新型烯烃嵌段共聚物

来自Dow公司的一种瓶型烯烃嵌段共聚物（OBC）以其独特的嵌段结构突破了烯烃热塑性弹性体的局限。该材料不仅具有优异的可加工性，而且在成本方面能够与TPV TPU和TPE一较高下，在众多应用领域中显示出独特的优势。[编者按]     

揭开烯烃嵌段共聚物的神秘面纱

陶氏化学打破了原有工艺技术的局限性,为制造烯烃嵌段共聚物提供了全新的工艺方法,可实现自由设计,并赋予了烯烃嵌段共聚物独特的性能。[编者按]     

陶氏推出烯烃嵌段共聚物弹性体

英国《欧洲橡胶杂志》2006年188卷4期13页报道： 陶氏化学公司推出一种以嵌段共聚物技术为基础的新型烯烃弹性体。这种烯烃嵌段共聚物（OBC）产品的商品名为Infuse。     

陶氏推出九款开发型烯烃嵌段共聚物

陶氏化学公司近日新推出9款开发型烯烃嵌段共聚物,面市后将作为INFUSE烯烃嵌段共聚物销售。全球客户目前可大批量采购这些开发型烯烃嵌段共聚物,而无需保密协议。     

丁二烯—苯乙烯二嵌段共聚物

以正丁基锂为引发剂 ,环己烷为溶剂 ,THF,2G,TMEDA为极性调节剂 ,合成了丁二烯 -苯乙烯二元共聚物。结果表明,和普通溶聚丁苯橡胶相比 ,该共聚物不仅具有良好的物理机械性能 ,同时具有低滚动阻力和高抗湿滑性能     

用于烯烃嵌段共聚物生产的催化剂

三井化学公司和道化学公司就联合开发用于烯烃嵌段共聚物（OBCs）生产的催化剂体系达成协议，通过主动交换单中心催化技术资料，加速该新型功能聚合物的开发和产生。这是三井化学公司首次与海外公司在高性能树脂方面进行联合开发，该公司计划最早在2007年使该催化剂体系工业化。     

烯烃多嵌段共聚物的结构、合成及应用

烯烃多嵌段共聚物是一种新型的聚烯烃热塑性弹性体,主要通过催化乙烯和1-辛烯链穿梭聚合制备得到多嵌段含"软段"和"硬段"的聚合物,其独特结构和性能已经成为新材料的研究热点.本文概述了烯烃嵌段多共聚物的结构和制备合成,并指出了烯烃多嵌段共聚物性能和应用前景.     

新型烯烃嵌段共聚物

<正>据www.ptonline.com报道,陶氏化学(美国密歇根州米德兰)有限公司,推出了高相对分子质量烯烃嵌段共聚物新牌号产品,用于吹塑薄膜。据说新产品具有好的拉伸和弹性性能,作为菱形花型织物的组分用,如用于成型耳机和腰带。嵌段共聚物制备的耳机、腰带和女子体操服的侧面料为弹性层压材料,能给消费者提供喜欢的弹性和柔软度。     

SBS嵌段共聚物的结构,性能及应用

ＳＢＳ嵌段共聚物的结构、性能及应用孙小青译在过去十几年中，含３０％的聚丁二烯的苯乙烯－丁二烯（ＳＢ）共聚物在透明和抗冲击材料领域中占有一席之地。以其韧性、高品质、结晶透明性主要用于食品餐饮的发泡包装、自助冷饮杯、透明薄膜、套管、铰链式包装、冰箱外壳和...     

Fractionation and Analysis of an Impact Poly(propylene) Copolymer by TREF and SEC‐FTIR

TREF fractionation was combined with SEC‐FTIR analysis to measure the compositional heterogeneity within a commercial impact PP copolymer. The chemical composition of all fractions was determined as function of their molecular weight distribution. This approach proved to be highly successful at identifying different constituents within fractions exhibiting bimodal molecular weight distributions. Furthermore, the determination of ethylene and propylene crystallinity distribution across the molecular weight distribution confirmed the morphological nature of each of the components of the bimodal distribution. It is demonstrated that the combination of TREF and SEC‐FTIR provides a simple alternative to more time‐consuming conventional ways of characterising impact PP copolymers of complex heterogeneity.

     

聚酰胺6—聚醚嵌段共聚物增韧改性

以聚四氢呋喃醚为软段制备大分子活化剂,引发己内酰胺阴离子聚合,合成了聚酰胺６－聚醚嵌段共聚物,并考察大分子活化剂种类、用量对聚合物力学性能的影响。结果表明,所得制品在保持一定强度、硬度的条件下,冲击性能可大幅度提高,取的了较好的增韧效果。     

PEP聚醚型非离子表面活性剂的合成与性能研究

本文以聚乙二醇和环氧丙烷为原料,用常压法合成了一系列“氧化丙烯－氧化乙烯－氯丙烯”嵌段共聚醚,对 进行了结构表征,对反应影响因素了探讨,并对产物的表面活性性能进行了测定研究。     

Studies of the comonomer distributions in low density polyethylenes using temperature rising elution fractionation and stepwise crystallization by DSC

The comonomer distributions of commercial linear low density polyethylenes (LLDPE) and linear very low density polyethylenes (VLDPE) produced with traditional high activity Ziegler–Natta (Z–N) catalysts were characterized by temperature rising elution fractionation (TREF). In order to develop faster characterization methods the polymers were also characterized using a segregation fractionation technique (SFT) based on a stepwise crystallization by differential scanning calorimetry (DSC). Comparative studies of SFT and TREF demonstrated that SFT provides an alternative tool for the relative qualitative analysis of the chemical composition distribution (CCD) and the technique is useful to characterize the heterogeneity in comonomer unit distribution. Lamellar thickness distributions can be calculated from the DSC endo-therms by applying the Thomson–Gibbs equation. The SFT technique was also applied to commercial single-site (metaliocene) LLDPE and VLDPE polymers. In spite of their more homogeneous structure compared with the Z–N copolymers, which contain many active sites, these single site copolymers also gave thermograms resolved into several peaks.     

