六氯化钨/二氯乙基铝/乙醇引发开环易位聚合反应制备反式聚辛烯橡胶

trans-polycyclooctene rubber prepared by ring-opening metathesis polymerization with WCl_6/EtAlCl_2/EtOH

以六氯化钨(WCl_6)为催化剂、二氯乙基铝(EtAlCl_2)为助催化剂、乙醇(EtOH)为活化剂引发环辛烯(COE)的开环易位聚合反应,制备了反式聚辛烯橡胶(TOR),考察了聚合反应的影响因素,并研究了α-烯烃种类及用量对TOR的数均分子量及其分布的影响。结果发现,在单体COE浓度为0. 41 mol/L、EtAlCl_2/WCl_6(摩尔比)为4、EtOH/WCl_6(摩尔比)为2、反应温度和时间分别为0℃和1 h时,可制得反式摩尔分数20%～65%的TOR,产率可达到90%左右,数均分子量为4×10~4～70×10~4,分子量分布指数为1～2;加入1-辛烯或1-己烯可以调控TOR的数均分子量及其分布,且加入1-己烯调节的TOR的数均分子量明显小于加入1-辛烯调节者。

With tungsten hexachloride as the cata- lyst, ethyl aluminum dichloride as the cocatalyst and ethanol as the activator, trans-polycyclooctene rub- ber（TOR） was prepared by ring-opening metathesis polymerization of cyclooctene. Effect factors on polymerization were investigated, and the effects of tx-olefin on the number-average molecular weight and its distribution of TOR were studied. The results showed that when the monomer concentration was 0.41mol/L （in toluene） , the ratio of EtAlCl2/WCl6 and EtOH/WCl6 was 4 and 2, respectively, and the reaction temperature and time was 0℃ and 1 h, TOR with mole fraction of trans-unit of 20% -65% were prepared. The yield of TOR could reach about 90% , number-average molecular weight was 4 × 10^4 - 70 × 10^4 , and the molecular weight distribution was 1 -2. When 1-ocenene or 1-hexene could adjust the number-average molecular weight and its distribution of TOR, and the number-average molecular weight of TOR with 1-hexene was smaller than those of TOR with 1-octene.