Annex II

United Kingdom

In the Annex to Regulation (EU) No 231/2012 the following entry for E 463a (Low-substituted hydroxypropyl cellulose (L-HPC)) is inserted after the entry for E 463 (Hydroxypropyl cellulose):

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E 463a LOW-SUBSTITUTED HYDROXYPROPYL CELLULOSE (L-HPC)
Synonyms Cellulose hydroxypropyl ether, low substituted
Definition
L-HPC is a low-substituted poly (hydroxypropyl) ether of cellulose.

L-HPC is manufactured by partial etherification of the anhydroglucose units of pure cellulose (wood pulp) with propylene oxide/hydroxypropyl groups. The resulting product is then purified, dried and milled to yield low-substituted hydroxypropyl cellulose.

L-HPC contains not less than 5,0 % and not more than 16,0 % of hydroxypropoxy groups, calculated on the dried basis.

L-HPC differs from hydroxypropyl cellulose (E 463) with respect to the degree of molar substitution with hydroxypropoxy groups of the glucose ring unit (0,2 for L-HPC vs 3,5 for E 463) of the cellulose backbone.

IUPAC name Cellulose, 2-hydroxypropyl ether (low substituted)
CAS number 9004-64-2
Einecs number
Chemical name Hydroxypropyl ether of cellulose, low-substituted
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

CH₂CHOHCH₃

CH₂CHO(CH₂CHOHCH₃)CH₃

CH₂CHO[CH₂CHO(CH₂CHOHCH₃)CH₃]CH₃

Molecular weight From about 30 000 to 150 000 g/mol
Assay
The average number of hydroxypropoxy groups

(–OCH₂CHOHCH₃) corresponds to 0,2 hydroxypropyl groups per anhydroglucose unit on the anhydrous basis

Particle size
by laser diffraction method — Not less than 45 μm (not more than 1 % in weight of particles of less than 45 μm) and not more than 65 μm

by size-exclusion chromatography (SEC) — Average (D50) particle size between 47,3 μm and 50,3 μm; D90 value (90 % below given value) between 126,2 μm and 138 μm

Description Slightly hygroscopic white or slightly yellowish or greyish odourless and tasteless, granular or fibrous powder
Identification Passes test
Solubility Insoluble in water; swelling in water. It dissolves in a solution of 10 % sodium hydroxide producing a viscous solution.
Assay Determination of the degree of molar substitution by gas chromatography
pH Not less than 5,0 and not more than 7,5 (1 % colloidal suspension)
Purity
Loss on drying Not more than 5,0 % (105 °C, 1 hour)
Residue on ignition Not more than 0,8 % determined at 800 °C ± 25 °C
Propylene chlorohydrins Not more than 0,1 mg/kg (on an anhydrous basis) (gas chromatography–mass spectrometry (GC–MS))
Arsenic Not more than 2 mg/kg
Lead Not more than 1 mg/kg
Mercury Not more than 0,5 mg/kg
Cadmium Not more than 0,15 mg/kg

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E 463a LOW-SUBSTITUTED HYDROXYPROPYL CELLULOSE (L-HPC)
Synonyms	Cellulose hydroxypropyl ether, low substituted
Definition	L-HPC is a low-substituted poly (hydroxypropyl) ether of cellulose. L-HPC is manufactured by partial etherification of the anhydroglucose units of pure cellulose (wood pulp) with propylene oxide/hydroxypropyl groups. The resulting product is then purified, dried and milled to yield low-substituted hydroxypropyl cellulose. L-HPC contains not less than 5,0 % and not more than 16,0 % of hydroxypropoxy groups, calculated on the dried basis. L-HPC differs from hydroxypropyl cellulose (E 463) with respect to the degree of molar substitution with hydroxypropoxy groups of the glucose ring unit (0,2 for L-HPC vs 3,5 for E 463) of the cellulose backbone.
IUPAC name	Cellulose, 2-hydroxypropyl ether (low substituted)
CAS number	9004-64-2
Einecs number
Chemical name	Hydroxypropyl ether of cellulose, low-substituted
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 CH₂CHOHCH₃ CH₂CHO(CH₂CHOHCH₃)CH₃ CH₂CHO[CH₂CHO(CH₂CHOHCH₃)CH₃]CH₃
Molecular weight	From about 30 000 to 150 000 g/mol
Assay	The average number of hydroxypropoxy groups (–OCH₂CHOHCH₃) corresponds to 0,2 hydroxypropyl groups per anhydroglucose unit on the anhydrous basis
Particle size	by laser diffraction method — Not less than 45 μm (not more than 1 % in weight of particles of less than 45 μm) and not more than 65 μm by size-exclusion chromatography (SEC) — Average (D50) particle size between 47,3 μm and 50,3 μm; D90 value (90 % below given value) between 126,2 μm and 138 μm
Description	Slightly hygroscopic white or slightly yellowish or greyish odourless and tasteless, granular or fibrous powder
Identification	Passes test
Solubility	Insoluble in water; swelling in water. It dissolves in a solution of 10 % sodium hydroxide producing a viscous solution.
Assay	Determination of the degree of molar substitution by gas chromatography
pH	Not less than 5,0 and not more than 7,5 (1 % colloidal suspension)
Purity
Loss on drying	Not more than 5,0 % (105 °C, 1 hour)
Residue on ignition	Not more than 0,8 % determined at 800 °C ± 25 °C
Propylene chlorohydrins	Not more than 0,1 mg/kg (on an anhydrous basis) (gas chromatography–mass spectrometry (GC–MS))
Arsenic	Not more than 2 mg/kg
Lead	Not more than 1 mg/kg
Mercury	Not more than 0,5 mg/kg
Cadmium	Not more than 0,15 mg/kg