Colorless viscous liquid. Melting point -77ºC, boiling point 207.5ºC, relative density 1.0043 (20/4ºC), viscosity (25ºC) 103.9mPa·s, refractive index 1.4401, surface tension (25ºC) 37.8mN, m, flash point 121ºC. Soluble in water, acetone, methyl ethyl (methyl) ketone, ethanol, dibutyl phthalate, castor oil, almost insoluble in aliphatic hydrocarbons, benzene, toluene, carbon tetrachloride, ethanolamines, mineral oil, linseed oil. When hot, it can dissolve nylon, but also partially dissolve shellac and turpentine. Due to the high boiling point, it is easy to be oxidized by air when distillation under normal pressure, so it is advisable to distillation under reduced pressure. Odorless, slightly bittersweet. Strong hygroscopic, can absorb the equivalent of its own weight of 12.5 water (relative humidity is 50), and even 38.5 water (relative humidity is 80). 1.3-butanediol has the characteristics of reactivity, odorless, low toxicity, good water solubility and so on. It is mainly used in organic synthesis, and is the raw material of polyester ester, alkyd resin, plasticizer, polyurethane coating, wetting agent and softener, intermediate of medicine and dye, surfactant, plasticizer, humectant, coupling agent, solvent, etc. Food additives and fragrances. Soluble in water, acetone, methyl/ethyl (methyl) ketone, ethanol, dibutyl phthalate, castor oil, almost insoluble in aliphatic hydrocarbons, benzene, toluene, carbon tetrachloride, ethanolamines, mineral oil, linseed oil. When hot, it can dissolve nylon, but also partially dissolve shellac and turpentine. Due to the high boiling point, it is easy to be oxidized by air when distillation under normal pressure, so it is advisable to distillation under reduced pressure. Odorless, slightly bittersweet.