氧化铝/聚四氟乙烯热化学反应特性及影响因素

In order to explore the pre-ignition reaction of aluminum/polytetrafluoroethylene (AI/PTFE) material. AI₂O₃/PTFE composites were prepared by ultrasonic mixing method. The crystal structure, microstructure and thermochemical properties were characterized and the thermochemical reaction characteristics and influencing factors were analyzed. The results show that AI₂O₃ can delay the initial temperature of PTFE melting. The smaller the particle size of AI₂O₃ and PTFE, the easier it is for the AI₂O₃/PTFE material to react and release more heat. AI₂O₃ with small particle size can delay the initial temperature of AIF₃ formation reaction and advance the initial temperature of AIF₃ crystal transformation reaction, thus increasing the concentrated heat release of the reaction. The reaction degree of AI₂O₃ (50nm) and PTFE (1 μm) is the highest. The thermochemical reaction properties of α-AI₂O₃/PTFE are better than those of γ-AI2O3/PTFE and amorphous AI₂O₃/PTFE. The thermochemical reaction of AI₂O₃/PTFE exhibits the typical kinetic characteristics. With the increase of the heating rate, the peak temperature of the main heat release peak of the reaction increases. The calculated apparent activation energy of AI₂O₃/PTFE reaction is 45.0kJ/mol.