首次采用积分-微分相结合的方法研究了聚苯乙烯非等温热解动力学.通过比较同一机理函数的微分:和积分法结果,推测了聚苯乙烯热解所遵循的机理及动力学参数。实验结果显示,在氮气中聚苯乙烯有一个失重阶段,温度范围282.9℃~398.2℃,在此范围内约有96%聚苯乙烯发生了分解.其最大失重速率发生在372.4℃。积分一微分法拟合结果表明.聚苯乙烯在氮气中的热解符合一级化学反应.其动力学模型方程式为:da/dt=Aexp(-E/R71)(1-α)。平均表观活化能E为199.2kJ/mol.lnA为36.56。
The kinetic process of polystyrene degradation was first studied by combining the non-isothermal differential and integral methods. The experiment results indicate that there has a mass loss stage for polystyrene degradation in N2. The temperature range is from 282.9 ℃ to 398.2 ℃,and the maximum weight-loss rate is achieved at 372.4 ℃. Kinetic analysis results indicate the associated kinetic mechanism is first order chemical reaction: da/dt=Ae^(-E/RT)(1-α). The average activation energy E is 199.2 kJ/mol and lnA is 36.56.