Poly propylene glycol is a kind of polymer, molecular formula H(C3H6O)nOH, molecular weight 400~2000, colorless to light yellow viscous liquid. Not volatile. Non-corrosive.
Transparent, colorless or basically colorless viscous liquid. According to the average molecular weight of 425, 1025 and 2025, it is divided into three types. Not volatile. It is soluble in water (low molecular weight) and aliphatic ketones and alcohols and other organic solvents, but insoluble in ether and most aliphatic hydrocarbons.
Refractive index n20/D 1.451
Flash point 230 °C
Solubility H2O: <0.01% (w/w) at 25 °C
PRACTICALLY INSOLUBLE (insoluble in water)
Lower molecular weight polymers are soluble in water, higher molecular weight polymers are only slightly soluble in water, soluble in oils, many hydrocarbons, and aliphatic alcohols, ketones, esters, etc.
Stable. Stable Substances to be avoided include strong oxidizing agents.
NIST Chemistry ReferencePolypropylene glycol 425(25322-69-4)_NIST
EPA Substance Registry SystemPoly[oxy(methyl- 1,2-ethanediyl)], .alpha.-hydro-.omega.-hydroxy- (25322-69-4)_EPA Substance
Melting point -40 °C
Density 1.01 g/mL at 20 °C
vapor density >1 (vs air) vapor density >1 (atmospheric pressure)
vapor pressure <0.01 mm Hg (20 °C) Vapor pressure: less than 0.01 mm Hg at 20 °C
use
Purpose 1 Used as defoamer
Use 2 Defoamer; solvent for vegetable oil, wax and resin. Used in eucalyptus, beverages, candy, yeast, etc.
Use 3 Defoamer. Used in the production of yeast and monosodium glutamate. The defoaming efficiency is several to tens of times that of edible oil.
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