GB1243583A - Polymerization of maleic, itaconic and aconitic anhydrides - Google Patents

Abstract

1,243,583. Polymerizing unsaturated acid anhydrides. FMC. CORP. 9 Sept., 1969 [10 Sept., 1968 (3)], No. 44507/69. Heading C3P. Maleic, itaconic and aconitic anhydrides are homopolymerized by heating to at least their melting points in the presence of mixed maleic-, itaconic- or aconitic-acyl peroxide respectively, which mixed peroxides have the formulµ (1) in the case of maleic anhydride (2) in the case of itaconic anhydride (3) in the case of aconitic anhydride wherein R, R 1 and R 2 are aliphatic or cycloaliphatic hydrocarbon groups of 1 to 6 carbon atoms or phenyl groups, which groups may be substituted with halogen or nitro, cyano, methoxy or ethoxy groups. Polymerization may be effected in bulk or in an inert liquid medium such as benzene, chlorobenzenes and alkyl acetates. The mixed acyl peroxides may be formed in situ by adding hydrogen peroxide and an acylating agent to the anhydride. The products may be converted to polyacids by reaction with water, and to metal salts, e.g. of alkali metals. Examples are given of the preparation of polymaleic anhydride from maleic anhydride, hydrogen peroxide and (1) acetic, (2) propionic, (3) benzoic, (4) cyclohexane carboxylic, (5) trichloroacetic, (6) trifluoroacetic and (8) mixed benzoic/acetic, formic/acetic, trichloroacetic/acetic, m - chlorobenzoic/acetic and cylcohexane carboxylic/acetic anhydrides, and (7) ketene; of polyitaconic anhydride from itaconic anhydride, hydrogen peroxide and (9) acetic, (10) propionic, benzoic, cyclohexane carboxylic, trichloroacetic and trifluoroacetic anhydrides, (12) mixed anhydrides as in (8), and (11) ketene; and of polyaconitic anhydride from aconitic anhydride, hydrogen peroxide and (13) acetic anhydride, (14) anhydrides as in (10), (16) mixed anhydrides as in (8), and (15) ketene; and the conversion of the products to the corresponding polyacids.