ESTER GROUP-CONTAINING BLOCK POLYMERS SUITABLE AS ANTI-FOAMING AGENTS FOR AQUEOUS SYSTEMS

摘要

PCT No. PCT/EP94/02966 Sec. 371 Date Apr. 10, 1996 Sec. 102(e) Date Apr. 10, 1996 PCT Filed Sep. 6, 1994 PCT Pub. No. WO95/07742 PCT Pub. Date Mar. 23, 1995A method of using compositions as foam regulators for water-based systems with a tendency to foam is provided. The method employs a block copolymer containing ester groups corresponding to general formula (I): A-(CH2CH2O)n-B(I)in which n is an integer of 4 to 300, A is an optionally polymeric hydroxycarboxylic acid function and B is hydrogen, an alkyl or alkenyl radical containing 1 to 22 carbon atoms, a phenyl or benzyl radical or has the same meaning as A. Also provided is a granular free-flowing foam regulating formulation which contains 0.5% by weight to 30% by weight of the block copolymer containing ester groups adsorbed onto from 70% by weight to 99.5% by weight of a granular, substantially inorganic phosphate-free support material.