【摘要】 采用升温淋洗分级技术将国产茂金属催化剂制备的茂金属聚乙烯树脂分级,对部分分级样品进行核磁共振碳谱、差示扫描量热和凝胶渗透色谱测试.发现分级样品结晶度分布窄,支链含量对热性能的影响很大,在多分散性上表现为高分子量链上的支链含量低。更多还原

【Abstract】 The metallocene based polyethylene (mPE) from copolymerization of ethylene and 1 - hexene was fractionated by means of preparative temperature - rising elution fractionation (TREF) technique. Some fractions were selected and characterized by nuclear magnetic resonance (13C - NMR), differential scanning calorimetry (DSC) and gel permeation chromatography (GPC). It was found that the crystallinity distribution of the mPE was narrow, and the thermal properties of the mPE were significandy influenced by the content of short - branched chain. The analysis on the dispersion of the system indicated that the high molecular weight fractions corresponded to the low content of short - branched chain.更多还原