PVA-1788 and PVA-1799 are commonly used polyvinyl alcohol models in architectural coatings.
Polyvinyl alcohol is obtained by hydrolysis of polyvinyl acetate, but not by direct polymerization of vinyl alcohol. Because vinyl alcohols are so unstable, it is impossible to have free vinyl alcohol monomers. The structural formula of polyvinyl alcohol is? CH2CH? OH, in which the degree of alcoholysis and polymerization have great influence on the physical properties of pVA. The degree of polymerization of polyvinyl alcohol can be divided into high degree of polymerization, medium degree of polymerization and low degree of polymerization. Recently a product with high degree of polymerization was developed. There are usually three kinds of alcoholysis, namely 78, 88 and 98. Completely polyethylene ChunChun solution of alcoholysis degree is 98 ~ 100, partial alcoholysis of alcoholysis degree is generally 87 ~ 89, in order to convenient said, often take the degree of polymerization of thousands, hundreds of digits in front, put the percentage of alcoholysis degree behind, and PVA - 1788 indicates that the polymerization degree and alcoholysis degree for 1700 to 88, PVA - 1799, said polymerization degree and alcoholysis degree for 1700 to 99.
Pva-1788 is water-soluble and dissolves quickly in cold or hot water. PVA-1799 is only soluble in hot water above 95℃. As polyvinyl alcohol is basically neutral, no special corrosion requirements are required when dissolved, but it is best to use stainless steel reactor or enamel reactor, because in these materials, the solution will not be contaminated because of rust.