Carboxylic acid dianhydrides based on trimellitic anhydride
AssigneeCiba-Geigy Corporation
InventorsJurgen Habermeier, Eduard Knecht, Rudolf Gisler
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Abstract
Novel carboxylic acid dianhydrides are obtained by esterifying or trans-esterifying hydantoindiols, or diesters thereof, of the formula ##STR1## in which m and n are each a number from 1 to 4 and R.sub.1 and R.sub.2 are each an alkyl having 1 to 5 C atoms, or R.sub.1 and R.sub.2 together are the pentamethylene radical, R.sub.3 is a hydrogen atom or methyl and R.sub.4 is a hydrogen atom, acetyl or propionyl, with trimellitic anhydride. The novel dianhydrides are valuable curing agents for epoxide resins and are suitable for the preparation of polymers which are derived from carboxylic acid dianhydrides.
Claims5
A dianhydride of the formula I ##STR7## in which formula x is nought or a number from 1 to 10, m and n are each a number from 1 to 4 and R.sub.1 and R.sub.2 are each an alkyl having 1 to 5 C atoms, or R.sub.1 and R.sub.2 together are the pentamethylene radical, and R.sub.3 is a hydrogen atom or methyl.
Dependencies are inferred from the claim text.