熔体流变曲线特征与挤出畸变的关系  

Relationship Between Rheological Curves and Extrudate Distortions of Polymer Melts

作　　者：吴其晔[1] 李鹏[1] 王宁[1] 刘祥贵[1] 

机构地区：[1]青岛科技大学高分子科学与工程学院,山东青岛266042

出　　处：《现代塑料加工应用》2013年第4期53-56,共4页Modern Plastics Processing and Applications

基　　金：国家自然科学基金资助项目(基金号为50973050;50273016;50573037)

摘　　要：采用恒速型双筒毛细管流变仪研究熔体流变曲线与挤出畸变的关系。结果表明:有些线形链聚合物,熔体/管壁边界黏附力强,高速挤出时边界应力集中,导致剪应力曲线断裂,相应地挤出物发生表面畸变。有些长链支化聚合物,熔体弹性高,入口区应力集中,高速挤出时入口强拉伸流导致流场失稳,相应地挤出物发生整体扭曲或熔体破裂。The relationships between rheological curves and extrudate distortions of polymer melts were discussed by a capillary rheometer.The results show that for some melts with linear chains,the adsorption between melts and wall is strong,a flow stress concentration occurres at boundary by high speed extrusion,it leads to melts desorption from wall,the stress-shear rate curves break,and accordingly some regular distortions at surface of extrudate.For some melts with long branched chains,the melts elasticity is strong,then a strong flow stress concentration occurres at die inlet by high speed extrusion,it leads to the inlet drawing flow unstability,and accordingly an integral irregular distortion or melts fracture.

关 键 词：熔体流变曲线 剪应力曲线 入口压力降曲线 挤出畸变 

分 类 号：TQ320.663[化学工程—合成树脂塑料工业]