Abstract: In this study, environmentally friendly foam dispersions were prepared using twin?chain fluorocarbon surfactants (Gemini) and amphoteric hydrocarbon surfactants (LAMC) as core components. The influence of nanoscale SiO2 particles and the type of compressed gas on the foaming properties, stability, and spreading characteristics of the foam dispersion were investigated. The results revealed that nanoscale SiO2 particles exhibited molecular interactions with short?chain fluorocarbon surfactants, leading to an approximately 5.8% increase in the height of compressed nitrogen foam compared to compressed air foam when 3% nanoscale SiO2 particles were added within the experimental range. The foaming performance of the dispersion slightly decreased after the addition of 3% nanoscale SiO2 particles. However, foam stability significantly increased with the incorporation of nanoscale SiO2 particles, resulting in a 5% improvement in the stability of nitrogen foam compared to air foam. Nanoscale SiO2 particles formed a network?like structure, aggregating within the Plateau borders, effectively delaying foam drainage and coarsening, thereby enhancing foam stability. Due to the inherent differences in density and permeability of foam liquid films between nitrogen and air, the average spreading rate of compressed air foam on the oil surface increased by 2.6% compared to compressed nitrogen foam. The findings of this study provide theoretical guidance for the development and firefighting applications of environmentally friendly foam extinguishing agents containing nanoscale SiO2 particles.

Key words: short?chain fluorocarbon surfactants, hydrocarbon surfactants, nanoscale SiO2 particles, compressed gas source, foam performance