共聚酯型热熔粘结纤维结晶结构及其熔融行为

采用DSC与WAXD相结合的方法研究了两个系列的无规嵌段共聚酯型热熔粘结纤维的结晶结构并探讨了系列样品的熔融行为.实验表明,以最低熔融温度为界,可将样品分为两组,每组只含一种可结晶单元的结晶.其结构与物理机械性质随该可结晶单元的加入量而有规律的变化.纤维的粘结性能则取决于非晶区结构,非晶区分子链柔性增加,会明显改善粘结效果.     

SYNTHESIS AND CHARACTERIZATION OF AROMATIC LIQUID CRYSTALLINE COPOLYESTERS WITH REGULAR SEQUENCE STRUCTURE

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.     

偏氯乙烯-氯乙烯悬浮共聚物的结晶与熔融性能

研究了聚合温度、共聚物组成、低分子助剂用量等对偏氯乙烯 (VDC) 氯乙烯 (VC)悬浮共聚树脂的结晶度、熔融峰温度的影响 ,并用Florry的聚合物熔点降低理论预测共聚树脂熔点随共聚组成、低分子助剂用量的变化规律 ,为VDC VC悬浮共聚树脂的合成工艺条件和加工性能的改善提供理论基础 .     

含X-型二维液晶基元和反式-4,4′-双(4-羟基苯基偶氮)二苯并-18-冠-6冠醚环的液晶共聚酯的合成与表征

以4,4-′(α,ω己二酰氧)二苯甲酰氯(M1)、2,5-二(对辛氧基苯甲酰氧基)氢醌(M2)和反式4,4′-双(4羟基苯基偶氮)二苯并18冠6(M3)为单体,通过溶液共缩聚反应,合成了一系列含X型二维液晶基元和反式4,4′双(4羟基苯基偶氮)二苯并18冠6冠醚环的主链型液晶共聚酯.共聚酯的分子量不高,[η]在0.37～0.25dL g之间.单体的化学结构通过IR、UV、H NMR、MS和元素分析等方法确证.共聚酯的外观为黄色粉状固体,除CP9外,室温下不溶于CHCl3和THF溶剂.共聚酯的性质采用GPC、[η]、DSC、TG、WAXD和POM等方法进行了研究.发现所有的共聚酯加热到各自的熔融温度以上都能形成液晶态,在液晶态可以观察到近晶相的镶嵌织构或焦锥织构或破扇型织构和向列相的球粒织构或丝状织构或纹影织构.共聚酯的熔融温度(Tm)和各向同性温度(Ti)随共聚酯分子中反式4,4′双(4-羟基苯基偶氮)二苯并18冠6用量的改变呈规律性变化.WAXD研究进一步证实了共聚酯的液晶性.     

涤纶与对乙酰氧基苯甲酸共聚酯的结构和性能的研究

本文对不同组成的涤纶与对乙酰氧基苯甲酸的无规共聚酯(PET-PHB)采用偏光显微镜、电子显微镜、X射线衍射及DSC等技术进行了研究。结果表明,当组成在～30(mol)％ PHB时开始出现热致性液晶,熔体变混浊,此时骤冷样品密度、平衡熔点、开始结晶的过冷程度及过热程度等与组成的关系都出现了突变。提出了液晶相中PHB-PHB链段可能存在以头尾相反方式形成的双链麻花棒按向列型方式排列。     

偏氟乙烯/三氟氯乙烯无规共聚物的结晶

用示差扫描量热法(DSC)、广角X射线衍射(WAXD)和傅里叶红外光谱(FTIR)研究了偏氟乙烯/三氟氯乙烯单体摩尔比为1:4的无规共聚物的结晶与晶体结构.结果表明,该无规共聚物属于半结晶型聚合物.在333～353K温度范围内退火,片晶逐渐完善、增厚,熔点和结晶度均随着退火时间的延长而升高.于353K退火时,由DSC结果计算得到片晶厚度约4.68nm.在333K退火时得到共聚物的最大结晶度约为14%.WAXD测试结果表明,沿晶粒(101)晶面的面间距为0.55nm,垂直于(101)衍射晶面方向上的晶粒平均尺寸为5.86nm.     

