Propylene Glycol (Propane-1,2-diol))

Propylene glycol (propane-1,2-diol) featuring a three-carbon chain with two hydroxyl (-OH) groups on adjacent carbons (1 and 2), making it a diol, or dihydric alcohol; it's a colorless, viscous liquid used widely as a solvent, humectant, and antifreeze due to its water solubility and low toxicity compared to ethylene glycol.