宽峰聚乙烯／蒙脱土纳米复合材料的制备

利用2种不同的方法制备了2种氢调敏感性不同的蒙脱土／氯化镁／四氯化钛（MMT／MgCl2／TiCl4）催化剂，利用这2种催化剂及其混配催化剂，通过原位聚合法，制备出一系列宽峰聚乙烯纳米复合材料，采用X_射线衍射仪（XRD）、凝胶色谱测试分析（GPC）及力学性能测试等方法对催化剂及聚合产物进行分析，结果表明，2种催化剂以及按照不同比例混合的混配催化剂均表现出较高的聚合活性，XRD测试结果表明，蒙脱土片层在乙烯聚合过程中发生了插层及剥离，以单片层或几层共存的形式分散于聚乙烯基质中；用混配催化剂可制得宽峰聚乙烯纳米复合材料，Mw／Mn=7．23，并且聚合物的堆积密度达到工业生产的标准，宽峰聚乙烯纳米复合材料的综合力学性能较工业产品5000S及工业上应用的管材料有很大的提高。

Preparation of broad molecular weight distribution polyethylene nanocomposites

In this dissertation, two category ＂intercalation catalyst of＂ （MMT/MgCl2/TiCl4）, which showed different response to hydrogen regulation, were prepared and a series of broad molecular weigh distribution （MWD） polyethylene/MMT nanocomposites were synthesized via in-situ polymerization by using hybrid catalysts. The exfoliation of the layered silicates in the composites was confirmed by XRD and polymerization products were researched by the GPC and mechanical performance test. The 001 diffraction peak of the MMT in the composites measured by X-ray test disappeared, MMT layers observed by TEM revealed that they have been exfoliated in PE matrix. MI showed that processing properties were much better. The broad molecular weight distribution characteristic for the composites was revealed by the GPC profile （Mw/Mn = 7.23）, which was mainly due to different response to hydrogen regulation for active sites generated by hybrid catalysts. Comprehensive mechanical performance of broad peak polyethylene nanocomposite has been greatly improved than industrial product 5000S and the pipe material for industrial application