Alkoxylated alcohols for increasing the breakdown voltage of a lubricant

Abstract

The present invention relates a lubricant comprising a base stock selected from hydrocarbons, 50 to 1000 ppm water, and an alkoxylated alcohol, where the alcohol is alkoxylated with a hydrophobic epoxide selected from C 4 -C 20 epoxides. The invention also relates to a method for lubricating a mechanical device in an electric vehicle comprising the step of contacting the lubricant with the mechanical device; to a use of the alkoxylated alcohol for increasing the breakdown voltage of a lubricant comprising the basestock selected from the hydrocarbons; and to a use of the alkoxylated alcohol in a lubricant comprising the base stock selected from the hydrocarbons for reducing the electric discharge machining.

1 .- 15 . (canceled) 
     
     
         16 . A method for lubricating a mechanical device in an electric vehicle comprising the step of contacting the lubricant with the mechanical device, where the lubricant comprises
 a base stock selected from hydrocarbons,   50 to 1000 ppm water, and   an alkoxylated alcohol, where the alcohol is alkoxylated with a hydrophobic epoxide selected from C 4 -C 20  epoxides.   
     
     
         17 . The method according to  claim 16  where the hydrophobic epoxide is selected from butylene oxide, dodecyl oxide, or a mixture thereof. 
     
     
         18 . The method according to  claim 16  where the alcohol is alkoxylated with the hydrophobic epoxide and optionally in addition with propylene oxide. 
     
     
         19 . The method according to  claim 16  where the alcohol is a selected from C 1 -C 22  monoalcohol, C 2 -C 12  diol, polyethylene glycol, polypropylene glycol, polytetrahydrofurane, or C 3 -C 12  polyol. 
     
     
         20 . The method according to  claim 16  where the lubricant comprises 2 to 50 wt % of the alkoxylated alcohol. 
     
     
         21 . The method according to  claim 16  where the hydrocarbons are selected from API Groups I, II, III or IV base stocks, or mixtures thereof. 
     
     
         22 . The method according to  claim 16  where the lubricant is free from API Group V base stocks. 
     
     
         23 . The method according to  claim 16  where the base stock has a breakdown voltage of up to 500 Volt. 
     
     
         24 . The method according to  claim 16  where the alkoxylated alcohol is an alkoxylated polytetrahydrofurane of general formula (I) 
       
         
           
           
               
               
           
         
         wherein 
         m is an integer in the range of ≥1 to ≤50, 
         m′ is an integer in the range of ≥1 to ≤50, 
         (m+m′) is an integer in the range of ≥1 to ≤90, 
         n is an integer in the range of ≥0 to ≤75, 
         n′ is an integer in the range of ≥0 to ≤75, 
         p is an integer in the range of ≥0 to ≤75, 
         p′ is an integer in the range of ≥0 to ≤75, 
         k is an integer in the range of ≥2 to ≤30, 
         R 1  denotes an unsubstituted, linear or branched, alkyl radical having 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27 or 28 carbon atoms, 
         R 2  denotes —CH 2 —CH 3 , and 
         R 3  identical or different, denotes a hydrogen atom or —CH 3 , 
         whereby the concatenations denoted by k are distributed to form a block polymeric structure and the concatenations denoted by p, p′, n, n′, m and m′ are distributed to form a block polymeric structure or a random polymeric structure. 
       
     
     
         25 . The method according to  claim 16  where the lubricant comprises at least 50 wt % of the base stock. 
     
     
         26 . A lubricant as defined in  claim 16  comprising
 a base stock selected from hydrocarbons which are selected from API Groups I, II, or III base stocks, 
 50 to 1000 ppm water, and 
 an alkoxylated alcohol, where the alcohol is alkoxylated with a hydrophobic epoxide selected from C 4 -C 20  epoxides, and where the alcohol is a diol selected from C 2 -C 12  diol, polyethylene glycol, polypropylene glycol and polytetrahydrofurane. 
 
     
     
         27 . A use of the alkoxylated alcohol as defined in  claim 16  for increasing the breakdown voltage of a lubricant comprising the basestock selected from the hydrocarbons. 
     
     
         28 . The use according to  claim 27  where the breakdown voltage of the lubricant comprising the alkoxylated alcohol is at least 100 V higher compared to the lubricant without the alkoxylated alcohol. 
     
     
         29 . A use of the alkoxylated alcohol as defined in  claim 16  in a lubricant comprising the base stock selected from the hydrocarbons for reducing the electric discharge machining.