高流动性聚酰胺6的热降解研究
Study on Thermal Degradation of High Flow Polyamide 6
黄逸伦 1赵嘉玮 1王兴国 1初立秋 1高达利 1吴长江1
作者信息
- 1. 中石化(北京)化工研究院有限公司,北京,100013
- 折叠
摘要
采用热重分析法研究了高流动性聚酰胺 6(PA6)在氮气(N2)和氧气(O2)氛围中的热降解动力学,确定了其热降解机理类型.结果表明:不同升温速率下,PA6 在 N2 中的热降解过程为一步反应,在 O2 中为二步反应.高温环境中聚合物在O2 中的初始降解温度、最大失重速率温度和终止降解温度均低于无氧环境,并且这些特征降解温度在 N2 和 O2 氛围中均随升温速率的提高而升高.通过 Flynn-Wall-Ozawa(FWO)、Kissinger-Akahira-Sunose(KAS)和 Tang 3 种拟合方法确定了PA6 在N2 和O2 中的平均热降解活化能分别为 258.22 kJ/mol和 224.36 kJ/mol,并通过与Coats-Redfern法计算得到不同机理函数时的活化能对比,确定了PA6 在 N2 和 O2 中的热降解机理函数类型为随机成核后生长的三级减速型(F3 型).
Abstract
The thermal degradation kinetics of high flow polyamide 6(PA6)in nitrogen(N2)and oxygen(O2)atmospheres were studied using thermogravimetric analysis,and the type of thermal degradation mechanism was determined.The results show that the thermal degradation process of PA6 in N2 at different heating rates is a one-step reaction,while it is a two-step reaction in O2.In the high-temperature environment,the polymer exhibits lower initial degradation temperature,maximum weight loss rate temperature,and termination degradation temperature in O2 atmospheres compared to an O2 free environment.In the meanwhile,these characteristic degradation temperatures increase with the increase of the heating rates in N2 and O2 atmospheres.The average thermal degradation activation energies of PA6 in N2 and O2 are determined to be 258.22 kJ/mol and 224.36 kJ/mol respectively,by using three fitting methods:Flynn-Wall-Ozawa(FWO),Kissinger-Akahira-Sunose(KAS),and Tang method.By comparing the activation energies calculated with the Coats-Redfern method for different mechanism functions,it is determined that the thermal degradation mechanism function type of PA6 in N2 and O2 is the third-order deceleration type after random nucleation growth(F3 type).
关键词
聚酰胺6/热降解/活化能/动力学Key words
polyamide 6/thermal degradation/activation energy/kinetics引用本文复制引用
出版年
2024
NETL
NSTL
万方数据