OSCILLATORY SHEAR-ACCELERATED EXFOLIATION OF GRAPHITE IN POLYPROPYLENE MELT DURING INJECTION MOLDING  

作　　者：Nan Li Wei Cheng Kun Ren Feng Luo 王柯 傅强 

机构地区：[1]College of Polymer Science and Engineering,State Key Laboratory of Polymer Materials Engineering,Sichuan University

出　　处：《Chinese Journal of Polymer Science》2013年第1期98-109,共12页高分子科学（英文版）

基　　金：supported by the National Natural Science Foundation of China (No. 21074075);the program for the new century excellent talents of ministry of education of China (NCET-11-0348)

摘　　要：In this study, good dispersion status of graphite in a nonpolar, intractable polymer, i.e. polypropylene （PP）, was realized in melt processing by using a specific dynamic packing injection molding （DPIM） technique. The exfoliation extent of graphite increased remarkably from the skin zone to the core zone of the molded part, as confirmed by combination of WAXD, SEM and TEM analyses, indicating an accelerated exfoliation occurred during the DPIM processing. This phenomenon is due to decreased melt flow channel and increased melt viscosity as the solidification takes place from the wall into the center, which leads to greatly increased shear force. The good dispersion of graphite results in obvious reinforcements of both tensile strength and impact strength by adding moderate amount of graphite. The present study proposes a promising route for realizing the large-scale fabrication of structural parts of polymer/exfoliated-graphite nanocomposites with excellent mechanical properties.In this study, good dispersion status of graphite in a nonpolar, intractable polymer, i.e. polypropylene （PP）, was realized in melt processing by using a specific dynamic packing injection molding （DPIM） technique. The exfoliation extent of graphite increased remarkably from the skin zone to the core zone of the molded part, as confirmed by combination of WAXD, SEM and TEM analyses, indicating an accelerated exfoliation occurred during the DPIM processing. This phenomenon is due to decreased melt flow channel and increased melt viscosity as the solidification takes place from the wall into the center, which leads to greatly increased shear force. The good dispersion of graphite results in obvious reinforcements of both tensile strength and impact strength by adding moderate amount of graphite. The present study proposes a promising route for realizing the large-scale fabrication of structural parts of polymer/exfoliated-graphite nanocomposites with excellent mechanical properties.

关 键 词：Polymer-matrix composites Mechanical properties Injection moulding. 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]