摘要
Although an important industrial catalyst for producing high density polyethylene,the SiO_(2)-supported organosilyl chromate UCC S-2 catalyst has not been fully investigated compared with the SiO_(2)-supported oxo chromium Phillips catalyst.In this work,gas phase ethylene polymerization by S-2 catalysts(Cat-1,Cat-2,and Cat-3)was carried out in a high-speed stirredautoclave reactor.The effects of temperature,time,and pressure on kinetics,activity,and product properties were studied.All kinetics were typical built-up types with slow decay.Compared to the simple physical mixtures of Cat-1 and Cat-2,Cat-3 showed higher activity and its product had a broader molecular weight distribution,indicating new active species induced during blending of Cat-1 and Cat-2 in n-hexane.The innovation by a simple catalyst technology created a new application to meet market demands.
基金
The authors were grateful to the Key Projects in the National Science&Technology Pillar Program during the 11th Five-Year Plan Period(2007BAE50B04)
Qilu Branch Co.,SINOPEC for the financial support.