GB704023A - Improvements in and relating to the preparation of lubricating greases - Google Patents

Abstract

Lubricating grease is prepared by rapidly heating a mixture of an organic liquid lubricating base and a gelling agent to about the solution temperature, rapidly cooling to a temperature below the solution temperature and subjecting the mixture to a shearing action, recycling a portion of the mixture to subject it again to a shearing action together with a further amount of the heated and rapidly cooled mixture, and withdrawing and cooling the non-recycled portion. The process may be a continuous or a batch process. Gelling agents referred to are the lithium, sodium, potassium, caesium, calcium, strontium, barium, cadmium, zinc, lead and cobalt soaps or salts prepared from higher fatty or hydroxy fatty acids or their glycerides, acids produced by oxidation of petroleum oil and waxes, rosin acids, tall oil acids, abietic acids, naphthenic acids and petroleum sulphonic acids. Fatty acids and glycerides specified are capric, lauric, myristic, palmitic, stearic, arachidic, behenic, lignoceric, myristoleic, palmitoleic, oleic, linoleic, ricinoleic, and erucic acids, cottonseed oil, palm oil, and hydrogenated fish oil fatty acids, and lard, beef, rapeseed, palm, menhaden and herring oils; hydroxy fatty acids such as dimethyl hydroxy caprylic, dimethyl hydroxy capric, hydroxy physetoleic, ricinoleic, 12-hydroxystearic, 9, 10-dihydroxystearic, 4-hydroxypalmitic, linusic, sativic, dihydroxygadoleic, dihydroxybehenic and quince-oil acids, castor oil and hydrogenated castor oil; amine soaps such as triethanolamine oleate, and mixtures of soaps and organic or inorganic aerogels, for example silica or alumina aerogel, nylon or cellulose fibres, may also be used. Lubricating bases referred to are mineral or synthetic oils, such as polymerized olefins, organic esters, for example, di(2-ethyl-hexyl) sebacate, dioctyl phthalate and triethylhexyl phosphate, polymeric tetrahydrofuran, poly alkyl silicone polymers, for example, dimethyl silicone polymers, alkylated aromatics, such as naphthalene substituted by high molecular weight paraffinic hydrocarbon radicals; fatty oils such as castor or lard oil may be mixed with these oils. Optional additives mentioned are stabilizing agents such as alkylene glycol and or alkylene thio glycol polymers and their monoester and ether derivatives; other soaps or salts, such as aluminium soaps, alkali and alkaline earth metal acetates, hydroxybenzoates, alpha- and betahydroxypropionates, gamma-hydroxyvalerates, calcium salt of an alkyl phenol-formaldehyde condensation product and zinc dibutyl-dithiocarbamate; oxidation inhibitors such as N-butyl, paraphenylene diamine, alpha or beta naphthylamine, phenyl-alpha or beta naphthylamine, alpha-alpha, beta-beta dinaphthylamine, diphenylamine, tetramethyldiamino - diphenylmethane, petroleum alkyl phenols, and 2,4-ditertiary butyl-6-methyl phenol; corrosion inhibitors such as hexylamine, octylamine, decylamine, dodecylamine, octadecylamine and alkyl substituted oxazolines and oxazoline salts of fatty acids; extreme pressure agents such as organic phosphates, thiophosphates and phosphites, diphenyl, dicresol and dibenzyl sulphides, methyl butyl diphenol sulphide, diphenyl and dicresol selenides, sulphurized oils or esters such as sperm oil, joboba oil, sulphurized olefines from the dehydrogenation or cracking of wax, sulphurized and phosporized fatty oils, acids, esters and ketones, esters of phosphoric or phosphorus acids with sulphurized hydroxy fatty acids, chlorinated hydrocarbons such as chlorinated paraffins, aromatic hydrocarbons, terpenes, mineral lubricating oils, chlorinated esters; and urethanes, allophanates, carbazides, carbazones, rubber, polyisobutylene, polyvinyl esters, voltolized paraffin wax, unsaturated polymerized esters, and stearic and oleic acids.