Air Entraining Concrete Admixture
This information reflects our best understanding of product composition in 2022.
Air entraining admixtures are surfactants that are added to concrete in order to increase the volume of entrapped air. They are specified under ASTM C260/C260M and can be used in normal and lightweight concrete. Air entraining admixtures contain...
Air entraining admixtures are surfactants that are added to concrete in order to increase the volume of entrapped air. They are specified under ASTM C260/C260M and can be used in normal and lightweight concrete. Air entraining admixtures contain surfactants with hydrophobic and hydrophillic ends. When added to cement they align at the air-water interface and form stable bubbles increasing the volume of entrapped air from less than 3% to between 4 and 8% by volume. This entrapped air improves the concrete's freeze-thaw resistance. Air entrainers include chemicals derived from natural wood resins, tall oil, and fatty acids. They may also be based on synthetic chemicals such as sulfonated hydrocarbons and alcohol ethoxylates. Anionic surfactants drived from wood resins were found to be most common. Air entrainers can be used with other admixtures, but some additives and admixtures, such as superplasticizers and fly ash, can inhibit their functionality.