含酚单茂钛催化体系催化乙烯均聚及乙烯/1-己烯共聚

Ethylene homopolymerization and ethylene/1-hexene copolymerization using phenol containing monotitanocene catalytic system

制备了不同取代基的含酚单茂钛配合物,并对配合物结构进行了表征,通过单晶XRD表征确定了配合物的具体结构。以该类配合物为主催化剂,与三异丁基铝/三苯甲基四(五氟苯基)硼酸盐组成催化体系,进行了乙烯均聚及乙烯/1-己烯共聚性能测试,得到一系列具有不同结构的聚乙烯和聚烯烃弹性体产品,探索了不同取代基的含酚单茂钛配合物的乙烯均/共聚规律,并对聚合物进行了DSC和GPC表征。实验结果表明,乙烯均聚时,该催化体系聚合活性最高达到3480 kg/(mol·h),聚乙烯的重均分子量高于1.81×10^(5)、分子量分布指数为2.43~3.01、熔点高于134.7℃;在乙烯共聚时,共聚物密度为0.865~0.874 g/cm^(3),与通用乙烯共聚弹性体的密度相近。

Phenol containing monotitanocene complexes with different substituents were prepared.The structures of the new complexes were characterized,and the specific structures of the complexes were determined by single crystal XRD.Using the complexes as the main catalyst,the catalytic system composed of triisobutyl aluminum/triphenylmethyltetra(pentafluorophenyl)borate,and their properties for ethylene homopolymerization and ethylene/1-hexene copolymerization were tested.The law of ethylene homo/co polymerization under different ligand substituents was explored,and a series of polyethylene and polyolefin elastomer products with different structures were prepared.The polymers were characterized by DSC and GPC.The results show that the highest polymerization activity of the catalytic system is 3480 kg/(mol·h)in ethylene homopolymerization,the average molecular weight of polyethylene is higher than 1.81×10^(5) with molecular weight distribution index between 2.43 and 3.01,and melting point of polyethylene is higher than 134.7℃.In ethylene copolymerization,the copolymer density is 0.865-0.874 g/cm^(3),which is similar to that of general ethylene copolymer elastomer.