Products
Polyvinyl alcohol is used as an excipient in many drugs, especially in film-coated tablets.
Structure and properties
Polyvinyl alcohol exists as a yellowish white and odorless powder or as translucent granules and is soluble in water. Different types are distinguished. The substance is obtained by polymerization of vinyl acetate followed by partial or almost complete hydrolysis of the polyvinyl acetate in the presence of catalytic amounts of alkalis and mineral acids. The average molecular mass ranges from 20,000 to 150,000.
Effects
Polyvinyl alcohol forms clear, well adherent and water soluble films and has viscosity increasing properties.
