HYDROSOLUBLE, SLIGHTLY CURED POLYMALEIC ACID, PROCESS FOR ITS PREPARATION AND ITS USE

摘要

Slightly crosslinked, water-soluble polymaleic acid which is obtainable by polymerization of maleic anyhdride with from 0.1 to 10% by weight of a crosslinking agent in an aromatic hydrocarbon at from 60 to 200 DEG 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 DEG C. in 5% strength aqueous solution at pH 7 as the Na salt), a process for the preparation of slightly cross-linked polymaleic acid, and its use as a water treatment agent for reducing boiler scale and hard water deposits in water-conveying systems.