Title: Nonionic Surfactants as Bubble Stabilizer in Concrete

Author(s): Min Qiao, Guangcheng Shan, Jian Chen, Navnxiao Gao, Qianping Ran

Publication: Symposium Paper

Volume: 354

Issue:

Appears on pages(s): 387-394

Keywords: air entraining; bubble stabilizer; concrete; nonionic surfactants

DOI: 10.14359/51736091

Date: 7/1/2022

Abstract:
Entraining tiny and stable bubbles into cementations mixtures and concrete is becoming more and more important with the complex composition of cement and concrete. Surfactants as air-entraining agents are important concrete admixtures that intentionally create a number of functional air voids in concrete. In this study, nonionic surfactants appear to be a stabilizing agent for ionic surfactants to improve the bubble stability in fresh concrete. The surface tensions and foam properties of their solutions, and the air contents and bubble size distribution of the fresh cement mortars were determined. The results show that nonionic surfactants are introduced into the interface for co-assembly, the electrostatic repulsion between ionic surfactant molecules is effectively diminished and making the arrangement on the interface more stable. The blend of nonionic and ionic surfactants induced smaller bubble formation in aqueous solutions, which also have increased bubble stability in cement mortars. So, it is of great practical significance to blend nonionic and ionic surfactants to improve the air-void stability in concrete.