(2-Me-3-ClPh)_2PBIMe_2FeCl_2racC_2H_4(Ind)_2ZrCl_2/MAO双功能催化体系乙烯原位共聚制备LLDPE

合成了后过渡金属铁 (2 Me 3 ClPh) 2 PBIMe2 FeCl2 低聚催化剂 ,并与亚乙基桥茂金属共聚催化剂rac C2 H4 (Ind) 2 ZrCl2 共用 ,用MAO(1 4mol L甲苯溶液 )作为助催化剂 ,原位共聚合成线性低密度聚乙烯 (LLDPE) .结果发现 ,这种后过渡铁催化剂具有很高的低聚催化活性 1 0× 10 7goligomer (molFe·h) ],双功能催化体系的催化活性保持在 10 6 gPE (molFe·h)以上 ;1 3C NMR分析表明 ,得到了线性低密度聚乙烯 ,当Fe Zr比为 1 2时 ,也没有出现α 烯烃残留现象 ,说明这两种催化剂具有好的匹配性 ;随Fe Zr比和反应温度的变化 ,聚合物的熔点、结晶度、熔点等均表现出很好的规律性 .

LLDPE PREPARATION BY in situ COPOLYMERIZATION OF ETHYLENE USING MATALLOCENE/(2-Me-3-ClPh)2PBIMe2 FeCl2/MAO TANDEM CATALYZERS

A novel late transitional metal catalyst-(2-Me-3-ClPh) 2PBIMe 2FeCl 2——has been synthesized having a high oligomerization activity up to 1.0×107g oligomer/(mol Fe·h).Using this oligomerization catalyst and metallocene catalyst—rac-C-2H-4(Ind) 2ZrCl 2—as a dual functional catalyst system,MAO as the only cocatalyst,Linear Low Density Polyethylene (LLDPE) has been prepared by in situ copolymerization of ethylene having a high activity >106g PE/(mol cat·h)]. 13C-NMR shows that the LLDPE is obtained.In addition,the presence of unreacted α-olefin was not detected since there is no evident resonance signal at 29.29 and 29.42,which proves that this dual functional catalyst system has a good match during in situcopolymerization.With increasing the Fe/Zr ratio,the densities of polymers and the melting points of polymers obtained from DSC are in a descending trend.Meanwhile,the similar phenomenon is also found when the reaction temperature decreases.