Defoamers
Defoamers are additives used in concrete mixtures to eliminate or reduce foam formation during mixing. Foam can occur in concrete mixtures due to air-entraining agents, high-speed mixing, or other factors. During concrete mixing, air can become trapped, forming bubbles or foam. This can weaken the concrete and reduce its strength and durability. Excessive foam or bubbles can make the concrete challenging to handle and apply.
Defoamer additives such as TBP are added to the concrete mixture to prevent these issues. These additives work by reducing the surface tension of the concrete, which helps to break down the bubbles and prevent them from forming. This allows for a smoother and more consistent mixture. The use of defoamers can help to ensure consistent and uniform concrete mixtures and can improve the performance and quality of the finished concrete.
Defoamer additives such as TBP (Tributyl phosphate) prevent the formation of excessive foam or bubbles during mixing. Typical addition to the concrete mixture is at a rate of 0.1% to 0.3% by weight of cement. The exact amount of defoamer needed will depend on factors such as the specific type of concrete being used, the mixing process, and the desired final properties of the concrete.