摘要
将松弛时间较长的聚对苯二甲酸乙二醇酯(PET)动态挤出后淬火"冷冻"其熔体的分子链缠结状态,然后在差示扫描量热仪(DSC)上升温到玻璃化转变温度以上进行结晶。通过分析 PET 熔体的动态流变参数和结晶动力学过程的变化,间接证实动态挤出聚合物熔体分子的解缠结作用。结果发现,正弦脉动挤出流场对聚合物分子链造成的解缠结效果不仅可以降低聚合物熔体的加工黏度,还可以明显降低 PET 的结晶温度,结晶峰向低温移动且次峰强度明显增大,低温结晶峰含量随振幅和频率的增加而增大,在振幅为0.3 mm、频率为12 Hz 时达到60.7%,成为主结晶过程。
The dynamic rheological behavior and non-isothermal cold crystallization of poly（ethylene terephthalate） （PET） were studied to reflect the disentanglement effect of the pulsatile extrusion flow field. The extruded PET was quenched with ice water to hold the melt entanglement state and then to pursue its non-isothermal cold crystallization by a DSC. The results showed that the disentanglement effect of the pulsatile extrusion flow could not only reduce the viscosity of PET melt, but also the crystallization temperature. The peak at low temperature of the non-isothermal crystallization increases with the vibration frequency and amplitude. The proportion of the crystallization at low temperature is 60.7 % while the vibration arnlitude is 0.3 mm and the frequency is 12 Hz.
出处
《中国塑料》
CAS
CSCD
北大核心
2006年第12期56-59,共4页
China Plastics
基金
国家自然科学基金重大项目资助(10590351)
华南理工大学资助项目(B02E5050470)
关键词
正弦脉动挤出
解缠结
动态流变
非等温结晶动力学
聚对苯二甲酸乙二醇酯
pulsatile extrusion
disentanglement
dynamic rheological behavior
non-isothermal crytallization
poly（ethylene terephthalate）
