| abstract |
A water redispersible polymer powder is produced by drying an aqueous mixture of a thermosettable epoxy resin having a glass transition temperature (Tg) of less than 50 °C, a colloidal stabilizer capable of dispersing the epoxy resin at a temperature above the Tg of the epoxy resin, preferably a polyvinyl alcohol, in an amount of the colloidal stabilizer of at least 2% by weight, and an interfacial crosslinking agent, such as a water soluble amino acid or a water soluble polyfunctional acid, such as polyacrylic acid, in an amount of at least 0.1% by weight, each based upon the weight of the thermosettable epoxy resin. The RDP may optionally include a hardener or curing agent, and may be hardened, cured, or crosslinked by cement ingredients when admixed with water. The water redispersible polymer powder exhibits unexpectedly superior redispersibility and good stability in cementitious formulations. |