Polyvinyl alcohol

Polyvinyl alcohol (PVOH, PVA, or PVAl) is a water-soluble synthetic polymer. It has the idealized formula [CH2CH(OH)]n. It is used in papermaking, textile warp sizing, as a thickener and emulsion stabilizer in polyvinyl acetate (PVAc) adhesive formulations, in a variety of coatings, and 3D printing. It is colourless (white) and odorless. It is commonly supplied as beads or as solutions in water. Without an externally added crosslinking agent, PVA solution can be gelled through repeated freezing-thawing, yielding highly strong, ultrapure, biocompatible hydrogels which have been used for a variety of applications, such as vascular stents, cartilages, contact lenses, etc. Although polyvinyl alcohol is often referred to by the acronym PVA, more generally PVA refers to polyvinyl acetate, which is commonly used as a wood adhesive and sealer.