SLIGHTLY CROSSLINKED, WATER-SOLUBLE POLYMALEIC ACID, ITS PREPARATION ANDITS USE

摘要

Slightly crosslinked, watersoluble polymaleic acid which is obtainable by polymerization of maleic anhydride with from 0.1 to 10% by weight of a crosslinking agent in an aromatic hydrocarbon at from 60 to 200.degree.C in the presence of from 1 to 20% by weight, based on maleic anhydride, of a peroxyester, and hydrolysis of the polymer to give slightly crosslinked polymaleic acid having a Fikentscher K value of from 8 to 20 (measured at 20.degree.C in 5% strength aqueous solution at pH 7 as the Na salt), a process for the preparation of slightly crosslinked polymaleic acid, and its use as a water treatment agent for reducing boiler scale and hard water deposits in water-conveying systems.