Читать книгу Additives for Waterborne Coatings - et al. - Страница 81

The main defoamers for styrene acrylic emulsions have moderate to very strong hydrophobicity. Grades suitable for acrylic emulsions are often less effective in defoaming styrene acrylic emulsions. Depending on the area of application, defoamers with different chemistries are used. Widely used defoamers for architectural coatings are mineral oils, natural or synthetic oils or polysiloxanes. For applications with low PVC more compatible, grades, such as modified siloxanes or silicone-free polymers, are preferred.