固相挤出自增强聚丙烯的性能与结构研究  

Study on mechanical properties and morphological structure of self-reinforced polypropylene by solid-phase extrusion

作　　者：綦宝文[1] 侯俊[1] 王薇莉[1] 李泽琼[2] 陈利民[1] 

机构地区：[1]四川大学高分子科学与工程学院,成都610065 [2]成都理工大学资源环境规划管理系,成都610059

出　　处：《四川大学学报（自然科学版）》2012年第3期654-660,共7页Journal of Sichuan University(Natural Science Edition)

基　　金：国家自然科学基金(20304008)

摘　　要：通过优化口模流场的拉伸应变速率,利用柱塞式挤出机(名义拉伸比为18.48),在低于聚丙烯(PP)熔点的145～155℃区间,固相挤出了自增强PP片材,拉伸强度大幅度提高,在挤出温度155℃时达到最大值378 MPa,比熔融挤出试样的强度提高了10倍多.研究了挤出工艺的影响,在155℃时固相挤出平均速率最高,试样的真实拉伸比也最大.采用DSC、XRD、SEM表征了自增强聚丙烯地微观结构和断口形貌,结果表明,自增强PP的结晶度明显提高,155℃固相挤出的PP结晶度提高了1倍,具有更高的热稳定性,片材中形成了分子链沿流动方向的高度C轴取向的α晶体,赋予了试样极高的拉伸强度.Selfreinforced polypropylene （PP） sheets were solidphase extruded through a die of optimized elongational strain rate flow field by a ram extruder with an apparent draw ratio of 18.48 in the range of 145~155 ℃ below melting point of the PP. Tensile strength of selfreinforced PP sheets was enhanced dramatically, and a maximum of 378 MPa was reached for the sheet extruded at 155 ℃, which was increased 10 times than that of the melt extrudates. The highest average extrusion rate and the maximum actual draw ratio were obtained for the PP sheet extruded at 155 ℃. Morphological structure and fractograph of the samples were characterized by DSC, XRD and SEM. The 155 ℃ extrudate had higher thermal stability and 1 time higher crystallinity than the melt extrudates. Significantly high caxis orientation of αphase crystals with molecular chains aligned along flow direction was achieved in . The PP sheet extruded at 155 ℃, leading to a very high tensile strength of the sheet.

关 键 词：自增强聚丙烯 固相挤出 高强度 C轴取向 柱塞式挤出机 

分 类 号：O631.1[理学—高分子化学]