茂金属催化剂与铬系催化剂PE管材料结构性能研究

RESEARCH ON STRUCTURE AND PROPERTIES OF PIPE RESIN PRODUCED BY METALLOCENE CATALYST AND CHROMIUM-BASED CATALYST

采用凝胶渗透色谱(GPC)、核磁共振分析(13C NMR)、DSC热分级等技术研究了茂金属催化剂和铬系催化剂PE管材料的分子结构,并对DGDB2480H、QHM22F这2种管材料的静液压性能进行了测试。结果表明,QHM22F熔融温度不高,但高温条件下的静液压强度远高于DGDB2480H。由于共聚单体己烯-1在主链上的分布差异导致了两者片晶厚度分布的差异,由此导致PE管材制品在静液压性能上的差异,所以DGDB2480H不能作为PE-RT管材料用做冷热水的输送。

The molecular structures of PE pipe resins produced by metallocene catalyst and chromium- based catalyst were studied by means of gel permeation chromatography（ GPC）,nuclear magnetic resonance（13C NMR）,and DSC thermal fractionation. Hydrostatic properties of two pipe resins DGDB2480 H and QHM22 F were tested. Results show that QHM22 F has lower melt temperature but the hydrostatic properties at higher temperature are considerably higher than those of DGDB2480 H. The difference of hydrostatic properties between the two resins is due to the comonomer＇s distribution in the main chains,which result in the difference distribution of lamella thickness. That is why DGDB2480 H should not be allowed using for hot and cold water installations.