Patent GB-640578-A (GB)
Title: Improved lubricating compositions and preparation of co-polymers for use therein
IPC: C08G75/12
Filed: 1947-10-06
Abstract: Copolymers suitable for use as lubricants are made by heating an alkylene oxide or glycol with an alkylene sulphide or thioglycol in the presence of a catalyst.  Specified alkylene oxides are ethylene, propylene, butylene, amylene, sym.-dimethyl-ethylene, sym.-diethyl-ethylene, 2,2-dimethyl-ethylene, 2,2-diethyl-ethylene, 2-methyl-21-ethyl- and 2-methyl-21-isopropyl-ethylene oxides; glycidyl methyl ether, ethyl ether, b -methoxyethyl ether and n-decyl ether; glycidyl formate, acetate, propionate and butyrate; glycidylamine and its methyl, ethyl, propyl, isopropyl, butyl, dimethyl, diethyl and methylethyl derivatives; epichlorohydrin, epibromohydrin, epiiodohydrin.  Specified glycols include ethylene, propylene, butylene, diethylene, triethylene and tetraethylene glycols; methyl-, dimethyl-, trimethyl-, tetramethyl-, pentamethyl-, and hexamethyl-propane-1,3-diols and the corresponding ethyl, propyl, isopropyl, butyl, hexyl and heptyl analogues; 1-methyl-2-ethyl-, 2-methyl-2-ethyl-, 1-methyl-3-ethyl-, 2-methyl-2-butyl-and 2-methyl-3-butyl-propane-1,3-diols; hexamethylene, heptamethylene, octamethylene, nonamethylene, decamethylene and dodecamethylene glycols and their alkyl derivatives.  Alkylene sulphides and thioglycols specified are ethylene, propylene, butylene, isobutylene and amylene sulphides; 2-mercapto-ethyl and propyl alcohols, 3-mercapto-propyl alcohol and 4-mercapto-butyl alcohol; ethylene, propylene, butylene, trimethylene and hexamethylene dimercaptans. Suitable catalysts for copolymerizing alkylene oxides with alkylene sulphides are boron trifluoride, potassium and sodium hydroxides, stannic, aluminium, and ferric chlorides, and for alkylene glycols with alkylene thioglycols are sulphuric, phosphoric and p-toluenesulphonic acids, iodine and hydrogen iodide.  Polymerization may be effected in liquid, solution, emulsion or gaseous phases. Suitable diluents are methane, ethane, propane, butane, dihydronaphthalenes, cycloheptane, 2-methyl-octane and -nonane, 2,6-dimethyloctane, 2,2,3 - trimethylpentane, 2 - methyl - 3 - ethylpentane, 2,4-dimethylheptane, 4-ethylheptane, dihexyl and 2,4,5,7-tetramethyloctane.  After removal of catalyst, the products are dehydrated and, if desired, decolourized by percolation in solution through Fuller's earth or by hydrogenation.  The copolymers may be partially or completely etherified or esterified, simultaneously with or subsequent to polymerization.  They may also be reacted with ammonia or amines to introduce amino end-groups.  The copolymers may be used as extreme pressure additives to lubricants, e.g. mineral oils, polymers of alkylene oxides and alkylene glycols and bis-(2-ethylhexyl sebacate).  Oxidation inhibitors, e.g. 1,2-dihydroxybenzene, amines and aminophenols, anti-corrosion agents, e.g. organic acids capable of forming soaps, gelling agents, e.g. metallic soaps, water, emulsifying agents and graphite may be added.ALSO:Copolymers suitable for use as lubricants are made by heating an alkylene oxide or glycol with an alkylene sulphide or thioglycol in the presence of a catalyst (see Group IV (a)).