Поливинилпирролидон химические свойства, назначение, производство
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.
Поливинилпирролидон препаратная продукция и сырье
сырьё
препарат