摘要
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。
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-1,4-polyisoprene was homogeneous.
出处
《合成橡胶工业》
CAS
CSCD
2011年第1期55-58,共4页
China Synthetic Rubber Industry
基金
国家科技型中小企业技术创新基金资助项目(07C26213711615)
关键词
反式-1
4-聚异戊二烯
环氧化
改性
溶液法
表征
trans-1
4-polyisoprene
epoxidation
modification
solution method
characterization