含大位阻基团苯氧亚胺锆催化剂的合成及在制备UHMWPE中的应用

Synthesis of Bis (phenoxy-imine) Zr Complex Bearing Bulky Substituents and Its Use in Preparation of UHMWPE

合成了酚氧基邻位上含有大位阻基团的双[(N-3,5-二枯基亚水杨醛)-2’-甲基环己胺]二氯化锆催化剂(Cat),并将其应用于乙烯均聚制备超高分子量聚乙烯(UHMWPE)。研究了以甲苯为溶剂,不同助催化剂、n(Al)/n(Zr)、聚合时间、聚合温度条件下,对Cat催化乙烯的聚合活性、UHMWPE相对分子质量的影响。结果表明,Cat在以甲基铝氧烷(MAO)或烷基铝为助催化剂,n(Al)/n(Zr)=50000,聚合时间为2h,聚合温度为50℃的条件下可高效催化乙烯聚合获得UHMWPE,催化活性大于200×10~6 g PE/mol Zr;尤其在三甲基铝(TMA)助催化剂的存在下,可获得黏均相对分子质量达到8×10~6的UHMWPE。

Bis(N-(3,5-dicumylsalicyidene)-2’-methylcyclohexanaminato)zirconium dichloride(Cat)bearing steric bulky substituent at the ortho position of phenoxyl group was synthesized.Its catalytic behaviors in ethylene homopolymerization to prepared UHMWPE were investigated.The effects of polymerization parameters,such as kinds of cocatalyst,Al/Zr mole ratio,polymerization time,polymerization temperature on polymerization performance were carefully examined,respectively.The results show that under the condition of n(Al)/n(Zr)50000,polymerization time 2 h,the complex shows an activity of more than 200×10^6 g PE/mol Zr at 50℃.Besides,the UHMWPE with molecular weight of 8 million is obtained when the cocatalyst is trimethylaluminum(TMA).