Поливинилпирролидон

Химические свойства

Hygroscopic, white or yellowish-white powder or flakes.

Использование

Polyvinylpyrrolidone is used as an adhesive in glue sticks; an emulsifier and a disintegrant for solution polymerization; an additive to Doro's RNA extraction buffer; as a liquid-phase dispersion enhancing agent in diffusion-ordered spectroscopy (DOSY) NMR and as a thickening agent in tooth whitening gels. It finds use in personal care products like shampoos and toothpastes, in ink for inkjet printers as well as in contact lens solutions. It is used as a food additive and in the wine industry as a fining agent for white wine. It is used as a capping agent to synthesize silver nanowires through a polyol process.

Методы производства

Povidone is manufactured by the Reppe process. Acetylene and formaldehyde are reacted in the presence of a highly active copper acetylide catalyst to form butynediol, which is hydrogenated to butanediol and then cyclodehydrogenated to form butyrolactone. Pyrrolidone is produced by reacting butyrolactone with ammonia. This is followed by a vinylation reaction in which pyrrolidone and acetylene are reacted under pressure. The monomer, vinylpyrrolidone, is then polymerized in the presence of a combination of catalysts to produce povidone.

Определение

ChEBI: A vinyl polymer composed of repeating -CH2-CR- units where R is a 2-oxopyrrolidin-1-yl group.

Подготовка

N-Vinylpyrrolidone is prepared from 1,4-butanediol as follows:

N -Vinylpyrrolidone is water-soluble and is usually polymerized in aqueous solution at about 50??C with ammonia and hydrogen peroxide. The polymer is also water-soluble and is isolated by spray-drying. Commercial grades of polyvinylpyrrolidone (PVP) have average molecular weights (Mv) ranging from about 10000 up to 360000.
The largest use of polyvinylpyrrolidone is in cosmetic formulations, especially hair lacquers. In the latter applications, polyvinylpyrrolidone is the preferred film-former on account of good adhesion to hair, lustre of the film and ease of removal on washing. The polymer is also used as a binder in pharmaceutical tablets. Polyvinylpyrrolidone also finds use in the textile industry, particularly in colour stripping operations, where the great affinity of the polymer for dyestuffs is utilized. An interesting application of polyvinylpyrrolidone is in aqueous solution as a blood plasma substitute; such material was extensively used in Germany during the Second World War.

Всемирная организация здравоохранения(ВОЗ)

Polyvidone, a polymer of vinylpyrrolidinone, is an excipient used as a suspending and dispersing agent. Injectable preparations containing polymers with a molecular weight in the order of 12,000 have caused painful local granulomatous lesions. This has led to the withdrawal of polyvidone from such preparations in some countries. Polyvidone was formerly also used as a plasma expander but, because it was sequestered within the liver and spleen, this use has been discontinued. However, it remains widely used as a vehicle for ophthalmic preparations, and as the major component of artificial tears.

Общее описание

White powder. Compatible with a wide range of hydrophilic and hydrophobic resins.

Реакции воздуха и воды

Hygroscopic. Water soluble.

Профиль реактивности

Polyvinylpyrrolidone is a polymeric material and probably has low reactivity. Polyvinylpyrrolidone reacts as a weak base.

Опасность

Questionable carcinogen.

Угроза здоровью

SYMPTOMS: Polyvinylpyrrolidone may cause interstitial fibrosis in the lungs. Lesions regress when patient is no longer being exposed to the compound.

Пожароопасность

Flash point data for Polyvinylpyrrolidone are not available, but Polyvinylpyrrolidone is probably non-flammable.

Фармацевтические приложения

Although povidone is used in a variety of pharmaceutical formulations, it is primarily used in solid-dosage forms. In tableting, povidone solutions are used as binders in wet-granulation processes.Povidone is also added to powder blends in the dry form and granulated in situ by the addition of water, alcohol, or hydroalcoholic solutions. Povidone is used as a solubilizer in oral and parenteral formulations, and has been shown to enhance dissolution of poorly soluble drugs from solid-dosage forms. Povidone solutions may also be used as coating agents or as binders when coating active pharmaceutical ingredients on a support such as sugar beads.
Povidone is additionally used as a suspending, stabilizing, or viscosity-increasing agent in a number of topical and oral suspensions and solutions. The solubility of a number of poorly soluble active drugs may be increased by mixing with povidone.
Special grades of pyrogen-free povidone are available and have been used in parenteral formulations;

Контактные аллергены

Polyvinylpyrrolidone is widely used as is in cosmetics such as hair care products and in medical products. It acts as iodophor in iodine-polyvinylpyrrolidone. PVP is an irritant and has been claimed as the allergen in some cases of dermatitis from iodine-polyvinylpyrrolidone (although iodine is more likely the hapten). It may cause type I contact urticaria or anaphylaxis.

Профиль безопасности

Mtldly toxic by intraperitoneal and intravenous routes. Questionable carcinogen. When heated to decomposition it emits toxic fumes of NOx.

Безопасность

Povidone has been used in pharmaceutical formulations for many years, being first used in the 1940s as a plasma expander, although it has now been superseded for this purpose by dextran.
Povidone is widely used as an excipient, particularly in oral tablets and solutions. When consumed orally, povidone may be regarded as essentially nontoxic since it is not absorbed from the gastrointestinal tract or mucous membranes.Povidone additionally has no irritant effect on the skin and causes no sensitization. exists that povidone may accumulate in the organs of the body following intramuscular injection.
A temporary acceptable daily intake for povidone has been set by the WHO at up to 25 mg/kg body-weight.
(mouse, IP): 12 g/kg

хранилище

Povidone darkens to some extent on heating at 150°C, with a reduction in aqueous solubility. It is stable to a short cycle of heat exposure around 110–130°C; steam sterilization of an aqueous solution does not alter its properties. Aqueous solutions are susceptible to mold growth and consequently require the addition of suitable preservatives.
Povidone may be stored under ordinary conditions without undergoing decomposition or degradation. However, since the powder is hygroscopic, it should be stored in an airtight container in a cool, dry place.

Методы очистки

Purify it by dialysis, and freeze-drying. Also by precipitation from CHCl3 solution by pouring into ether. Dry it in a vacuum over P2O5. For the crosslinked polymer purification is by boiling for 10minutes in 10% HCl and then washing with glass-distilled water until free from Cl ions. Finally, Cl ions are removed more readily by neutralising with KOH and continued washing.

Несовместимости

Povidone is compatible in solution with a wide range of inorganic salts, natural and synthetic resins, and other chemicals. It forms molecular adducts in solution with sulfathiazole, sodium salicylate, salicylic acid, phenobarbital, tannin, and other compounds; see Section 18. The efficacy of some preservatives, e.g. thimerosal, may be adversely affected by the formation of complexes with povidone.

Регуляторный статус

Accepted for use in Europe as a food additive. Included in the FDA Inactive Ingredients Database (IM and IV injections; ophthalmic preparations; oral capsules, drops, granules, suspensions, and tablets; sublingual tablets; topical and vaginal preparations). Included in nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.