Stable dispersions of oil-insoluble compounds In hydrocarbons for use in lubricants

Abstract

An additive package including an oil-insoluble additive, a method for forming an additive package with an oil-insoluble additive and a lubricant in the form of a dispersion of an oil-insoluble additive in oil is described where an oil-insoluble solvent, e.g. water, can be used to help create the dispersed phase. These packages, methods and lubricants are beneficial in various applications such as internal combustion engines where the oil benefits from functional additives that are not readily soluble in the oil. In many embodiments the oil-insoluble solvent is partially or fully removed before use.

1 . An additive package for a lubricant or functional fluid comprising 
 a) an oil of lubricating viscosity,    b) at least one emulsifier capable of forming a water in oil emulsion,    c) optionally an oil insoluble solvent(s) and    d) at least 0.1 part by weight of an oil insoluble functional lubricant additive selected from friction modifiers including extreme pressure additive, corrosion inhibitor, antioxidant, or metal protectorant characterized as being an oil insoluble dispersed phase partially or completely stabilized as a dispersion by said at least one emulsifier, wherein said oil insoluble functional additive is neither characterized as a detergent (e.g. overbased metals) nor a borate compound, wherein said parts by weight are based upon 100 parts by weight of said additive package, and wherein the amount of said oil-insoluble solvent is less than 20% by weight based on the weight of said package.    
     
     
         2 . An additive package according to  claim 1 , wherein the oil less said functional additive, emulsifier, and optional solvent has a viscosity from about 2 centistokes to about 50 centistokes at 50° C. and said functional additive is in a dispersed phase having less than 30 wt. % of said oil insoluble solvent(s) based on the weight of said additive and wherein said dispersed phase has an intensity average particle size by light scattering of 1 or 5 nanometers to 100 microns.  
     
     
         3 . An additive package according to  claim 1 , wherein said oil insoluble solvent(s) is from about 0 to about 20 weight percent of the weight of said functional additive.  
     
     
         4 . An additive package according to  claim 3  said functional additive is in a dispersed phase having an intensity average particle size by light scattering of from 1 or 5 nanometers to 100 microns.  
     
     
         5 . An additive package according to  claim 1 , further comprising at least one conventional lubricating oil additive selected from dispersant(s), detergent(s), viscosity modifier(s), and antioxidant(s) in a total amount of at least 1 part by weight per 100 parts by weight of said additive package.  
     
     
         6 . An additive package according to  claim 5 , wherein said at least one emulsifier comprises a polyisobutylene functionalized succan portion having a number average molecular weight of at least 600 reacted with one or more other chemicals to provide a polar end group or (please give me a list of other emulsifiers e.g. a salixarene, or a Mannich dispersant).  
     
     
         7 . An additive package according to  claim 5 , further comprising at least one antioxidant selected from a metal dithiophosphate, a hindered phenol, an aromatic amine, sulfurized olefin, copper antioxidant, salicylate acid or its derivative or a sulfurized phenol.  
     
     
         8 . An additive package according to  claim 5 , wherein said oil insoluble functional additive is present as a dispersed phase with an intensity average particle diameter by light scattering from about 20 nanometers to about 10 microns and wherein said oil-insoluble solvent is present in an amount of less than 20 weight percent based on the weight of said oil-insoluble functional additive.  
     
     
         9 . An additive package according to  claim 8 , wherein said oil insoluble functional additive is an antioxidant or an antiwear additive.  
     
     
         10 . A lubricant comprising; 
 a) from about 50 to about 99 wt. % of one or more oils of lubricating viscosity,    b) less than 20 wt. % total of oil insoluble solvent(s)    c) from about 0.02 to about 15 wt. % of a emulsifier(s) capable of forming a water in oil emulsion    from about 0.01 to about 40 wt. % of an oil insoluble functional additive selected from extreme pressure additive, corrosion inhibitor, antioxidant, metal protectorant, wherein said oil insoluble functional additive is present as a dispersed phase optionally with said oil insoluble solvent(s) present, wherein said oil insoluble functional additive is neither characterized as a detergent (e.g. overbased metals) nor a borate, and wherein said wt. % is based on the weight of said lubricant.    
     