Studies of thermal oxidative degradation of polypropylene impact copolymer using the temperature rising elution fractionation method

Thermal oxidative degradation of polypropylene impact copolymer has been studied with its fractions obtained using the temperature rising elution fractionation method. The fractions were analyzed using ¹³C NMR, Fourier transform infrared and differential scanning calorimetry measurements, and the chemical structure, isotacticity, conformation and melting point were investigated. It is found that these fractions are composed of a homopolymer or a polymer blend of polypropylene, polyethylene and ethylene–propylene copolymer. The thermal oxidative degradation of each fraction was carried out at 130 °C, and the degradation progress was estimated by the change of molecular weight distribution (from gel permeation chromatography curves). The rate of degradation is found to be dominated by the content of tertiary C? H bonds (propylene unit) and the existence of 3₁ helix conformation corresponding to a crystalline polypropylene part in each fraction. The latter is more evident leading to the degradation reaction path with a lower activation energy. Copyright © 2007 Society of Chemical Industry     

SBS/SIS嵌段共聚物的有机硅改性研究

嵌段共聚物SBS／SIS由于结构中有不饱和键而存在耐热、耐老化性较差的问题,采用不同单体和有机硅对嵌段共聚物进行复合改性,并通过测试所制胶黏剂的软化点、剥离强度、硬度、接枝率和黏度等各项指标评价其改性效果。由于加入WD-20改性后生成具有Si—O键的SBS／SIS聚合物,对所连烃基起屏蔽作用。提高了胶的热氧化稳定性。同时生成交联度更加稳定的Si-O-Si键可防止主链的断裂降解。从而使胶的耐热性能有所提高。实验结果证实了对嵌段共聚物SBS／SIS进行有机硅复合改性后,其耐热、耐老化性能得到明显提高,从而拓宽了其使用范围。     

Synergistic Effect of Halloysite Nanotubes and MA-g-PE on Thermo-Mechanical Properties of Polycarbonate-Cyclic Olefin Copolymer Based Nanocomposite

This article explores the synergistic effect of halloysite nanotubes along with maleic anhydride grafted polyethylene on the physical, mechanical, and thermo-mechanical properties of polycarbonate/cyclic olefin copolymer polymer blend system. Halloysite nanotubes filled polycarbonate/cyclic olefin copolymer blend nanocomposites were prepared in the presence and absence of polymeric compatibilizer by melt blending. Besides the constructive outcome of nanotubular fillers, the maleic anhydride grafted polyethylene played a complementary role in improving the properties of the nanocomposites. Structural changes of blend matrix, nanofiller distributions, nanofiller-polymer matrix interaction, nucleating effect, storage modulus, and thermal stability were widely investigated with various sophisticated instruments.     

Effect of Graphitic Nanosheets on the Physical Properties of Cyclic Olefin Copolymer Composite Films

In this study, microstructural and physical properties of cyclic olefin copolymer composite films prepared by melt processing method and using of graphitic nanofillers, namely, graphite, graphite oxide, and reduced graphite oxide were investigated. Structural and physical properties of the chemically modified graphites and composite films were characterized by the Fourier transform infrared, X-ray diffractometer, scanning electron microscopy, dynamic mechanical analyzer, and thermogravimetric analyzer methods. It was found that the composite films including reduced graphite oxide exhibited exfoliated structure whereas graphite- and graphite oxide-based films showed intercalated structure. It was also obtained that all composite films showed superior gas barrier performance compared to the cyclic olefin copolymer.     

升温淋洗分级研究聚丙烯流延膜专用料的微观结构及热学表征

采用升温淋洗分级技术分离了2种聚丙烯流延膜(CPP)专用料(CPP1、CPP2),通过红外光谱仪、差示扫描量热仪和高温凝胶色谱对2种样品的链结构、熔融和结晶行为进行了表征,确定了产品各级分的分子结构信息.结果表明,对于低温(<100℃)级分,CPP1样品中其含量为9.29％(质量分数,下同),CPP2样品中其含量为26...     

Carbon‐13 NMR,GPC, and DSC study on a propylene‐1‐butene copolymer fractionated by temperature rising elution fractionation

A random copolymer of propylene with small amounts of 1‐butene comonomer, synthesized with a Ziegler–Natta catalyst, was fractionated by temperature rising elution fractionation (TREF) to systemically investigate the fraction samples' molecular microstructure, as well as their relationship to the melting and crystallization behavior. First, TREF was employed to fractionate the sample, and then crystallization analysis fractionation (Crystaf) was used to check the effect of the TREF experiment. In the characterization of the molecular microstructure, carbon‐13 NMR spectroscopy (¹³C NMR) and gel permeation chromatography (GPC) experiments gave the following results: the fraction samples have relatively uniform molecular microstructure; with an increase in elution temperature, the 1‐butene content in the fraction samples decreases, but the molecular weight (M_n) and number average sequence length of propylene (n?_P) increase. In the study on melting and crystallization behavior, differential scanning calorimetry (DSC) experimental results show that the melting temperature increasingly decreases with an increase in 1‐butene content; however, dependence of the melting temperature on molecular weight becomes weaker and weaker with an increase in the number average molecular weight in the range of number average molecular weight below 1.82 × 10⁵ g/mol. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 845–851, 2006