SYNTHESIS AND PROPERITIES OF SHISH-KEBAB-TYPE LIQUID CRYSTALLINE POLY（p-PHENYLENE）S

Abstract The novel shish-kebab-type liquid crystalline poly（p-phenylene）s were synthesized through Suzuki coupling reaction from 2,5-bis[（4-n-alkoxyl）benzoyloxy]1,4-dibromobenzene （monomer 1） and 1,4-benzenediboronic acid bistrimethylene cyclic ester （monomer 2）. Their structure and properties were characterized by GPC, DSC, X-ray diffraction and polarizing optical microscope （POM）. It was found that the polymers turned to liquid crystalline phase above their melting point. The melting point （Tm） of the polymers decreases when the length of the alkoxy tails of the mesogenic units increases. The mesophase was identified by X-ray diffraction method. The polymers could dissolve in common organic solvents and show strong blue fluorescence. The maximum absorption bands of polymers prepared from annealed films have large red-shift due to the spontaneous orientation of the liquid crystalline side chains. The same phenomena were also observed in the fluorescence spectra.     

Degradable Polymers. III. Synthesis and Characterization of Aliphatic Thermoplastic Block Copolyesters

A group of new block copolymers has been synthesized and characterized. The copolyesters were step-polymerized with six different poly-ether feeds, ranging from 21.1 to 53.3 mol%. The resulting polyethylene succinate)-b-poly(tetramethylene glycol) (PES/PTMG) polymers were characterized by GPC, DSC, IR, and NMR, and tensile strength measurements were performed. The molar composition of the polymers was determined by NMR and also correlated with IR. The compositions of the polymers agree well with those expected from the composition of the feed. Fibers for tensile strength measurements were extruded, and samples for dynamic mechanical tests (DMTA) were compression molded. The crystallinity, the melting temperature, the fiber strength, and the elastic bending modulus decreased with increasing polyether content, whereas the breaking strain increased.     

Synthesis and thermal properties of poly(arylene ether ketone)s containing phthalazinone moieties

A series of novel poly(arylene ether ketone)s were synthesized from the reaction of hydroquinone and 4-(4-hydroxyphenyl)-2,3-phthalazin-1-one with 4,4′-difluorobenzophenone in N-cyclohexylpyrrolidinone containing anhydrous potassium carbonate. The polymers exhibited high glass transition temperatures together with excellent thermooxidative stability. The chain structure of these polymers was studied by means of differential scanning calorimetry (DSC), wide-angle X-ray diffraction techniques (WAXD), and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The experimental results indicated that these “as-made” copoly(aryleneketone)s containing hydroquinone moieties exhibited a block chain structure with segments which mainly consisted of hydroquinone and 4,4′-difluorobenzophenone. These chain segments resulted in crystallites in the polymers although they are thermodynamically unstable. The polymers showed thermal properties comparable to commercial PEEK, but the conditions for synthesis are much milder. The glass transition temperatures and solubilities of the copoly(arylene ketone)s tended to increase with increasing phthalazinone moiety content, while the crystallite melting points and crystallinity appeared to decrease. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1781–1788, 1999     

SYNTHESIS, CHARACTERIZATION AND NANOPARTICLE FORMATION OF STAR-SHAPED POLY(L-LACTIDE) WITH SIX ARMS

Well-defined star-shaped poly(L-lactide)with six arms(sPLLA)was synthesized via the ring-opening polymerization of L-lactide using dipentaerythritol as initiator and stannous octoate as catalyst in bulk at 125~C.The effects of molar ratios of both monomer to initiator and monomer to catalyst on the molecular weights of as-synthesized sPLLA polymers were in detail investigated.The molecular weights of sPLLA polymers linearly increased with the molar ratio of monomer to initiator,and the molecular weight d...     

Synthesis and characterization of side chain liquid crystalline polymers exhibiting cholesteric and blue phases

A series of cyclosiloxane-based cholesteric liquid crystalline (LC) polymers were synthesized from a cholesteric LC monomer cholest-5-en-3-yl(3β) 4-(2-propenyloxy)benzoate and a nematic LC monomer butyl 4-[4-(2-propenyloxy)benzoxy]benzoate. All the polymers exhibit thermotropic LC properties and show cholesteric phases. Most of the polymers display four types of phase transition behaviour corresponding to glass transition, melting point, cholesteric phase-blue phase transition and clearing point. The mesophase temperature range of the blue phases are as broad as 20°C. The blue phase was confirmed by the apperance of planar textures and cubic packings. With an increase of non-chiral component in the polymers, the clearing point decreases slightly, while the glass transition and melting temperatures change little. In the reflection spectra of the polymer series the reflected wavelength broadens and shifts to longer wavelength with increase of the non-chiral component in the polymer systems, suggesting that the helical pitch P lengthens.     

