BRANCHED POLYMERS AS VISCOSITY AND/OR FRICTION MODIFIERS FOR LUBRICANTS

摘要

Embodiments of branched polymer lubricant additives comprise a branched polymer and, when combined with a lubricant base at a concentration from 1 wt % to 50 wt %, provide (i) a viscosity index ≧150, (ii) that is at least 10% less than a coefficient of friction of the lubricant base alone in contact with a component of a device during operation of the device at a temperature within a range of 20 to 100° C., or (iii) both (i) and (ii).

主权项

1. A branched polymer, comprising:
(a) a hyperbranched polar core having a functionality of at least 3 and comprising a plurality of heteroatoms, and a plurality of polymeric or non-polymeric arms bonded to the hyperbranched polar core, wherein when the functionality is within a range of 3-21 and the plurality of arms is polymeric, the hyperbranched polar core is not a cyclotetrasiloxane derivative, a cyclophosphazene derivative, a calixarene derivative, a cyclodextrin derivative, or a saccharide derivative; (b) an aryl polyester core derived from ABx monomers, ABx+By monomers, or A2+By monomers, where x≧2 and y≧3, the aryl polyester core having a degree of branching within a range of 0.1 to 0.9, and a plurality of polymeric or non-polymeric arms bonded to the aryl polyester core; or (c) a branched polyolefin including first monomeric units derived from an olefin and second monomeric units derived from polar monomers, each polar monomer including at least one heteroatom, wherein when the olefin is ethylene, the polar monomers are not an alkenyl ether, methyl-9-decenoate, or methyl 2,2-dimethylpent-4-enoate.