The present invention provides a lubricating oil composition comprising: (A) a lubricant base oil including at least one type selected from mineral oil, PAO, and GTL (gas-to-liquid) base oils; (B) a compound having a structure obtained by independently subjecting propylene oxide to addition polymerization with an alcohol or a structure obtained by subjecting a combination of propylene oxide with ethylene oxide and/or butylene oxide to addition polymerization with an alcohol, and being configured so that polyalkylene glycol (PAG) with an oxygen/carbon weight ratio of 0.35 or more and less than 0.45 and/or one or both terminal hydroxyl groups in the polyalkylene glycol (PAG) are blocked; and (C) a fatty acid ester having an oxygen/carbon weight ratio of 0.05 to 0.35.

The presently claimed invention relates to a gear oil composition having a kinematic viscosity at 40? C. in the range of ?68 to ?1000 cSt when measured in accordance with ASTM D445. The gear oil composition is useful as a lubricant in a gear box, especially in a wind turbine gear box.

The presently claimed invention relates to a gear oil composition having a kinematic viscosity at 40? C. in the range of ?68 to ?1000 cSt when measured in accordance with ASTM D445. The gear oil composition is useful as a lubricant in a gear box, especially in a wind turbine gear box.

A lubricant composition with a comb polymer and a synthetic base oil has improved viscosity characteristics at low operating temperatures. In addition, a comb polymer can be used for producing a lubricant having an R-factor of less than or equal to 8, wherein the R-factor is defined as the ratio of the kinematic viscosity at 20 C. and the kinematic viscosity at +20 C.

A lubricant composition with a comb polymer and a synthetic base oil has improved viscosity characteristics at low operating temperatures. In addition, a comb polymer can be used for producing a lubricant having an R-factor of less than or equal to 8, wherein the R-factor is defined as the ratio of the kinematic viscosity at 20 C. and the kinematic viscosity at +20 C.

A gear oil composition that has a kinematic viscosity at 40? C. in the range of ?68 to ?1000 csdt when measured in accordance with ASTM D445 can be made. The gear oil composition is useful as a lubricant in a gear box, especially in a wind turbine gear box.

A gear oil composition that has a kinematic viscosity at 40? C. in the range of ?68 to ?1000 csdt when measured in accordance with ASTM D445 can be made. The gear oil composition is useful as a lubricant in a gear box, especially in a wind turbine gear box.

A blend for lubricating a surface includes a lubricant and a polyepoxide co(ter)polymer additive mixed with the lubricant. The polyepoxide co(ter)polymer additive includes a first block having monomer M.sub.1 and a second block having monomer M.sub.2. The first monomer M.sub.1 includes hexene oxide, HO, or octene oxide, OO, and the second monomer M.sub.2 includes propylene oxide, PO.

A capped oil soluble polyalkylene glycol has the following structure: R.sup.1O-(AO).sub.nR.sup.2 where: R.sup.1 is a linear or branched alkyl or aryl with one to 18 carbon atoms; AO refers to residuals of monomers selected from 1,2-butylene oxide and 1,2-propylene oxide selected so that at least 50 weight-percent of the (AO).sub.n component is 1,2-butylene oxide residuals; n is selected to provide a kinematic viscosity at 100 degrees Celsius of less than 5 centiStokes for the non-capped polyalkylene glycol; and R.sup.2 is a linear or branched alkyl or aryl having from 1-8 carbon atoms and wherein the capped oil soluble polyalkylene glycol is characterized by having a kinematic viscosity of less than 4.5 centiStokes at 100 degrees Celsius and a viscosity index of greater than 150.

A capped oil soluble polyalkylene glycol has the following structure: R.sup.1O-(AO).sub.nR.sup.2 where: R.sup.1 is a linear or branched alkyl or aryl with one to 18 carbon atoms; AO refers to residuals of monomers selected from 1,2-butylene oxide and 1,2-propylene oxide selected so that at least 50 weight-percent of the (AO).sub.n component is 1,2-butylene oxide residuals; n is selected to provide a kinematic viscosity at 100 degrees Celsius of less than 5 centiStokes for the non-capped polyalkylene glycol; and R.sup.2 is a linear or branched alkyl or aryl having from 1-8 carbon atoms and wherein the capped oil soluble polyalkylene glycol is characterized by having a kinematic viscosity of less than 4.5 centiStokes at 100 degrees Celsius and a viscosity index of greater than 150.