Polypropylene glycol (PPG), with the formula H(C3H6O)nOH, is a colorless to pale yellow viscous liquid. It is non-volatile, non-corrosive, and has a molecular weight ranging from 400 to 2050. Lower molecular weight PPG is soluble in water, while higher molecular weight forms are slightly soluble in water but dissolve in oils, hydrocarbons, alcohols, ketones, and esters. The hydroxyl groups at both ends enable esterification to form monoesters or diesters. Monoesters act as non-ionic surfactants and can form ethers with alcohols. PPG is used as a solvent for oils, resins, and waxes, and in producing alkyd resins, emulsifiers, lubricants, and plasticizers. It is synthesized by condensing propylene oxide and propylene glycol under high pressure or acidic catalysts.
Parameters
Melting point | -40 °C |
Boiling point | >300 °C |
density | 1.01 g/mL at 20 °C |
vapor density | >1 (vs air) |
Pour Point | -26 |
Pour Point | -45 |
vapor pressure | <0.01 mm Hg ( 20 °C) |
refractive index | n |
Fp | 230 °C |
solubility | H2O: <0.01 % (w/w) at 25 °C |
form | Viscous Liquid |
Specific Gravity | 1.005 |
color | White to light gray |
Water Solubility | PRACTICALLY INSOLUBLE |
FreezingPoint | -25 |
FreezingPoint | -40 |
Stability: | Stable. Substances to be avoided include strong oxidizing agents. |
LogP | 0.01 at 25℃ |
NIST Chemistry Reference | Polypropylene glycol 425(25322-69-4) |
EPA Substance Registry System | Polypropylene glycol (25322-69-4) |
Safety Information
Safety Statements | 24/25 |
WGK Germany | 1 |
RTECS | TR5250000 |
TSCA | Yes |
HS Code | 39072090 |
Hazardous Substances Data | 25322-69-4(Hazardous Substances Data) |
Polymer science-related materials, including both hydrophobic polymers and polymer-based organic compounds, as well as inorganic compounds and salts. Applications span across professional reagents, food processing additives (such as defoaming agents), and pesticide auxiliaries. This category includes the Polypropylene Glycol (PPG) series—PPG-200, PPG-400, PPG-1000, PPG-2000, and PPG-4000—widely used in the organic chemical industry. These are essential chemical raw materials with broad use in pharmaceuticals, cosmetics, biochemical reagents, alcohol-based intermediates, and active pharmaceutical ingredients (APIs), especially for pharmaceutical, pesticide, and dye manufacturing.
