LOW LEVEL CHROMATE BASED CORROSION INHIBITION IN AQUEOUS MEDIUMS

摘要

A method and composition are disclosed for reducing the amount of corrosion of metal surfaces in contact with an aqueous medium comprising adding to the aqueous medium an effective amount for the purpose of a zinc-free treatment comprising: (i) water-soluble chromate, and (ii) water-soluble polymer comprising moieties derived from acrylic acid or water-soluble salt thereof and moieties of hydroxylated lower alkyl acrylate, wherein the moieties of said polymer have the following formulas: and X Y. where R is hydrogen or a lower alkyl of from 1 to 3 carbon atoms; R1 is OH, NH2 or OM where M is a water-soluble cation; R2 is a lower alkyl of from about 2 to 6 carbon atoms, R3 is H or lower alkyl of from 1 to 3 carbon atoms and the mole ratio of x:y is 1:4 to 36:1.