STUDIES ON THERMOTROPIC LIQUID CRYSTALLINE COPOLYESTERS——POLY (ARYLENE TEREPHTHALATE-CO-BUTYLENE TEREPHTHALATE)

A series of copolyesters based on bis(4-hydroxybutyl) terephthalate, terephthaloyl chloride andvarious aromatic diols (i.e. hydroquinone, chlorohydroquinone, bromohydroquinone or dihydroxybi-phenyl) was prepared. ~1H-NMR studies revealed that the monomer units had microstructures closeto random distribution in the chains. The copolymers showed composition-dependent liquid crystal-line properties as verified by visual observation of stir opalescence, polarizing microscope, DSC andX-ray diffration. The copolyesters with aromatic diol contents over a certain extent (for chloro-hydroquinone m≥0.33) were thermotropic with wide liquid crystalline temperature ranges. Theintroduction of chlorohydroquinone into the copolyesters could gradually destroy the crystallinityof the polymers but retain the liquid crystalline characteristics.     

非晶聚对苯二甲酸乙二酯的制备与表征

通过单体酯交换法和聚 2 ,6 萘二甲酸乙二酯 (PEN)与低分子量PET酯交换的方法分别合成了一系列NPA/TPA/EG和IPA/TPA/EG共聚酯 .随着NPA或IPA单元含量的增加 ,等温结晶速度迅速降低 ,共聚物的结晶性降低甚至非晶化 .由NMR分析得知单体酯交换法与聚合物酯交换法得到的共聚酯NPA/TPA/EG序列分布相近 ,链结构都接近完全无规 .由DSC结果分析 ,随共聚单体含量的增加 ,熔点和熔融热降低 ,结晶度也随之降低 .当NPA或IPA含量达到 2 0 %时 ,可以得到非晶的共聚酯 (APET) .本文还对共聚物组成与结晶温度的关系进行了表征     

含氧单体和1－烯烃配位共聚合研究及共聚物表征

考察了极性含氧单体，４－戊烯氧基三甲基硅烷（ＰＴＭＳ）在络合Ⅱ型ＴｉＣｌ３－Ａｌ（ｉ－Ｃ４Ｈ９）３催化体系下与丙烯共聚合情况．通过脱三甲基硅保护基，合成了丙烯，戊烯醇共聚物，并用ＩＲ，ＮＭＲ等方法进行表征．详细考察了Ａｌ／Ｔｉ比，温度等聚合条件对共聚合的影响．初步研究了共聚合的动力学行为．此外，还发现丙烯，戊烯醇共聚物保持了较好的物理性质，如较高的熔点，等规度，抗降解能力，粘接性等，为聚烯烃功能化提供了一条新的途径．     

Synthesis and characterization of biodegradable poly(butylene succinate-co-butylene fumarate)s

A series of aliphatic biodegradable polyesters modified with fumaric residues was synthesized by transesterification in the melt of dimethyl succinate, dimethyl fumarate and 1,4-butanediol. The amount of unsaturation, originating from the fumaric acid residues in the polyesters chains was varied from 5 to 20 mol%. The molecular structure and composition of the polyesters were determined by ¹H NMR spectroscopy. The effects of the content of fumaric residues on the thermal and thermo-oxidative properties of the synthesized polyesters were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis. The degree of crystallinity was determined by DSC and wide angle X-ray scattering. The degrees of crystallinity of the unsaturated copolyesters were reduced, while the melting temperatures were higher in comparison to poly(butylene succinate). Biodegradation of the synthesized copolyesters was estimated in enzymatic degradation tests using a buffer solution with Rhizopus arrhizus lipase at 37 °C. Although the degree of crystallinity of the copolyesters decreases slightly with increasing unsaturation, the biodegradation is not enhanced suggesting that not only the chemical structure and molecular stiffness but also the morphology of the spherulites has an influence on the biodegradation properties. The highest biodegradability was observed for the copolyesters containing 5 and 10 mol% of fumarate units.     

