Patent GB-796603-A (GB)
Title: Improvements in and relating to inhibitors of oxidation, peroxidation and polymerisation
Inventor: KNOWLTON ROBERT ELLIS
IPC: C07D307/12
Filed: 1955-05-18
Abstract: Organic substances, liable to deterioration as the result of peroxide formation, are stabilized by the addition thereto of a small proportion (at most 1 per cent by weight) of a plurality of mononuclear monohydric phenols chosen so that (A) at least one of these phenols has 2 tertiary alkyl nuclear substituents ortho to the hydroxy position and (B) at least one other of these phenols has only one tertiary alkyl nuclear substituent ortho to the hydroxy position or has no tertiary alkyl nuclear substituent ortho to the hydroxy position.  The phenols of each type may carry other nuclear substituents but these must be alkyl groups other than tertiary alkyl groups.  Organic substances mentioned as being liable to deterioration as the result of peroxide formation are petrol, petroleum oil compositions such as lubricating oils, transformer oils and turbine oils, mineral and vegetable oils, greases, waxes, natural and synthetic rubbers, fats, foodstuffs, aldehydes and tetrahydrofurfuryl alcohol.  Phenols of type A include 2,6-di-tert.-butyl-phenol, 2,4,6-tri-tert.-butyl - phenol, 4 - methyl - 2,6 - di - tert. - butyl-phenol, 4 - ethyl - 2,6 - di - tert. - butyl - phenol, 4 - methyl - 2,6 - di - (2 - methylpentyl - 2) - phenol and 4 - methyl - 2 - (2,4,4 - trimethyl-pentyl - 2) - 6 - tert. - butyl - phenol.  Type B phenols mentioned are phenol, xylenols, cresols, 2,3,5 - trimethyl - phenol, 2,4,6 - trimethyl-phenol, 2,4,5 - trimethyl - phenol, 2 - methyl - 6 - tert. - butyl - phenol, 3 - methyl - 6 - tert. - phenol, 4 - methyl - 2 - tert. - butyl - phenol, 2,4 - di - tert. - butyl - phenol, 3,4 - dimethyl - 6 - tert. - butyl - phenol, 2,6 - dimethyl - 4 - tert. - butyl - phenol, 2,5 - dimethyl - 4 - tert. - butyl - phenol, 2 - methyl - 4,6 - di - tert. - butyl - phenol and 3 - methyl - 4,6 - di - tert. - butyl-phenol. In examples, the stabilizing effects of various phenols and mixtures of phenols on petrol or nonaldehyde (3,5,5-tri-methyl-hexaldehyde) are described.ALSO:Organic substances, liable to deterioration as the result of peroxide formation, are stabilized by the addition thereto of a small proportion (at most 1 per cent by weight) of a plurality of mononuclear monohydric phenols chosen so that (A) at least one of these phenols has 2 tertiary alkyl nuclear substituents ortho to the hydroxy position and (B) at least one other of these phenols has only one tertiary alkyl nuclear substituent ortho to the hydroxy position or has no tertiary alkyl nuclear substituent ortho to the hydroxy position.  The phenols of each type may carry other nuclear substituents but these must be alkyl groups other than tertiary alkyl groups.  Organic substances mentioned as being liable to deterioration as the result of peroxide formation include petrol, petroleum oil compositions such as lubricating oils, transformer oils and turbine oils, mineral and vegetable oils, greases and fats.  Phenols of type A include 2,6 - di - tert. - butyl - phenol, 2,4,6 - tri - tert.-butyl - phenol, 4 - methyl - 2,6 - di - tert. - butyl-phenol, 4 - ethyl - 2,6 - di - tert. - butyl - phenol, 4-methyl-2,6-di-(2-methylpentyl-2)-phenol and 4 - methyl - 2 - (2,4,4 - trimethylpentyl - 2) - 6 - tert.-butyl-phenol.  Type B phenols mentioned are phenol, xylenols, cresols, 2,3,5-trimethyl-phenol, 2,4,6-trimethyl-phenol, 2,4,5-trimethyl-phenol, 2 - methyl - 6 - tert. - butyl - phenol, 3 - methyl - 6 - tert. - butyl - phenol, 4 - methyl - 2 - tert. - butyl - phenol, 2,4 - di - tert. - butyl - phenol, 3,4 - dimethyl - 6 - tert. - butyl - phenol, 2,6 - dimethyl - 4 - tert. - butyl - phenol, 2,5-dimethyl - 4 - tert. - butyl - phenol, 2 - methyl - 4,6 - di - tert. - butyl - phenol and 3 - methyl - 4,6 - di - tert. - butyl phenol.  In examples, the stabilizing effects of various phenols and mixtures of phenols on petrol are described.ALSO:Organic substances, liable to deterioration as the result of peroxide formation, are stabilized by the addition thereto of a small proportion (at most 1 per cent by weight) of a plurality of mononuclear monohydric phenols chosen so that (A) at least one of these phenols has 2 tertiary alkyl nuclear substituents ortho to the hydroxy position and (B) at least one other of these phenols has only one tertiary alkyl nuclear substituent ortho to the hydroxy position or has no tertiary alkyl nuclear substituent ortho to the hydroxy position.  The phenols of each type may carry other nuclear substituents but these must be alkyl groups other than tertiary alkyl groups.  Organic substances mentioned as being liable to deterioration as the result of peroxide formation include rubber.  Phenols of type A include 2,6 - di - tert.butyl - phenol, 2,4,6 - tri - tert.butyl - phenol, 4 - methyl - 2,6 - di - tert. butyl - phenol, 4 - ethyl - 2,6 - di - tert.butyl - phenol, 4 - methyl - 2,6 - di - (2 - methylpentyl - 2) - phenol and 4 - methyl - 2 - (2,4,4 - tri - methylpentyl - 2) - 6 - tert.butyl - phenol.  Type B phenols mentioned are phenol, xylenols, cresols, 2,3,5 - trimethyl - phenol, 2,4,6 - trimethyl - phenol, 2,4,5 - trimethyl - phenol, 2 - methyl - 6 - tert.butyl - phenol, 3 - methyl - 6 - tert.butyl - phenol, 4 - methyl - 2 - tert.butyl - phenol, 2,4 - di-tert.butyl - phenol, 3,4 - dimethyl - 6 - tert.butyl - phenol, 2,6 - dimethyl - 4 - tert.,butyl - phenol, 2,5 - dimethyl - 4 - tert. butyl - phenol, 2 - methyl - 4,6 - di - tert.butyl - phenol and 3 - methyl - 4,6 - di - tert.butyl phenol.ALSO:Foods, especially vegetable oils and fats, liable to deterioration as the result of peroxide formation, are stabilized by the addition thereto of a small proportion (at most 1 per cent by weight) of a plurality of mononuclear monohydric phenols chosen so that (a) at least one of these phenols has 2 tertiary alkyl nuclear substituents ortho to the hydroxy position; and (b) at least one other of these phenols has only one tertiary alkyl nuclear substituent ortho to the hydroxy position or has no tertiary alkyl nuclear substituent ortho to the hydroxy position. The phenols of each type may carry other nuclear substituents but these must be alkyl groups other than tertiary alkyl groups.