拉伸工艺对聚丙烯片材结晶取向及拉伸强度的影响  

Effect of orientation processing on crystalline,orientation and tensile strength of polypropylene sheet

作　　者：张冯倩 高达利[1] 初立秋[1] 侴白舸 赵雅超 张师军[1] Zhang Fengqian;Gao Dali;Chu Liqiu;Chou Baige;Zhao Yachao;Zhang Shijun(Sinopec Beijing Research Institute of Chemical Industry,Beijing 100013,China)

机构地区：[1]中国石化北京化工研究院,北京100013

出　　处：《石油化工》2022年第11期1289-1293,共5页Petrochemical Technology

摘　　要：采用不同拉伸工艺参数制备了取向聚丙烯片材,并利用DSC、WAXD和万能拉伸性测试等方法研究了拉伸倍率、拉伸温度等工艺参数对取向聚丙烯片材的熔融和结晶行为、取向度及力学性能的影响。实验结果表明,拉伸作用下聚丙烯分子链产生取向排列和重结晶,形成高度有序的结晶形态;提高拉伸倍率可以显著增加片晶的取向度和结晶度;拉伸过程中形成的高度有序的结晶形态有利于改善片材的机械性能,所得取向聚丙烯片材的力学性能显著提高,拉伸强度可达418 MPa左右;拉伸倍率一定时,随着拉伸温度的升高,聚丙烯片材的取向度和力学性能呈先升高后降低的趋势;拉伸温度为142℃时,聚丙烯片材的取向度和拉伸强度达到最大值。The oriented polypropylene sheets were prepared by different orientation processing conditions,and the effects of process parameters such as draw ratio and draw temperature on the melting-crystallization behavior,orientation degree and mechanical properties of oriented polypropylene sheets were studied by DSC,WAXD and universal tensile test.The results show that the orientation arrangement and recrystallization were occurred along the tensile direction,forming a highly ordered crystalline morphology.Moreover,a higher draw ratio resulted from the higher orientation degree and crystallinity.During the drawing process,the highly ordered crystalline morphology formed is conducive to improve the mechanical properties of the sheet,and the mechanical properties of the oriented polypropylene sheet obtained are significantly improved,with the tensile strength reaching about 418 MPa.When the draw ratio is constant,the orientation degree and mechanical properties of polypropylene first increase and then decrease as the draw temperature increasing.When the draw temperature is 142℃,the orientation degree and tensile strength of polypropylene reach the maximum.

关 键 词：聚丙烯 取向 结晶 拉伸强度 

分 类 号：TQ325.1[化学工程—合成树脂塑料工业]