尼龙69的热降解过程与动力学研究

STUDY ON PROCESS AND KINETICS OF THERMAL DEGRADATION IN NYLON 69

利用ＴＧ－ＤＴＧ－ＤＴＡ方法研究了尼龙６９在空气和Ｎ２气氛中以不同升温速率β时的热降解过程和动力学，实验发现，尼龙６９在空气中的热降解过程为两步反应，在Ｎ２中为一步反应；随着β的增大，其降解温度线性升高。在Ｎ２气氛中的降解率和热降解温度均比空气中的高，结合反应热效应，探讨了反应机理；用Ｃｏａｔｓ－Ｒｅｄｆｅｒｎ法进行了动力学处理，确定了尼龙６９在空气中两步反应的表观反应级数分别为０和２，反应活化能为１３５ＫＪ／ｍｏｌ和５１０ｋＪ／ｍｏｌ。

At different heating rates (β) ,the thermal degradation process of nylon 69 is one step reaction in N2 and two in air through the TG-DTG investigation.The degradation temperatures rise linearly with the increasing of theβ.The degradation degree and the degradation temperatures in N2 are higher than those in air. The possible degradation mechanism of nylon 69 has been discussed according to the heating effect of the reaction .The parameters of thermal degradation kinetics of nylon 69 have been obtained by coats-Redfern mehthod ,the apparent reaction order of two step reactions in air are 0 and 2 , the reactive energies are 130 kJ/mol and 510 kJ /mol.