Patent GB-881798-A (GB)
Title: Improved grease compositions
IPC: C08F8/00
Filed: 1959-11-26
Abstract: A grease composition comprises a base oil thickened to a grease consistency with an inorganic or organic thickener, and containing a minor proportion of an oil-soluble copolymer derived from (a) a diester of an a -b  unsaturated dicarboxylic acid and a C8-C20 aliphatic alcohol, (b) an ester of a C1-C6 monocarboxylic acid and an unsaturated alcohol containing a vinyl group and (c) a partial ester of an a -b  unsaturated dicarboxylic acid and a C1-C20 aliphatic alcohol, which partial ester has had its remaining carboxyl group reacted with a C2-C6 alkylene oxide.  The base oil may be of animal, vegetable or mineral origin, or it may be a synthetic oil, such as an oxidized mineral oil or an ester-based oil.  Thickeners mentioned are carbon black, hydrocarbon polymers, activated clays or silicas, or mixtures thereof, alkali or alkaline earth metal soaps of fatty acids or hydroxy fatty acids and soap-salt complexes.  The soap-salt complexes may be prepared from metal soaps of carboxylic acids containing more than 6 carbon atoms per molecule and metal salts of carboxylic acids containing up to 6 carbon atoms per molecule.  These complexes may be formed separately, if desired, in the presence of a base oil, or they may be formed in situ during the preparation of the grease composition.  The grease composition may also contain extreme pressure additives, anti-corrosion agents, dispersants and tackiness agents.  In the examples, grease compositions consist of mineral lubricating oil thickened with sodium stearate or calcium acetate/calcium caprylate complex and containing a copolymer of fumarates of C8/C10 and/or C16/C18 coconut alcohols, vinyl acetate and ethoxylated monomaleate of C8/C10 coconut alcohols (ethoxylated with 5, 10 or 20 mols. of ethylene oxide).  In each case, the thickener is formed in situ by neutralization of the free acid or acids with metal base.  The effect of omitting the ethoxylated ester from the copolymer is described.ALSO:An ingredient of a grease composition (see Group III) is an oil-soluble copolymer derived from (a) a diester of an a -b  unsaturated dicarboxylic acid and a C8-C20 aliphatic alcohol, (b) an ester of a C1-C5 monocarboxylic acid and an unsaturated alcohol containing a vinyl group and (c) a partial ester of an a -b  unsaturated dicarboxylic acid and C1-C20 aliphatic alcohol, which partial ester has had its remaining carboxyl group reacted with a C2-C6 alkylene oxide.  In the examples, copolymers are mentioned which are derived from fumarates of C8/C10 and/or C10/C18 coconut alcohols, vinyl acetate and ethoxylated monomaleate of C8/C20 coconut alcohols (ethoxylated with 5, 10 or 20 mols. of ethylene oxide).ALSO:Ethoxylated alkyl maleates are prepared by reacting maleic anhydride with a C1-C20 alkanol to produce a partial ester, then adding one mol of ethylene oxide per mol of partial ester in the presence of soda, and finally by continuing to fix ethylene oxide on to the partial ester molecules in the presence of a boron fluoride/diethyl ether complex.  In examples, the esters prepared are ethoxylated monomaleates of C8/C10 coconut alcohols (ethoxylated with 5, 10 or 20 mols. of ethylene oxide.)