Polyvinyl butyral (PVB) is a synthetic resin formed by condensation reaction of n-butyraldehyde and polyvinyl alcohol high-purity aqueous solution with reagent hydrochloric acid as catalyst. It is a white powder solid, insoluble in water, but soluble in ethanol, isopropanol, n-butanol, methoxypropanol, ethoxypropyl alcohol, dipropanol; Slightly soluble in esters and ketones; It is insoluble in aliphatic and aromatic hydrocarbons.