The epoxidized trans-1,4-polyisoprene (ETPI) with different epoxidation degree was synthesized with peracetic acid as oxidant in the chloroform solution of trans-1,4-polyisoprene(TPI). Fourier transform-infrared spectroscopy ( FTIR ), hydrogen nuclear magnetic resonance spectroscopy (1H-NMR) were used to measure the epoxidation degree of ETPI, and differential scanning calorimetry was used to analysis thermal performances. The results showed that the high epoxidation degree of ETPI(up to 80％ ) could be synthesized by solution method at the appropriate temperature of 30 ℃. The epoxidation degree could be controlled by regulating the mole ratio of peroxyacetic acid to the double bond of trans-1,4-polyisoprene owing to the fact that the epoxidation basically obeyed stoichiometric relationship. The results of FTIR and 1H-NMR confirmed that the epoxy group had been introduced in the molecular chain, and there was a good linear relationship between FTIR and 1H-NMR epoxidation degree measurement results. The crystallization of ETPI was all destroyed when the epoxidation degree exceeded 38％. The glass transition temperature increased with increasing epoxidation degree, and there was a good linear relationship between both.ETPI containing different epoxidation degree all had only one glass transition temperature, indicating the epoxidation modification of trans-l, 4-polyisoprene was homogeneous.%以过氧乙酸为环氧化剂,在反式-1,4-聚异戊二烯(TPI)的氯仿溶液中进行环氧化反应,获得了具有不同环氧度的环氧化反式异戊橡胶(ETPI),用红外光谱和核磁共振氢谱对其进行了表征,并通过差示扫描量热分析研究了其热性能.结果表明,用溶液法能够合成出环氧度较高(最高可达80%)的ETPI,合适的反应温度为30 ℃;环氧化反应基本按化学计量进行,可通过调节过氧乙酸与TPI双键的摩尔比来控制环氧度.红外光谱和核磁共振氢谱的分析结果证实TPI经改性后已经在分子链上引入了环氧基团,两种方法测得ETPI的环氧度具有较好的线性关系.ETPI的环氧度超过38.0%后结晶完全被破坏,玻璃化转变温度则随其环氧度增加而升高,二者呈线性关系;环氧度不同的ETPI都只显示出1个玻璃化转变温度,说明在TPI分子主链上的环氧化改性是均匀的.
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