13propanediol

1,3-Propanediol, or propan-1,3-diol, is an aliphatic diol with the formula HO-CH2-CH2-CH2-OH. It is a colorless, hygroscopic liquid that is miscible with water and many organic solvents. The compound has two primary hydroxyl groups separated by a three-carbon chain, making it useful as a versatile building block in polymers and as a solvent or humectant.

Production methods include catalytic hydrogenolysis of glycerol, which links the diol to renewable feedstocks derived from biodiesel. Another route uses fermentation of glycerol by certain microorganisms to yield 1,3-propanediol, followed by purification. These routes allow both petrochemical and bio-based supply, with ongoing research aimed at improving selectivity and efficiency.

Applications center on its role as a monomer and intermediate. It is a key precursor in the production of polytrimethylene terephthalate (PTT), a polyester valued for its elasticity and dyeability. 1,3-Propanediol is also used as a solvent and humectant in cosmetics and personal care products, and as a chemical intermediate for esters, polyurethanes, and other polymers. In some formulations, it serves as a non-volatile plasticizer or as a component in heat-transfer and antifreeze formulations, though its use in these areas varies by region and regulatory status.

Physical properties include its miscibility with water and many solvents, a relatively high boiling point for a small diol, and a tendency to form hydrogen-bonded networks that influence viscosity and crystallization behavior in polymers. Safety considerations are similar to other diols: it presents low acute toxicity but can cause irritation with improper handling. Environmental considerations favor renewable, bio-based production routes where feasible. See also 1,2-propanediol.