PETA/St双单体聚丙烯挤出改性及其发泡性能研究  

Study on Modification and Foaming Properties of PP Through PETA/St Double-Monomer Reactive Extrusion

作　　者：郭天浩 陆奕权 刘涛[1] 赵玲[1,2] GUO Tianhao;LU Yiquan;LIU Tao;ZHAO Ling(State Key Laboratory of Chemical Engineering,East China University of Science and Technology,Shanghai 200237,China;School of Chemistry&Chemical Engineering,Xin Jiang University,Urumqi 830046,China)

机构地区：[1]华东理工大学,上海市多相结构材料化学工程重点实验室,上海200237 [2]新疆大学化学化工学院,乌鲁木齐820046

出　　处：《中国塑料》2020年第7期1-9,共9页China Plastics

基　　金：国家重点研发计划(2016YFB0302200)。

摘　　要：以季戊四醇三丙烯酸酯(PETA)和苯乙烯(St)为接枝单体,采用反应挤出改性制备具有长支链结构的聚丙烯(LCBPP)。使用红外光谱、差示扫描量热仪、流变测试等表征材料的可发泡性,并通过扫描电子显微镜观测发泡材料的泡孔形貌。并以CO2为发泡剂进行了间歇熔融发泡实验以评估聚丙烯(PP)的熔融发泡性。结果表明,在未交联改性PP中,用2%(质量分数,下同)PETA和3%St改性的PP各项性能最好;改性PP具有不同程度的应变硬化现象,这归因于不同程度的长链支化结构;改性后具有长链支化结构的PP有较好的发泡效果,PP-g-PETA/St样品的发泡温度窗口为25℃,最高发泡倍率达到33倍,此时泡孔平均直径为36μm,泡孔密度为3.17×10^8个/cm^3。A series of long-chain branched PP compounds were prepared by double-monomer reactive extrusion of conventional isotactic polypropylene with pentaerythriol triacrylate(PETA)and Styrene(St),their faomability was characterized with FTIR,DSC and rheology tests,and their foam structure was observed with SEM.The results indicated that for the modified PP samples without crosslinking structure,the PP compound with 2 wt%of PETA and 3 wt%of St exhibited the optimum comprehensive performance.Meanwhile,the PP compounds showed a different strain hardening behaviors because of the different branching structure.The batch melt foaming experiment was conducted to evaluate the melt foamability of PP compounds with CO2 as the foaming agent.It was found that the PP compounds with a long branching structure had a better melt foamability,and the the PP samples showed a foaming window temperature of 25℃after grafted with PETA/St double monomers.The resulting PP foams achieved a maximum expansion ratio of 33,an average diameter of 36μm,and a cell density of 3.17×10^8 cells/cm^3.

关 键 词：长链支化结构 改性聚丙烯 流变性能 发泡 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]