7578. Polyoxyethylene Fatty Acid Esters

Nomenclature

Polyethylene glycol esters of fatty acids; PEG fatty acid esters; POE fatty acid esters; ethoxylated fatty acid esters; macrogol fatty acid esters.

Description and references

Nonionic surfactants prepared commercially by esterification of fatty acids with ethylene oxide or with polyethylene glycol. Of the general structure RCOO(CH2CH2O)nH or RCOO(CH2CH2O)nOCR where R is a long chain alkyl group or mixture of alkyl groups. Wide range of properties achieved by changing the hydrophobic fatty acid segment and/or varying the degree of polymerization of the hydrophilic polyoxyethylene segment. Trademarks for some commercially available series of compounds include Emerest (2600, 2700 series), Emulsynt, Ethofat, Lipopeg, Mapeg, Myrj, Nopalcol, Pegosperse, Renex 20, Varonic LI. Review of prepn, properties and uses: W. B. Satkowski et al., “Polyoxyethylene Esters of Fatty Acids” in Nonionic Surfactants, M. J. Schick, Ed. (Dekker, New York, 1967) pp 142-174.

Properties

Liquids, soft solids, solids or flakes. Solubility properties depend on length of polyoxyethylene (POE) segment added to a specific fatty acid. Sol in oil and hydrocarbon solvents when <8 ethylene oxide units are added. Soly in water begins when 12-15 ethylene oxide units are added. Specific gravity and viscosity increase with increasing ethylene oxide content.

Derivative

Polyoxyl 8 stearate.

Nomenclature

Polyethylene glycol 400 monostearate; PEG-400 monostearate; POE (8) stearate; macrogol ester 400; Emerest 2711 (Emery); Lipopeg 4-S (Lipo); Myrj 45 (ICI); Mapeg 400 MS (PPG); Pegosperse 400-MS (Lonza).

Description and references

C17H35COO(CH2CH2)nH where the average value of n is 8. Prepn and properties: R. L. Birkmeier, J. D. Brandner, J. Agric. Food Chem. 6, 471 (1958).

Derivative

Polyoxyl 40 stearate.

Nomenclature

Polyoxyethylene (40) stearate; POE (40) monostearate; Myrj 52 (ICI); Myrj 52S (ICI); Pegosperse 1750-MS (Lonza).

Properties

The average number of oxyethylene units is 40. Waxy, white to light tan solid; odorless or faint fat-like odor. Sol in water, alc, ether, acetone. Insol in mineral oil, vegetable oils.

Use

As antistats, emulsifiers, defoamers, wetting agents, solubilizers, conditioning agents, lubricants, detergents. Have wide range of cosmetic, pharmaceutical and other industrial applications. Polyoxyl 8 and 40 stearates as pharmaceutic aid (surfactant).