Structure and Properties
Propylene glycol is a clear, colorless and hygroscopic liquid. Propylene glycol contains an asymmetrical carbon atom, so it exists in two stereoisomers. The commercial product is a racemic mixture. Pure optical isomers can be obtained by hydration of optically pure propylene oxide.
Propylene glycol is a component in newer automotive antifreezes and de-icers used at airports. Like ethylene glycol, the freezing point of water is depressed when mixed with propylene glycol due to increased opportunity for hydrogen bonding.
Read more about this topic: Propylene Glycol
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