工程塑料近二十年进展

叙述了通用工程塑料、特种工程塑料、聚烯烃复合材料及合金和ABS过去二十年进展,重点讨论了工程塑料单体新技术及新单体/新聚合物、聚合物增韧核——壳结构理论、纳米复合材料、反应器合金、长纤维增强热塑性塑料(LFT)、工程塑料回收及产业动态。     

人物介绍

基本情况 化学所从事工程塑料及其相关领域的研究始于20世纪80年代,1991年利用世界银行贷款“重点学科发展项目”开始实施“工程塑料国家重点实验室”建设项目,1993年获准边建设边开放,1995年作为工程塑料国家重点实验室通过国家验收,漆宗能任室主任(1992～1997).1999年整合烯烃聚合、耐高温芳杂环等高分子化学部分研究组,整体进入中国科学院知识创新工程的重要组成部分——北京物质科学基地分子科学中心.2003年北京分子科学国家实验室筹建,工程塑料室纳入国家实验室管理,2004年验收为中国科学院工程塑料重点实验室.实验室主任分别为:何嘉松(1997～2003)、王笃金(2004～2014)、阳明书(2015～现在).     

热致液晶高分子与聚碳酸酯原位复合材料的研究

<正> 热致液晶高分子(TLCP)是一种具有高强度、高模量和良好加工性能的新型高分子材料,在流场、温度场和应力场的作用下,易于取向,产生自增强效果.与工程塑料原位(insitu)复合,可以改善工程塑料的流变性能和加工性能,同时还可以提高工程塑料的力学     

中国科学院化学研究所工程塑料国家重点实验室简介

中国科学院化学研究所工程塑料国家重点实验室简介何嘉松（中国科学院化学研究所工程塑料国家重点实验室，北京，１０００８０）中国科学院化学研究所工程塑料国家重点实验室是世界银行贷款“重点学科发展项目”子项目之一，于１９８９年进入实质性的可行性研究阶段，经过...     

超临界甲醇降解对苯二甲酸丁二酯的研究

作为一种综合性能优良的新型工程塑料,对苯二甲酸丁二酯(PBT)工程塑料及其各种合金在全球范围内已经广泛用于电子电气、汽车、机械及民用等各个领域,而中国是其中需求量最大的国家．     

工程塑料实验室发展历程及展望

正基本情况化学所从事工程塑料及其相关领域的研究始于20世纪80年代,1991年利用世界银行贷款"重点学科发展项目"开始实施"工程塑料国家重点实验室"建设项目,1993年获准边建设边开放,1995年作为工程塑料国家重点实验室通过国家验收,漆宗能任室主任(1992~1997)。1999年整合烯烃聚合、耐高温芳杂环等高分子化学部分研究组,整体进入中国科学院知识创新工程的重要组成部分——北京物质科学基     

读者·作者·编者

欢迎订阅《化学分析计量》、《工程塑料应用》及合订本光盘邮发代号24-138,24-42全国各地邮局均可订阅也可直接通过邮局或银行汇款向《化学分析计量》杂志社订阅《化学分析计量》、《工程塑料应用》及合订本光盘,请注明订阅期刊/光盘的名称、收件人、邮编及地址。     

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...     

漆宗能先生简介

正漆宗能先生(1934~2016)是重庆江津人,我国著名高分子科学家。他曾任原工程塑料国家重点实验室和工程塑料国家工程中心主任,国家高技术新材料"863"专家委员会委员,国家自然科学基金委学科组长,中国化学会理事,中国材料研究学会理事,并享受政府特殊津贴。     

上海杰事杰新材料(集团)股份有限公司

正国家创新型试点企业——上海杰事杰新材料(集团)股份有限公司是由中国十大杰出青年杨桂生博士创办、依托于中国科学院化学研究所的国家级高新技术企业,是中国工程塑料和复合材料领军企业,是近年来党和国家领导人重点关注、主流媒体重点报道的自主创新和节能减排先进典型之一。自1992年创立之日起,公司就一直致力于工程塑料等高分子材料的研究、开发、产业化,目前拥有的     

