2001年《弹性体》征订启事

《弹性体》是国内外公开发行的中央级弹性体行业技术性期刊 ,中国期刊网全文收录期刊 ,已被CA、EI、SCI等国际学术界公认的权威检索期刊收载。由中国石油天然气总公司主管 ,全国合成橡胶信息总站主办 ,中油吉林石化公司研究院出版 ,国内外公开发行。本刊以理论性、实用性与信息性为特色 ,主要报导合成橡胶 (通用胶和特种胶 )、胶乳、天然橡胶及其改性、塑料橡胶共混改性与高分子合金材料的科研、生产和加工应用技术。刊登有关弹性体工业的技术开发、技术改造、技术进展、技术经济评价等方面的专论、综述、预测 ,以及讲座、外商技术座谈和…     

聚氯乙烯／热塑性弹性体共混增韧的研究进展

聚氯乙烯（PVC）是一种性能优良,价格低廉的通用树脂,但其脆性大、热稳定性差、加工性能不佳等,需要进行改性。通过用热塑性弹性体（TPE）对PVC进行共混增韧改性,可得到高性能的PVC复合材料。共混改性为PVC增韧改性的最简单易行的有效方法。本文概述了聚氯乙烯／热塑性弹性体共混体系的种类和制备方法,同时对影响热塑性弹性体...     

胶粉的改性及其在热塑性弹性体中的应用

我国每年产生大量的废橡胶造成了严重的环境污染,作为废橡胶回收再利用的有效途径,胶粉的研究和应用受到广泛关注.本文介绍了胶粉的脱硫再生改性技术与表面活化改性技术及胶粉在热塑性弹性体中的应用,简述了胶粉基热塑弹性体的制备方法并比较了熔融共混法与动态硫化法的区别,概述了各类胶粉基热塑性弹性体的研究现状,着重介绍了胶粉基热塑弹...     

三元乙丙橡胶/聚丙烯热塑性弹性体

综述了三元乙丙橡胶/聚丙烯(EPDM/PP)热塑性弹性体的发展历程、市场情况以及EPDM/PP热塑性弹性体的结构、性能及其影响因素。EPDM/PP热塑性弹性体由EPDM和PP通过动态硫化技术制备而成,在室温下具有橡胶的高弹性,在加工温度下具有塑料的流动性。在性能上,EPDM/PP热塑性弹性体受加工设备、共混工艺、配合体系的综合影响。     

中国高分子工业技术进展

介绍了“十五”期间国内合成树脂、合成纤维、合成橡胶等高分子材料生产技术的新进展.聚合工艺技术开发方面,大型化的聚丙烯、聚乙烯、聚酯、顺丁橡胶、SBS热塑性弹性体、溶聚丁苯橡胶、丁基橡胶等高分子聚合成套工艺技术相继开发成功,建成了国产化的生产装置.纺丝成套工艺技术开发方面,大容量涤纶短纤、腈纶生产技术亦取得重要进展.合成材料新产品开发方面,合成树脂专用料比例、合成纤维差别化率和合成橡胶新产品比例均有了明显提高.化工新材料方面,在非通用合成树脂,如增粘PET、环氧树脂、聚氨脂,工程塑料,如尼龙6、PBT,以及高性能纤维,如超高分子量聚乙烯纤维、PBO纤维的合成工艺技术开发与新产品开发方面均取得了重要的进展.     

晶须及其在高分子材料中的应用

简要介绍了目前高分子材料改性中常用的晶须，如钛酸钾晶须、硼酸铝晶须、氧化锌晶须等，主要对其在橡胶、热塑性弹性体、热塑性树脂以及热固性树脂中的应用作了详尽论述。     

核－壳型弹性体对热塑性树脂的增韧

本文阐述了橡胶微粒对热塑性树脂的增韧机理，以及核－壳弹性体对塑料共混物性能的影响。其目的是为合成抗冲改性用核－壳弹性体提供参考。     

纳米SiO2增强NR/HDPE共混型热塑性弹性体的研究

以动态硫化法制备纳米二氧化硅(SiO2)改性天然橡胶／高密度聚乙烯(NR／HDPE)共混型热塑性弹性体。研究了纳米SiO2对NR／HDPE弹性体力学、耐热变形、耐溶剂和热塑性能的影响，并用SEM分析了弹性体的断面形貌。结果表明：纳米SiO2通过细化交联NR分散相，改善了NR与HDPE的相容性，两相界面粘结强度明显提高。当纳米SiO2质量分数为0．03时，NR／HDPE弹性体的综合性能最好。     

分子设计在热塑性弹性体制备中的应用

本文综述了近年来基于分子设计原理制备的热塑性弹性体的研究报道,包括提高聚氨酯热塑性弹性热稳定性和柔韧性;用立构可控茂金属催化剂制备聚丙烯热塑性弹性体;热可逆共价交联聚合物和星型结构、棕榈树结构、哑铃形结构聚合物的研究.同时对乳液互穿网络型热塑性弹性体以及热塑性弹性体共混物进行了简要介绍.     

