高不饱和丁基橡胶的合成与制备技术研究进展

Research Progress and Perspectives of in Synthesis and Preparation Technology of High Unsaturated Butyl Rubber

传统丁基橡胶(IIR)是由异丁烯和异戊二烯在低温下共聚而成,具有良好的化学稳定性、热稳定性和优异的气密性,主要用于轮胎内胎和无内胎轮胎的气密层。提高丁基橡胶的不饱和度有助于提高其硫化效率,并改善与其他种类弹性体的粘接性能,拓宽丁基橡胶的应用范围。本文对具有一定不饱和度的丁基橡胶的合成技术研究进展进行了综述,系统介绍了由Lewis酸和有机卤化物组成的引发体系、由茂金属或有机金属及衍生正离子源与弱配位负离子组成的引发体系、铝的烷基卤化物引发体系以及烷基锌氯化物引发体系引发异丁烯-不饱和烯烃的聚合,对各体系的异同进行了深入的分析和阐释,对高不饱和丁基橡胶的设计、开发和研究工作起到了理论指导和思路借鉴作用,并对该领域未来的发展进行了展望。

Butyl rubber, also known as isobutylene-isoprene rubber(IIR), is a synthetic elastomer produced by cationic copolymerization of isobutylene with around 0.6 to 2.5 percent isoprene in chlorocarbon solvents at low temperature. Butyl rubber has unique elastomeric properties that makes it a good choice for a wide variety of rubber goods. Its excellent impermeability to gas diffusion together with its flexibility makes it the ideal material for inner tubes of tires and other high-pressure tubes. The isoprene provides the necessary unsaturation sites for crosslinking. Thus, improving the degree of unsaturation(Du%) of butyl rubber can enhance the vulcanization efficiency, and the bonding property between the butyl rubber and other kinds of rubber is improved, which will broaden the application of butyl rubber. In this review, we provide an overview of the research progress of the synthesis and preparation of high unsaturated butyl rubber. Four kinds of initiators, for instance, Lewis acids and organic halides, coordination complex consisting of cationic source derived from metallocene or organometallics and weak coordinate anions, alkyl halides of aluminum and chlorides of zinc alkyls, are summarized and elaborated in this review. Moreover, we prospect the development of high unsaturated butyl rubber. This review will undoubtedly act as a great reference and theoretical guidance for researchers engaged in synthesizing and preparing high unsaturated butyl rubber.