Patent GB-695309-A (GB)
Title: Water-resistant greases
Filed: 1951-01-25
Abstract: Alkyl or alkenyl substituted aliphatic dicarboxylic acids containing at least two carbon atoms between the carboxyl groups or anhydrides thereof, the alkyl or alkenyl substituent having from 5-36 carbon atoms, may be prepared by reacting olefins containing 5-36 carbon atoms with an unsaturated dicarboxylic acid containing at least two carbon atoms between the carboxyl groups or an anhydride thereof, such as maleic anhydride or acid, fumaric acid, citraconic anhydride or acid, itaconic anhydride or acid, mesaconic acid, glutaconic anhydride or acid and methyl itaconic anhydride or acid.  Preferably the olefin used should have a boiling-point above 250 DEG  C. but not much in excess of 400 DEG  C.  Suitable olefins are those obtained by the vapour phase cracking of paraffin wax at about 560 DEG  C.  The alkenyl dicarboxylic acids and anhydrides so formed may be hydrogenated to give the alkyl dicarboxylic acids and anhydrides. The alkyl or alkenyl acids may be converted into amides by reaction with ammonia or a mono-, di- or polyamine.  The preferred amines may contain 2 to 18 carbon atoms, such as ethylene diamine, diethylene triamine, triethylene tetramine, 1-methyl-ethylene diamine, 1-ethyl-ethylene diamine, propylene diamine, butylene diamine, trimethyl trimethylene diamine, tetramethylene diamine, diaminopentane, pentamethylene diamine, diaminohexane, hexamethylene diamine, heptamethylene diamine, diamino-octane, decamethylene diamine, and higher homologues up to 18 carbon atoms, the phenylene diamines, methyl-, ethyl-, propyl- and butylphenylene diamines, naphthalene diamines and the alkylated naphthalene diamines. Mono-amides may be formed by reacting the appropriate dicarboxylic acids with ammonia, and these products may be further condensed with a diamine.  Esters of the above acids are obtainable by treating a dicarboxylic acid ester with an alkali metal alcoholate in alcohol to replace a hydrogen atom on the a -carbon atom and reacting this product with an alkyl halide to introduce the alkyl group.  Acid esters may be prepared by reacting equimolecular quantities of the substituted acid or anhydride with an alcohol containing 1-24 carbon atoms, or by refluxing equimolecular quantities of an alkali metal alcoholate and the substituted acid or anhydride in the presence of a diluent such as benzene.  In typical processes, (1) an alkenyl succinic acid is prepared by heating maleic anhydride in an autoclave with a distillate fraction of vapour-phase cracked wax boiling between 280 DEG  and 340 DEG  C., of bromine No. 36 and olefin content about 60 per cent, the residue, after vacuum distillation to remove unreacted materials, being converted by hydration to the free alkenyl succinic acid; (2) nonenyl succinic anhydride is prepared by heating 4 mols. of nonylene with 1 mol. of maleic anhydride in a closed system; the anhydride so formed is condensed with ethylene diamine at room temperature.  Other specified products are dodecenyl-, hexadecenyl-, and octadecenyl succinic acids, tridecyl-, pentadecyl- and heptadecyl succinic acids, octadecyl succinic anhydride, octadecenyl succinamic acid, dodecenyl succinamic anhydride, the methyl esters of octadecenyl succinic acid, the 2-ethyl-hexyl esters of hexadecyl succinamic acids and the dodecenyl esters of decenyl succinic acid.  The products may be used as additives in lubricating greases (see Group III). Specification 395,193 is referred to.ALSO:A grease composition comprises a lubricating oil (other than a lubricating oil containing free hydroxy or mercapto groups), 1 to 20 per cent by weight of an inorganic gel, 0.2 to 10 per cent by weight of a non-metallic aliphatic hydroxy or mercapto compound containing at least 8 carbon atoms in the molecule and 0.2 to 10 per cent by weight of an alkyl or alkenyl substituted aliphatic dicarboxylic acid containing at least two carbon atoms between the carboxyl groups or an anhydride, amide or ester of such a compound, the alkyl or alkenyl substituent having from 5-36 carbon atoms (the "secondary additives," for the preparation of which see Group IV(b)).  The preferred secondary additives are the succinic and succinamic acids having alkyl or alkenyl substituents with between 10 and 24 carbon atoms such as dodecenyl-, hexadecenyl- and octadecenyl succinic acids, tridecyl-, pentadecyl-and heptadecyl-succinic acids, octadecyl succinic anhydride, octadecenyl succinamic acid, and dodecenyl succinamic anhydride.  The esters are preferably those of aliphatic alcohols having from 1 to 24 carbon atoms such as the methyl esters of octadecenyl succinic acid, the 2-ethylhexyl esters of hexadecyl succinamic acids and the dodecenyl esters of decenyl succinic acid.  Specified lubricating oils and non-metallic hydroxy- or mercapto-compounds containing at least 8 carbon atoms in the molecule are as set forth in the parent Specification.  The inorganic gels which may be used include those set forth in the parent Specification and, in addition, natural or synthetic clays treated with organic cationactive surface-active agents such as quaternary ammonium salts.  Swelling clays such as montmorillonite (e.g. Wyoming bentonite) or hectorite may be dispersed in water to form a hydrosol and 10-50 per cent of the weight of the clay of a quaternary ammonium salt such as dicetyl dimethyl ammonium chloride may be added to form a hydrogel.  This may be directly incorporated into an oil by milling with simuutaneous or subsequent removal of water by heating.  The greases are prepared as set forth in the parent Specification. In examples, the following lubricating grease compositions are described; (1) mineral lubricating oil, 5 per cent of silica alcogel (prepared from the hydrogel by displacement of water), 2.4 per cent of the triglyceride of 12-hydroxystearic acid and 2.4 per cent of octadecenyl succinic acid; (2) mineral oil, 5 per cent of silica-alumina alcogel, 2 per cent of the triglyceride of 12-hydroxystearic acid and 1 per cent of octadecenyl succinic acid; (3) 92 parts by weight of mineral oil, 5 parts by weight of inorganic gel (a) alumina, (b) silica (c) silica) 1 part by weight of a succinic acid derivative [(a) methyl ester of octadecenyl succinic acid, (b) hexadecenyl succinamic acid, (c) dodecenyl succinic anhydride] and 2 parts by weight of an aliphatic hydroxy compound [(a) 12-hydroxystearic acid, (b) 1, 2-decamethylene glycol (c) stearyl alcohol]; (4) mineral oil, 6 per cent by weight of silica alcogel, 1 per cent of glycerol monostearate and 1 per cent of octadecenyl succinic acid; and (5) mineral lubricating oil, 6 per cent by weight of silica gel, 1 per cent by weight of dimethyl dioctadecyl ammonium chloride, 2 per cent of the triglyceride of 12-hydroxy stearic acid and 1 per cent of octadecenyl succinic acid. Specification 395,193, [Group IV], and U.S.A.  Specifications 2,260,625 and 2,449,253 also are referred to.