Anionic Gemini Surfactants as Novel Air Entraining Agents

摘要

The development of high performance air entraining agents for concrete is of great importance. In this work, gemini surfactants (a new class of surfactants) have been utilized as high performance air entraining agents. Gemini surfactants modified with sulfonic groups were designed and successfully synthesized. The surface tensions and foam heights of their solutions were tested. Using them as the air entraining agents, the air contents and air-void parameters of the cement mortars were also tested. The study results clearly show that the gemini surfactants have higher surface activity, foamability, foam stability and air entraining performance compared with their single-chained cousins. The gemini surfactants had more concentrated arrangement than their single-chained cousins in gas-liquid interface, which enhanced the stability of the bubble film. The foam generated by gemini surfactants had fine bubble and high stability. So the gemini surfactants were considered as novel competent air entraining agents for concrete.