有机硅橡胶SD-33粘结剂的热分解动力学研究

Study on Thermal Decomposition Kinetics of Polydimethylsiloxane Rubber SD-33 Bonder

根据SD-33粘结剂在升温速率分别为5、10、20K／min时的DSC—TG曲线，在20～550℃温度范围对SD-33粘结剂的热分解过程进行了研究，用Coats-Redfern方法获得SD-33粘结剂的热分解动力学参数和机理函数。结果表明，在不同升温速率的TG曲线上，SD-33粘结剂热失重开始温度大致相同，而热失重结束温度随升温速率的增大而升高。同时，在升温速率为5K／min的DSC曲线上SD-33粘结剂从450．6℃开始分解放热，峰顶温度为456．6℃，结束温度为506．3℃，放热量为17．91J／g。在320℃温度以下SD-33粘结剂具有良好的热稳定性。SD-33粘结剂热分解的活化能为154．91kJ／mol，指前因子为5．097×10^10s^-1，机理函数为，（α）=（1-α）^2。

The thermal decomposition process of SD-33 bonder is studied by the DSC-TG curves with the rate of heating being 5 K/min, 10 K/min, and 20 K/min respectively and the temperature range of 20-550℃, the thermal decomposition kinetics parameter and the mechanism function of SD-33 bonder are obtained by CoatsRedfern method. The results show that the initial temperatures of SD-33 bonder are approximately same, the final temperatures increase with the increasing heating rate of TG curves. At one time, the initial decomposition temperature of SD-33 bonder ：s 450.6℃, the top temperature is 456.6℃ and the enthalpy is 17.91 J/g on DSC curve having a rate of 5 K/min. The SD-33 bonder has good thermal stability when the temperature is lower than 320℃. The thermal decomposition activation energy of the SD-33 bonder is 154.91KJ/mol, the pre-exponential factor is 5. 097 X 101~s-1, and the mechanism function is f（α） = （1 -α）^2.