弱氧条件下橡胶的燃烧机理

Combustion of Tyre Components at Low Oxygen Concentration

:应用 TGA/FTIR研究了橡胶的三种单体 :天然橡胶 (Nr)、丁苯橡胶 (Sbr)和顺丁橡胶 (Br)在 N2 和 O2 的体积分数为 2 %的气氛中的燃烧特性。橡胶单体的热解可分为 2～ 3个阶段 ,其中 Sbr的初始失重温度和 Nr完全失重的温度最低 ;在失重过程中析出气体的燃烧和橡胶热解相对量的变化引起吸热与放热现象的交替变化 ;热解与燃烧产物主要为 CO、CO2 和 CHn,它们的生成速率随升温速率的升高而增加 ,其总量保持不变。最后应用 Phadin提出的方法计算了动力学参数和确定了反应机理 。

The principles of coal combustion of the tyre components styrene butadiene rubber (Sbr),natural rubber (Nr) and polybutadiene rubber (Br) were investigated in a TGA/FTIR analyzer under nitrogen and 2 percent of oxygen atmosphere at various heating rates.The tyre samples showed two to three distinct areas of weight loss,representing a lower and a higher temperature of decomposition.The components of the lowest temperatures of initial weight loss and fully decomposed are Sbr and Nr,respectively.The exothermal and endothermal reactions varied with the temperature due to the rate of evolution and the combustion of volatile gases.The gases were identified as CO,CO 2 and CH n,in which the evolution rate increased with the heating rate enhanced.The Phadins approach was used to calculated the kinetic parmeters and determine the mechanism of the combustion of the tyre components.It shows the combustion of the components under low oxygen concentration was controlled by gas dispersion.