What Is Polyvinyl Alcohol?
Polyvinyl alcohol is a type of water-soluble synthetic resin.
It was invented in Germany in 1924. It was invented in Germany in 1924 and has since been industrially developed by Japanese companies.
Polyvinyl Alcohol Manufacturing Process
Polyvinyl alcohol, the monomer of polyvinyl alcohol, cannot exist as a monomer because it is isomerized to the more stable acetaldehyde. Polyvinyl alcohol is therefore synthesized via polyvinyl acetate.
Industrially, vinyl acetate is synthesized from petroleum-derived ethylene, acetic acid, and oxygen. Palladium catalysts are used in this reaction.
Polyvinyl acetate is obtained by addition polymerization of the vinyl acetate. Polyvinyl alcohol is then synthesized by hydrolyzing polyvinyl acetate.
Properties of Polyvinyl Alcohol
Polyvinyl alcohol exists as a solid at room temperature and is soluble in warm water. This feature of solubility in warm water is unique among synthetic resins. This feature is due to the large amount of hydrophilic hydroxy groups (-OH groups) in the molecule.
This polyvinyl alcohol has properties, such as adhesion to hydrophilic surfaces, film formation, and viscosity.
It is also a stable polymer that does not easily change or deteriorate in various environments, making it an easy substance to handle over the long term. It has chemical resistance and dissolves only in special solvents such as dimethyl sulfoxide and water. It has almost no skin irritation, eye irritation, or skin sensitization, making it a safe substance for the human body.
Uses of Polyvinyl Alcohol
Polyvinyl alcohol is used in a wide variety of applications due to its properties.
Taking advantage of its water solubility and adhesive properties, it is used in cosmetics and as an adhesive or sizing agent.
When used in cosmetics, it is used for film formation and emulsion stabilization. By forming a film, liquid products such as foundation and mascara become a soft film and stay on the skin more easily.
When formulated as an adhesive, it is also used as a substance that serves as an adhesive as it is, and is often sold in the form of liquid glue. It is also used as a glue for the backs of stamps. It is also used as a synthetic laundry glue as a glue agent.
It is also used as a base material for polarizing plates used in liquid crystal displays. It is also used as a raw material for the synthetic fiber vinylon.