低分子可萃取物含量对PA 6热性能及加工性能的影响  

Effect of extractable oligomer content on thermal property and processability of PA 6

作　　者：方运华 刘嘉茜 王朝生[1] 吉鹏[2] FANG Yunhua;LIU Jiaxi;WANG Chaosheng;JI Peng(State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,College of Material Science and Engineering,Donghua University,Shanghai 201620;Co-innovation Center for Textile Industry,Donghua University,Shanghai 201620)

机构地区：[1]东华大学材料科学与工程学院纤维材料改性国家重点实验室,上海201620 [2]东华大学纺织产业关键技术协同创新中心,上海201620

出　　处：《合成纤维工业》2019年第6期16-22,共7页China Synthetic Fiber Industry

基　　金：国家重点研发计划项目(2017YFB0309400);中央高校基本科研业务费专项资金资助(10617440)

摘　　要：以未萃取的聚己内酰胺(PA6)切片为原料,通过控制萃取时间制备不同低分子可萃取物含量PA6(cPA6)切片,探讨了低分子可萃取物含量对cPA6的热性能及高温下加工性能的影响,分析了cPA6的非等温结晶动力学。结果表明:随着低分子可萃取物含量的增多,cPA6的初始结晶温度与结晶峰温度都向高温区移动,cPA6的熔融温度无明显变化,低分子可萃取物含量的变化对cPA6的起始分解温度与最大分解速率温度的影响也很小;随着低分子可萃取物含量的增加,cPA6的结晶过程由均相成核向异相成核转变,cPA6的结晶速率先增大后减小,并在低分子可萃取物质量分数为2.5%时取得最大值,低分子可萃取物的存在对cPA6的结晶活化能影响不大;相同温度下,少量的低分子可萃取物会使cPA6的表观黏度增大,而大量的低分子可萃取物存在会导致其表观黏度的降低与波动,导致其热加工性能的不稳定。Polycaprolactam chips with different extractable oligomer content(cPA 6)were prepared using traditional unextracted PA 6 chips by controlling extraction time.The influence of extractable oligomer content on the thermal properties high-temperature processability of cPA 6 was discussed.The non-isothermal crystallization kinetics of cPA 6 was analyzed.The results showed that the initial crystallization temperature and crystallization peak temperature of cPA 6 moved to the high temperature region and the melting temperature did not obviously change with the increase of extractable oligomer content,and the change of the extractable oligomer content had a little effect on the initial decomposition temperature and the temperature of the maximum decomposition rate;the crystallization process of cPA 6 changed from homogeneous nucleation to heterogeneous nucleation,the crystallization rate increased first and then decreased with the increase of extractable oligomer content,and the crystallization rate was maximized when the mass fraction of extractable oligomer was 2.5%,which implied that the existence of extractable oligomer had a little effect on the crystallization activation energy of cPA 6;at the same temperature,a small amount of extractable oligomer would increase the apparent viscosity of cPA 6 while a large amount of extractable oligomer would lead to the decrease and fluctuation of the apparent viscosity,resulting in the instability of the hot processing performance.

关 键 词：聚己内酰胺 低分子可萃取物 非等温结晶动力学 结晶活化能 流变性能 

分 类 号：TQ323.6[化学工程—合成树脂塑料工业]