HYDROGENATED DIOLEFIN-LOWER ALKYL ACRYLATE OR METHACRYLATE VISCOSITY INDEX IMPROVING COPOLYMERS FOR LUBRICATING OILS

摘要

- i Patent Application of JOSEPH MARTIN BOLLINGER for HYDROGENATED DIOLEFIN-LOWER ALKYL ACRYLATE OR METHACRYLATE VISCOSITY INDEX IMPROVING COPOLYMERS FOR LUBRICATING OILS D.N. 81-60 MSA/ets This invention relates to hydrogenated diolefin-lower alkyl acrylate or methacrylate copolymers and the use of these copolymers to improve the viscosity index (VI) of lubricating oils. The preferred copolymer is a fully hydrogenated, high molecular weight copolymer of 1,3butadiene and methyl methacrylate containing at least about 71 mole percent 1,3-butadiene. A pour point depressant, VI improving polymer additive for lubricating oils is provided by incorporating a higher alkyl methacrylate in the copolymer. Further, a dispersant VI improving copolymer for lubricating oils and a dispersant for hydrocarbon fuels prepared by graft polymerizing a polar, nitrogen-containing graft monomer onto the VI improver or pour point depressant VI improver is also provided.