SIS—g—AA热降解动力学研究

用热重分析（TG）和微分热重分析（DTG）研究了SIS-g-AA的热降解动力学。结果表明,该共聚物在N2气氛中的热降解分2步完成：第1步的热降解温度为553～703K;第2步的热降解温度为703～873K。用Achar方程和Coats-Redfern方程对常见的机理函数进行计算比较,得到第1步热降解平均活化能Ea=177.43kJ/mol,热降解的积分机理函数g（α）=（1-α）-1-1,频率因子lnA=27.48;热降解的微分机理函数f（α）=（1-α）2,频率因子lnA=34.05。在O2气氛中的降解分5步完成：第1步的热降解温度为448～543K,第2步的热降解温度为543～577K,第3步的热降解温度为577～640K,第4步的热降解温度为640～696K,第5步热降解温度为696～767K。用Achar方程和Coats-Redfern方程对40种常见的机理函数进行计算比较,得到第2步热降解平均活化能Ea=206.82kJ/mol,热降解的积分机理函数g（a）=（1-α）-1/3-1]2,频率因子lnA=35.16;热降解的微分机理函数f（α）=3（1-α）4/3（1-α）-1/3-1]-1/2,频率因子InA=41．79。

Study on thermal degradation kinetics of SIS-g-AA under N2and N2 atmosphere

Under oxygen and nitrogen atmosphere condition, SIS-g-AA thermal degradation process has been studied using thermal analysis method. The results indicated the SIS-g-AA degradation included two steps under nitrogen atmosphere condition, the first step of thermal degradation tem- perature approximately is 553-703 K, the second step of thermal degradation temperature approximately is 703-873 K; The SIS-g-AA degradation included five steps Under oxygen atmosphere condition, the first step of thermal degradation temperature approximately is 448-543 K, the second is 543-577 K, the third is 577-640 K, the fourth is 640-696 K, the fifth is 696-767 K. Compared with the common mechanism function with Achar and Coats-redfern method, the average activation energy of the first step under nitrogen was 177. 43 kJ/mol, the integral function of the thermal degradation mechanism was g（a）= （1-a）-1-1, frequency factor lnA was27. 48, the differential function of the thermal degradation mechanism was f（a）= （1-a）z and frequency factor lnA was 34. 05. The results also indicated that the average activation energy of the second step under oxygen was 206.82 kJ/mol, the integral function of the thermal degradation mechanism was g（a）= （1-a）^-1/3-1]^2, frequency factor lnA was 35.16, the differential function of the thermal degradation mechanism was f（a） = 3（1-a）^4/3 （1-a）^-1/3-1-]^-1/2, and frequency factor lnA was 41.79.