     
         11 . A lubricant according to  claim 10 , wherein said oil insoluble functional additive is present as a dispersed phase with an intensity average particle diameter by light scattering from about 20 nanometers to about 10 microns and wherein said oil-insoluble solvent is present in an amount of less than 20 weight percent based on the weight of said oil-insoluble functional additive.  
     
     
         12 . A lubricant according to  claim 11 , further comprising at least one conventional lubricating oil additive selected from dispersant(s), detergent(s), viscosity modifier(s), and antioxidant(s) in a total amount of at least 1 part by weight per 100 parts by weight of said additive package.  
     
     
         13 . A lubricant according to  claim 12 , wherein said at least one emulsifier comprises a polyisobutylene functionalized succan portion having a number average molecular weight of at least 600 reacted with one or more other chemicals to provide a polar end group or (please give me a list of other emulsifiers e.g. a salixarene, or a Mannich dispersant).  
     
     
         14 . A lubricant according to  claim 11 , further comprising at least on antioxidant selected from a metal dithiophosphate, a hindered phenol, an aromatic amine, sulfurized olefin, copper antioxidant, salicylate acid or its derivative or a sulfurized phenol.  
     
     
         15 . A process for forming an additive package for a functional fluid (including a lubricant) comprising; 
 a) dissolving or dispersing an oil insoluble functional additive in an oil insoluble solvent e.g. water forming a dispersion or blend,    b) adding said dispersion or blend of said oil insoluble functional additive and oil insoluble solvent to a lubricating oil,    c) dispersing said dispersion or blend of said oil insoluble functional additive and solvent in said lubricating oil as a dispersed phase using a water in oil type emulsifier, and    d) thereafter removing a portion or all of said solvent(s) so that the total oil insoluble solvent content in the dispersed phase is less than 30 wt. % based on the weight of said functional additive(s)    e) wherein said insoluble functional additive is neither a borate compound nor an overbased or neutral metal detergent.    
     
     
         16 . A process according to  claim 15  wherein after step d, the amount of oil insoluble solvent is present at less than 20 wt. %, and preferably less than 10 or 5 wt. % based on the weight of said functional additive.  
     
     
         17 . A process according to  claim 15  further comprising a step of adding at least one part by weight of a conventional oil soluble additive selected from antioxidant, dispersant, detergent, viscosity modifier, antiwear additive or combinations thereof based on 100 parts by weight of said additive package or lubricant.  
     
     
         18 . A process according to  claim 15 , wherein said oil insoluble functional additive is present after said steps as a dispersed phase with an intensity average particle diameter by light scattering from about 20 nanometers to about 10 microns and wherein said oil-insoluble solvent is present in an amount of less than 20 weight percent based on the weight of said oil-insoluble functional additive.  
     
     
         19 . A process according to  claim 15 , wherein said oil-in-water emulsifier comprises a polyisobutylene functionalized succan portion having a number average molecular weight of at least 600 reacted with one or more other chemicals to provide a polar end group or (please give me a list of other emulsifiers e.g. a salixarene, or a Mannich dispersant).  
     
     
         20 . A process for preparing an oil insoluble component for additive package for a functional fluid or a lubricant comprising; 
 a) dissolving or dispersing an oil insoluble functional additive in an oil insoluble solvent(s) (e.g. water) forming a mixture,    b) adding said mixture to a lubricating oil,    c) dispersing said mixture in said lubricating oil as a dispersed phase using a water in oil type emulsifier, and    d) thereafter removing at least 50 weight percent of the original portion of said oil insoluble solvent(s), so that the total oil insoluble solvent content in the dispersed phase is less than 30 wt. % based on the weight of said functional additive and wherein said oil insoluble functional additive is neither a conventional lubricant detergent nor a borate compound.    
     
     
         21 . A process according to  claim 20 , wherein said oil insoluble functional additive is metal containing antioxidant (e.g. copper).  
     
     
         22 . A process according to  claim 20 , wherein said oil insoluble functional additive is an antiwear or extreme pressure additive.  
     
     
         23 . A process according to  claim 20 , wherein said oil insoluble functional additive is a compound(s) containing bismuth, inorganic phosphates (as opposed to organic phosphates), or molybdenum.