Base-mediated hydrophobing compositions and processes

摘要

Water-resistant gypsum boards and compositions and methods for their manufacture are provided. The methods include forming a mixture of water, hydroxide, and siliconate, adding siloxane to the mixture, adding calcium sulfate hemi-hydrate to the mixture to form an aqueous slurry, curing the aqueous slurry under heat, drying the aqueous slurry, and forming a water-resistant gypsum board.