1-氯丁烷对淤浆聚乙烯催化剂性能的影响OA

Haloalkanes can be used as promoters to improve the performance of slurry polyethylene catalysts.1-Chlorobutane was adopted as a modifier to treat dissolution-precipitation titanium-based slurry polyethylene catalysts,and the catalysts were subsequently used in ethylene slurry polymerization to produce high-density polyethylene powder.The effects of 1-chlorobutane on the performance of catalysts and properties of polymers were investigated by means of SEM,GPC,DSC,and NMR.The experimental results show that 1-chlorobutane interacts with MgCl2 crystallites of the catalyst support,which leads to slight agglomeration of catalyst particles.Within an appropriate amount range,it helps narrow the particle size distribution of the catalysts.By altering the type and relative proportion of active sites on the catalysts,1-chlorobutane regulates the catalysts'hydrogen response and copolymerization performance.The optimal hydrogen response was exhibited under the treatment conditions of 1-chlorobutane amount of 3 mL,treatment temperature of 30℃,and treatment time of 2 h.To guarantee satisfactory copolymerization performance,the treatment time with 1-chlorobutane should not exceed 2 h.Additionally,the relative proportion of active sites responsible for generating low-molecular-weight polyethylene is reduced after the catalysts are treated with 1-chlorobutane.