AP-PFPE-Al复合粒子的能量及稳定性研究

Energy and Stability Research of AP-PFPE-Al Composite Particles

采用含氟聚醚(PFPE)为功能层包覆球形铝粉,并通过一步沉积法制备了AP-PFPE-Al复合粒子。通过扫描电子显微镜、激光粒度仪表征了复合粒子的表观形貌及粒度分布,同时通过氧弹量热仪、摩擦感度仪和差热分析仪分析了复合粒子的燃烧热、摩擦感度及热稳定性。结果表明:随着PFPE的加入,AP-PFPE-Al复合粒子表面沉积铝粉粒子减少,粒径分布更集中,表明PFPE可明显改善AP对铝粉的包覆效果;与AP-Al机械混合相比,AP-PFPE-Al复合粒子的燃烧热提高近50%,摩擦感度降低40%以上,低温分解峰延后近20℃,热分解表观活化能Ea、热爆炸临界温度Tb分别提高6.13 kJ·mol^(-1)和20.6℃,表明复合粒子能量水平更高,稳定性更好。

Fluoropolyether was used as the functional layer to coat spherical aluminum powder,and AP-PFPE-Al composite particles were prepared by one-step deposition method.The apparent morphology and particle size distribution of composite particles were characterized by scanning electron microscope and laser particle size analyzer,at the same time,the heat of combustion,friction sensitivity and thermal stability of the composite particles were analyzed by the oxygen-nitrogen calorimeter,friction sensitivity meter and differential thermal analyzer.It is found that with the adding of PFPE,less aluminum particles are deposited on the surface of AP-PFPE-Al composite particles and particle size distribution is more concentrated,which show PFPE can significantly improve the coating effect of AP on aluminum powder.Compared with AP-Al mechanical mixture,the heat of combustion of AP-PFPE-Al composite particles is increased by nearly 50%,the friction sensitivity is reduced by more than 40%,the low-temperature decomposition peak is delayed by nearly 20℃,the apparent activation energy and thermal explosion critical temperature is 6.136 kJ·mol^(-1) and 20.6℃higher,which show the composite particles have higher energy level and better thermal stability.