Reaction prod. from ethylene! oxide copolymer and poly:amine - useful as corrosion inhibitor for zinc, aluminium and alloys

摘要

Parent patent described water-soluble, cross-linked, nitrogenous condensation prods. (I), the viscosity of which in aq. soln. increases with increase in temp. and falls again with decrease in temp., are prepd. by reacting (a) 0.8-30 pts. of a block copolymer of formula (II) R-O-(CH2CH2O)x-(CH2CH(CH3)O)y-(CH2CH2O)x-R, in which R is H(OCH2-C(CH2Cl)H-)n, with n = 0.75-3, -CH2- x = 50-250, y = 20-100 and x:y = 6.5:1-1:15, with (b) 1 pt. of a cpd. with is not 4 basic NH gps. Reaction is in a polar solvent at 20-180 degrees C. In this addn. (I) are used as corrosion inhibitors for Zn, Al or their alloys. (I) give protection against corrosion at all pH levels and in low concn., and can be used in various metal-treating processes. Acid-sensitive alloys, e.g. "Duralumin" (RTM can be protected in strongly acid media (pH 2).