Polyvinyl acetate
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Polyvinyl acetate (PVA or PVAc) is a rubbery synthetic polymer. It is prepared by polymerization of vinyl acetate monomer, also referred to as VAM. Partial or complete hydrolysis of the polymer is used to prepare polyvinyl alcohol. Hydroylized alcohol product is typically in the 87% to 99% range (converted PVA). It was discovered in Germany by Dr. Fritz Klatte in 1912.
As an emulsion in water, PVA is sold as an adhesive for porous materials, particularly wood, paper, and cloth. It is the most commonly used wood glue, both as "white glue" and the yellow "carpenter's glue." PVA is widely used in bookbinding and book arts due to its flexibility, and because it is non-acidic, unlike many other polymers. Elmer's Glue is a popular brand of white PVA glue sold in the United States.
PVA is a common copolymer with more expensive acrylics, used extensively in paper, paint and industrial coatings, referred to as vinyl acrylics. It can also be used to protect cheese from fungi and humidity[citation needed]. It is slowly attacked by alkali, forming acetic acid as a hydrolysis product. Boron compounds like boric acid or borax will form tackifying precipitates by causing the polymer to cross-link.
PVA is also commonly recommended for use in making leather handcrafted works and papier-mâché.