分子结构对聚丙烯流变及挤出发泡性能的影响  

Effects of molecular structure on rheological and extrusion foaming properties of polypropylene

作　　者：唐伊文 吕明福[1] 侴白舸 郭鹏[1] 张师军[1] 徐耀辉[1] TANG Yiwen;LV Mingfu;CHOU Baige;GUO Peng;ZHANG Shijun;XU Yaohui(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》2023年第1期89-96,共8页Petrochemical Technology

基　　金：中国石油化工股份有限公司资助项目(No.421037-1)。

摘　　要：采用GPC及多种流变表征方法研究了长支链聚丙烯(LCBPP)、宽分子量分布聚丙烯(BMWDPP)、通用线型聚丙烯的分子结构与黏弹性的关系,通过挤出发泡实验对发泡珠粒的发泡倍率和泡孔结构进行测试。实验结果表明,大分子链和长支链均可提高聚丙烯的黏弹性;不同流场和温度下松弛机制不同;LCBPP和BMWDPP均具有优良的发泡性能,BMWDPP的挤出压力更高;分子链的形态和缠结方式与聚丙烯的挤出发泡性能存在显著关联。The relationship between molecular structure and viscoelasticity of long-chain branched polypropylene(LCBPP),broad molecular weight distribution polypropylene(BMWDPP) and linear polypropylene was studied by GPC and various rheological characterization methods. The expansion ratio and cell structure of the foaming beads were tested by extrusion foaming experiments. The results show that both large molecular weight segments and long-chain branched segments can improve the viscoelasticity of polypropylene;the disentanglement mechanism isn’t the same under different flow fields and temperatures;both LCBPP and BMWDPP have good foaming properties,while BMWDPP leads to higher die pressure during extrusion;the morphology and entanglement mode of molecular chains are significantly related to the extrusion foaming properties of polypropylene.

关 键 词：分子结构 高熔体强度聚丙烯 流变 解缠结 挤出发泡 

分 类 号：TQ322.2[化学工程—合成树脂塑料工业]