链结构对硅烷接枝交联聚乙烯的影响

The Effects of Chain-Structure of Polyethylene on the Grafting of Viny1 Silane onto PE and Crosslinking of Silane Grafted PE

以双螺杆挤出机为反应器，制备了一系列硅烷接枝聚乙烯。通过对接枝物的ＩＲ分析、交联行为、高温应力－应变曲线及力学性能的测定，研究了聚乙烯大分子链结构对乙烯基硅烷与聚乙烯的熔融接枝反应和交联行为的影响。结果表明：聚乙烯大分子链结构对接枝反应起着非常重要的作用，在相同接枝工艺条件下，三种聚乙烯（ＬＤＰＥ、ＨＤＰＥ、ＬＬＤＰＥ）硅烷接枝率大小顺序为：ＬＤＰＥ＞ＬＬＤＰＥ＞ＨＤＰＥ。研究结果还表明，硅烷接枝率和聚乙烯的聚集态结构影响接枝物的交联速度。相同交联条件下，交联速度顺序为：ＬＬＤＰＥ＞ＬＤＰＥ＞ＨＤＰＥ。

A series silane grafted polyethylenes were prepared by using the twin screw extruder.The effects of the sort of PE on grafting and crosslinking reactions were investigated by using the IR analysis,crosslinking behavior,DSC measurements and the thermal loading.It was foud that the molecular structure of PE played an importent role in the grafting reactions.The grafting effeciency of three types PE(LDPE,HDPE,LLDPE)varied with the order:LDPE>LLDPE>HDPE.It was also found that the rate of crosslinked PE influenced by the difference of the silane grafting effeciency and its solid state (crystallinity) of various PE.