GB774085A - Polyamide grease composition - Google Patents

Abstract

Polyamides are obtained by reacting a dicarboxylic acid with a diamine, the mol. ratio of acid to diamine being less than 1, reacting the product with a sufficient amount of a monocarboxylic acid to neutralize the terminal amine groups. Thus the product may be of general formula: R2-CO-NH-R-NH-(CO-R1-CO -NH-R-NH-CO-R1-CO-NH -R-NH)2-CO.R2, where R is a polymethylene or substituted polymethylene group of 2-30 carbon atoms and R1 is a methylene group or a polymethylene or substituted polymethylene group of 1-52 carbon atoms, R2 is an aliphatic, alkaryl or aralkyl group of 2-30 carbon atoms and Z is 1.5-20. R and R1 may be, for example, methylene, dimethylene, trimethylene, hexamethylene, octamethylene, octadecylmethylene and radicals derived from petroleum hydrocarbons, e.g. white oil, petroleum wax and olefin polymers. R2 may be propyl, propenyl butyl, hexyl, octyl, octenyl, nonyl, decyl, decenyl, dodecyl, dodecenyl, tetradecyl, tetradecenyl, hexadecyl, octadecyl, eicosyl, triacontyl, capryl, octadecenyl and radicals derived from petroleum hydrocarbons, e.g. white oil, petroleum wax and olefin polymers, e.g. polypropylene and polybutene. In the example the preparation of a polyamide by the reaction of the reaction product of 1 mol. of hexamethylene diamine and 0.5 mol. of adipic acid with 1 mol. of stearic acid is described. Specifications 774,084 and 774,086 are referred to.ALSO:A grease composition comprises a lubricating oil thickened to a grease consistency with a compound obtained by reacting a dicarboxylic acid with a diamine, the mole ratio of acid to diamine being less than 1, and reacting the product with a sufficient amount of a monocarboxylic acid to neutralize the terminal amine groups. Thus the product may be of general formula: R2 - CO - NH - R - NH - (CO - R1 - CO - NH - R - NH - CO - R1 - CO - NH - R - NH)Z - CO - R2, where R is a polymethylene or substituted polymethylene group of 2-30 carbon atoms and R1 is a methylene group or a polymethylene or substituted polymethylene group of 1-52 carbon atoms, R2 is an aliphatic alkayl or aralkyl group of 2-30 carbon atoms and Z is 1.5-20. R and R1 may be, for example, methylene, dimethylene, trimethylene, hexamethylene, octamethylene, octadecylmethylene and radicals derived from petroleum hydrocarbons, e.g. white oil, petroleum wax and olefin polymers. R2 may be propyl, propenyl, butyl, hexyl, octyl, octenyl, nonyl, decyl, decenyl, dodecyl, dodecenyl, tetradecyl, tetradecenyl, hexadecyl, octadecyl, eicosyl, triacontyl, capryl, octadecenyl and radicals derived from petroleum hydrocarbons, e.g. white oil, petroleum wax and olefin polymers, e.g. polypropylene and polybutene. In the example, a solvent-refined naphthenic base oil is thickened to form a grease with a product prepared by reacting the reaction product of 1 mole of hexamethylene diamine and 0.5 moles of adipic acid with 1 mole of stearic acid. Lubricating oils referred to are naphthenic base, paraffin base and mixed base oils; other hydrocarbon oils such as those derived from coal products; and synthetic oils e.g. alkylene polymers, alkylene oxide polymers, dicarboxylic acid esters, liquid phosphorus esters, alkyl benzene polymers and silicon polymers, e.g. silicates and polysiloxanes. Examples of synthetic oils are given. Specifications 774,084 and 774,086 are referred to.