热固性树脂韧性的改进途径及其增韧机理

本文系统地综述了加入无机填料、弹性体及热塑性塑料;与热塑性塑料形成半IPN(Semi-Interpenetruting Polymer Network);改变交联网的化学结构;控制分子交联状态的不均匀性等增加热固性树脂韧性的途径。并对以上几种增韧途径的机理及其橡胶改性体系相分离的热力学和动力学判据也进行了讨论。     

Fourier transform raman spectroscopy of elastomers: An overview

The application of FF Raman spectroscopy in the field of elastomers has been reviewed. FT Raman spectra of various natural and synthetic elastomers are presented to illustrate both the advantages and the limitations of the technique.Carbon black and some oils, when compounded with natural and synthetic elastomers, prevent the acquisition of useful Raman spectra. However, all other commercial samples studied produced excellent spectra in the raw and vulcanized states without any sample pre-treatment.This has allowed quantitative work on blends and isomeric elastomers and also the direct study of the rubber vulcanization process.Future developments of the technique are discussed.     

Mechanistic Investigations of Surface Modification of Carbon Black and Silica by Plasma Polymerisation

Carbon black is widely used as an active filler in the rubber industry to improve the physical properties of rubber. The surface energy of carbon black is high compared to that of various elastomers like styrene–butadiene rubber (SBR), butadiene rubber (BR) and ethylene–propylene–diene rubber (EPDM). The work aims at reducing the surface energy of carbon black by modifying its surface for application especially in rubber blends. The present paper looks into the possibility of using plasma polymerisation of acetylene as a surface modification technique for carbon black in comparison with silica. Thermogravimetric analysis, wetting behaviour with various liquids of known surface tension and time of flight secondary ion mass spectrometry (ToF-SIMS) were used to characterise the carbon black before and after surface modification. The study shows that surface modification of carbon black by plasma polymerisation is difficult in comparison with silica, unless treated for long duration. The mechanistic aspects of the surface modification and the importance of active sites on the carbon black surface for effective modification are discussed in the paper.     

弹性体拉伸取向和应变诱导结晶研究进展

橡胶拉伸取向和应变诱导结晶被公认为是天然橡胶和一些合成橡胶(如氯丁橡胶、丁基橡胶、氢化丁腈橡胶等)高效自增强的关键所在,研究该现象和行为规律对理解橡胶增强机理具有十分重要的意义.本文总结了常用于研究橡胶拉伸取向和应变诱导结晶的表征方法,对其原理、特点和适用范围进行了对比分析;综述了纳米填料(炭黑,二氧化硅,黏土,碳纳米...     

Das elastische Jahrhundert. Synthesekautschuke

Synthetic rubbers help to solve severe problems in rubber‐technology arising from the sensitivity natural rubber shows towards UV‐radiation (e.g. sunlight), heat, and ozone: For this reason more than half of the rubber demand nowadays is satisfied by the chemical industry. However, synthetic rubbers are superior to its natural counterpart not only in regard to their ageing resistance and robustness towards several chemicals: They can easily be adapted to new challenges born by a more and more demanding technology – e.g. using improved concepts in the design of rubber molecule architectures, new catalysts or post‐polymerization altering of the elastomers. These challenges demand for a deep and clear understanding of rubber's chemistry and physics.     

Structural and mechanical study of elastomers under plane deformation

The plane shrinkage of various elastomers [natural rubber, synthetic isoprene rubber, and plasticized poly(vinyl chloride)] at room temperature has been studied via direct microscopic observations. Prior to deformation, the surface of polymer samples is decorated with a thin (several nanometers) metallic layer. Further deformation leads to formation of the surface relief in the coating. An analysis of the formed microreliefs allows one to visualize and characterize the induced stress field in the sample. The shrinkage of poly(vinyl chloride) samples is accompanied by development of the uniform surface relief over the whole surface of the deformed polymer. This fact suggests a homogeneous character of the stress field and, hence, a homogeneous structure of the polymer sample. In the case of crosslinked rubbers (natural rubber and synthetic isoprene rubber), their plane shrinkage leads to the development of an irregular pattern on the polymer surface. In addition to the folded surface relief that is typical of the poly(vinyl chloride) structure, one can observe 20-to 50-μm “islands,” which are characterized by their own morphological features. Information on structural inhomogeneity of rubbers that is obtained by scanning electron microscopy correlates with the data of DSC measurements. The advantages of electron microscopic procedure for studying structural rearrangements in polymers during strain recovery of elastomers are demonstrated.     

