CAS: 57-55-6 Melting point: -60 °C (lit.) Boiling point: 187 °C (lit.) Density: 1.036 g/mL at 25 °C (lit.) Vapor density: 2.62 (vs air) Vapor pressure: 0.08 mmHg (20 °C) Refractive index: n20/D 1.432 (lit.) FEMA: 2940 Flash point: 225 °F Storage condition: Store at +5 °C to +30 °C. Solubility: Slightly soluble in chloroform, slightly soluble in ethyl acetate, slightly soluble in methanol. pKa: 14.49±0.20 (Predicted) Form: Viscous liquid Color: APHA ≤10 Specific gravity: 1.038 (20/20℃), 1.036～1.040 Odor: Odorless, with very faint alcoholic smell pH: 6-8 (100g/L, H₂O, 20℃) Explosion limit: 2.4-17.4% (V) Source: synthetic Optical Rotation: -0.11° (C=1.00 g/100ml, CHCl₃) Water solubility: Miscible Thermal conductivity: 0.199 W/(m·K) at 25℃ Cp (liquid): 2.51 J/(g·K), at 25℃ Sensitivity: Hygroscopic Merck: 14,7855 JECFA Number: 925 BRN: 1340498 Henry's Law Constant: 2.7×10³ mol/(m³·Pa) at 25℃, Burkholder et al. (2019) Dielectric constant: 32.0 Surface tension: 35.44 mN/m at 298.15 K InChI: 1S/C3H8O2/c1-3(5)2-4/h3-5H,2H2,1H3 InChIKey: DNIAPMSPPWPWGF-UHFFFAOYSA-N SMILES: CC(O)CO LogP: -0.92 NIST chemical substance information: Propylene glycol (57-55-6) EPA chemical substance information: Propylene glycol (57-55-6)

Description: Propylene glycol (1,2-propanediol) is a hygroscopic viscous liquid. It is miscible with water, acetone, ethyl acetate and chloroform, soluble in ether. It can dissolve many essential oils, immiscible with petroleum ether, paraffin and grease. It is stable to heat and light, more stable at low temperature. It belongs to diol and can react with organic acids, inorganic acids, epoxypropane, hydrogen halide and acetaldehyde.

Application: Used as solvent, plasticizer, humectant and solubilizer for cosmetics, food and industrial formulations.

Stability & Storage: Chemically stable at room temperature. It will be oxidized when exposed at high temperature above 280℃ in open environment. Stable after mixing with 95% ethanol or water. Hygroscopic. Store in cool, dry, dark and airtight container.

Incompatibility: Incompatible with strong oxidizing agents such as potassium permanganate.