PP注塑流变性凝固层修正系数研究  

Study of Rheology Correction Coefficient of Solidified Layer in PP Injection Molding

作　　者：张涛[1] 曹阳根[1,2] 权非 邓沛然[1] 吴文云[1] 裴士轻[1] 安静[1] 

机构地区：[1]上海工程技术大学,上海201620 [2]上海信适智能科技有限公司,上海200050

出　　处：《塑料工业》2015年第10期71-74,122,共5页China Plastics Industry

基　　金：国家自然科学基金青年基金资助项目(51402189);上海工程技术大学研究生科研创新资助项目(14KY0522)

摘　　要：以聚丙烯(PP)为实验材料,考虑凝固层的影响,在内置瑞士奇石乐(Kistler)压力传感器的螺线注塑模具和CoMo Injection数据分析系统等组成的"在线"测量系统中,研究分析了均匀凝固层假设条件下的体积流率、剪切速率、表观黏度、流变性凝固层修正系数的计算原理和方法以及影响修正系数的因素。结果表明,基于本文推导出的流变性测定凝固性修正系数计算式,只需测得模温Tf及其熔体到达螺旋槽内两个压力测点间的时间差Δt(塑料熔点温度Tm为常数),即可求得该模温下的修正系数Γ,直接用于修正在线测量所得的表观黏度。因此可以简化注塑流变性测试过程,提高在线检测流变性参数的精度,有助于在线流变性测试系统的推广应用;在型腔压力一定时,表观黏度随着模温增加呈下降特性,考虑凝固层时,表观黏度受模温影响的现象减弱;凝固层修正系数Γ随模具温度的升高而下降;模具温度较低时修正系数降幅略大,整体趋势呈线性减小;随着型腔压力的增加,凝固层修正系数Γ随模具温度的减小而上升的趋势减小。Based on polypropylene （PP） as the experimental material, considering the influence of the solidified layer, in the online measuring system formed by the Archimedes spiral mold with buih-in Swiss Kistler pressure sensor and data analysis system of CoMo Injection and other components, the research analyzed the calculation principles and methods of the volume flow rate, shear rate, apparent viscosity and rheology correction coefficient of solidified layer under the condition of uniform solidified layer, and the influencing factors of correction coefficient. The results showed that based on the resultant calculation formula of solidified layer correction coefficient, just measuring the mold temperature （Tf） and the time difference （△t） of melt flow through the two pressure sensors in cavity （plastic melting temperature （Tm ） was constant ）, we could obtain the correction coefficient （Г） of the mold temperature for correctting online measurement of the apparent viscosity directly, which therefore could simplify the rheological testing process of injection molding, improve the accuracy of rheological parameters by online detection, and help to promote the use of online rheological test system. When the pressure of the cavity was constant, apparent viscosity decreased with the increase of the mold temperature. When considering solidified layer, the phenomenon of apparent viscosity affected by mold temperature decreased. Solidified layer correction coefficient （Г） decreased with the increase of mold temperature. Correction coefficient decreased slightly faster at low mold temperature, and the overall trend decreased linearly. With the increase of cavity pressure, the trend of the solidified layer correction coefficient （Г） increasing with the decrease of the mold temperature declined.

关 键 词：聚丙烯 注塑成型 流变性 凝固层 修正系数 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]