Composition Containing a Block Copolymer and a Method of Lubricating an Internal Combustion Engine

Abstract

The invention provides a lubricating composition containing an oil of lubricating viscosity and a block copolymer. The block copolymer may contain (a) a hydrophobic first block having C1-30 alkyl (meth)acrylic units, wherein at least 50 wt % of the C1-30 alkyl (meth)acrylic units are C12-15 alkyl (meth)acrylic units, and up to 50 wt % of the C1-30 alkyl (meth)acrylic units are C16 20 alkyl (meth)acrylic units, with the proviso that alkyl groups of the C1-30 alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and (b) a second block having (meth)acrylic units further having a heteroatom-containing group providing a polar group. The invention further relates to a method of lubricating an internal combustion engine by lubricating the engine with the lubricating composition. The invention further relates to the use of the block copolymer as an emulsifier and/or pour point depressant.

1 - 16 . (canceled) 
     
     
         17 . A method of lubricating an internal combustion engine comprising supplying to the engine a lubricating composition comprising an oil of lubricating viscosity and a block copolymer, wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         18 . The method of  claim 17 , wherein the internal combustion engine is a flexible fuel vehicle engine. 
     
     
         19 . The method of  claim 17 , wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 50 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 50 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units further having a heteroatom group providing a polar group.   
     
     
         20 . The method of  claim 17 , wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 70 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 30 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         21 . The method of  claim 17 , wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 80 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 20 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         22 . The method of  claim 17 , wherein the heteroatom-containing group of the second block contains sulphur, nitrogen, non-carbonyl oxygen, phosphorus, or mixtures thereof. 
     
     
         23 . The method of  claim 17 , wherein the heteroatom-containing group of the second block contains nitrogen. 
     
     
         24 . The method of  claim 17 , wherein the heteroatom-containing group is derived from a nitrogen containing monomer selected from the group consisting of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, dimethylaminopropyl acrylate, dimethylaminopropylacrylamide, dimethylaminopropylmethacrylamide, and mixtures thereof. 
     
     
         25 . The method of  claim 17 , wherein the block copolymer is a methacrylate polymer. 
     
     
         26 . The method of  claim 17 , wherein the block copolymer is a linear diblock copolymer. 
     
     
         27 . The method of  claim 17 , wherein the block copolymer is obtained from a controlled radical polymerisation process or other living polymerisation process. 
     
     
         28 . The method of  claim 27 , wherein the controlled radical or other living polymerisation process is one of RAFT (Reversible Addition Fragmentation Transfer), ATRP (Atom Transfer Radical Polymerisation), nitroxide-mediated or anionic polymerisation. 
     
     
         29 . The method of  claim 28 , wherein the controlled radical polymerisation process is a RAFT process. 
     
     
         30 . A lubricating composition comprising an oil of lubricating viscosity and a block copolymer comprising:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 50 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 50 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         31 . The lubricating composition of  claim 30 , wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 70 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 30 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         32 . The lubricating composition of  claim 30 , wherein the block copolymer comprises:
 (a) a hydrophobic first block having C 1-30  alkyl (meth)acrylic units, wherein at least 80 wt % of the C 1-30  alkyl (meth)acrylic units are C 12-15  alkyl (meth)acrylic units, and up to 20 wt % of the C 1-30  alkyl (meth)acrylic units are C 16-20  alkyl (meth)acrylic units, with the proviso that alkyl groups of the C 1-30  alkyl (meth)acrylic units have an average total number of carbon atoms of at least 8; and   (b) a second block having (meth)acrylic units which further have a non-carbonyl heteroatom-containing group providing a polar group to such units, whereby said second block exhibits greater hydrophilicity than does the hydrophobic first block.   
     
     
         33 . The lubricating composition of  claim 30 , wherein the heteroatom-containing group of the second block contains sulphur, nitrogen, non-carbonyl oxygen, phosphorus, or mixtures thereof. 
     
     
         34 . The lubricating composition of  claim 30 , wherein the heteroatom-containing group of the second block contains nitrogen. 
     
     
         35 . The lubricating composition of  claim 30 , wherein the heteroatom-containing group is derived from a nitrogen containing monomer selected from the group consisting of dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, dimethylaminopropyl acrylate, dimethylamino-propylacrylamide, dimethylaminopropylmethacrylamide, and mixtures thereof. 
     
     
         36 . The lubricating composition of  claim 30 , wherein the block copolymer is a methacrylate polymer. 
     
     
         37 . The lubricating composition of  claim 30 , wherein the block copolymer is a linear diblock copolymer. 
     
     
         38 . The lubricating composition of  claim 30 , wherein the block copolymer is obtained from a controlled radical polymerisation process or other living polymerisation process. 
     
     
         39 . The lubricating composition of  claim 38 , wherein the controlled radical or other living polymerisation process is one of RAFT (Reversible Addition Fragmentation Transfer), ATRP (Atom Transfer Radical Polymerisation), nitroxide-mediated or anionic. 
     
     
         40 . The lubricating composition of  claim 38 , wherein the controlled radical polymerisation process is a RAFT process.