Abstract: The surface of commercial silicon dioxide particles was hydrophobically modified in this paper. The aqueous foams were prepared by stirring mixtures of dodecyl sulfate sodium (SDS) and particles before or after surface modification. The hydrophobicity of particles, the particle additions, the concentration of particles adsorbed on the air/water interface and the stability of dynamic stretching liquid film were investigated. Results shows that the foamability and foam stability of the hydrophilic silica/SDS dispersion is better than that of the modified silica particle/SDS dispersion. The foam stability increases with the increase of the particle addition and it reaches a maximum with the particle addition of 0.05 wt%. However, in dynamic stretching conditions, the liquid film can be stabilized by hydrophobically modified silica particles. The stretch length of liquid film reaches maximum at the particles addition of 0.05 wt%.

Key words: foam；foam stability, silicon dioxide particles, hydrophobicity, dynamic tensile

摘要： 本文对市售二氧化硅粒子进行疏水改性，分别用改性前和改性后的二氧化硅粒子与十二烷基硫酸钠制备泡沫分散液，探讨了二氧化硅粒子亲、疏水性，粒子浓度，粒子在气/液界面膜上的吸附量以及动态拉伸条件下的液膜稳定性的变化规律。研究结果表明，在搅拌条件下，与改性后粒子相比，改性前粒子对维持泡沫体系的起泡性和稳定性作用较强。泡沫稳定性随二氧化硅粒子质量分数的增加而增大，在粒子浓度为0.05%时达到最大值。在拉伸条件下，改性后粒子对液膜稳定性的增强效果优于改性前粒子的作用。改性后二氧化硅粒子质量分数为0.05%的分散液的液膜拉伸最长。

关键词: 泡沫, 稳定性, 二氧化硅粒子, 疏水性, 拉伸