【摘要】 将甲基丙烯酸甲酯(MMA)与SBS接枝共聚制得SBS-g-MMA接枝共聚物.利用热分析法研究了该共聚物在升温速率为10 K.min-1的N2气、O2气气氛中的热降解过程与热降解动力学.确定了SBS-g-MMA在N2气气氛下的热降解过程分2步完成,第1步热降解温度为530~720 K,第2步热降解温度为720~830 K;在O2气气氛下的热降解过程分3步完成,第1步热降解温度为477~597 K,第2步热降解温度为597~714 K,第3步热降解温度为714~774 K.在N2气气氛下的热降解过程的平均活化能Ea=376.27 kJ.mol-1,微分机理函数f(α)=(1-α)[-ln(1-α)]-2/3,指前因子lnA=73.029,积分机理函数g(α)=[-ln(1-α)]3,指前因子lnA=64.220;在O2气气氛下的热降解过程较为复杂,实验结果不明确.更多还原

【Abstract】 The SBS-g-MMA was synthesized based on styrene-butadiene-styrene block polymer(SBS) and methyl methacrylate(MMA).Under oxygen and nitrogen atmosphere condition,SBS-g-MMA thermal degradation process has been studied by using thermal analysis method.The results indicated that the SBS-g-MMA degradation included two steps under nitrogen atmosphere,the thermal degradation temperature approximately is 530~720 K in the first step and the second step is 720~830 K.The SBS-g-MMA degradation included three steps under oxygen atmosphere,the first step of thermal degradation temperature approximately is 477~597 K,the second step is 597~714 K and the third step is 714~774 K.By Comparison of the 39 species common mechanism function with Achar’s method and Coats-redfern’s method,it was obtained that average activation energy of the first step under nitrogen was 376.27 kJ/mol,the total mark function of the thermal degradation mechanism was g(a)=[-ln(1-α)]3,and frequency factor lnA=64.220.The differential function of the thermal degradation mechanism was f(a) =(1-α)[-ln(1-α)]-2/3,and frequency factor lnA=73.029.The thermal degradation process under O2 atmosphere was more complicated with little results.更多还原