新型高效淤浆工艺聚乙烯催化剂的制备及其催化性能

采用浸渍法制备了新型高效淤浆工艺聚乙烯催化剂(BCE催化剂)。研究了其组成、粒径分布、微观形态和对乙烯淤浆聚合的催化性能,并与国产、进口两种同类催化剂进行了比较。研究结果表明,在己烷为溶剂、聚合温度80℃、聚合时间2h、氢气压力0.28MPa、乙烯压力0.45MPa的条件下,BCE催化剂的催化活性(每克T i每小时产生的聚乙烯的质量)达351kg/(g.h),与国产、进口两种同类催化剂的催化活性适当;BCE催化剂所得聚合物的颗粒形态呈较大类球形,所得聚合物的细粉含量较少,粒径为75~850μm之间的粒子的质量分数为96.7%;BCE催化剂的氢调敏感性好。

Preparation of Novel Polyethylene Catalyst for Slurry Process and Its Catalytic Performance

A novel polyethylene catalyst(BCE catalyst)with high performance for slurry process was prepared by precipitation.BCE catalyst was introduced and compared with two other commercial catalysts.Composition of catalysts was determined by elemental analysis.Morphologies and particle size distributions of catalysts were investigated.Ethylene polymerization and particle size distribution of obtained polymers were studied.Catalytic activity of BCE catalyst was(mass of polyethylene per gram Ti per hour)351kg/(g·h)in ethylene polymerization under polymerization conditions:solvent,hexane;temperature,80℃;time,2h;hydrogen pressure,0.28MPa and ethylene pressure,0.45MPa.Morphologies of polyethylene particles obtained with BCE catalyst were in form of relatively large spheres,which were favored by polyethylene slurry-gas combined process.Mass fraction of polyethylene particle with diameter of 75~850μm obtained with BCE catalyst amounted to 96.7%.BCE catalyst was sensitive in hydrogen responsibility.