Binks Bernard P, Duncumb Benjamin, Murakami Ryo
Surfactant & Colloid Group, Department of Chemistry, University of Hull, Hull, UK.
Langmuir. 2007 Aug 28;23(18):9143-6. doi: 10.1021/la701393w. Epub 2007 Aug 7.
The effect of pH and salt concentration on the phase inversion of silica particle-stabilized foams is presented. Inversion from a water-in-air powder to an air-in-water foam can be achieved by increasing the pH of the aqueous phase. By contrast, an increase in the salt concentration causes a nonfoaming aqueous dispersion to foam. The results are rationalized in terms of changes in the hydrophobicity of the solid surfaces, probed by measurement of the contact angles of water drops on hydrophobized glass slides in air.
本文介绍了pH值和盐浓度对二氧化硅颗粒稳定泡沫相转变的影响。通过提高水相的pH值,可以实现从空气包水粉末到水包空气泡沫的转变。相比之下,盐浓度的增加会导致非发泡水分散体产生泡沫。通过测量空气中疏水化载玻片上水滴的接触角来探测固体表面疏水性的变化,从而对这些结果进行了合理的解释。