7568. Polyethylene Glycol

Nomenclature

CAS number: 25322-68-3
α-Hydro-ω-hydroxypoly(oxy-1,2-ethanediyl); macrogol; PEG; Carbowax (Union Carbide); Pluracol E (BASF); Poly-G (Olin); Polyglycol E (Dow).

Description and references

Liquid and solid polymers of the general formula H(OCH2CH2)nOH, where n is greater than or equal to 4. In general, each PEG is followed by a number which corresponds to its average mol wt. Synthesis: Fordyce, Hibbert, J. Am. Chem. Soc. 61, 1905, 1910 (1939). Polyethylene glycols are compds of low toxicity: Smyth et al., J. Am. Pharm. Assoc. Sci. Ed. 39, 349 (1950). Toxicity data (PEG 400): W. Bartsch et al., Arzneim.-Forsch. 26, 1581 (1976). Reviews: Glycols, G. O. Curme, F. Johnston, Eds. (Reinhold, New York, 1952) pp 176-202; Kastens in High Polymers, H. Mark et al., Eds., vol. 13 entitled Polyethers, part 1 (Interscience, New York, 1963) pp 169-189, 274-291; G. M. Powell, III in Handbook of Water-Soluble Gums & Resins, R. L. Davidson, Ed. (McGraw-Hill, New York, 1980) pp 18/1-18/31. Book: Poly(Ethylene Glycol) Chemistry: Biotechnical and Biomedical Applications, J. M. Harris, Ed. (Plenum Press, New York, 1992) 385 pp. Series of articles on pegylation to enhance delivery of protein drugs: Adv. Drug Delivery Rev. 54, 453-609 (2002). Clinical evaluation as laxative: S. Chaussade, M. Minic, Aliment. Pharmacol. Ther. 17, 165 (2003).

Properties

Clear, viscous liquids or white solids which dissolve in water forming transparent solns. Sol in many organic solvents. Readily sol in aromatic hydrocarbons. Only slightly sol in aliphatic hydrocarbons. Do not hydrolyze or deteriorate on storage, will not support mold growth. Solvent action on some plastics.

Derivative

Polyethylene glycol 200.

Properties

Average value of n is 4, mol wt range 190-210. Viscous, hygroscopic liq; slight characteristic odor; d2525 1.127. Viscosity (210°F): 4.3 cSt. Supercools upon freezing.

Derivative

Polyethylene glycol 400.

Properties

Average value of n between 8.2 and 9.1, mol wt range 380-420. Viscous, slightly hygroscopic liq; slight characteristic odor; d2525 1.128. mp 4-8°. Viscosity (210°F): 7.3 cSt. LD50 orally in rats: 30 ml/kg (Bartsch).

Derivative

Polyethylene glycol 600.

Properties

Average value of n between 12.5 and 13.9, mol wt range 570-630. Viscous, slightly hygroscopic liq; characteristic odor; d2525 1.128. mp 20-25°. Viscosity (210°F): 10.5 cSt.

Derivative

Polyethylene glycol 1500.

Properties

Average value of n between 29 and 36, mol wt range 1300-1600. White, free-flowing powder; d2525 1.210. mp 44-48°. Viscosity (210°F): 25-32 cSt.

Derivative

Polyethylene glycol 4000.

Nomenclature

Forlax (Ipsen); Idrolax (Schwarz).

Properties

Average value of n between 68 and 84, mol wt range 3000-3700. White, free-flowing powder or creamy-white flakes; d2525 1.212. mp 54-58°. Viscosity (210°F): 76-110 cSt. LD50 orally in rats (divided doses): 59 g/kg (Smyth).

Derivative

Polyethylene glycol 6000.

Properties

Average value of n between 158 and 204, mol wt range 7000-9000. Powder or creamy-white flakes; d2525 1.21. mp 56-63°. Viscosity (210°F): 470-900 cSt. LD50 orally in rats: >50 g/kg (Smyth).

Use

Pharmaceutic aid (ointment and suppository base; tablet excipient). As water-soluble lubricants for rubber molds, textile fibers, and metal-forming operations. In food and food packaging. In hair prepns, in cosmetics in general. As a stationary phase in gas chromatography. Also in water paints, paper coatings, polishes and in the ceramics industry.

Therapeutic Category

Laxative.

Keywords

Laxative/Cathartic