CAS 68460-01-5: 3H-2,1-Benzoxathiol-3-one, 4,5,6,7-tetrabromo-, 1,1-dioxide

Tetrabromo-2-sulfobenzoic acid cyclic anhydride (TBA) is a bifunctional monomer that is used in the production of polyesters. TBA is polymerized with terephthalic acid to produce poly(ethylene terephthalate), which is used in the manufacture of plastics and fibers. The TBA molecule has two reactive groups, one of which is a bromine atom that reacts with an alcohol group on another molecule to form a cyclic anhydride. This reaction leads to the formation of a carbon-oxygen-bromine ring, which can react with other molecules containing alcohol groups. The second reactive group on the TBA molecule is a sulfonic acid group that reacts with carboxylic acids or phenols to form esters. In the presence of ethylene glycol and trimellitic acid, TBA forms a film that can be used as a protective coating for paperboard packaging materials.