Cellulose hydroxyethylmethyl

Hydroxy propyl cellulose, like methyl cellulose, is soluble in cold water but not in hot, precipitating above 38°C. It was introduced by Hercules in 1968 (Klucel) for such uses as adhesive thickeners, binders, cosmetics and as protective colloids for suspension polymerisation. The Dow company market the related hydroxypropylmethyl cellulose (Methocel) and also produce in small quantities a hydroxyethylmethyl cellulose. 

Hydroxyethylmethyl cellulose 5 Although this material is practically insoluble in hot water (above 60°C), it can dissolve in cold water to form a colloidal solution and has similar properties to HPMC. 

Methyl cellulose Ethyl cellulose Hydroxyethyl cellulose Hydroxypropyl cellulose Hydroxyethylmethyl cellulose Hydroxypropylmethyl cellulose Carboxymethyl cellulose sodium Cellulose acetate Cellulose acetate butyrate Cellulose acetate propionate Cellulose acetate phthalate Hydroxypropylmethyl cellulose phthalate... 

Hydroxyethyl cellulose hydroxyethylmethyl cellulose methyl-cellulose. 

The PhEur 2005 describes hydroxyethylmethyl cellulose as a partly O-methylated and 0-(2-hydroxyethylated) cellulose. Various different grades are available, which are distinguished by appending a number indicative of the apparent viscosity in millipascal seconds (mPas) of a 2% w/v solution measured at 20°C. 

Hydroxyethylmethyl cellulose is hygroscopic and should therefore be stored under dry conditions away from heat. 

Hydroxyethylmethyl cellulose is used as an excipient in a wide range of pharmaceutical products, including oral tablets and suspensions and topical gel preparations. It has similar properties to methylcellulose, but the hydroxyethyl groups make it more readily soluble in water and solutions are more tolerant of salts and have a higher coagulation temperature. 

Hydroxyethylmethyl cellulose is used as an excipient in various oral and topical pharmaceutical preparations and is generally regarded as an essentially nontoxic and nonirritant material. See Hypromellose for further information. 

Ethylcellulose hydroxyethyl cellulose hydroxyethylmethyl cellulose hypromellose. 

Synonyms Cellulose, 2- hydroxyethyl methyl ether Hydroxyethylmethyl-cellulose MHEC... 

Ethyl cellulose Hydroxyethyl cellulose Hydroxypropyl cellulose Methyl cellulose Cellulose acetate Hydroxypropylmethyl cellulose Hydroxybutylmethyl cellulose Hydroxyethylmethyl cellulose Ethylhydroxyethyl cellulose Cellulose xanthate... 

Properties. Methylcellulose [9004-67-5] (MC) and its alkylene oxide derivatives hydroxypropylmethylcellulose [9004-65-3] (HPMC), hydroxyethylmethyl-cellulose [9032-42-2] (HEMC), and hydroxybutylmethylcellulose [9041-56-9] (HBMC) are nonionic, surface-active, water-soluble polymers. Each type of derivative is available in a range of methyl and hydroxyalkyl substitutions. The extent and imiformity of the methyl substitution and the specific type of hydroxyalkyl substituent affect the solubility, surface activity, thermal gelation, and other properties of the poljuners in solution. 

Hydroxyethylmethyl cellulose R = H, CH3 or [-CH CH20-]niH (Culminal Hercules) Viscosity = 100-70,000 MPa for 2% aqueous solution Suspending and a thickening agent... 

All these types are defined in pharmacopoeias (US National Formulary / Pharmacopoeia, European Pharmacopoeia) or food compendiums (Food Chemicals Codex). Other less common or no longer commercially available derivatives are hydroxyethylmethyl cellulose (HEMC), ethylhydroxyethyl cellulose (EHEC), hydroxbutylmethyl cellulose (HBMC) and sodium carboxymethylhydroxyethyl cellulose (NaCMHEC). 

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