Low pH-buffered silicon/silicate antifreeze concentrates

Claim 1

An antifreeze composition concentrate comprising of: (i) an alcohol, (ii) a corrosion inhibiting amount of an organosiloxane/silicate polymer, that is soluble and stable against gelation in the antifreeze composition concentrate, and that contains as its essential components from 0.1 to 99.9 parts by weight of A and from 0.1 to 99.9 parts by weight of B or C, or mixtures of B and C, wherein the individual components of the polymer comprise: (A) a lyophyllic, organofunctionally-modified siloxane portion of the polymer and defined as a distribution of species represented by the empirical formula: ##STR3## where Y represents a lyophyllic organofunctional moiety selected from a group consisting of polyethyleneoxy containing species, hydroxy containing species, saponified carboxy containing species, saponified phosphate or phosphonate ester containing species, saponified sulfonate containing species, or mixtures thereof; wherein a is an integer having a value of 1 to 20 inclusive, b is an integer having a value of 1 to 3 inclusive, c is an integer having a value from 0 to 2 inclusive, d is an integer having a value from 0 to 3 inclusive and e is an integer having a value from 1 to 4 inclusive, the value for e being equal to the sum of b, c and d; R is a monovalent hydrocarbon radical free of olefinic unsaturation; and, Z represents a hydrolyzable moiety attached to silicon consisting of at least one member selected from a group consisting of OR' and NR' 2 wherein R' is selected from the group consisting of hydrogen, monovalent hydrocarbon radicals, and substituted monovalent hydrocarbon radicals; said siloxane portion being present in an amount sufficient to solubilize and stabilize against gel formation said orgnosiloxane/silicate polymer, (B) an inorganic silicate described as a distribution of species represented by the empirical formula: ##STR4## wherein M is a monovalent cation that forms a water soluble silicate, selected from the group consisting of sodium, potassium, lithium, rubidium and tetraorganoammonium cations and where x has a value of from 1 to 4 inclusive, y has a value from 0 to 3 inclusive and p has a value from 1 to 4 inclusive which is equal to the sum of x and y; and (C) an organic silicate ester encompassed by the formula: Si(OR).sub.4 wherein R is selected from the group consisting of alkyl, aryl, alkoxyalkyl, alkoxyaryl and mixtures thereof, and (iii) a buffer selected from the group consisting of ammonium borate, alkanolamine and alkali metal borate, alkaline earth metal borates, tetraalkyl and tetraaryl-ammonium borates and, mixtures of the above borates and ammonium phosphate, alkanolamine phosphates and tetraalkyl and tetraaryl-ammonium phosphates, and phosphate mixtures thereof, ammonium and amine benzoates and substituted benzoates, and ammonium and amine salts of dibasic acids having 6 to 20 carbons, said buffer being present in an amount of between about 1 and about 5 wt. percent, based on the weight of the concentrate, and yielding a reserve alkalinity from about 10 to 75; said concentrate having a pH range in the concentrate of 5.8 to about 7.5, with the proviso that essentially no alkali metal phosphate is present.

Claim 16

A method of cooling an internal combustion engine with the concentrate of any of claims 1 through 14 which comprises, without regard to sequence, the steps of: (a) diluting the concentrate with water and/or alcohol to produce a working antifreeze, and (b) adding the working antifreeze to an automobile engine cooling system.