Abstract: The invention provides dispersants and dispersant viscosity index improvers which include polymers of conjugated dienes which have been hydrogenated and functionalized. The dispersant substances include compositions including a copolymer of two different conjugated dienes, a copolymer of a p-alkylstyrene and a conjugated diene, or a homopolymer of a conjugated diene. The polymers are selectively hydrogenated to produce polymers which have highly controlled amounts of unsaturation, permitting highly selective functionalization. Also provided are lubricant fluids, such as mineral and synthetic oils, which have been modified in their dispersancy and/or viscometric properties by means of the dispersant substances of the invention. Also provided are methods of modifying the dispersancy and/or viscometric properties of lubricating fluids such as mineral and synthetic lubricating oils. The dispersant substances may also include a carrier fluid to provide dispersant concentrates.

Abstract: An epoxidized linear block copolymer which prior to epoxidation comprises at least one triblock I--B--I, wherein I is a block of a polymerized conjugated diene of at least 5 carbon atoms, such as isoprene, and B is a block of a polymer of a conjugated diene, different from that polymerized to form the I blocks, of at least 4 carbon atoms, such as 1,3-butadiene. The B block may be selectively hydrogenated before or after epoxidation so that they contain substantially no ethylenic unsaturation, while the epoxidation reaction forms epoxy groups from double bonds in the I blocks. Also disclosed is an alternative epoxidized solid linear block copolymer which prior to epoxidation contains at least one triblock wherein the first polymer block is a copolymer of an aryl-substituted olefin, such as styrene, and the conjugated diene used to polymerize the block I, the second or middle block is a polymer of the diene used to polymerize the block B, and the third polymer block is the same as the first polymer block.

Abstract: This invention is directed to a synergistic antioxidant system for use in oils comprising a phenylated naphthylamine, a sulfoxide compound, and, optionally, an oligodynamic amount of copper.