SOLID SILICONE DEFOAMING AGENT AND METHOD FOR ITS PRODUCTION

摘要

A solid defoaming composition, and a process for making the composition, is described. The defoaming composition comprises a solid nonionic surfactant, selected from aliphatic esters of glycerol and propylene glycol; a solid, water-soluble polymer, selected from carboxyvinyl polymers and poly(vinyl alcohol)s; and a silicone composition, composed of a fine silica powder and a silicone oil having a viscosity of at least 100 cS at 25 DEG C. A molded cake of the composition of this invention does not bleed silicone oil and may be employed to defoam aqueous systems for extended periods without the need to replenish the active ingredient. The composition is particularly useful for defoaming septic tanks and sewage.