Isophthalic acid

Isophthalic acid or 1,3-benzenedicarboxylic acid is a colourless, crystalline powder that is insoluble in cold water and poorly soluble in boiling water. The melting point of isophthalic acid is 345-348°C and the auto-ignition temperature exceeds 650°C. The relative density of isophthalic acid is greater than that of water, at 1.54. This equates to a specific gravity of 1540 kg/m3.