异丁烯系共聚物的最新进展

本文简要介绍了异丁烯系共聚物的最新进展，对星形支化丁基橡胶，异丁类－对甲基苯乙烯共聚物及其溴化共聚物以及溴化丁基橡胶的改性等的合成，性能和应用进行了分析讨论，并提出加速研制生产丁基橡胶等的意见。     

Green strength enhancement in BIIR/Olefin copolymer compounds

Improved green strength of halobutyl at elevated temperatures was obtained via blending with semicrystalline polymers. For such improvement, a judicious selection of olefin copolymers, such as ethylene–propylene, ethylene–butene, or ethylene–octene copolymers, as blend components has to be made. Green strength enhancement was found to increase with increasing compatibility between bromobutyl (BIIR) and the olefin copolymer. Increased compatibility may be estimated by chain dimension similarity in a dilute solution between polyisobutylene and the olefin copolymer. For the most compatible olefin copolymer examined, a propylene elastomer, a phase percolation threshold was found at 0.13 volume fraction of the copolymer. This threshold value is lower than the theoretical limit of 0.156 for spherical phase domains. Based on the morphological examination by tapping phase AFM, it was found that this propylene elastomer crystallizes around the carbon black filler agglomerates to form nonspherical and high‐aspect‐ratio dispersed phases. Its phase anisotropy may contribute to its lower phase percolation threshold in BIIR compounds. Model innerliner compounds of BIIR containing 10–20 phr of such a propylene elastomer in place of natural rubber were shown to have excellent room‐temperature and improved elevated‐temperature green strengths, good aging resistance, and excellent impermeability without significant increases in relaxation time. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4447–4459, 2006