宽峰或双峰分布两段聚合聚乙烯树脂性能研究Study on Performance of Two Stage Polymerization of HDPE Resin with Broad or Bimodal Molecular Weight Distribution
薛锋;马广生;
摘要(Abstract)：
用两段淤浆聚合工艺合成了具有宽峰或双峰相对分子质量分布的高密度聚乙烯(HDPE)／(乙烯／丁烯-1)共聚树脂的反应釜共混聚合物。随着丁烯-1用量的增加,共混物的密度、熔点、结晶度、拉伸屈服应力减小,而断裂伸长率增加。随着高相对分子质量共聚物的含量增加,熔点、密度、结晶度减小,相对分子质量分布的双峰特性也更明显。通过调整两段聚合物的熔体流动速率、两段聚合物之比来控制相对分子质量大小及其分布。控制第一段小分子数目,增加第二段相对分子质量或减小密度可获得最大耐环境应力开裂性能。
关键词(KeyWords)： 高密度聚乙烯;宽峰或双峰相对分子质量分布;力学性能;流变性能
基金项目(Foundation):
作者(Authors): 薛锋;马广生;
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