Additives containing polytetrafluoroethylene for making stable lubricants
OwnerFrederic C. McCoyinventor
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Abstract
A lubricating oil additive comprising a stable dispersion of finely divided polytetrafluoroethylene particles having a relatively high molecular weight, a polymeric, oil-soluble dispersant containing nitrogen, an organo-clay anti-sedimentation agent and a polar activator therefor in a lubricating oil, the additives being free of polytetrafluoroethylene sedimentation, together with lubricating oils containing such additives and processes for producing the additives.
Claims23
A concentrated non-aqueous lubricant additive having excellent resistance to sedimentation, said additive comprising in parts by weight, a mixture of:
- (a) about 0.5% to about 10% particulate polytetrafluoroethylene having a particle size in the range from about 0.1 microns to about 4 microns;
- (b) about 3% to about 15% of a nitrogen-containing polymeric dispersing agent effective to disperse the polytetrafluoroethylene;
- (c) about 0.5% to about 2% of an organo-clay anti-sedimentation agent effective to prevent polytetrafluoroethylene sedimentation;
- (d) about 1% to about 2.5% of an oil-miscible polar additive to deagglomerate said organo-clay;
- and
- (e) a lubricating carrier oil.
A method of preparing a non-aqueous lubricant additive having excellent resistance to sedimentation, comprising the steps of:
- (a) preparing a mixture of carrier oil, about 3% to about 15% by weight of said additive of a nitrogen-containing polymeric dispersing agent and about 1% to about 2.5% by weight of said additive of an oil-miscible polar additive;
- (b) adding to the mixture about 0.5% to about 2% by weight of the first-mentioned said additive of an organo-clay anti-sedimentation agent and about 0.5% to about 10% by weight of the first mentioned said additive of a non-aqueous particulate polytetrafluoroethylene having a particle size in the range from about 0.1 microns to about 4 microns to form a dispersion;
- (c) subjecting the dispersion to high shear forces.
A concentrated non-aqueous lubricant additive having excellent resistance to sedimentation, said additive comprising, in parts by weight, a mixture of:
- (a) about 0.5% to about 10% of particulate polytetrafluoroethylene having a particle size in the range from about 0.1 micron to about 4 microns;
- (b) about 3% to about 15% of a nitrogen-containing polymeric dispersing agent effective to disperse the polytetrafluoroethylene and selected from methacrylate ester-dialkylaminoalkyl methacrylate copolymer, methacrylate ester-dimenthylaminoethyl methacrylate copolymer, ethylene-propylene copolymer and mixtures thereof;
- (c) about 0.5% to about 2% of a tetraalkyl ammonium clay antisedimentation agent effective to prevent polytetrafluoroethylene sedimentation;
- (d) about 1% to about 2.5% ofan oil-miscible polar additive to deglomerate said clay and which is an ethoxylated alkylphenol having about four ethoxy groups per molecule;
- and
- (e) the balance essentially a lubricating carrier oil.
Dependencies are inferred from the claim text.