Study on mechanical properties of elastomers reinforced by zinc dimethacrylate

In this work, mechanical properties of various elastomers with the representative structural features reinforced by zinc dimethacrylate (ZDMA) were studied. The results showed that there is great difference in reinforcing effects of ZDMA for different elastomers. Strain-stress curves revealed that the tensile-induced crystallization of chains might be the main reason for high strength of ZDMA/rubber composites at room temperature. The saturation and regularity of rubber chains are two essential features to determine the mechanical properties of the composites at room temperature. The kind of ZDMA makes considerable impact on performances of ZDMA/rubber composites, except for ZDMA/hydrogenated nitrile-butadiene rubber (HNBR) composite. The high temperature strengths of ZDMA/rubber composites are not high and are dominated by the polarity and saturation of matrix. Basing on the previous researching, a possible model for microstructure of ZDMA/rubber composites was put forward, which could well interpret the observed phenomenon.     

A chemical modification approach for improving the oil resistance of ethylene-propylene copolymers

The need for a low-cost and weather, high-temperature and oil-resistant rubber is well-established in the market place. Such products have the potential to replace high cost rubbers and/or oil-resistant rubbers that lack weather and high-temperature resistance. The present study aims at increasing the polarity of EP(D)M rubber by chemical modification and cross-linking of EPM copolymer grafted with maleic anhydride (EPM-g-MA). First, it is shown that the oil resistance of rubbers can be predicted using calculated solubility parameters. Next, a variety of modified EPMs has been designed, directed at a high polarity in combination with a relatively low glass transition temperature, and have subsequently been prepared to validate the concepts experimentally. The various modification approaches resulted in (significantly) improved oil resistance and are in fair agreement with the calculated oil swell data. It is concluded that new rubber materials based on EPM-g-MA can be developed, that may replace existing oil-resistant elastomers.     

NATURAL RUBBER LATEX PRODUCTS: CONCERNS IN HEALTH CARE

ABSTRACT

In the last decade, there has been a tremendous increase in the reports on adverse allergic reactions from natural rubber latex products used in the health care field. One of the reasons for the widely reported latex allergy is attributed to the increased use of natural rubber latex products, mainly gloves, since the emergence of deadly diseases such as Acquired Immunodeficiency Syndrome (AIDS), hepatitis, etc. This review presents the latest reported clinical manifestations from contact with natural rubber latex products, at the same time exploring the reasons behind these allergies, which are mainly attributed to the protein and rubber additives present in these latex products. The wish for better safety and health has led to the rise of synthetic rubber as an alternative to natural rubber products, the only advantage being the absence of proteins in them, while the toxicity from the chemicals remains the same. The synthetic elastomers, along with other alternatives like radiation and peroxide prevulcanized latices, hydrophilic coatings, glove liners, etc., are also dealt with in detail. The review also discusses the diagnostic methods available for latex allergy, methods of protein determination, organizations dealing with latex allergy, FDA ruling on gloves, etc.     

液晶弹性体刺激形变研究

开发可以通过外部刺激产生机械形变的人工致动材料是一个近年来的研究热点。其中,液晶弹性体因结合了聚合物网络的橡胶弹性和液晶的有序性而具有独特的性质,在热、光、电等的外界刺激下可以产生可逆的形状记忆效应。本文综述了液晶弹性体响应多种外界刺激产生各种形变的行为,主要介绍了有关热致形变液晶弹性体、电致形变液晶弹性体、化学刺激导致形变的液晶弹性体及光致形变液晶弹性体的研究进展,阐述了各类液晶弹性体产生形变的机理包括热致、电致和光致相转变,讨论了影响其响应性能的主要因素,并展望了这一领域的发展前景。     

Independent Control of Elastomer Properties through Stereocontrolled Synthesis

In most synthetic elastomers, changing the physical properties by monomer choice also results in a change to the crystallinity of the material, which manifests through alteration of its mechanical performance. Using organocatalyzed stereospecific additions of thiols to activated alkynes, high‐molar‐mass elastomers were isolated via step‐growth polymerization. The resulting controllable double‐bond stereochemistry defines the crystallinity and the concomitant mechanical properties as well as enabling the synthesis of materials that retain their excellent mechanical properties through changing monomer composition. Using this approach to elastomer synthesis, further end group modification and toughening through vulcanization strategies are also possible. The organocatalytic control of stereochemistry opens the realm to a new and easily scalable class of elastomers that will have unique chemical handles for functionalization and post synthetic processing.