无缺陷环氧化反式-1,4-聚异戊二烯新型合成法与性能研究

Defect-free Epoxidized Trans-1,4-polyisoprene:New Synthetic Methodology and the Property of the Resulting Polymer

在水相悬浮法的基础上,采用实验室自制的环氧化剂在弱碱性条件下合成环氧化反式-1,4-聚异戊二烯(ETPI),并且对实验的条件进行了探索,对合成出的ETPI的结构与性能进行了研究。结果表明,在反应体系中加入适当的乙酸乙酯或氯仿可以提高环氧度。其中,加入乙酸乙酯的体系中最高可获得32%的环氧度,加入氯仿的体系最高可以获得51%的环氧度。相比于传统法(采用过氧甲酸或过氧乙酸作为环氧化剂),本合成法合成出的ETPI产品均一,不会像传统合成法那样发生开环、链断裂和呋喃环形成等副反应。采用该法制备的ETPI生胶的最大拉伸强度在20MPa以上,远高于用传统方法制备的ETPI生胶(近7倍)。对ETPI的性能测试表明,随着环氧度的升高,ETPI的抗湿滑性不断提高,而滚动阻力变化不大。耐油实验表明,当环氧度大于15%时,ETPI的耐油性有明显提升。

This paper described a novel synthetic methodology towards epoxidized trans-1,4-poly isoprene （ETPI）, using a self-made oxidation reagent. Results showed that the addition of appropriate amount of ethyl acetate or chloroform to the reaction system could improve the degree of epoxidation. Epoxy degree as high as 32% in ethyl acetate, and 51% in chloroform could be obtained. Compared with the traditional method （using the peroxide or acetic acid as the oxidant）, the new synthetic method greatly suppressed the side reactions such as over oxidation, chain scission and furan ring formation, which in turn greatly improved the mechanical properties of the resulting ETPT. Mechanical tests shows that the raw ETPI prepared using this novel method shows a tensile strength over 20 MPa. almost 7 times stronger than ETPI prepared using traditional method. Improved wet-skid resistance was observed with the increase of epoxy degree for ETPI prepared using the new method, while rolling resistance changed little. Oil resistance tests showed that the oil resistance of ETPI was significantly increased when the epoxy degree was greater than 15%.