Patent GB-770771-A (GB)
Title: Copolymeric dispersants and lubricant compositions containing them
IPC: C08F220/18
Filed: 1954-04-13
Abstract: Oil-soluble copolymers consisting of (A) a compound having an olefinic double bond and an oil-solubilizing group of 4 to 30 aliphatic carbon atoms and (B) an alpha, beta-unsaturated carboxylic acid in which from 1 to 10 of the carboxyl groups are ester-linked to a poly-1,2-alkylene oxide glycol and from 1 to 10 of the carboxyl groups are ester linked to an alcohol which, in addition to the hydroxy group through which the ester linkage is formed, is substituted by at least one hydroxyl, mercapto, nitro, or amine radical are made by (1) polymerizing an appropriate monomeric mixture, (2) introducing into a homopolymer of (A) the desired radicals or (3) aftertreating a copolymer of (A) and an alpha, beta-unsaturated carboxylic acid.  (A) may be selected from an extensive list including hexene-1, cyclohexene and substituted cyclohexenes, p-octylstyrene, 2-hexadecyl-butadiene-1,3, vinyl n-butyl ether, allyl cyclohexyl ether, methallyl n-hexyl ether, vinyl p-octylphenyl ether, 1-decenyl 2-phenylbutyl ether, vinyl caproate, allyl stearate, methallyl palmitate, dodecyl acrylate, cyclohexyl methacrylate, decyl vinyl acetate, p-tert.-amylphenyl octadecyl maleate, di - 2 - ethylhexyl maleate, di-dodecyl mesaconate and citraconate, and 1-hexadecenyl myristate.  The alpha, beta unsaturated acid may be acrylic, methacrylic, crotonic, tiglic, angelic, alpha-ethylacrylic, betaethyl crotonic, maleic, fumaric, itaconic, glutaconic, citraconic, mesaconic or aconitic.  The poly-(1,2-alkylene oxide) glycols may be diethylene glycol, pentaethylene glycol, nonaethylene glycol, tetra-1,2-propylene glycol, the monobutyl ether of heptaethylene glycol or a polymer of one or more 1,2-alkylene oxides of molecular weight up to 10,000 in which, if desired, at least one of the end groups is replaced by alkoxy or acyloxy groups.  The other esterifying compound may be ethylene glycol, ethanolamine, 1,2-propylene glycol, sorbitol, mannitol, glucose, erythritol, pentaerythritol, dipentaerythritol, tripentaerythritol, nitroethanol, mercaptoethanol, 3-mercapto-propanol, 3,5 - dihydroxycyclohexanol, hydroxyethyl ethylenediamine, 2 - aza - propanol, diethanolamine or 2,2,6,6-tetramethylolcyclohexane. The intermediate or final polymers may be prepared by bulk, solution, or emulsion techniques. Preferably, the polymerization is effected in an inert organic solvent such as benzene, toluene or xylene.  Suitable catalysts are benzoyl, acetyl, di-tert.-butyl or di-tert.-amyl peroxide, tert.-butyl hydroperoxide, or 1,11-azodicyclohexane-carbonitrile or alpha,alpha1-azodiisobutyronitrile.  In examples: (a) maleic anhydride and allyl stearate are copolymerized in toluene in the presence of benzoyl peroxide and the product reacted with dodecyl alcohol and ethanolamine hydrochloride and then with a mixture of polyethylene glycols mainly nonaethylene glycol; (b) the amine in (a) is replaced by dihydroxyethylethylene-diamine hydrochloride; (c) a homopolymer of dodecyl methacrylate is hydrolysed to give a copolymer of dodecyl methacrylate and methacrylic acid, which is esterified with 2-ethyl hexanol, the glycol used in (a) and pentaerythritol; (d) the pentaerythritol in (c) is replaced by tripentaerythritol, and (f) 2-ethylhexyl allyl ether, 3-hydroxypropyl methacrylate and triethylene glycol isobutyl ether methacrylate are polymerized in benzene and toluene.  The copolymers are used as additives to lubricating oils.ALSO:A lubricant composition comprises a major proportion of an oil of lubricating viscosity and a minor proportion of an oil-soluble copolymer consisting of (A) a compound which as an olefinic double bond and an oil-solubilizing group of 4 to 30 aliphatic carbon atoms and (B) an alpha, beta-unsaturated carboxylic acid in which from 1 to 10 of the carboxyl groups are ester-linked to a poly-1, 2 alkylene oxide glycol and from 1 to 10 of the carboxyl groups are ester-linked to an alcohol which in addition to the hydroxyl group through which the ester linkage is formed is substituted by at least one hydroxyl, mercapto, nitro, or amine radical (see Group IV(a).  The composition may also contain pour point depressants, oiliness and extreme pressure agents, antioxidants, corrosion inhibiting agents, blooming agents, thickening agents, detergents, anti-wear agents, or compounds for enhancing the temperature-viscosity characteristics of oils. Oils mentioned are refined Pennsylvania or other paraffin base oil, a refined naphthenic base oil, alkylated waxes, hydrogenated hydrocarbon polymers, the condensation products of chlorinated alkyl hydrocarbons with aryl compounds, polymers of propylene and/or ethylene oxide and acetates of these polymers, di-(2-ethylhexyl) sebacate, tricresyl phosphate, silicate esters, or a mixture of a mineral oil and a synthetic oil.  In examples a highly refined wax-free base oil, of V.1.85 and derived from California waxy crude is compounded with the following copolymers-allyl stearatedodecyl maleatedodecyl 2-aminoethylmaleate-dodecyl (polyethylene glycol) maleate, allyl searate-dodecyl maleatedodecyl (dihydroxyethyl ethylenediamine) maleate-dodecyl (polyethylene glycol) maleate, dodecyl methacrylate-methacrylic acid-polyethylene glycol methacrylatetripentaerythritol or pantaerythritol monomethacrylate, 2-ethylhexyl allyl ether-3-hydroxypropyl methacrylate-isobutyl ether triethylene glycol methacrylate, and dodecyl methacrylate-polyethylene glycol methacrylate-2-aminoethyl methacrylate.