Patent GB-721468-A (GB)
Title: Polysiloxane-aluminum soap greases
IPC: C08K5/098
Filed: 1952-01-25
Abstract: A polysiloxane grease composition comprises a major proportion of a polysiloxane base oil and a complex basic aluminium soap containing both relatively oleophilic anions and relatively oleophobic anions. The polysiloxane oil may have the formula <FORM:0721468/IV (a)/1> where R is an alkyl or a alkenyl radical containing no more than 5 carbon atoms and may be derived from methane, ethane, propane, propene, butane, butene, pentane or pentene; R1 is an alkaryl or aralkyl radical (the alkyl group attached to the aromatic nucleus containing no more than 3 carbon atoms), and may be derived from benzene, anthracene, phenyl methane, phenyl ethane, phenyl propane, methyl benzene, ethyl benzene or propyl benzene, and n is at least 10.  The preferred polysiloxane oil has the above formula where R is methyl and R1 is phenyl.  The complex basic aluminium soap contains at least one hydroxyl anion for each aluminium cation and at least two dissimilar organic anions, and is polymeric in structure, for example, aluminium benzoate stearate, aluminium benzoate oleate, aluminium benzoate 12-hydroxy stearate, aluminium toluate stearate, aluminium benzoate naphthenate, aluminium benzoate hydrogenated rosin, aluminium benzoate cetyl benzene sulphonate, aluminium azelate stearate and aluminium phosphate benzoate stearate.  The composition may contain 15 to 40 per cent. preferably 25 to 35 per cent, of aluminium soap.ALSO:A grease composition comprises a major proportion of a polysiloxane base oil and, in an amount sufficient to thicken the polysiloxane base oil to the consistency of a grease, a complex basic aluminium soap containing both relatively oleophilic anions and relatively oleophobic anions.  The polysiloxane base oil may have the formula <FORM:0721468/III/1> where R is an alkyl radical containing no more than five carbon atoms, and may be derived from methane, ethane, propane, propene, butane, butene, pentane or pentene; R1 is an alkaryl radical or aralkyl radical (the alkyl group attached to the aromatic nucleus containing no more than three carbon atoms) and may be derived from benzene, anthracene, phenyl methane, phenyl ethane, phenyl propane, methyl benzene, ethyl benzene or propyl benzene; and n is the number of monomeric units present in the polymer, and is at least 10.  The preferred polysiloxane oil has the above formula where R is methyl and R1 is phenyl.  The complex basic aluminium soap contains at least one hydroxyl anion for each aluminium cation and at least two dissimilar organic anions, and is polymeric in structure.  The relatively oleophilic anions may be derived from caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydroxy stearic acid, arachidic acid, melissic acid, oleic acid, linoleic acid, butyl benzoic acid, hexyl benzoic acid, octyl benzoic acid, dodecyl benzoic acid, phenyl butyric acid, phenyl hexanoic acid, phenyl decanoic acid, cetyl benzene sulphonic acid, a di-dodecyl benzene sulphonic acid, an alkane phosphonic acid having at least 24 carbon atoms in the alkane group, cetyl thiophosphoric acid or naphthenic acids.  The relatively oleophobic anions may be derived from benzoic acid, methyl benzoic acid, ethyl benzoic acid, toluic acid, phenylacetic acid, phenyl propionic acid, oxalic acid, malonic acid, isosuccinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, phthalic acid, salicylic acid, carboxy methyl cellulose or polyacrylic acid.  Examples of complex basic aluminium soaps are aluminium benzoate stearate, aluminium benzoate oleate, aluminium benzoate 12-hydroxy stearate, aluminium toluate stearate, aluminium benzoate naphthenate, aluminium benzoate hydrogenated rosin, aluminium benzoate cetylbenzene sulphonate, aluminium azelate stearate and aluminium phosphate benzoate stearate.  The composition may contain 15 to 40 per cent., preferably 25 to 35 per cent., of aluminium soap.