采用 CpTiCl3/I4/Zn 催化体系引发苯乙烯活性自由基聚合，之后引入乙烯，以 MAO 为助催化剂催化乙烯配位聚合，合成无规聚苯乙烯-聚乙烯嵌段共聚物 aPS-b-PE。考察了聚合温度、时间、乙烯压力和 Al/Ti 摩尔比等反应条件对共聚合的影响。使用氯仿对共聚物进行抽提，采用 GPC、DSC 和13C NMR 对氯仿可溶部分的结构和性能进行了表征。DSC 结果显示，共聚物的玻璃化转变温度 Tg 为86℃，属于无规聚苯乙烯相玻璃化转变温度，熔点 Tm 为112℃，属于聚乙烯相的熔点。13C NMR 结果证明聚苯乙烯链段为无定形态。这些表征结果表明星状羟基功能化 aPS-b-PE 共聚物是嵌段结构。% By one-pot technique,the copolymerization of styrene with ethylene promoted by CpTiCl3/I4/Zn catalytic system to produce the star-like hydroxyl functionalized S-E block copolymers was investigated via sequential monomer addition strategy in the present of methylaluminoxane(MAO) as cocatalyst for the coordination polymerization stage. The effect of temperature,time,ethylene pressure and the ratio of Al/Ti in mol on the polymerization performance was discussed. Independently from the feed composition,basic S-E block copolymer was obtained,together with aPS,from which the former was separated by solvent extraction. The CHCl3-soluble product was determined by GPC,DSC, and 13C NMR. The DSC result showed that the copolymer featured a glass transition temperature (Tg=84 ℃) which attributed to the Tg of aPS domain and melting temperature (Tm=112 ℃) which attributed to the Tm of PE domain. The block structure of the aPS-b-PE copolymer was further confirmed by 13C NMR,these results indicated that the PS segment was amorphous and the PE one was crystalline.
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