α-二亚胺镍(Ⅱ)配合物-TiCl_4复合催化剂催化乙烯原位聚合制备支化聚乙烯

Synthesis of Branched Polyethylene via Copolymerization in situ Catalyzed by (α-diimine)nickel(Ⅱ) Complex-TiCl_4 Combined and Supported Catalyst

制备了 α-二亚胺镍 ( )配合物 [C6 H5—N C( CH3)— C( CH3) N—C6 H5]Ni Br2 ( Ni L) -Ti Cl4 负载在Mg Cl2 -Si O2 载体上的复合催化剂 ( Ni L-Ti Cl4 /Mg Cl2 -Si O2 ) ,以 Al R3为助催化剂 (不用 MAO)催化乙烯聚合 .研究了 Ni L和 Ti Cl4 负载方法、Ni L/Ti Cl4 摩尔比、助催化剂种类及聚合反应温度等对催化剂性能的影响 .用 IR和 1 3C NMR表征聚合产物支化度及支链结构 ;用 GC-MS监测聚合反应 .实验结果表明 ,Ni L-Ti Cl4 复合催化剂具有齐聚原位共聚特性 ,可催化乙烯原位聚合 ,合成支化聚乙烯 .

The (α-diimine)nickel(Ⅱ){[C 6H 5—NC(CH 3)—C(CH 3)N—C 6H 5]NiBr 2}—TiCl 4(abbreviated as NiL-TiCl 4) combined catalyst which was supported by the MgCl 2-SiO 2 carrier was prepared. With alky aluminum(AlR 3) as a cocatalyst, in place of methylaluminoxane(MAO), it can catalyze ethylene polymerization and copolymerization in situ. The influences of the procedure for supporting NiL-TiCl 4, the molar ratio of NiL to TiCl 4, cocatalyst type and polymerization temperature on the catalytic performance were studied. The branching degree and the composition of the branched chain of polymerized product were investigated by IR and 13C NMR spectra. The experiment results show that the combined catalyst can be used to catalyze the synthesis of the branched polyethylene with various banched chains. The polymerization reaction was monitored by gas chromatography and mass spectrometer(GC-MS). The results show that this catalyst has the function to catalyze the oligomerization and copolymerization in situ for ethylene .