聚甲醛熔体挤出流动性能和挤出胀大的研究  

Flow Properties and Extrudate Swell During Extrusion of Polyformaldehyde Melt

作　　者：梁基照[1] 何柳[1] 

机构地区：[1]华南理工大学机械与汽车工程学院,广东广州510640

出　　处：《现代塑料加工应用》2010年第4期22-24,共3页Modern Plastics Processing and Applications

摘　　要：应用流动速率仪，在温度170～220℃和载荷1．2～12．5kg的条件下，考察了剪切速率（γ）、剪切应力（τw）及温度等对聚甲醛熔体流动特性和挤出胀大的影响。结果表明，熔体的剪切流动基本上服从幂律定律；熔体的表观剪切粘度对温度的依赖性大致上符合Arrhenius方程；表观剪切粘度随着γ和τw的增加而非线性减小；挤出胀大比随着温度的升高而近乎线性下降，随着τw和γ的增加而呈非线性增大。The influences of shear rate, shear stress and temperature on the flow properties of POM melts were investigated by using a melt flow indexer at 170-220 ℃ ,and loadings ranging from 1. 2 kg to 12. 5 kg. The results show that the melt shear flow obeys roughly the power law; the dependence of the melt apparent shear viscosity on temperature corresponds approximately with the Arrhenius equation; the melt apparent shear viscosity of POM decreases nonlinearly with the increase of shear rate and shear stress;the melt extrudate swell ratio decreases roughly linearly with increase of the temperature, while increases nonlinearly with increasing the shear stress and shear rate.

关 键 词：聚甲醛 熔体 流动性能 挤出胀大 

分 类 号：TQ326.51[化学工程—合成树脂塑料工业]