E 461 METHYL CELLULOSE

Commission Directive 98/86/EC

Synonyms Cellulose methyl ether

Definition Methyl cellulose is cellulose obtained directly from natural strains of

fibrous plant material and partially etherified with methyl groups

Chemical name Methyl ether of cellulose

Chemical formula The polymers contain substituted anhydroglucose units with the

following general formula: C₆H₇O₂(OR₁)(OR₂)(OR₃) where R₁, R₂, R₃ each may be one of the following:

- H

- CH₃ or

- CH₂CH₃

Molecular weight From about 20 000 to 380 000

Assay Content not less than 25 % and not more than 33 % of methoxyl groups

(-OCH₃) and not more than 5 % of hydroxyethoxyl groups (-OCH₂CH₂OH)

Description Slightly hygroscopic white or slightly yellowish or greyish odourless and

tasteless, granular or fibrous powder

Identification

A. Solubility Swelling in water, producing a clear to opalescent, viscous, colloidal solution.

Insoluble in ethanol, ether and chloroform.

Soluble in glacial acetic acid

Purity

Loss on drying Not more than 10 % (105 °C, 3 hours)

Sulphated ash Not more than 1,5 % determined at 800 ± 25 °C

pH of a 1 % colloidal solution Not less than 5,0 and not more than 8,0

Arsenic Not more than 3 mg/kg

Lead Not more than 5 mg/kg

Mercury Not more than 1 mg/kg

Cadmium Not more than 1 mg/kg

Heavy metals (as Pb) Not more than 20 mg/kg