Production of polyvinyl butyral of reduced autohesion

Abstract

Abstract PURPOSE:To obtain the titled polyvinyl butyral suitable for use in laminated glass intermediate membranes, by heating and aging an aqueous dispersion containing a reaction product of polyvinyl alcohol with butyraldehyde and a phosphoric ester surfactant. CONSTITUTION:Polyvinyl alcohol is condensed with butyraldehyde in the presence of an acid catalyst such as sulfuric acid or p-toluenesulfonic acid. Before or after this condensation reaction, a phosphoric ester surfactant (e.g., alkyl phosphate or polyoxyethylene alkyl ether phosphate) is added to obtain an aqueous dispersion of the condensate containing about 0.03-1wt% above surfactant. Then, this aqueous dispersion of the condensate is heated to a temperature >=30 deg.C in a strongly acidic range and then aged by maintaining it at a temperature >=30 deg.C to obtain the purpose polyvinyl butyral with reduced autohesion.

Inventors

• 👤 Shigeru Nomura
• 👤 茂 野村
• 👤 Kunio Yanagisawa
• 👤 柳沢　邦夫

Bibliographic Details