Defoamers & Antifoams

Less Bubbles with Chemical Precision

Silica solutions for liquid defoamer formulations

Oil-based liquid defoamers are required in numerous industries, both for disruption-free production processes and for the properties and quality of the end products. Defoamers work by forcing oil droplets into the water-air boundary layer of a foam lamella, where they spread and destroy the lamella. But oils are generally not sufficiently effective on their own.

Silica from Evonik is a highly effective additive for liquid defoamer formulations. Adding hydrophobic SIPERNAT® or AEROSIL® silica boosts the ability to fight foam, because the oil droplets can penetrate the boundary layer much quicker. This allows for a reduction of oil content in the formulation and economical dosing of defoamers during application.

Most hydrophobic SIPERNAT® and AEROSIL® products are suitable for defoamer products used in food contact applications.

Moreover, hydrophilic silica products act as anti-settling agent and rheology controller in oily media, such as mineral oil, silicone oil or vegetable oil.

Defoamer use cases:

  • Paints & Coatings: Liquid defoamers are added to paints and coatings to ensure bubble-free application without pit holes which are an unacceptable defect in automotive coatings and architectural paints.
  • Paper: In paper production, defoamers are indispensable during processing and for the quality of paper products. Without highly efficient defoamers, an enormous amount of foam would build up when washing the pulp, which would impair the manufacturing process, reduce productivity and cause plant downtime.
  • Textile: In textile processing, defoamers are needed for dyeing and washing fabrics and garments.
  • Agriculture: In liquid agrochemicals such as pesticides, herbicides and fungicides, defoamers prevent foaming both during production and handling, for example filling tanks and spraying.
  • Environment: Defoamers are required for water purification, for example in wastewater treatment plants, where foam is caused by organic residues. Special defoamer formulations with oil and surfactants are used here. 

AEROSIL®

SIPERNAT®

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