Epoxidation is a convenient approach to incorporate polar epoxy groups in the polybutadiene chains, which could change non-polar styrene-butadiene-styrene block copolymer (SBS) into polar epoxidized SBS (ESBS)[1]. Among the oxidants reported previously, in-situ generated peracetic acid from hydrogen peroxide and formic acid was used widely because of its low price and high security[2]. However, hydrogen peroxide and formic acid are incompatible with organic solvent in the system, which will lead to ring-opening reaction of epoxy groups and reduce epoxidation degree of ESBS. In this work, five kinds of phase transfer catalysts were used to improve epoxidation degree of ESBS and restrain ring-opening of epoxy groups.%研究了三辛基甲基氯化铵(MTAC)、三十二烷基三甲基氯化铵(TMAC)、十六烷基三甲基溴化铵(HTAB)、十八烷基三甲基溴化铵(OTAB)以及聚乙二醇(PEG-400)等5种相转移催化剂对苯乙烯-丁二烯-苯乙烯嵌段共聚物环氧化反应的影响.结果表明,MTAC的环氧化效果最好,当其质量分数为1.0%时,可使环氧化苯乙烯-丁二烯-苯乙烯嵌段共聚物(ESBS)的环氧基质量分数从18.1%提高到20.1%;HTAB和PEG-400有利于ESBS的环氧基质量分数的提高;而OTAB和TMAC由于自身较大的分子体积反而使ESBS的环氧基质量分数下降.傅里叶变换红外光谱分析表明,MTAC可以有效抑制环氧基开环副反应的发生.
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