含热致液晶性共聚酯的聚砜共混物

将一种含萘环的热致液晶性共聚酯与聚砜材脂熔融共混并挤塑成条．毛细管流变性测试表明，这一共聚酯降低了共混物的表观粘度，甚至低于其本身的粘度．共混物受剪切作用形成了各向异性的微纤增强结构，并具有皮芯结构．在液晶聚合物含量低到２％与０．５％的样条中仍有共聚酯微纤形成．共聚酯微纤提高了聚砜的力学性能，含２０％共聚酯共混物挤塑条的位伸模量为聚砜树脂的二倍半．     

以热致液晶聚合物微纤增强的原位复合材料

用４种热致液晶聚合物分别与聚丙烯,聚对苯二甲酸丁二酯,聚碳酸酯,聚醚砜和聚砜搭配,在各聚合物对的“加工窗口“温度范围内熔融共混并挤塑得到６种共混物。藉流变仪,扫描电子显微镜,偏光显微镜,动态力学谱仪等重点研究了原位复合材料中微纤结构的形成,组分特性,熔体粘度,挤塑温度和浓度等因素对各向异性结构形成的贡献,以及液晶聚合物对聚合物结晶的诱导作用和两相间的相互作用。     

热致液晶共聚酯对聚丙烯结晶的诱导作用

用差示扫描量热法和光学解偏振法研究了热致液晶性芳香共聚酯与聚丙烯共混物的等温和非多温结晶行为.结果表明,这一热致液晶聚合物对聚丙烯结晶有诱导成核和加速作用.当共聚酯含量在2-5％之间时,聚丙烯的结晶速率最快.偏光显微镜的观察揭示出在聚丙烯熔体中原位形成的液晶聚合物微纤诱导了聚丙烯横穿晶的形成.     

液晶共聚物与PSF原位复合的界面研究

合成了两种热致性液晶共聚酯ＢＰ—ＬＣＰ和ＳＤＰ—ＬＣＰ，对其熔融指数、取向性作了考察。选用基体聚砜（ＰＳＦ）与液晶共聚酯进行熔融共混，得原位复合材料。ＳＥＭ断口形态显示了两种液晶在基体中不同的成纤性，并显示出两相的不相容性。采用ＦＴ—ＩＲ方法分析了液晶共聚酯与ＰＳＦ界面间的分子相互作用。进一步研究发现在ＰＳＦ／ＢＰ－ＬＣＰ原位复合体系中加入含ＰＳＦ和ＢＰ－ＬＣＰ的嵌段共聚物，其相容性得以改善     

热塑性树脂的增强：从原位复合材料到原位混杂复合材料

综述了两类增强的热塑性树脂的基本方面。一类是由原位形成的热致液晶聚合物微纤增强的原位复合材料。从实验上研究了获得有效增强效果的两个关键因素；致热液晶聚合物的基体树脂中的成纤，以及在液晶聚合物与基体树脂不相容共混物中的增容作用。另一类是由作者发明的原位混杂复合材料，这一类材料是用直径在两个数量级上的纤维和原位形成的微纤混杂增强的。     

离聚物对含液晶聚合物聚砜体系的增容作用

离聚物对含液晶聚合物聚砜体系的增容作用刘杰，何嘉松（中国科学院化学研究所工程塑料国家重点实验室北京１０００８０）关键词增容作用，离子聚合物，热致液晶聚合物，高分子共混物，原位复合材料工程塑料与液晶聚合物（Ｌｒｙ）共混（形成所谓的原位复合材料）时在降低...     

热致液晶聚合物分散相的形态及其与树脂连续相之间的相互作用

用动态力学谱仪和扫描电子显微镜测试观察了六个含热致液晶聚合物（ＴＬＣＰ）共混体系中的相间相互作用与微结构．组份损耗峰向内或大或小的移动表明在这些共混物中存在着强弱不同的相间相互作用．在各个共混物中所含ＴＬＣＰ公相的形态有圆球状、椭球状、条状和微纤状的．结果表明，在含ＴＬＣＰ的不相容聚合物共混体系中，相间相互作用与微纤形成之间没有直接的相关性．     