POLYMERS BEYOND THE YEAR 2000

At the turn of the century, the global polymer industry is undergoing the most rapid and dramatic changes in itshistory. Emerging markets, particularly in Asia, and their polymer consumption are catching up with other parts of the world,creating new business opportunities. Economy of scale, combined with optimized logistic concepts, is becoming a keyeconomic success factor, thus forcing smaller suppliers out of business and creating a major hurdle for newcomers and theintroduction of new products. Globalization of polymer customers and cost pressure lead to a consolidation of suppliers andproducts. Today standard thermoplastics have a dominant position in the market and they will retain this position in future.Engineering thermoplastics are facing growing competition due to the increased efficiency of standard polymers. This leadsto a displacement process where standard polymers substitute engineering thermoplastics. Simultaneously engineeringpolymers are pushing into new markets or applications or displacing materials like glass, wood or metal. The recent historyand future trends have a strong impact on R&D activity in the polymer industry. Competition on a global scale andincreasing cost pressure are turning innovation into an essential precondition of commercial success, thus determining theobjectives of industrial polymer research and development.     

Effects of irradiation conditions on the weathering of engineering thermoplastics

The nature of the light source and its intensity can be important variables in accelerated weathering of aromatic engineering thermoplastics. Activation spectra show that BPA polycarbonate (PC) and its blends are very sensitive to UV with wavelengths <300 nm, as is well-known in the literature, but other resins gave unremarkable results. Xenon arc weathering experiments performed under identical conditions, but with different filter combinations did not show consistent rate enhancements. For 48 samples across a range of aromatic engineering thermoplastics, conditions using borosilicate inner and outer filters were 1.7× harsher than the CIRA/soda lime filter combination. However, the range was 1.0-2.5 and the standard deviation was approximately 0.35 making the correlation 1.7 ± 0.7 at 95% confidence level for any given sample. The quartz/borosilicate combination used in SAE J1960 was 2.3× harsher than CIRA/soda lime conditions, but the standard deviation was 1.1 making the correlation 2.3 ± 2.2 at the 95% confidence level for any given sample. The effects of irradiance level and the dark cycle were determined in order to establish the legitimacy of accelerated testing methods. Linear increases in degradation with increased irradiance were observed for PC, poly(butylene terephthalate), and blends of PC with other polymers. Some non-linearity was found for styrene acrylonitrile copolymer (SAN), and extreme non-linearity was found for ABS. No effect was found from a light/dark cycle other than the rate reductions expected from the lower dose rate. Thus, for accelerated weathering of engineering thermoplastics, the best possible match for sunlight is required, but increasing the intensity and decreasing or eliminating the dark period are permissible for most aromatic thermoplastic resins.     

History of Engineering Thermoplastics

When engineers design high-performance precision products made from plastics, they demand that the plastic materials should approach or even surpass conventional structural materials, particularly in areas such as modulus, strength, creep resistance, lubricity, thermal expansion, high-temperature properties, heat aging, and high-frequency dielectric loss. In response to these demands, polymer chemists have developed a series of high-performance “engineering” thermoplastics offering a wide variety of choice in balance of important engineering properties. These include the fluoroplastics, aliphatic and aromatic polyethers, polyacetals, polysulfones, aromatic polyesters, and aliphatic and aromatic polyamides.     

Effects of temperature on the weathering of engineering thermoplastics

We have determined the activation energies (E_a) of yellowing and gloss loss for a large number of engineering thermoplastics and blends under accelerated weathering conditions. The E_a often depend on the property measured and exposure conditions, although they vary over a fairly small range. Under the CIRA/sodalime-filtered xenon arc conditions most likely to be representative of outdoor exposure, the E_a for gloss loss was ≤5 kcal/mol for all samples tested. The E_a for yellowing was also ≤5 kcal/mol except for SAN and ABS. Evidently the color bodies formed from photo-oxidation of SAN are more sensitive to temperature. A reaction with an E_a of 5 kcal/mol will increase its rate by about 33% for each 10 °C increase in temperature near room temperature. Temperature is an important, but not overwhelming, variable in the weathering of most engineering thermoplastics.     

