熔融缩聚耐高温PA10T/10I的非等温结晶动力学研究

Non-isothermal crystallization kinetics of melt polycondensation PA10T/10Iwith heat-resistant

采用癸二胺、对苯二甲酸和间苯二甲酸为原料,通过熔融缩聚法制备了耐高温共聚酰胺10T/10I(PA10T/10I),并通过差示扫描量热仪对不同PA10I单元含量的PA10T/10I的非等温结晶动力学进行了研究。结果表明:随着PA10I单元含量的增加,在相同降温速率下,PA10T/10I聚合物结晶峰温度降低,相对结晶度增大;在较低的降温速率下,结晶时间缩短,但降温速率较高时,结晶时间又有所延长。通过Jeziorny法处理发现PA10T/10I成核可能同时包含均相成核和异相成核,PA10I单元质量分数超过5%后,结晶前期晶体增长速率较快,后期晶体生长空间缩小,生长向低维转变;通过Mo法处理发现随着PA10I单元含量增加,PA10T/10I结晶速率加快,可在较低的降温速率下获得较高的相对结晶度;通过Kissinger理论得到PA10T/10I非等温结晶活化能绝对值随着PA10I单元含量增加逐渐减小,结晶变得较为容易。

High temperature copolyamide PA10T/10Iwas prepared by melt polycondensation method using decanediamine,terephthalic acid and isophthalic acid as raw materials,and isothermal crystallization kinetics of PA10T/10Iwith different ratios were obtained by differential scanning calorimetry(DSC).The results shown that with the increase of the proportion of 10Iunits,the crystallization peak temperature of PA10T/10Idecreased gradually,the crystallization time decreased,and the relative crystallinity increased.As the rate of cooling increased,the initial crystallization temperature of PA10T/10Idecreased,and the time required for the polymer to reach the same relative crystallinity decreased.The nucleation of PA10T/10I may contain homogeneous nucleation and heterogeneous nucleation by Jeziorny method.After the proportion of 10Iunits exceeded 5%,crystal growth rate was faster in the early stage of crystallization,and the crystal growth space was reduced and the growth was transform to low dimensional;by the Mo method,it was found that with the increase of relative crystallinity,F(T)increased gradually,and the rate of cooling increased.As the proportion of 10Iunits increased,the value ofαgradually increased within a certain range.Kissinger theory obtained that the absolute value of its non-isothermal crystallization activation energy decreased with the increase of 10Iproportion,and the crystallization rate increased.