热致液晶共聚酯／Nylon－1010共混物的研究

利用偏光显微镜（ＰＬＭ），差示扫描量热计及广角Ｘ－射线衍射等手段研究了热致液晶共聚酯／Ｎｙｌｏｎ－１０１０共混体系．发现当热致液晶共聚酯（ＨＴＨ１０）含量达到３０％时共混物微结构与纯ＨＴＨ１０相似．尼龙－１０１０的结晶度先是随ＨＴＨ１０含量增加而增加，随后又随之下降，但其结晶温度却随ＨＴＨ１０加入而单调下降，共混物的熔融热焓△Ｈｍ在ＨＴＨ１０含量为３０％时与计算值有较大的偏差，广角Ｘ－射线衍射结果表明，此时共混物结构发生了较为明显的变化，两组份之间在此时存在一定的相互作用．     

热致液晶共聚酯／Nylon－1010共混物的研究

 利用偏光显微镜（ＰＬＭ），差示扫描量热计及广角Ｘ－射线衍射等手段研究了热致液晶共聚酯／Ｎｙｌｏｎ－１０１０共混体系．发现当热致液晶共聚酯（ＨＴＨ１０）含量达到３０％时共混物微结构与纯ＨＴＨ１０相似．尼龙－１０１０的结晶度先是随ＨＴＨ１０含量增加而增加，随后又随之下降，但其结晶温度却随ＨＴＨ１０加入而单调下降，共混物的熔融热焓△Ｈｍ在ＨＴＨ１０含量为３０％时与计算值有较大的偏差，广角Ｘ－射线衍射结果表明，此时共混物结构发生了较为明显的变化，两组份之间在此时存在一定的相互作用．     

酸酐化聚砜对聚砜/液晶聚合物共混物的界面增容作用

首先合成了马来酸酐接枝改性聚砜.改性后聚砜材料的表面张力增大,其中的极性分量增加明显,并以此增容聚砜/液晶聚合物(VectraB950)为原位复合体系,研究了增容前后共混物的加工流变行为和界面性能.结果表明,酸酐化聚砜可增强聚砜与液晶聚合物之间的界面作用,引起共混物加工粘度的上升;漫反射FTIR研究表明,增容后共混体系中的特殊相互作用增大;XPS和PLM的研究表明,在熔融加工过程中改性聚砜与液晶聚合物组分之间存在一定的界面化学反应,并生成了接枝共聚物.共混物相容性的提高应归结于相间化学反应与物理作用共同作用的结果.     

MELT BLENDS OF POLY (BUTYLEN TEREPHTHALATE) AND A THERMOTROPIC LIQUID CRYSTALLINE POLYMER

With the help of differential scanning calorimetry, cone-plate and capillary rheometry andscanning electron microscopy, a research has been conducted on rheological behavior,crystallization and morphology of poly (butylene terephthalate) (PBT) blends containing athermotropic LCP. The blend has zero entrance pressure loss, although the LCP has rather largeone. The viscosity curve of the blend lies between those of the LCP and PBT. The crystallizationof PBT is not affected by the presence of the LCP together with no indication oftransesterification between the two ingredients. LCP spheres and ellipsoids with the size of 0. 5--1. 5 μm disperse in PBT matrix uniformly, which is related to the viscosity ratio of the twocomponents.     

Influence of liquid crystalline polymer and recycled PET as minor blending components on rheological behavior,morphology, and thermal properties of thermoplastic blends

In this study, the potential of recycled poly(ethylene terepthalate) (rPET) as a well‐defined reinforcing material for the in situ microfibrillar‐reinforced composite (iMFC) was investigated in comparison with that of liquid crystalline polymer (LCP). Each dispersed phase (LCP or rPET) was melt blended with high density polyethylene (PE) by using extrusion process. The rheological behavior, morphology, and the thermal stability of LCP/PE and rPET/PE blends containing various dispersed phase contents were investigated. All blends and LCP exhibited shear thinning behavior, whereas Newtonian fluid behavior was observed for rPET. The incorporation of LCP or rPET into PE significantly improved the processability. A potential of rPET as a processing lubricant by bringing down the melt viscosity of the blend system was as good as LCP. The elongated LCP domains were clearly observed in as‐extruded strand. Although the viscosity ratio of the rPET/PE system was lower than that of the LCP/PE blend system, most rPET domains appeared as small droplets. An addition of LCP and rPET into the PE matrix improved the thermal resistance significantly in air but not in nitrogen. The obtained results suggested the high potential of rPET as a processing aid and good thermally resistant material similar to LCP. Copyright © 2009 John Wiley & Sons, Ltd.     

