硅烷接枝热水交联聚乙烯共混物的研究

Studies on Hot water Crosslinked Silane Grafted PE Blend

本文介绍了采用过氧化二异丙苯（ ＤＣＰ） 为引发剂，二月桂酸二丁基锡（ ＤＢＴＬ） 为催化剂，在双螺杆挤出机中硅烷（ ＶＴＥＳ） 与聚乙烯（ＰＥ） 共混物的接枝反应，以及通过热水交联获得硅烷交联聚乙烯共混物。研究了不同牌号聚乙烯的选取，正交实验优化配方以及热水交联时间对产品性能的影响。结果表明：选取适当的高密度聚乙烯，低密度聚乙烯及线性低密度聚乙烯共混物进行硅烷接枝交联，可获得具有良好的力学性能和良好的加工性能的交联ＰＥ 共混物；正交实验获得ＤＣＰ、ＶＴＥＳ 及ＤＢＴＬ 的最佳用量分别为０ ．１０ 份、２ ．５ 份、０ ．１５ 份；热水交联的合适时间约为１２ 小时，在此之前拉伸强度、维卡软化点及凝胶率随交联时间而升高，断裂伸长率随时间而降低，此后，几者均趋于稳定。

s The present paper describes the silane graft reaction of PE blend in a twin screw extruder,with DCP as initiator,and DBTL as catalyst,and the preparation of silane crosslinked PE blend through hot water crosslinking process.Different PE orthogonal designing for optimal composition and the effect of hot water crosslinking time on the crosslinked PE were studied.The results indicated that the blend of HDPE,LDPE and LLDPE with an appropriate composition,had significant mechanical properties and good processing behavior.The optimal concentrations of DCP,VTES and DBTL obtained from the orthogonal designing,were 0.10 PHR,2.5 PHR and 0.15 PHR,respectively.The optimal time of hot water crosslinking was 12 hours,because tensile strength,vicat soften temperature and gel content increased,and elongation at break decreased from 0 to 12 hours while all kept constant when the crosslinking time was more than 12 hours.