Effects of oxyethylene groups on the adsorption behavior and application performance of long alkyl chain phosphate surfactants

Alcohol ether-derived surfactants have caused extensive research in the past period. Alcohol ether phosphate is one of them. However, detailed information about long alkyl chain phosphates (LAPs) is rarely reported in the previous literature. To bridge this gap, in this paper, LAPs with different oxyethylene (EO) addition numbers are used as the research objects. The influence of EO chain length on the adsorption behavior of LAPs is explored through static surface tension, dynamic surface tension and dynamic contact angle. The results indicate that the LAPs that contain no EO group or with fewer EO groups have very low surface tension reduction efficiency and kinetic surface activity, but it can be significantly improved by introducing longer EO chains. The adsorption process of LAP samples with faster adsorption rate on the gas-liquid surface is the mixed diffusion-kinetic mechanism. It has the fastest adsorption rate when the EO addition number is 9. In addition, the wetting, permeability, emulsification, and foam stability of LAPs can be significantly improved by introducing a longer EO chain, but the antistatic property is better when the EO chain is shorter. (C) 2021 Elsevier B.V. All rights reserved.