| CAS No.: | 26266-57-9 |
| Molecular Weight: | 402.57 g/mol |
| Chemical Formula | C22H42O6 |
Sorbitan monopalmitate or Sorbitan Palmitate is a nonionic emulsifier, surfactant and food additive. It has an E-number of E495. It is used in skin care, hair care and decorative cosmetics.
General Properties and Specifications of Sorbitan Monopalmitate:
Appearance: Cream to yellow solid waxy flakes or powder
Acid Value, mg KOH/gm: 7.5 maximum.
Saponification Value, mg KOH/gm: 140 – 150
Hydroxyl Value, mg KOH/gm: 275 – 305
Melting point: 44C to 51C literature.
Water: 1% maximum.
Solubility: Insoluble in cold water but dispersible in warm water. Soluble in ethanol. It is slightly soluble in isopropanol, xylene and liquid paraffin.
Appearance of 5% solution in ethanol: Clear colorless to slight yellowish.
Specifications of Sorbitan Monopalmitate USP NF Grade:
Sorbitan, esters, monohexadecanoate;
Sorbitan monopalmitate --- [CAS 26266-57-9].
DEFINITION
Sorbitan Monopalmitate is a partial ester of palmitic acid with Sorbitol and its mono- and dianhydrides. It yields, upon saponification, NLT 63.0% and NMT 71.0% of fatty acids, and NLT 32.0% and NMT 38.0% of polyols (w/w).
IDENTIFICATION
A.
Sample: Residue obtained in the Assay for Fatty Acids
Acceptance criteria
Fats and Fixed Oils, Acid Value: 210–225 on 1-g sample
Fats and Fixed Oils, Iodine Value: NMT 4
B. Thin-Layer Chromatographic Identification Test
To pass the test.
ASSAY
Fatty Acids:
To pass the test.
Acceptance criteria: 63.0%–71.0%
Polyols:
To pass the test.
Acceptance criteria: 32.0%–38.0% (w/w)
Residue on Ignition: NMT 0.5%
Water Determination, Method I: NMT 1.5%
Fats and Fixed Oils, Acid Value: NMT 8
Fats and Fixed Oils, Hydroxyl Value: 275–305
Fats and Fixed Oils, Saponification Value: 140–150
Packaging and Storage: Preserve in well-closed containers.
Specifications of Sorbitan Palmitate BP Ph Eur Grade:
Action and use: Non-ionic surfactant.
When sorbitan monopalmitate is demanded, Sorbitan Palmitate shall be supplied.
DEFINITION
Mixture usually obtained by partial esterification of sorbitol and its mono- and di-anhydrides with palmitic (hexadecanoic) acid.
CHARACTERS
Appearance: Yellow or yellowish powder, waxy flakes or hard masses.
Solubility: Practically insoluble in water, soluble in fatty oils, slightly soluble in ethanol (96 per cent).
IDENTIFICATION
A. Melting point: 44C to 51C.
Introduce the melted substance into the glass capillary tubes and allow to stand at a temperature below 10 °C for 24 h.
B. Hydroxyl value (see Tests).
C. Composition of fatty acids (see Tests).
TESTS
Acid value: Maximum 8.0, determined on 5.0 g.
Hydroxyl value: 270 to 305.
Peroxide value: Maximum 5.0.
Saponification value: 140 to 155.
Carry out the saponification for 1 h.
Composition of fatty acids: To pass the test by Gas chromatography.
Composition of the fatty acid fraction of the substance:
— palmitic acid: minimum 92.0 per cent;
— stearic acid: maximum 6.0 per cent.
Water: Maximum 1.5 per cent, determined on 1.00 g.
Total ash: Maximum 0.5 per cent.
