ПВА

Polyvinyl alcohol has excellent film forming, , and properties. It is also resistant to oil, grease and . It is odorless and nontoxic. It has high tensile strength and flexibility, as well as high oxygen and aroma barrier properties. However these properties are dependent on , in other words, with higher humidity more water is absorbed. The water, which acts as a plasticiser, will then reduce its tensile strength, but increase its elongation and tear strength. PVA is fully degradable and is a quick dissolver. PVA has a melting point of 230°C and 180190°C for the fully hydrolysed and partially hydrolysed grades. It decomposes rapidly above 200°C as it can undergo at high temperatures. PVA is an material but exhibits as the groups are small enough to fit into the lattice without disrupting it. Uses Preparation of is the largest use for polyvinyl alcohol in the U.S. and western Europe. Its use as a polymerization aid is the largest market in China. In Japan the major use is vinylon fiber production. Some other uses of polyvinyl alcohol include: Adhesive and thickener material in latex paints, paper coatings, hairsprays, shampoos and glues. Textile agent barrier in (PET) bottles. for use as synthetic vessels in flow testing. Movie and children's play or slime when combined with . Feminine hygiene and adult incontinence products as a plastic backing sheet. As a because materials such as do not stick to it. As a water-soluble film useful for packaging. As fiber reinforcement in concrete As a surfactant for the formation of polymer encapsulated nanobeads Used with polyvinyl acetate to make Elmer's glue Used in eye drops and hard solution as a lubricant. Used in protective chemical-resistant gloves Used as a for specimen collection, especially stool samples When doped with iodine, PVA can be used to polarize light. As an agent in medical procedures