热致液晶聚合物的可纺性与其在基体树脂中的成纤

热致液晶聚合物的可纺性与其在基体树脂中的成纤何嘉松，张洪志（中国科学院化学研究所工程塑料国家重点实验室北京１０００８０）关键词热致液晶聚合物，熔融可纺性，高分子共混物，原位复合，亚微米增强用热致液晶聚合物（ＴＬＣＰ）对热塑性树脂产生亚微米级增强作用的...     

酞侧基聚芳醚砜／对苯二甲酸乙二酯－对羟基苯甲酸嵌段共聚物共混物的研究

The blends of phenolphthalein Polyethersulfone (PES - C ) and a thermotropic liquid crystalline polymer (LCP ) were prepared using melting mixing method.Rheological and mechanical properties of the blends were investigated. It was shown that addition of LCP in PES-C resulted in marked reduction of melt viscosity and improved processibility. The Chadly impact strength of the blend containing 2. 5% LCP increased about 2. 5 times comparing with pure PES-C. The tensile strength, Young's modulus, fie-cural strength and flexural modulus of the PES-C/LCP blends were also improved on some extent. The morphology of these blends were also observed by SEM,and the relationship between the me-chanical properties and the morphology of blends were discussed.     

Effect of glass bead packing on the fibrillation of liquid‐crystalline polymer in polycarbonate

Polycarbonate (PC) was melt blended with small amount of liquid‐crystalline polymer (LCP) and various contents of glass beads (GB) having different diameters. The rheological measurements indicated that the GB addition increased the viscosity ratio and seemed unfavorable to the LCP fibrillation. However, the morphological observation showed that the LCP fibrillation was promoted by the GB addition and varied with the GB packing. With the increased GB packing by increasing the GB content and/or decreasing the GB diameter, LCP deformed from spheres and ellipsoids into stretched ellipsoids at lower shear rates and into long fibrils at higher shear rates. Although higher content of smaller GB jammed into the larger LCP droplets and inhibited the LCP fibrillation, very long LCP fibrils formed at higher shear rates at a high enough packing of GB. The relationship between GB packing and LCP fibrillation revealed two kinds of hydrodynamic effects of GB promoting the LCP fibrillation: at lower GB packing, the shear flow was enhanced by the high local shear between GB, in quantity; and for a high enough GB packing, the shear flow was changed, in quality, into elongational flow, which was more effective for the LCP fibrillation. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1020–1030, 2006     

酞侧基聚芳醚砜／对苯二甲酸乙二酯－对羟基苯甲酸嵌段共聚物共混物的研究

酞侧基聚芳醚砜／对苯二甲酸乙二酯－对羟基苯甲酸嵌段共聚物共混物的研究李刚，殷敬华，李滨耀（中国科学院长春应用化学研究所，长春，１３００２２）关键词酞侧基聚芳醚砜，热致性液晶高聚物，原位复合材料，对苯二甲酸乙二酯－对羟基苯甲酸嵌段共聚物将热塑性树脂与热...     

Preparation and properties of self-reinforced polypropylene/liquid crystalline polymer composites

A fast and potentially economic method for creating a composite material of polypropylene (PP) with liquid crystalline polymers (LCPs) was explored. The LCPs were dispersed in the PP matrix in a conventional extrusion process and subsequently drawn in order to obtain a highly uniaxially molecular orientation of the LCP fibres. The strongest mechanical properties were found after rapid cooling of the blend, which was optimally exploited in thin filaments where cooling was fast enough to prevent fibre break-up and/or orientation relaxation. To enable the production of extrudates which are thick enough to be cut into self-reinforced pellets, a fused multi-filament technology was developed. In this technology several thin filaments were extruded/drawn and rapidly cooled to a temperature between the crystallisation temperatures of the LCP and the PP. After solidification of the LCP, the single filaments were fused to a multifilament strand and further cooled to room temperature. The thick multifilament LCP reinforced PP strands were cut into pellets and used in injection-and compression-moulding processes. This processing took place between the melting temperature of the PP and the LCP, with retention of the aspect ratio and the molecular orientation of the LCP fibres.     

PRIMARY STUDY ON BLENDS BASED ON THERMOTROPIC LIQUID CRYSTAL COPOLYESTER AND PET

The blend system composed of PET and thermotropic liquid crystal copolyester based on hydroxy benzoic acid, terephthalic acid, diacetylnaphthalene and PET was studied. The results indicated that LCP could play the role of crystal nuclei. The introduction of LCP decreased the melt viscosity of the system and fibrillous structure could be formed in favor conditions.