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Synthesis and characterization of hydroxyl-terminated butadiene-end-capped polyisobutylene and its use as a diol for
Kangda Wu1,2, Yibo Wu1,2, Shan Huang3,2
1Beijing Key Lab of Special Elastomeric Composite Materials, Department of Materials Science and Engineering, Beijing Institute of Petrochemical Technology Beijing 102617 China biptwkd@163.com wangh@bipt.edu.cn shangyuwei@bipt.edu.cn lishuxin@bipt.edu.cn wuyibo@bipt.edu.cn.
Abstract:
Hydroxyl-terminated telechelic polyisobutylene (PIB) was prepared through living cationic polymerization. A living PIB chain was formed using the t-Bu-m-DiCuOMe/TiCl4 initiating system and then capped with 1,3-butadiene (BD) to prepare chlorine-terminated telechelic PIB. The chlorine-terminated telechelic PIB was then hydrolysed with tetrabutylammonium hydroxide to form hydroxyl-terminated PIB. Nuclear magnetic resonance spectroscopy confirmed hydrolysis completion. The hydroxyl-terminated PIB was subsequently used as a diol to react with 4,4-methylenebis(phenylisocyanate) (MDI) and produce a PIB-based polyurethane, which showed stronger acid resistance, hydrolysis stability and thermal oxidation stability than a commercial polyurethane.
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