Phthalic anhydride, abbreviated as PA, is a cyclic anhydride formed by dehydration of phthalic acid molecules. Soluble in hot water, soluble in phthalic acid in hot water; soluble in alcohol; insoluble in carbon disulfide; slightly soluble in cold water, a white needle crystal at room temperature (industrial phthalic anhydride is white flake crystal), It is flammable, easily sublimates below the boiling point, and has a special slight pungent odor. Phthalic anhydride can cause allergic symptoms of people’s respiratory organs. The dust or vapor of phthalic anhydride has a stimulating effect on the skin, eyes and respiratory tract, especially on moist tissues.
Phthalic anhydride is mainly used in the production of PVC plasticizers, unsaturated polyesters, alkyd resins and dyes, coatings, pesticides, pharmaceutical and instrument additives, edible saccharin, etc. It is an important organic chemical raw material. In the production of PVC, the maximum amount of plasticizer has exceeded 50%. With the rapid development of the plastic industry, the demand for phthalic anhydride has increased, which has promoted the rapid development of phthalic anhydride production at home and abroad.
The earliest production of phthalic anhydride began in 1872. At that time, the German BASF company used naphthalene as the raw material to oxidize chromic acid to produce phthalic anhydride, and then used fuming sulfuric acid to produce phthalic anhydride, but the yield was extremely low, only 15%. Since 1917, the world started to use vanadium oxide as a catalyst to produce phthalic anhydride with naphthalene. The production of phthalic anhydride has gradually been industrialized and scaled up, and two mature technologies, naphthalene method and ox base-method, have been formed successively.
Application
Phthalic anhydride is currently widely used in chemical, pharmaceutical, electronics, agricultural, coating, fine chemical and other industrial sectors. China’s phthalic anhydride is mainly used to produce phthalic acid plasticizers， which consumes about 60% of the total consumption while dyes and paints account for 25%, unsaturated resins and other products account for about 15%. Phthalic anhydride is an important organic chemical raw material, mainly used in the production of plastic plasticizers, alkyd resins, dyes, unsaturated resins and certain medicines and pesticides.
If you are interested, please feel free to contat us!
Guangzhou Chemicals Import & Export Co., Ltd
Address: 15th Floor, #691, RenMin Road North, Guangzhou city, China.
Zip code: 510170
Tel: +86 20 8108 1156 Fax: +86 20 8108 4009
Email: exp1@gzchem.com