The Manufacture, Properties, and Uses of Polyvinyl Formal

Abstract

Polyvinyl formal ("Formvar" | is manufactured by simultaneous hydrolysis and aeeta~ization of polyvinyl acetate. Composition and resulting properties can be varied. These resins uniquely combine rigidity and toughness. Moldability is improved by lowered molecular weight and plasticizers. Solvents are few. Retention of more acetate groups leads to more general solubility and lowered strength and dimensional stability. A major application is in wire enamel, where cross-linking occurs. Solutions are also used for solenoid bonding and metal priming. Other applications include injection molding, calendering, reinforcement of more brittle resins, thermal adhesives for metals and plasticized compositions.