Lubricating grease composition and preparation

Abstract

A grease composition is prepared from an isomerized base oil having consecutive numbers of carbon atoms and less than 10 wt % naphthenic carbon by n-d-M and a kinematic viscosity at 100° C. equal to or greater than 10 mm 2 /s. The grease composition in one embodiment, exhibits improved service life, i.e., capable of performing for longer period of time of at least 50% at high temperatures/speeds and in an oxidizing environment as compared to greases containing Group II or POA base oils in the prior art.

1 . A lubricating grease composition comprising (i) a lubricating base oil; (ii) from 2 to 30 wt % of a thickener selected from a simple soap, a complex soap, polyurea, diurea, triurea, fluorocarbon resin, and mixtures thereof; and (iii) 0-10 wt % of at least an additive selected from the group of preservatives, colorants, anti-weld agents, extreme pressure agents, flame retardants, rust inhibitors, corrosion inhibitors, oil bleed inhibitors, metal deactivators, viscosity modifiers, pour point depressants, and mixtures thereof;
 wherein the lubricating base oil comprises at least 50 wt. % of an isomerized base oil having consecutive numbers of carbon atoms and less than 10 wt % naphthenic carbon by n-d-M, and a kinematic viscosity at 100° C. equal to or greater than 10 mm 2 /s.   
   
   
       2 . The lubricating grease composition of  claim 1 , wherein the grease has a bearing life of at least 150 hours as determined by ASTM D3527-02. 
   
   
       3 . The lubricating grease composition of  claim 1 , wherein the grease has a maximum torque of 10 N-m at −40° C. as determined by ASTM D46930-03 at 3 minutes. 
   
   
       4 . The lubricating grease composition of  claim 1 , wherein the grease has a bearing life of at least 600 hours as determined by ASTM 3336-97. 
   
   
       5 . The lubricating grease composition of  claim 1 , wherein the grease has a dropping point of at least 215° C. as determined by ASTM D2265-06. 
   
   
       6 . The lubricating grease composition of  claim 1 , wherein the grease exhibits a peak average value of less than 12 microns/second as determined by a BeQuiet grease noise tester. 
   
   
       7 . The lubricating grease composition of  claim 1 , wherein the grease displays a difference of less than 15% difference between a prolonged worked penetration as determined by ASTM D217-02 at Full Scale, P100,000, and a worked penetration as determined by ASTM D1403-02 at ½ Scale, P60. 
   
   
       8 . The lubricating grease composition of  claim 1 , wherein the thickener is selected from the group consisting of lithium soaps, calcium soaps, sodium soaps, aluminium soaps, barium soaps, polyureas, triureas, diureas, fluorocarbon resin powder, and combinations thereof, in an amount ranging from 2 to 30 wt. % of the total weight of the grease composition. 
   
   
       9 . The lubricating grease composition of  claim 8 , wherein the thickener is a lithium complex soap. 
   
   
       10 . The lubricating grease composition of  claim 1 , wherein the at least additive is an antioxidant selected from the group of organic amines, sulfides, hydroxy sulfides, and alone or in combination with at least a metal, and mixtures thereof. 
   
   
       11 . The lubricating grease composition of  claim 10 , wherein the at least additive is an antioxidant selected from the group of alkylated diphenyl amine, phenothiazine, substituted and unsubstituted quinoline, and mixtures thereof. 
   
   
       12 . The lubricating grease composition of  claim 1 , further comprising at least a thermosetting resin. 
   
   
       13 . The lubricating grease composition of  claim 12 , in the form of a solid stick grease. 
   
   
       14 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil is a Fischer-Tropsch derived base oil made from a waxy feed. 
   
   
       15 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has an average molecular weight between 600 and 1100, and an average degree of branching in the molecules between 6.5 and 10 alkyl branches per 100 carbon atoms. 
   
   
       16 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a wt % Noack volatility between 0 and 100. 
   
   
       17 . The lubricating grease composition of  claim 16 , wherein the isomerized base oil has a Noack volatility that is less than an amount defined by: 900×(Kinematic Viscosity at 100° C.) −2.8 −15). 
   
   
       18 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has an auto-ignition temperature (AIT) greater than an amount defined by: 1.6×(Kinematic Viscosity at 40° C., in mm 2 /s)+300. 
   
   
       19 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has an auto-ignition temperature (AIT) greater than 329° C. 
   
   
       20 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a viscosity index greater than 28×Ln(Kinematic Viscosity at 100° C., in mm 2 /s)+300. 
   
   
       21 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality of greater than 15. 
   
   
       22 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a total weight percent of molecules with cycloparaffinic functionality of greater than 10, and a ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality of greater than 15. 
   
   
       23 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a viscosity index greater than an amount defined by: 28×Ln(Kinematic viscosity at 100° C.)+95. 
   
   
       24 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil is made from a process in which the highly paraffinic wax is hydroisomerized using a shape selective intermediate pore size molecular sieve comprising a noble metal hydrogenation component, and under conditions of about 600° F. to 750° F. and wherein the isomerized base oil has a Noack volatility of less than 50 weight %. 
   
   
       25 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil comprises greater than 3 weight % molecules with cycloparaffinic functionality and less than 0.30 weight percent aromatics. 
   
   
       26 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a Noack volatility less than an amount defined by: 160−40(Kinematic Viscosity at 100° C.). 
   
   
       27 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil comprises greater than 10 wt. % and less than 70 wt. % total molecules with cycloparaffinic functionality 
   
   
       28 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a traction coefficient of less than 0.023 when measured at a kinematic viscosity of 15 mm 2 /s and at a slide to roll ratio of 40%. 
   
   
       29 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a viscosity index greater than 150 and a traction coefficient less than 0.015 when measured at a kinematic viscosity of 15 mm 2 /s and at a slide to roll ratio of 40 percent. 
   
   
       30 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil comprises paraffinic hydrocarbon components having less than 8 alkyl branches per 100 carbons and less than 20 wt % of the alkyl branches are at the 2 position. 
   
   
       31 . The lubricating grease composition of  claim 1 , wherein the isomerized base oil has a pour point of less than −8° C.; a kinematic viscosity at 100° C. of at least 10 mm 2 /s; and a Viscosity Index greater than an amount defined by: 22×Ln(Kinematic Viscosity at 100° C.)+132. 
   
   
       32 . A method for making a grease composition, the method comprising blending a composition comprising a lubricating base oil with: 2 to 30 wt % of a thickener selected from a simple soap, a complex soap, polyurea, diurea, triurea, fluorocarbon resin, and mixtures thereof; and 0-10 wt % of at least an additive selected from the group of preservatives, colorants, anti-weld agents, extreme pressure agents, flame retardants, rust inhibitors, corrosion inhibitors, oil bleed inhibitors, metal deactivators, viscosity modifiers, pour point depressants, and mixtures thereof; the lubricating base oil comprises at least 50 wt. % of an isomerized base oil having a total weight percent of molecules with cycloparaffinic functionality of greater than 10, and a ratio of weight percent molecules with monocycloparaffinic functionality to weight percent molecules with multicycloparaffinic functionality of greater than 15. 
   
   
       33 . A bearing sealed with the grease composition of  claim 1 . 
   
   
       34 . An article having components lubricated by the grease composition of  claim 1 .