Patent GB-960512-A (GB)
Title: Stabilised polyols
Inventor: JOHN WILLIAM DAVID
IPC: C09K15/32
Filed: 1962-05-08
Abstract: Substituted phenothiazines wherein at least one of the hydrogen atoms in positions 1-4 or 6-9 inclusive is replaced by the group COOX (wherein X is Li, Na, K, or NH+4); or the hydrogen attached to the nitrogen atom in position 10 is replaced by a polyethylene glycol group containing not less than 20 CH2CH2O units are used to stabilize polyols having 4 to 100 CH2CH2O units and which are polyols of ethylene and propylene oxides which may be glycol, ether or ester derivatives. Polyol compositions containing 5% by weight of a polyethylene glycol (MW. 600) and 95% by weight of water are stabilized by (1) an N-substituted phenothiazine compound having a polyoxy-alkylene residue of 27 CH2CH2O units, (2) phenothiazine 2:8 dicarboxylic acid and (3) phenothiazine 1 carboxylic acid. Phenothiazine 2:8 dicarboxylic acid is prepared by first reacting 10 acetyl phenothiazine with carbon disulphide, acetyl chloride and aluminium chloride to give 2,8,10 triacetyl phenothiazine, which is treated with sodium hypochlorite in dioxane, bisulphite solution, acidified and subsequently purified to give phenothiazine 2:8 dicarboxylic acid.  Phenothiazine-1-carboxylic acid is prepared by reacting lithium metal, dry ether, n-butyl bromide with phenothiazine. Excess metal is removed and the residue purified to give the acid which is converted to the potassium salt.ALSO:Polyols are stabilized by incorporating therewith an amount between 0.01 and 1 part per 100 parts of polyol of a substituted phenothiazine wherein at least one of the hydrogen atoms in positions 1-4 and 6-9 inclusive is replaced by the group COOX (wherein X is Li, Na, K, or NH+4, or the hydrogen attached to the nitrogen atom in position 10 is replaced by a polyethylene glycol group containing not less than 20 CH2CH2O units.  These compositions can be incorporated (1 pt. in 100 pts.) into an aqueous emulsion.  The polyols have 4 to 100 CH2CH2O units and polyols of ethylene and propylene oxides are specified which may be glycol, ether or ester derivatives. In preparation I, a substituted phenothiazine having a polyoxyethylene chain of 27 CH2CH2O units attached to the nitrogen atom is obtained by reacting phenothiazine and sodamide in xylene and then reacting with ethylene oxide at 150 DEG C.  After reaction xylene was removed and the residue purified.  In Table I, 60, 120, 240 mgms of the above product; 120, 240 mgms of phenothiazine 2:8 dicarboxylic acid; and 30 or 120 mgms of phenothiazine 1 carboxylic acid are respectively added per litre of a composition which comprises 5% by wt. of a polyethylene glycol (MW 600) and 95% by wt. of water.ALSO:Compositions, which on solution or dispersion in water give compositions suitable as coolants or lubricants in metal-working, comprise a polyol having incorporated therewith an amount between 0.01 and 1.0 parts per 100 parts of polyol of a substituted phenothiazine wherein at least one of the hydrogen atoms in positions 1 to 4 or 6 to 9 inclusive is replaced by the group COOX (wherein X is Li, Na, K or NH+4) or the hydrogen atom attached to the nitrogen atom in position 10 is replaced by a polyethylene glycol residue containing not less than 20 ethylene oxide units.  A polyol is olefined as being a polymer or copolymer of ethylene or propylene oxides, the copolymer being a random or block copolymer, the polyols preferably having 4 to 100 monomer units and which may be glycol, ether or ester derivatives.  Metal working compositions are obtained by adding the above compositions to water e.g. 1 part to 1 to 99 parts of water.  In examples polyol compositions containing 5% by weight of a polyethylene glycol (M.W. 600) and 95% by weight of water are stabilized by (1) an N-substituted phenothiazine compound having a polyoxy alkylene residue of 27 ethylene oxide units; (2) phenothiazine 2:8 dicarboxylic acid; and (3) phenothiazine 1 carboxylic acid.