Polyvinyl alcohol (abbreviated as PVA) also can be called PVOH. PVA is unique among polymers (chemical compounds made up of large, multiple-unit molecules) in that it is not built up in polymerization reactions from single-unit precursor molecules known as monomers. Instead, PVA is made by dissolving another polymer, polyvinyl acetate, in an alcohol such as methanol and treating it with an alkaline catalyst such as sodium hydroxide. There are several brands of PVA in the world, and China PVA is one of best one. Our PVA1799,PVA2099,PVA2499 can replace PVA BF17 & PVA BF20 & PVABF24.