本体法合成反式-1,4-结构丁二烯-异戊二烯共聚物中单体定向聚合的竞聚率

Polymerizations of dienes are interesting topics in synthetic rubber fields.Stereospecific copolymerization of butadiene(Bd) and isoprene (Ip) has attracted lots of attentions due to the desirable dynamic properties of trans-1,4-Bd-Ip copolymers(TBIR) [1],including excellent fatigue properties and low heat build-up.Many investigations for the Bd and Ip copolymerization focus on the solution copolymerization,and most references focus on the synthesis of cis-1,4-Bd-Ip copolymer.In this study,the copolymerization of Bd and Ip at different feeding ratios and different reaction temperatures with supported Ziegler-Natta catalyst were investigated.According to the results of Fourier transform infrared spectroscopy and 1H-nuclear magnetic resonance spectroscopy,it was found that TBIR with high trans-1,4-unit content(the mole fraction of trans-1,4-unit of both of Bd and Ip was larger than 85％ ) were synthesized with the supported Ziegler-Natta catalyst.The TBIR compositions ( F1represents the mole fraction of Bd unit in TBIR) at different feeding ratios (f10 represents the mole fraction of Bd in the feed stock) were calculated,the results were shown in Table 1.

Reactivity ratio of monomers in synthesis of trans-1,4-butadiene-isoprene copolymer by stereospesific polymerization