Patent GB-768690-A (GB)
Title: Copolymeric dispersants and lubricant compositions containing them
IPC: C10M145/12
Filed: 1954-03-02
Abstract: Copolymers of (A) a total of from 75 to 97 mol. per cent of at least one olefinically unsaturated polymerizable compound having an oil-solubilizing group of 4 to 30 aliphatic carbon atoms; (B) at least one lower aliphatic alpha, beta-unsaturated monocarboxylic acid, and (C) at least one ester of a poly-1,2-alkylene glycol and a lower aliphatic alpha, beta-unsaturated monocarboxylic acid are made (1) by polymerizing a mixture of (A), (B) and (C) in the presence of a catalyst; (2) introducing into a homopolymer of (A), units of (B) and (C); or (3) introducing into a copolymer of (A) and (B), units of (C). (A) may be selected from an extensive list including hexene-1, cyclohexene and substituted cyclohexenes, p-octylstyrene, 2-hexadecylbutadiene-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.  (B) may be derived from acrylic, methacrylic, crotonic, tiglic, angelic, alpha-ethylacrylic, alpha - methyl crotonic, alpha - ethylcrotonic, beta-ethylcrotonic, alpha-butylcrotonic, hydrosorbic, alpha-ethylhydrosorbic, or alpha-propylhydrosorbic acid.  (C) is an ester of an acid as in (B) and a polyglycol such as 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 copolymers or polymer intermediates are prepared by conventional methods, e.g. bulk, solution or emulsion, in the presence of catalysts such as benzoyl, acetyl, di-tert. butyl or di-tert. amyl peroxide, tert. butyl hydroperoxide, 1,11-azodicyclohexane-carbonitrile, or alpha, alpha1azodiisobutyronitrile.  In examples: (a) a copolymer of dodecyl methacrylate, methacrylic acid and polyethylene glycol monomethacrylate is made by partially hydrolysing a homopolymer of dodecyl methacrylate and reacting with a mixture of polyethylene glycol compounds consisting of a major proportion of nonaethylene glycol of average molecular weight about 400; (b) a copolymer of 2-ethylhexyl allyl ether, acrylic acid and tetra-1,2-propylene glycol acetate acrylate is made by preparing a copolymer of 2-ethylhexyl allyl ether and acrylic acid by reacting the monomers in benzene in the presence of benzoyl peroxide and reacting it with tetra-1,2-propylene glycol monoacetate; (c) a copolymer of 2-ethyl-hexyl acrylate, dodecyl acrylate, methacrylic acid and the monooctyl ether of tridecaethylene glycol is made by reacting a copolymer of 2-ethylhexyl acrylate and methacrylic acid with dodecanol and then with the monooctyl ether of tridecaethylene glycol, and the following copolymers are made by bulk polymerizing the monomers in the presence of benzoyl peroxide, lauryl methacrylate and methacrylic acid and the methacrylate of the lauryl monoether of polyethylene glycol, or the methacrylate of octadecyl monoether of polyethylene glycol, or the methacrylate of the methyl monoether of polyethylene glycol or the methacrylate of polypropylene glycol, tridecyl methacrylate and methacrylic acid and the methacrylate of the tridecyl monoether of polyethylene glycol, octadecyl methacrylate and methacrylic acid and the methacrylate of the lauryl monoether of polyethylene glycol, and (alkylphenoxy)-ethyl methacrylate and methacrylic acid and the methacrylate of the lauryl monoether of polyethylene glycol.  The copolymers are used as additives for lubricating oils.ALSO:A lubricant composition comprises a major proportion of an oil of lubricating viscosity and a minor proportion of an oilsoluble copolymer of (a) a total of from 75 to 97 mole per cent of an olefinically unsaturated polymerizable compound having an oil solubilizing group of 4 to 30 aliphatic carbon atoms; (b) at least one monomer unit of a lower aliphatic alpha, beta-unsaturated, monocarboxylic acid, and (c) at least one monomer unit of an ester of a polyoxy-1, 2-alkylene glycol and a lower aliphatic, alpha; beta-unsaturated monocarboxylic acid (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 the following copolymers are added to a solvent-refined California base oil of viscosity 65 S.S.U. to 110 S.S.U. at 210 DEG F.-lauryl methacrylate and methacrylic acid and the methacrylate of lauryl monoether of polyethylene glycol or the methacrylate of octadecyl monoether of polyethylene glycol, or the methacrylate of methyl monoether of polyethylene glycol or the methacrylate of polypropylene glycol, octadecyl methacrylate/methacrylic acid/and the methacrylate of lauryl monoether of polyethylene glycol, and (alkylphenoxy)-ethyl methacrylate/methacrylic acid/and the methacrylate of lauryl monoether of polyethylene glycol.  The function of the copolymer is that of a detergent.