Patent GB-867544-A (GB)
Title: Improvements in or relating to molybdenum-containing lubricant additives
IPC: C07F11/00
Filed: 1957-06-28
Abstract: Organic nitrogen base salts of a reduced phosphomolybdic acid containing tetravalent molybdenum are prepared by reducing phosphomolybdic acid or an organic nitrogen base salt thereof, by heating at a temperature of at least 100 DEG C. with an organic reducing agent as hereinafter defined until the product assumes a deep blue colour and if the product obtained is not in the form of a salt of an organic nitrogen base, neutralising with such a base. The organic reducing agents are organic nitrogen bases and non-basic organic compounds, all containing active (Zerevitinoff) hydrogen, esters and ethers.  The organic nitrogen bases may be used in excess as reducing and neutralising agents.  Specified nitrogen bases utilisable in both connections include oleylamine, dehydroabietylamine, di-2-ethyl hexylamine, a mixture of NC8-18 hydrocarbon substituted propylene diamines, N-aminopropyl morpholine, amino alcohols such as oleyl oxyethyl glyoxalidine and dialkyl thioureas such as di-oleyl thiourea.  A number of these bases are used to prepare the phosphomolybdic acid salts used as starting materials.  Numerous other organic reducing agents are specified including higher alcohols and diols, polyglycols and esters and ethers thereof, benzyl butyl phthalate and di-octyl adipate.  The products are lubricant additives (see Group III).ALSO:A lubricant-compatible additive which is a reduced phosphomolybdic acid, or organic nitrogen base salt thereof, containing molybdenum in tetravalent form is prepared by reducing phosphomolybdic acid or an organic nitrogen base salt thereof, by heating to a temperature of at least 100 DEG C. with an organic reducing agent as hereinafter specified until the product assumes a deep blue colour.  The organic reducing agents are non-basic organic compounds, including alcohols, diols and polyglycols, and organic nitrogen bases, all containing active (Zerevitinov) hydrogen, and esters and ethers.  The reducing agents are preferably oil-soluble or themselves lubricants and may be used in excess.  When the product is not already in the form of an organic nitrogen base salt it is preferably neutralised with such a base and thereby stabilized.  The additives may be used in mineral or synthetic lubricating oils including higher alcohols, diols, esters, ethers and polyglycols and their ether and ester derivatives, and in amounts ranging from 0.1 to 40% by weight of the total lubricant.  In order to obtain a lubricant resistant to extreme pressure, sulphur or a suitable sulphur compound may be introduced into the lubricant, whereby in use molybdenum disulphide may be formed, and if desired the necessary sulphur may be contained in the reducing compound used in making the additive.  Suitable sulphur compounds are sulphurised unsaturated fatty acids and their esters, fatty alcohols, amines and olefinic polymers, organic sulphides, diol xanthates, dialkyl thioureas and organic derivatives of thio and di-thiophosphoric acid, e.g. zinc salt of dihexyl dithiophosphate.  In Examples: (1) 4% of phosphomolybdic acid is added to each of the following: ethyl hexanediol, n-octadecanol, a mixture of abietyl alcohols (Abitol) a mixture of higher fatty alchohols (Eutanol), dehydroabietylamine, di-octyl adipate, benzyl butyl phthalate, a mixture of higher fatty primary amines, a mixture of higher fatty secondary amines, a mixture of N-higher alkyl propylene diamines, and a polyalkylene glycol, or 30% of phosphomolybdic acid is added to each of the following: Eutanol, Abitol, and certain di-esters (Flexols), and the solutions are heated at 125-140 DEG C. until they turn a deep blue colour; (2) phosphomolybdic acid salts of dehydroabietylamine, dioleylamine, N-aminopropylmorpholine and a mixture of C16-C18 fatty primary amines are each heated at 150 DEG C. in Eutanol, dibutoxytetraglycol or a polyethylene glycol (M.W. 500) to give stable deep blue solutions of additive. Other examples of suitable reducing agents are given including amino alcohols such as oleyloxy ethyl glyoxalidine.