Reproducibility of Florida weathering data

We have investigated the consistency and reproducibility of Florida outdoor weathering data for aromatic engineering thermoplastics. Weather and broadband (295–385 nm) UV dose data for the 14-year period from 1989 to 2002 show that considerable variability is expected for exposures with duration < 1 year, but that standard deviations for UV exposure and temperature are approximately 7% of the mean at 1 year and <5% at 2 years and greater. Only rainfall shows significant long-term variability. Weathering data on pigmented aromatic engineering thermoplastics were consistent with these expectations. Overall trends and rates of color and gloss shifts were generally reproduced for samples exposed at different times. Color shift data were generally reproducible within a ΔE of 2 and 60° gloss loss within 10 units for samples beginning exposure 6 months apart. However, very large differences in absolute values for properties can occur for data taken near periods of rapid change, especially for gloss loss. Surprisingly, considering the data as a function of broadband UV dose rather than exposure time did not seem to reduce scatter. This emphasizes the problem of comparing results between data sets for exposure times < 1 year. We conclude that Florida data do provide a useful benchmark when rates and general trends are compared, but not for absolute values at arbitrary times.     

Regioselective C−H Xanthylation as a Platform for Polyolefin Functionalization

Polyolefins that contain polar functional groups are important materials for next‐generation lightweight engineering thermoplastics. Post‐polymerization modification is an ideal method for the incorporation of polar groups into branched polyolefins; however, it typically results in chain scission events, which have deleterious effects on polymer properties. Herein, we report a metal‐free method for radical‐mediated C?H xanthylation that results in the regioselective functionalization of branched polyolefins without coincident polymer‐chain scission. This method enables a tunable degree of polymer functionalization and capitalizes on the versatility of the xanthate functional group to unlock a wide variety of C?H transformations previously inaccessible on branched polyolefins.     

聚乙烯吡咯烷酮聚合物复合膜的制备及其性能研究——推荐一个研究型综合实验

A research-based comprehensive experiment was introduced: preparation and investigation of polyvinylpyrrolidone (PVP) blend membranes in which PVP was employed as the membrane matrix. Three kinds of engineering thermoplastics were chosen to enhance the dimensional and mechanical stabilities of PVP based membranes. The physicochemical properties were investigated. This experiment relates to physical chemistry, polymer chemistry, organic chemistry, electrochemistry and instrumental analysis. It covers polymer blending, membrane fabrication by solution casting, characterization and performance test. Through this experiment, students can get knowledge of fabrication and characterization methods for polymer electrolyte membrane, which arouses students' interest in scientific research, cultivates students' innovative ability, fosters students' practical skills and promotes their integrative skills of applying knowledge.     

Progress in the chemistry of functional aramids properties

High-performance polymers based on amide aromatic rings are known as wholly aromatic polyamides or aramids. The arrangement and admirable properties of aramids are built on the basis of amide linkage and rigid aromaticity. Aramids are attractive because of their extraordinary bond strengths and very high stiffness. Synthetic aromatic polymeric chains provide increased mechanical resistance and thermal softening compared to aliphatic aramids. In addition, aramids exhibit high thermal stability, low creep, and good optical activity with fluorescence. Hence, aramids are found in advanced arenas for engineering thermoplastics such as transport applications, electroactive materials, films, bullet-proof body armor, smart materials, protective clothing, fibers, in nanocomposites as asbestos alternatives, cutting edge complexes in arming, high-temperature lining material, in space engineering, and more. The objective of this review is to make the field of aramids functionality more accessible to the materials science community, that is, scientists, academicians, and engineers.     

Study of the toughening mechanism of crazing in rubber modified thermoplastics

Single crazes in transparent glassy thermoplastics are measured by means of optical interferometry. Applying numerical or analytical methods to measured creaze shapes, also their micromechanics has been evaluated. These data can be transferred to rubber-modified species of the respective thermoplastics to predict craze-governed toughening. Such predictions can be verified by comparison with results of electron microscopic investigations.Dedicated to Professor Hans-Henning Kausch on the occasion of his 60th birthday.