Поли(виниловый спирт)

Использование

NaA zeolite particles have been dispersed in a poly(vinyl alcohol) matrix to prepare a mixed-matrix membrane to study the pervaporative separation of water-butanol mixtures. Poly (vinyl alcohol)/gelatin based biocompatible polymeric scaffolds have been used to design for 3D cancer models.

Методы производства

Polyvinyl alcohol is produced through the hydrolysis of polyvinyl acetate. The repeating unit of vinyl alcohol is not used as the starting material because it cannot be obtained in the quantities and purity required for polymerization purposes. The hydrolysis proceeds rapidly in methanol, ethanol, or a mixture of alcohol and methyl acetate, using alkalis or mineral acids as catalysts.

Определение

ChEBI: Polyvinyl alcohol is a homopolymer macromolecule obtained by polymerisation of vinyl alcohol. It is used as a pharmaceutic aid and ophthalmic lubricant as well as in the manufacture of surface coatings artificial sponges, cosmetics, and other products.

Общее описание

Polyvinyl alcohol (PVOH) is a hydrophilic linear polymer which forms copolymers of vinyl alcohol and vinyl acetate. Hence, the structural properties of polyvinyl alcohol polymers depend on the extent of polymerization and hydrolysis. Such changes cause both chemical and physical modifications such as esterification, etherification, crystallization, ion-polymer complexation in the polymer. Modified- PVOH structures are useful in biomedical applications.

Фармацевтические приложения

Polyvinyl alcohol is used primarily in topical pharmaceutical and ophthalmic formulations. It is used as a stabilizing agent for emulsions (0.25–3.0% w/v). Polyvinyl alcohol is also used as a viscosity-increasing agent for viscous formulations such as ophthalmic products. It is used in artificial tears and contact lens solutions for lubrication purposes, in sustained-release formulations for oral administration, and in transdermal patches. Polyvinyl alcohol may be made into microspheres when mixed with a glutaraldehyde solution.

Промышленное использование

Polyvinyl alcohol is a tough, whitish polymerthat can be formed into strong films, tubes, andfibers that are highly resistant to hydrocarbonsolvents. Although polyvinyl alcohol is one ofthe few water-soluble polymers, it can be renderedinsoluble in water by drawing or by theuse of cross-linking agents.

Профиль безопасности

Questionable carcinogen with experimental carcinogenic and tumorigenic data by implant route. Flammable when exposed to heat or flame; can react with oxidizing materials. Slight explosion hazard in the form of dust when exposed to flame. To fight fire, use alcohol foam, CO2, dry chemical. When heated to decomposition it emits acrid smoke and irritating fumes.

Безопасность

Polyvinyl alcohol is generally considered a nontoxic material. It is nonirritant to the skin and eyes at concentrations up to 10%; concentrations up to 7% are used in cosmetics.
Studies in rats have shown that polyvinyl alcohol 5% w/v aqueous solution injected subcutaneously can cause anemia and infiltrate various organs and tissues.
(mouse, oral): 14.7 g/kg
(rat, oral): >20 g/kg

хранилище

Polyvinyl alcohol is stable when stored in a tightly sealed container in a cool, dry place. Aqueous solutions are stable in corrosionresistant sealed containers. Preservatives may be added to the solution if extended storage is required. Polyvinyl alcohol undergoes slow degradation at 100°C and rapid degradation at 200°C; it is stable on exposure to light.

Несовместимости

Polyvinyl alcohol undergoes reactions typical of a compound with secondary hydroxy groups, such as esterification. It decomposes in strong acids, and softens or dissolves in weak acids and alkalis. It is incompatible at high concentration with inorganic salts, especially sulfates and phosphates; precipitation of polyvinyl alcohol 5% w/v can be caused by phosphates. Gelling of polyvinyl alcohol solution may occur if borax is present.

Регуляторный статус

Included in the FDA Inactive Ingredients Database (ophthalmic preparations and oral tablets). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.