含X-型二维液晶基元和顺式-4,4′-双(4-羟基苯基偶氮)二苯并-14-冠-4冠醚环液晶共聚酯的合成与表征

以4,4′-(α,ω-辛二酰氧)二苯甲酰氯(M1)、2,5-二(对十二烷氧基苯甲酰氧基)对苯二酚(M2)和顺式-4,4′-双(4-羟基苯基偶氮)二苯并-14-冠-4(M3)为单体,通过溶液共缩聚反应,合成了一系列含X-型二维液晶基元和顺式-4,4′-双(4-羟基苯基偶氮)二苯并-14-冠-4冠醚环的主链型液晶共聚酯.单体1(M1)由对羟基苯甲酸和辛二酰氯,通过酯化和取代反应制备,单体2(M2)由2,5-二羟基苯醌和对十二烷氧基苯甲酰氯通过酯化和还原反应制备,单体3(M3)由顺式-二氨基二苯并-14-冠-4和苯酚通过重氮化和偶联反应制备.共聚酯的分子量不高,[η]在0·35~0·25dL/g之间.单体的化学结构通过IR、UV、1H-NMR、MS和元素分析等方法确证.共聚酯的外观为黄色粉状固体,除CP9外,室温下不溶于CHCl3和THF溶剂.共聚酯的性质采用GPC、[η]、DSC、TG、WAXD和POM等方法进行了研究.发现所有的共聚酯加热到各自的熔融温度以上都能形成液晶态,在液晶态可以观察到向列相的丝状织构或纹影织构.共聚酯的熔融温度(Tm)和各向同性温度(Ti)随共聚酯分子中顺式-4,4′-双(4-羟基苯基偶氮)二苯并-14-冠-4用量的改变呈规律性变化.WAXD研究进一步证实了共聚酯的液晶性.     

Crystallization and melting behavior of liquid crystalline copolyesters based on poly(ethylene terephthalate)

A series of copolyesters were prepared by the incorporation of p‐hydroxybenzoic acid (HBA), hydroquinone (HQ), and terephthalic acid (TA) into poly(ethylene terephthalate) (PET). On the basis of viscosity measurements, high molar mass copolyesters were obtained in the syntheses, and ¹H‐NMR analyses indicated the total insertion of comonomers. They exhibit nematic phase above melting temperature, as observed by polarized light microscope (PLM). Their crystallization and melting behaviors were also studied by differential scanning calorimetry (DSC) and wide angle X‐ray diffraction (WAXD). It was found that these copolyesters are more crystalline than copolyesters prepared from PET and HBA. Introduction of HQ/TA disrupts longer rigid‐rod sequences formed by HBA, and thus enhances molecular motion and increases crystallization rate and crystallinity. Isothermal crystallization at solid phase polymerization conditions (up to 24 h at 200°C) resulted in increased copolymer randomness (by NMR) and higher melting point, the latter attributed to structural annealing. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 369–377, 1999     

Biodegradable aliphatic/aromatic copolyesters based on terephthalic acid and poly(L-lactic acid): Synthesis, characterization and hydrolytic degradation

<正>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.     

含间苯基聚芳醚酮的合成与性能研究

含间苯基聚芳醚酮的合成与性能研究林权，张万金，吴忠文，尹玖梅（吉林大学化学系，长春，１３００２１）（中国科学院长春应用化学研究所）关键词聚芳醚酮，间苯基，熔点，结晶度聚芳醚酮作为一类耐高温特种工程塑料，由于具有优异的热、电、机械性能，已被广泛应用于电...     

含氧单体和1－烯烃配位共聚合研究及共聚物表征

考察了极性含氧单体，４－戊烯氧基三甲基硅烷（ＰＴＭＳ）的络合Ⅱ型ＴｉＣｌ３Ａｌ（ｉ－Ｃ４Ｈ９）３催化体系下与丙烯共聚合情况，通过脱三甲基硅保护基，合成了丙烯，戊烯醇共聚物，并用ＩＲ，ＮＭＲ等方法进行表征，详细考察了Ａｌ／Ｔｉ比，温度等聚合条件对共聚合的影响。初步研究了共聚合的动力学行为，此外，还发现丙烯，戊烯醇共聚物保护了较好的物理性质，如较高的熔点，等规度，抗降解能力，粘接性等，为聚烯烃功能化提