Methyl cellulose Chemische Eigenschaften,Einsatz,Produktion Methoden
S-Sätze Betriebsanweisung:
S24/25:Berührung mit den Augen und der Haut vermeiden.
Chemische Eigenschaften
Methyl cellulose is a water soluble, gel-like substance with no odor and no taste.
Verwenden
Methyl cellulose is used as a thickener and an emulsifier in various food and cosmetic products; as a gel in advanced cookery and as a lubricant. It is also involved in the treatment of constipation. It acts as a buffer additive in capillary electrophoresis to control electoosmotic flow for improved separations. In paper and textile industries, it is used as a sizing, thereby protecting the fibers from water or oil.
synthetische
Prepared from wood pulp or cotton by treatment with alkali and methylation of alkali cellulose with methyl chloride.
Vorbereitung Methode
Methylcellulose is prepared from wood pulp (cellulose) by
treatment with alkali followed by methylation of the alkali cellulose
with methyl chloride. The product is then purified and ground to
powder form.
Allgemeine Beschreibung
Odorless white or creamy white fibrous powder. Tasteless.
Air & Water Reaktionen
Methyl cellulose is hygroscopic. Swells in water to a viscous, colloidal solid. Slightly water soluble.
Reaktivität anzeigen
Methyl cellulose is incompatible with strong oxidizing agents. Methyl cellulose is also incompatible with aminacrine HCl, chlorocresol, mercuric chloride, phenol resorcinol, tannic acid and silver nitrate.
Brandgefahr
Flash point data for Methyl cellulose are not available; however, Methyl cellulose is probably combustible.
Sicherheitsprofil
A poison by
intraperitoneal route. When heated to
decomposition it emits acrid smoke and
irritating fumes.
Lager
Methylcellulose powder is stable, although slightly hygroscopic.
The bulk material should be stored in an airtight container in a cool,
dry place.
Solutions of methylcellulose are stable to alkalis and dilute acids
at pH 3–11, at room temperature. At pH less than 3, acid-catalyzed
hydrolysis of the glucose–glucose linkages occurs and the viscosity
of methylcellulose solutions is reduced.On heating, solution
viscosity is reduced until gel formation occurs at approximately
50°C;
Methylcellulose solutions are liable to microbial spoilage and
antimicrobial preservatives should therefore be used. Solutions may
also be sterilized by autoclaving, although this process can decrease
the viscosity of a solution.The change in viscosity after
autoclaving is related to solution pH. Solutions at pH less than 4 had viscosities reduced by more than 20% subsequent to autoclaving.
Inkompatibilitäten
chlorocresol; mercuric chloride; phenol; resorcinol; tannic acid;
silver nitrate; cetylpyridinium chloride; p-hydroxybenzoic acid; paminobenzoic
acid; methylparaben; propylparaben; and butylparaben.
Salts of mineral acids (particularly polybasic acids), phenols, and
tannins will coagulate solutions of methylcellulose, although this
can be prevented by the addition of ethanol (95%) or glycol
diacetate. Complexation of methylcellulose occurs with highly
surface-active compounds such as tetracaine and dibutoline sulfate.
High concentrations of electrolytes increase the viscosity of
methylcellulose mucilages owing to the ‘salting out’ of methylcellulose.
With very high concentrations of electrolytes, the methylcellulose
may be completely precipitated in the form of a discrete or
continuous gel. Methylcellulose is incompatible with strong
oxidizing agents.
Regulatory Status
GRAS listed. Accepted as a food additive in the USA, Europe and
Japan. Included in the FDA Inactive Ingredients Database
(sublingual tablets; IM injections; intrasynovial injections; nasal
preparations; ophthalmic preparations; oral capsules, oral suspensions,
and oral tablets; topical and vaginal preparations). Included
in nonparenteral medicines licensed in the UK. Included in the
Canadian List of Acceptable Non-medicinal Ingredients.Reported
in the EPA TSCA inventory.
Methyl cellulose Upstream-Materialien And Downstream Produkte
Upstream-Materialien
Downstream Produkte
