Abstract:
A process for the production of a substantially anhydrous lubricating composition comprising a mixture of metal salts of acetic acid and a C7 to C10 monocarboxylic acid, and lubricating oil, consists in heating the mixture to 250-350 DEG F., maintaining the proportion by weight of the said metal salts in the range of 20-50%, homogenizing in the range 80-150 DEG F. with the rate of shear in the range 100,000 to 500,000 reciprocal seconds, diluting with further amounts of lubricating oil, thus giving a concentration of 4-10 wt. per cent of metal salts and homogenizing in the range 80-150 DEG F., with the rate of shear in the range 100,000 to 750,000 reciprocal seconds, to give a fluid product of viscosity 80-200 S.S.U. at 210 DEG F. and said to be of improved stability. The lubricating oil has an initial viscosity in the range 55-100 S.S.U. at 210 DEG F. and a V.I. of 40-100; the molecular ratio of acetic to C7-C12 acid is in the range of 10 : 1 to 25 : 1. It is preferred to form the said mixture of salts in the lubricating oil; the preferred metal is calcium, and it is preferred to homogenize the product containing 20-50 wt. per cent of said salts in at least two stages with intermediate storage between stages. Specific examples use a commercially available mixture of 28% caprylic, 56% capric and 16% lauric acid as the source of C7 to C10 acid, hydrated lime as a source of calcium and 0.6% (based on the composition prior to dilution) of phenyl a -naphthylamine. The lubricating oils of the examples are:- a hydrofined coastal distillate or acid-treated or hydrofined oils derived from naphthenic coastal crude; other oils used may be synthetic, e.g. of the hydrocarbon, hydrocarbon polymer, ester (such as di-2-ethylhexyl sebacate or di-C8- or -C10-oxo azelates), complex ester (e.g. of glycols, dicarboxylic acids and alcohols or monocarboxylic acids), formal, mercaptal, polyalkene oxide, or silicone types. The compositions of this invention are said to be useful for lubricating marine diesel engines.
Abstract:
A lubricating grease comprises lubricating oil thickened with the aluminium soap of a mixture of acids consisting of 87-93 per cent. by weight of a soap-forming fatty acid and 7-13 per cent. of a non-aromatic alicyclic dicarboxylic acid having a molecular weight of 300-700. The lubricating oil may be mineral lubricating oil or a synthetic lubricant such as oxyalkylene polymers (e.g. propylene oxide polymers, ethylene oxide-propylene oxide copolymers, trimethylene glycol polymers and ethylene glycol-trimethylene glycol copolymers), silicone fluids, organic phosphates (e.g. tricresyl, trioctyl, diphenylcresyl or diphenyloctyl phosphate), polymerized olefins, polyvinyl caprylate, and esters of dicarboxylic acids (e.g. di(2-ethylhexyl) sebacate and di(3-methylheptyl) adipate). Soap-forming fatty acids mentioned are the saturated and unsaturated fatty acids and the substituted fatty acids such as ricinoleic, licanic and 12-hydroxystearic acids. Such fatty acids may be derived from animal, fish and vegetable fats and oils or the corresponding hydrogenated oils. The non-aromatic alicyclic dicarboxylic acids may be monocyclic or polycyclic and may be prepared by the dimerisation of unsaturated soap-forming fatty acids. The mixed aluminium soaps may be formed in the presence of lubricating oil, for example by saponifying the mixed acids with aluminium hydroxide in presence of lubricating oil. Alternatively the mixed soaps may be first prepared and then added to the lubricating oil. The lubricating grease may contain other ingredients such as inorganic colloidal gelling agents (e.g. silica, alumina, magnesia, lime, magnesium silicate, aluminium silicate, bariumoxide, copper sulphide, bentonite, hectorite and synthetic clay-like materials), film-forming anticorrosion agents (e.g. sodium dichromate or sodium nitrite), cationic surface-active agents (e.g. amines, amides and quaternary ammonium compounds, particularly octadecylamine, the partial oleic acid amide of tetraethylene pentamine and dimethyl diheptadecyl ammonium chloride) and antioxidants (e.g. phenyl-alphanaphthylamine and alkylated cresols). In the examples, greases are described consisting of mineral lubricating oil and the mixed aluminium soaps of (a) hydrogenated fish oil fatty acids and dimerized linolenic acid or (b) 12-hydroxy stearic acid and 1, 3-di(6-carboxyhexyl) 4, 5-diheptylcyclohexane.