烷基硫醇诱发苯乙烯马来酸酐共聚合的研究

<正> 硫醇由其上S—H弱键易遭受自由基进攻而用作调聚剂是熟知的。硫醇作为氧化-还原体系的一个组成促进丁苯乳液聚合也有报道,但单独硫醇,在相当于引发剂的用量范围内及常温条件下,诱发烯类单体或CTC(电荷转移络合物)型单体对的共聚报道极少。我们发现了微量硫醇在常温下对苯乙烯(St)、马来酸酐(MAn)共聚的催化效应,并

INVESTIGATIONS ON COPOLYMERIZATION OF STYRENE/ MALEIC ANHYDRIDE INDUCED BY ALKYLTHIOLS

Accelerating effects of alkylthiols on copolymerization of Charge-Transfer-Complex (C. T. C.) comonomers were discovered for the first time. Experiments indicate that St/MAn (1:1) can hardly copolymerize spontaneously at 37℃, but in the presence of trace amount of thiols (RSH) the copolymerization occurs rapidly. In the range of 1.7×10-4-3.4×10-3 mol-1 for (RSH), initial rates, Rpo, almost remain constant. If set (St + MAn)= constant, Rpo, increase monotonically with increasing MAn] . Furthermore, when feed ratio Xma = 0.08 -0.083, the compositions of copolymers vary from 0.28-0.33. In other words, regardless of comonomer feed ratio, MAn contents in resultant eopolymers are always far lower than that of "ideal alternative copolymer", as it was frequently reported.