Study on the Influence of Different Surfactants on Cement Particles.

The cementitious foam material is the key technology to prevent coal spontaneous combustion, but the mechanism of different surfactants on cement particles is not clear. In this paper, four surfactants, anionic, cationic, and nonionic, were screened out by foam index. The adsorption characteristics of different surfactants and cement particles were analyzed by surface tension test, zeta potential test, Fourier infrared spectrum test, and contact angle test. The research results show that the surface tension and critical micelle concentration (CMC*) of ionic surfactants are greatly affected by cement pore solutions, while nonionic surfactants have little effect on the zeta potential of cement particles. The adsorption capacity of cement particles for the four surfactants is SDS > AES > TTAB > TX-100. The maximum contact angles of anionic surfactants SDS and AES are 69 and 50°, respectively. When the concentration of surfactants is less than CMC*, the yield stress of cement slurry increases with the increase in concentration. Based on the experimental results, the adsorption model of cement particles and surfactant molecules was constructed, which filled the research gap of the adsorption mechanism of surfactant and cement particles, and provided an important theoretical guarantee for the follow-up research and development of new cement-based foam materials and engineering applications.