This paper reports a new kind catalytic system to produce linear low density polyethylene(LLDPE) from ethylene alone in a single reactor by combining the ability of Ti(OBu n ) 4/AlEt 3 to produce 1 butene with the abi...This paper reports a new kind catalytic system to produce linear low density polyethylene(LLDPE) from ethylene alone in a single reactor by combining the ability of Ti(OBu n ) 4/AlEt 3 to produce 1 butene with the ability of [Me 2SiN t BuInd]ZrCl 2/MAO to copolymerize ethylene with 1 butene. It was found that the dual functional catalytic system has high activity and get the good polymer with density ranging from 0.91-0.95 g/cm 3 in ethylene polymerization.展开更多
Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio o...Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature. was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature.展开更多
文摘This paper reports a new kind catalytic system to produce linear low density polyethylene(LLDPE) from ethylene alone in a single reactor by combining the ability of Ti(OBu n ) 4/AlEt 3 to produce 1 butene with the ability of [Me 2SiN t BuInd]ZrCl 2/MAO to copolymerize ethylene with 1 butene. It was found that the dual functional catalytic system has high activity and get the good polymer with density ranging from 0.91-0.95 g/cm 3 in ethylene polymerization.
文摘Pentamethylcyclopentadienyl) titanium triallyioxide[Cp *Ti(OCH 2-CH[CDS1]CH 2) 3] was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature. was used as the catalyst precursor for the synthesis of polybutene 1, methylalumiunoxane(MAO) as cocatalyst. The effects of the ratio of n (Al) to n (Ti), polymerization temperature, and concentration of Ti on catalytic activity, molecular weight and chain structure were investigated in detail. The ether soluble fraction of the polybutene 1 was characterized with 13 C NMR, DSC, WAXD, and GPC. The results indicate that the polymers thus obtained are atactic and regioirregular, the weight average molecular weight of these polymers lies in the range of 3 0×10 5 to 7 0×10 5. Increasing the polymerization temperature can result in a decrease in the polymer molecular weight. But the molecular weight varies slightly with the ratio of n (Al) to n (Ti). The catalytic activity tends to decrease with the increase in polymerization temperature.