCA) solutions were studied by means of polarized optical microscopy (POM), scanning electron microscopy (SEM), infra-red dichroism technique and wide angle X-ray diffraction (WAXD). The sheer induced band texture in the film was found to correspond to the sinusoidal fibrillar microstructure along the shearing direction on the basis of POM and SEM observations. The sinusoidal fibril was found to be lying within the film plane. The model of chitosan molecular orientation in the pre-sheared film with band texture can be established assuming that the main chain orients in the shearing direction and the side group is perpendicular to the shearing direction. The WAXD azimuthal scanning at 2 theta = 20 degrees indicates that the (002) plane orients perpendicular to the shearing direction. 展开更多
关键词 CHITOSAN morphology ORIENTATION shear induced band texture liquid crystalline solution
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INFLUENCE OF MOLECULAR WEIGHT OF CHITIN AND ITS THREE DERIVATIVES ON CRITICAL CONCENTRATION OF LYOTROPIC LIQUID CRYSTALLINE PHASE TRANSITION
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作者 Yan-ming Dong Jian-wei Wang Qing Yuan Department of Materials Science, Xiamen University, Xiamen 361005, China 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2000年第1期15-17,共3页
The critical concentration of lyotropic liquid crystalline phase transition for chitin derivatives was determined using a polarization microscope. The influence of molecular weight on critical concentration of liquid ... The critical concentration of lyotropic liquid crystalline phase transition for chitin derivatives was determined using a polarization microscope. The influence of molecular weight on critical concentration of liquid crystalline solution for chitin, chitosan, cyanoethyl chitosan and propionyl chitin successively increases as the chain rigidity decreases. Therefore it can be used as an indicator of the chain rigidity. 展开更多
关键词 CHITIN CHITOSAN lyotropic liquid crystalline polymer critical concentration molecular weight
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EFFECT OF DRAWING ON MORPHOLOGY,STRUCTURE AND MECHANICAL PROPERTIES OF BLENDS OF A LIQUID CRYSTALLINE POLYMER AND MODIFIED POLY(PHENYLENE OXIDE)
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作者 刘松林 沈静姝 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1997年第3期273-281,共9页
Polymer strands with various draw ratios of a thermotropic liquid crystalline polymer (LCP) and modified poly(phenylene oxide) were prepared by drawing the melts leaving a slit die in open air. The morphology, structu... Polymer strands with various draw ratios of a thermotropic liquid crystalline polymer (LCP) and modified poly(phenylene oxide) were prepared by drawing the melts leaving a slit die in open air. The morphology, structure and mechanical properties of the resulting strands were studied as a function of LCP content and draw ratio. It was found that the thermal and mechanical properties of the matrix phase did not change dramatically with the amount of LCP and draw ratio, but the orientation of LCP phase could be increased with draw ratio. The mechanical properties of the strands could be improved by moderately drawing the melts. Wide angle X-ray diffraction suggested that the improvement in tensile strength of the strands was due to the resultant fibrillation of LCP phase and enhanced molecular orientation. Morphological observation indicated that excessive drawing of the strands could lead to the break down of the microfibrils of LCP and thus resulted in the decrease of mechanical strength. 展开更多
关键词 modified poly(phenyleneoxide) liquid crystalline polymer drawing of blends MORPHOLOGY mechanical properties
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PROPERTIES AND MICROSTRUCTURE OF AROMATIC LIQUID CRYSTALLINE COPOLYESTERS
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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
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PREPARATION AND CHARACTERIZATION OF SHISH-KEBAB TYPE LIQUID CRYSTALLINE POLY(p-PHENYLENEVINYLENE)
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作者 Kazuo Akagi 郑世军 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2006年第4期353-361,共9页
Novel shish-kebab type liquid crystalline poly(p-phenylenevinylene) derivatives were synthesized by Stille coupling reaction from 2,5-bis[(4-n-alkoxyl)benzoyloxy]1,4-dibromobenzene (monomer l) and 1,2-bis(tribu... Novel shish-kebab type liquid crystalline poly(p-phenylenevinylene) derivatives were synthesized by Stille coupling reaction from 2,5-bis[(4-n-alkoxyl)benzoyloxy]1,4-dibromobenzene (monomer l) and 1,2-bis(tributylstannyl) ethylene (monomer 2). The polymers with alkoxy groups are soluble in common organic solvents and exhibit blue fluorescence. Both the cast film and the annealed film have large red-shifts in fluorescence spectra and show yellow fluorescence. The polymers with CN and NO2 groups show poor solubility and green fluorescence. All the polymers possess liquid crystalline smectic phases. The melting point (Tm) of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The polymers are easily aligned under a magnetic field of 10 Tesla. It is found that the conjugated backbone and LC side chain are aligned perpendicular and parallel to the magnetic field, respectively. The polymers show optical dichroism in fluorescence spectra, suggesting that they are available for advance materials with linear optical polarization. 展开更多
关键词 liquid crystalline conjugated polymers Poly(p-phenylenevinylene) SHISH-KEBAB Linearly polarized dichroism Fluorescence.
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SYNTHESIS OF LIQUID CRYSTALLINE POLYACRYLATES WITH THIOESTER AS BRIDGE-BOND
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作者 张维邦 张国栋 +1 位作者 许家瑞 曾汉民 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1996年第2期120-126,共7页
A new series of acrylates with the same mesogens containing thioester as bridge-bond were synthesized, and the acrylates were characterized by H-1 NMR, IR and MS. The polymers were obtained by radical polymerization u... A new series of acrylates with the same mesogens containing thioester as bridge-bond were synthesized, and the acrylates were characterized by H-1 NMR, IR and MS. The polymers were obtained by radical polymerization using AIBN as initiator. The monomers and polymers exhibit thermotropic-enantiotropic Liquid crystalline behavior. 展开更多
关键词 THIOESTER bridge-bond liquid crystalline polymers positive dielectric anisotropy
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