火场中油漆稀料与载体热分析动力学研究

The study of kinetics mechanism on paint thinner with matrix in fire scene

对不同气氛、不同升温速率下的油漆稀料与载体的混合样品进行热重分析,并采用Coats-Redfern法对样品进行热动力学分析,推断反应机制。研究发现:氮气气氛下,油漆稀料的加入会使混合样品的活化能增加,预热阶段反应机理由幂指数机制向随机成核及增长或化学反应机制转变,30K/min升温速率下热解阶段反应机制向三维扩散机制转变;空气气氛下,低速升温时油漆稀料的加入使第一阶段变为化学反应机制,第二阶段为相界反应机制,高速升温则会使第一阶段转变为随机成核及增长机制,其他基本不变。

Thermogravimetric analysis of mixed samples of paint thinner and carrier under different atmospheres and different heating rates was carried out, the kinetic analysis of mixed sample was carried out too and the mechanism was inferred of them with the method of Coats- Redfern method. The study exhibited that:In the nitrogen atmosphere,the addition of paint thinner will increase the activation energy of the mixed sample. The preheating stage’s reac? tion mechanism is changed from power exponent mechanism to random nucleation and growth mechanism or chemical reaction mechanism, and the reaction mechanism in the pyrolysis stage shifts to the three-dimensional diffusion mechanism when the heating rate is 30 K/min.In the air atmosphere, when the heating rate is small, on account of additive, the reaction mechanism in the stage one of the pyrolysis processis converted into a chemical reaction mechanism, and stage two is phase boundary reaction mechanism, while when the heating rate is big,the reaction mechanism in the stage one is changed to a random nucleation growth mechanism, with others remain the same.