Al(OH)3对聚丙烯腈粉火焰传播特性影响研究

为研究Al(OH)₃粉体抑爆剂对聚丙烯腈（polyacrylonitrile, PAN）粉尘爆炸的抑制作用，利用透明管道爆炸传播测试系统，研究不同含量的Al(OH)₃对PAN粉尘爆炸火焰传播形态、温度等参数的影响，并采用扫描电镜、热重分析仪、傅里叶红外光谱仪研究Al(OH)₃抑制PAN粉尘爆炸的微观特征，总结出Al(OH)₃对PAN粉尘爆炸的抑制机理。测试结果表明，随着Al(OH)₃质量分数的增加，PAN粉尘爆燃的最大火焰传播距离和传播速度逐渐减小。同时压力监控及温度监控结果显示，随着Al(OH)₃质量分数的增加，PAN粉尘的最大爆炸压力及最大温度均逐渐减小，由此验证了Al(OH)₃对PAN粉尘爆炸的抑制作用，且60%质量比的Al(OH)₃的抑制效果最好。通过对PAN粉尘爆炸固态产物表征及热分析的研究，从物理和化学两个方面分析了Al(OH)₃对PAN粉尘火焰的抑制机理，物理抑制包括包覆、吸热降温、气体惰化3种方式，化学抑制主要通过消耗维持燃烧爆炸连锁反应的关键自由基?O和?OH减少了自由基?H、?OH与?O之间的放热反应。

Study on the effect of Al(OH)3 on the flame propagation characteristics of polyacrylonitrile powder

In order to study the inhibitory effect of Al(OH)₃ powder explosion suppressant on polyacrylonitrile (PAN) powder explosion, a transparent pipeline explosion propagation test system was used to study the influence of mass fractions of Al(OH)₃ on the flame propagation shape, temperature and other parameters of PAN powder explosion. The scanning electron microscope, thermogravimetric analyzer and Fourier infrared spectrometer were used to study the microscopic characteristics of Al(OH)₃ inhibiting PAN powder explosion, and the mechanism of Al(OH)₃ inhibiting PAN powder explosion was summarized. The results show that the maximum flame propagation distance and the velocity of PAN powder deflagration gradually decrease with the increase of the mass fraction of Al(OH)₃. At the same time, pressure monitoring and temperature monitoring showed that with the increase of the mass fraction of Al(OH)₃, the maximum explosion pressure and maximum temperature of PAN powder gradually decrease. Thus, the inhibition effect of Al(OH)₃ on PAN powder explosion was verified, and the inhibition effect of Al(OH)₃ at mass ratio of 60% was the best. Through the study of characterization and thermal analysis of PAN powder explosion solid products, the inhibition mechanism of PAN powder flame by Al(OH)₃ was analyzed from both physical and chemical aspects. Physical suppression includes coating, endothermic cooling, and gas inerting. Chemical suppression is mainly by reducing the exothermic reaction between free radicals ?H, ?OH and ?O through consuming the key free radicals O? and OH? that maintain the chain reaction of combustion and explosion.