Lubricant polymers

Abstract

Lubricant compositions include copolymers of monomers selected from C6-C10 alkyl methacrylate monomers, and monomers selected from C10-C18 alkyl methacrylate monomers, and a base oil or comprising a copolymer obtained by combining at least monomers selected from C6-C10 alkyl methacrylate monomers, and monomers selected from C10-C18 alkyl methacrylate monomers in a mixture and co-polymerizing the monomers. The lubricant compositions may find use in lubricating two-stroke marine engines by applying the lubricant compositions to at least one component of a two-stroke marine engine.

What is claimed: 
     
         1 . A lubricant composition comprising:
 from 0.01% to 10% by weight, relative to the total weight of the lubricant composition, of a copolymer of alkyl methacrylate monomers, wherein said alkyl methacrylate monomers consist essentially of:
 a. Monomers (A) selected from C6-C10 alkyl methacrylate monomers, and 
 b. Monomers (B) selected from C10-C18 alkyl methacrylate monomers, the Monomers (B) consisting of a C12 alkyl methacrylate monomer or the Monomers (B) comprising a mixture of about 0.1 to 2% by weight of C10 alkyl methacrylate, about 50 to 80% by weight of C12 alkyl methacrylate, about 15 to 40% by weight of C14 alkyl methacrylate, about 2 to 12% by weight of C16 alkyl methacrylate and about 0.1 to 1% by weight of C18 alkyl methacrylate based on a total weight of the mixture, 
 and the mass ratio of Monomer (B) to Monomer (A) in the copolymer is 99:1 to 10:90, 
   a base oil.   
     
     
         2 . The lubricant composition according to  claim 1  wherein the copolymer is obtained by combining at least
 a. Monomers (A) selected from C6-C10 alkyl methacrylate monomers, and 
 b. Monomers (B) selected from C10-C18 alkyl methacrylate monomers, said monomers (B) comprising at least one C12 alkyl methacrylate monomer, 
 in a mixture and co-polymerizing the monomers. 
 
     
     
         3 . The lubricant composition of  claim 1 , wherein the monomers (B) further comprise at least one C14 alkyl methacrylate monomer. 
     
     
         4 . The lubricant composition according to  claim 1 , wherein monomers (A) are branched. 
     
     
         5 . The lubricant composition according to  claim 4 , wherein monomers A are 2-ethyl hexyl methacrylate. 
     
     
         6 . The lubricant composition according to  claim 1 , wherein monomers (B) are linear. 
     
     
         7 . The lubricant composition according to  claim 6 , wherein monomers (B) are a mixture of C10 alkyl methacrylate, C12 alkyl methacrylate, C14 alkyl methacrylate, C16 alkyl methacrylate and C18 alkyl methacrylate. 
     
     
         8 . The lubricant composition according to  claim 1 , wherein the copolymer is a copolymer of a mixture of C10 alkyl methacrylate, C12 alkyl methacrylate, C14 alkyl methacrylate, C16 alkyl methacrylate and C18 alkyl methacrylate, and a C8 alkyl methacrylate. 
     
     
         9 . The lubricant composition according to  claim 1 , wherein the mass ratio of the monomers (B) to monomers (A) is from 90:10 to about 80:20. 
     
     
         10 . The lubricant according to  claim 1 , wherein the lubricant further comprises an optional additive chosen amongst a neutral detergent, an overbased detergent, an anti-wear additive, a fatty amine soluble in lubricant, a polymer, a dispersing additive, an anti-foaming additive or a mixture thereof. 
     
     
         11 . The lubricant according to  claim 1 , wherein the lubricant composition is a marine lubricant having a BN determined according to the standard ASTM D-2896 of at most 50 milligrams of potassium hydroxide per gram of the lubricant composition. 
     
     
         12 . The lubricant according to  claim 1 , wherein the lubricant composition is a marine lubricant having a BN determined according to the standard ASTM D-2896 of at least 50 milligrams of potassium hydroxide per gram of the lubricant composition. 
     
     
         13 . A method for lubricating two-stroke marine engines comprising applying a composition according to  claim 1  as a lubricant composition to at least one component of a two-stroke marine engine. 
     
     
         14 . The method according to  claim 13 , for reducing the disruption of the lubricant jet before its impact. 
     
     
         15 . The method according to  claim 14 , for reducing the disruption of the lubricant jet before its impact onto a pistons ring pack system.