Purified Terephthalic acid (PTA)

It is white acicular crystal or powder. Flammable, low toxicity, density 1.510 g/cm3 . It sublimes at about 402℃ in usual atmospheric pressure, and melts at about 425 ℃in a sealed tube. It is soluble in alkali solution, slightly soluble in hot ethanol, and insoluble in water, ether, glacial acetic acid and chloroform. It is an important raw material for polyester resin, film, fiber, insulating paint and engineering plastics, etc.