PMDA/ODA型聚酰亚胺薄膜的热氧化降解动力学研究  

Thermo-oxidative Degradation Kinetics of PMDA/ODA-type Polyimide Film

作　　者：刘仪 许晓洲 莫松[2] 韩刚 朱才镇 李翠华 范琳[2,3] Yi Liu;Xiao-zhou Xu;Song Mo;Gang Han;Cai-zhen Zhu;Cui-hua Li;Lin Fan(College of Chemistry and Environmental Engineering,Shenzhen University,Shenzhen 518060;Laboratory of Advanced Polymer Materials,Institute of Chemisty,Chinese Academy of Sciences,Beijing 100190;School of Chemical Sciences,Unversity of Chinese Academy of Scineces,Beijing 100049)

机构地区：[1]深圳大学化学与环境工程学院,深圳518060 [2]中国科学院化学研究所,北京100190 [3]中国科学院大学化学科学学院,北京100049

出　　处：《高分子学报》2020年第10期1169-1177,I0005,共10页Acta Polymerica Sinica

摘　　要：聚酰亚胺薄膜热氧化降解为多步反应过程,仅通过单一动力学三要素(表观降解活化能E、反应模型f(α)以及指前因子A)无法充分反映其降解行为特性.本研究基于均苯四甲酸二酐/4,4'-二氨基二苯醚(PMDA/ODA)型聚酰亚胺薄膜线性升温条件下的热氧化失重微分曲线,采用Fraser-Suzuki方程进行分峰拟合,将降解过程中每个反应步骤对应的失重行为区分开来,而后通过Friedman方法以及Master-plots理论对每个反应过程单独进行动力学分析,确定相应的E,f(α),以及A值.动力学分析结果表明聚酰亚胺薄膜热氧化降解过程包含2个主反应,两者的E值分别为154.00和139.27 kJ/mol,lnA值分别为18.55和16.74 s−1,且这2个主反应均符合理论Avrami-Erofeev模型.在此基础上,通过以上动力学参数重建并预测了动力学分析过程中所采用的升温程序以内以及之外的热失重曲线,验证了动力学参数的有效性.Polyimide films have been successfully applied as cable insulation layer,optical fiber coating,printed circuit board and flexible solar cell substrates,owing to their excellent heat resistance and mechanical properties.During the devices fabrication and application,the polyimide films are usually exposed to elevated temperature or thermal oxidation environment,which often causes material degradation and results in device failure.Therefore,it is necessary to understand the thermo-oxidative degradation behavior of polyimide films in order to improve the reliability of the materials.The thermo-oxidative degradation of polyimide film was a multi-step process.It can not be described by one kinetic triplet,i.e.,the apparent activation energy E,reaction model f(α)and preexponential factor A.In this study,the multi-step thermo-oxidative degradation of polyimide film derived from PMDA and ODA was investigated based on its thermogravimetirc curves under different linear heating rates.The overlapped processes incorporated in the overall thermo-oxidative degradation were firstly separated by peakfitting of the differential thermogravimetric curves of polyimide film using Fraser-Suzuki function.Kinetic analysis of each separated process was subsequently conducted by employing Friedman method and Master-plots to determine the E,f(α)and A.The kinetic result revealed that two overlapped processes were involved in the overall thermo-oxidative degradation of polyimide film.The E values for the two processes were 154.00 and 139.27 kJ/mol respectively.The corresponding lnA values were 18.55 and 16.74 s−1.Both the two processes followed the Avrami-Erofeev model.Moreover,the validity of these kinetic parameters obtained were verified by reconstruction of original TGA curves and prediction of TGA curve not employed in the kinetic analysis.

关 键 词：聚酰亚胺薄膜 热氧化降解 多步反应过程 动力学 预测 

分 类 号：TQ323.7[化学工程—合成树脂塑料工业] TB383[一般工业技术—材料科学与工程]