摘要
叶片挤出机是一种基于拉伸流变的新型塑化输运设备,与常用塑料成型设备通过剪切力场来实现对聚合物及其填充体系的分散混合相比,拉伸流场具有更好的分散混合效果及较高的分散效率。通过分析叶片挤出机的结构特点,建立相应的物理模型,从理论上分析了聚合物在熔体输运阶段中拉伸形变速率的大小,得到拉伸形变速率在转角为0到/2过程中,轴向拉伸形变速率和周向拉伸形变速率大小相同,拉伸形变速率随转角呈现出抛物线变化,随着偏心距的增大而增大,随着挡板内径的增大而减小,随着转速的增大而增大;在转角为/2到过程中,轴向拉伸形变速率和周向拉伸形变速率大小也相同,拉伸形变速率随着转角的增大而逐渐减小,随着偏心距的增大而增大,随着挡板内径的增大而减小,随着转速的增大而增大。从而增大叶片结构单元的偏心距,减小挡板的内径尺寸以及在塑化加工过程中提高到适当的转速,有利于产生更强的拉伸作用。
Vane extruder is novel plasticizing equipment based on elongational flow. During the polymer processing, the materials usually suffered shear stress, however dispersive mixing is achieved more efficiently contrast under shear flow field. Through analyzing the structural features of the vane extruder, the physical model is got, then the elongational deformation rate of the melt conveying process theoretically is got. It is found that the elongational deformation rate changes differently in the process of the angle changing from 0 to n/2 and the angle changing from ~/2 to ~. At the former processing, the axial elongational deformation rate and circumference extensional rate have the same formula. The elongational deformation rate presents a parabola change as angle, it increased with the increase of eccentricity distance and rotating speed, and increased with the decrease of the inner radius of plate. The latter processing, it has the similar result. The elongational deformation rate presents attenuation as angle, it increased with the increase of eccentricity distance and rotating speed, and increased with the decrease of the inner radius of plate. Thus elongational deformation rate can be improved by increasing the eccentricity decreasing inner radius of plate as well as increasing rotating speed.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2013年第14期74-79,共6页
Journal of Mechanical Engineering
基金
'十二五'国家科技支撑计划(2011BAE15B01)
广东省数控一代示范工程(2012B011300072)资助项目
关键词
叶片挤出机
熔体输运
拉伸形变速率
Vane extruder Melt conveying Elongational deformation rate
