Propylene glycol

Not to be confused with Polypropylene glycol, Ethylene glycol, or Polyethylene glycol.
This article is about 1,2-propanediol. For other propylene glycols, see Propanediol.
Propylene glycol[1]
Propylene glycol
ball-and-stick model
ball-and-stick model
Space-filling model
Space-filling model
Names
Preferred IUPAC name
Propane-1,2-diol
Other names
  • Propylene glycol
  • α-Propylene glycol
  • 1,2-Propanediol
  • 1,2-Dihydroxypropane
  • Methyl ethyl glycol
  • Methylethylene glycol
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
ECHA InfoCard 100.000.307 Edit this at Wikidata
EC Number
  • 200-338-0
E number E1520 (additional chemicals)
KEGG
RTECS number
  • TY6300000
UNII
  • InChI=1S/C3H8O2/c1-3(5)2-4/h3-5H,2H2,1H3 checkY
    Key: DNIAPMSPPWPWGF-UHFFFAOYSA-N checkY
  • CC(O)CO
Properties
C3H8O2
Molar mass 76.095 g·mol−1
Appearance colourless liquid
Odor odorless
Density 1.036 g/cm3
Melting point −59 °C (−74 °F; 214 K)
Boiling point 188.2 °C (370.8 °F; 461.3 K)
Miscible
Solubility in ethanol Miscible
Solubility in diethyl ether Miscible
Solubility in acetone Miscible
Solubility in chloroform Miscible
log P -1.34[2]
Vapor pressure 10.66 Pa (20 °C)
Thermal conductivity 0.34 W/m·K (50% H2O @ 90 °C (194 °F))
Viscosity 0.042 Pa·s
Thermochemistry
189.9 J/(mol·K) [3]
Pharmacology
QA16QA01 (WHO)
Hazards
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 0: Exposure under fire conditions would offer no hazard beyond that of ordinary combustible material. E.g. sodium chlorideFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
0
1
0
Related compounds
Related glycols
 Ethylene glycol, 1,3-propanediol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Propylene glycol (IUPAC name: propane-1,2-diol) is a viscous, colorless liquid. It is almost odorless and has a faintly sweet taste. Its chemical formula is CH3CH(OH)CH2OH. As it contains two alcohol groups, it is classified as a diol. An aliphatic diol may also be called a glycol. It is miscible with a broad range of solvents, including water, acetone, and chloroform. In general, glycols[6] are non-irritating and have very low volatility.[7]

It is produced on a large scale primarily for the production of polymers. In the European Union, it has E-number E1520 for food applications. For cosmetics and pharmacology, the number is E490. Propylene glycol is also present in propylene glycol alginate, which is known as E405. Propylene glycol is a compound which is GRAS (generally recognized as safe) by the US Food and Drug Administration under 21 CFR x184.1666, and is also approved by the FDA for certain uses as an indirect food additive. Propylene glycol is approved and used as a vehicle for topical, oral, and some intravenous pharmaceutical preparations in the U.S. and in Europe.

  1. ^ The Merck Index: An Encyclopedia of Chemicals, Drugs, and Biologicals. Merck & Co. 1989. ISBN 978-0911910285.
  2. ^ "Propylene Glycol_msds".
  3. ^ Zaripov, Z.I. (1982). Experimental study of the isobaric heat capacity of liquid organic compounds with molecular weights of up to 4000 a.e.m.
  4. ^ GHS: "Kein gefährlicher Stoff nach GHS" GESTIS 013620
  5. ^ "Propylene Glycol - Cameo Chemicals". NOAA Office of Response and Restoration. NOAA. Retrieved 3 October 2018.
  6. ^ Zapka, Maskrey (2016). Hawaii Energy and Environmental Technologies (HEET) Initiative.
  7. ^ Sullivan, Carl J.; Kuenz, Anja; Vorlop, Klaus-Dieter (2018). "Propanediols". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a22_163.pub2. ISBN 978-3527306732.