1, 2-propylene glycol, Linear molecular formula:CH3CH(OH)CH2OH CAS Number:57-55-6 Molecular weight:76.09 Beilstein:1340498 EC Number:200-338-0 TDS : Quality level 200 Vapor density 2.62 (vs air) Vapor pressure 0.08 mmHg (20 �°C) Spontaneous combustion temperature 779 �°F expl. lim.12.5 % Refractive index n20/D 1.432 (lit.) bp187 C (lit.) mp 60 C (lit.) density1.036 g/mL at 25 C (lit.) application(s) pharmaceutical (small molecule)