以Ph3CB(C6Fs)4/iBu3Al作为助催化体系,研究了单氯半茂型催化剂,ClCp' Zr[X-2-R1-4-R2-6-(Ph2P=0)C6H2]2 (CP'=C5H5,a:X=O,R1=Ph,R2=H;b:X=O,R1=F,R2=H;c:X=O,R1=tBu,R2=H;d:X=O,R1=R2=tBu;e:X =O,R1 =SiMe3,R2 =H;f:X =S,R1=SiMe3,R2 =H;Cp'=C5Mes;g:X=O,R1=SiMe3,R2=H)的乙烯高温(50～125℃)聚合行为.结果表明,催化剂a～d可在高温(50～100℃)下高效引发乙烯聚合,最佳反应温度为75℃.适当增大R1取代基的位阻或引入吸电子取代基均有利于提高催化活性.三甲基硅烷基取代的催化剂e耐高温性能较催化剂a～d大大提升,在100℃时,乙烯聚合活性可达5628 kg/(mol Zr·h).金属中心的配位原子及茂环上取代基团的改变对催化活性和聚合物的相对分子质量分布有一定的影响.
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