High throughput screening methods for lubricating oil compositions

Abstract

A method for determining oxidation stability for a plurality of different lubricating oil composition samples is provided. The methods can advantageously be optimized using combinatorial chemistry, in which a database of combinations of lubricating oil compositions is generated. As market conditions vary and/or product requirements or customer specifications change, conditions suitable for forming desired products can be identified with little or no downtime.

1 . A high throughput method for screening lubricating oil compositions, under program control, comprising: 
 (a) providing a plurality of different lubricating oil composition samples comprising (i) a major amount of at least one base oil of lubricating viscosity and (ii) a minor amount of at least one lubricating oil additive, each sample being in a respective one of a plurality of test receptacles;    (b) measuring the oxidation stability of each sample to provide oxidation stability data for each sample; and,    (c) outputting the results of step (b).    
     
     
         2 . The method of  claim 1 , wherein the base oil is a natural or synthetic oil.  
     
     
         3 . The method of  claim 1 , wherein the lubricating oil additive is selected from the group consisting of antioxidants, anti-wear agents, detergents, rust inhibitors, dehazing agents, demulsifying agents, metal deactivating agents, friction modifiers, pour point depressants, antifoaming agents, co-solvents, package compatibilisers, corrosion-inhibitors, ashless dispersants, dyes, extreme pressure agents and mixtures thereof.  
     
     
         4 . The method of  claim 1 , wherein the step of measuring the oxidation stability of each sample comprises exposing the sample to oxygen at a predetermined temperature for a predetermined time period and determining the amount of oxygen consumed by the sample.  
     
     
         5 . The method of  claim 1 , wherein the step of measuring the oxidation stability of each sample comprises exposing the sample to a predetermined amount of oxygen at a predetermined temperature for a predetermined time period and determining the amount of time required for the sample to consume the predetermined quantity of oxygen.  
     
     
         6 . The method of  claim 1 , wherein the step of measuring the oxidation stability of each sample comprises subjecting the sample to oxidation reaction conditions in the presence of a substrate and determining the amount of deposit formed on the substrate after a predetermined period of reaction time.  
     
     
         7 . The method of  claim 1 , wherein the step of measuring the oxidation stability of each sample comprises using infrared spectroscopy.  
     
     
         8 . The method of  claim 7 , wherein the infrared spectroscopy is Fourier-transform infrared spectroscopy (FTIR).  
     
     
         9 . The method of  claim 1 , wherein the step of measuring the oxidation stability of each sample is determined by differential scanning calorimetry.  
     
     
         10 . The method of  claim 1 , wherein in step (c) the results of step (b) for each sample are transmitted to a computer, wherein the computer compares the results with a predetermined value delimiting a failure or passing of the results, and the computer identifies failed samples to preclude further testing of the failed samples.  
     
     
         11 . The method of  claim 1 , wherein the step of outputting comprises storing the results of step (b) on a data carrier.  
     
     
         12 . The method of  claim 1 , further comprising the step of using the results of step (b) as a basis for obtaining a result of further calculations.  
     
     
         13 . The method of  claim 11 , further comprising the step of transmitting the results of step (b) to a data carrier at a remote location.  
     
     
         14 . The method of  claim 12 , further comprising the step of transmitting the results of further calculations to a remote location.  
     
     
         15 . A system for screening lubricating oil composition samples, under program control, comprising: 
 a) a plurality of test receptacles, each containing a different lubricating oil composition sample comprising (i) a major amount of at least one base oil of lubricating viscosity and (ii) a minor amount of at least one lubricating oil additive;    b) a computer controller for selecting individual samples for testing;    c) receptacle moving means responsive to instructions from the computer controller for individually moving the selected samples to a testing station for measuring oxidation stability of the selected samples;    d) means for measuring the oxidation stability of the selected samples to obtain oxidation stability data and for transferring the oxidation stability data to the computer controller.    
     
     
         16 . The system of  claim 15 , wherein the receptacle moving means comprises a movable carriage.  
     
     
         17 . The system of  claim 15 , wherein the receptacle moving means comprises a robotic assembly having a movable arm for grasping and moving a selected individual receptacle.  
     
     
         18 . The system of  claim 15 , wherein the receptacle moving means comprises means for agitating the test receptacles.  
     
     
         19 . The system of  claim 15  wherein the means for measuring oxidation stability comprises means for measuring the consumption of oxygen of the selected samples.  
     
     
         20 . The system of  claim 15  wherein the means for measuring oxygen stability comprises means for measuring deposit formation on a transparent glass substrate resulting from oxidation of the selected samples.  
     
     
         21 . The system of  claim 18  wherein the means for measuring deposit formation includes a light source and a photocell aligned with the light source.  
     
     
         22 . The system of  claim 15  wherein each test receptacle has a bar code affixed to an outer surface thereof.  
     
     
         23 . The system of  claim 22  further comprising a bar code reader.