Use of an Ethylene/alpha-olefin Copolymer as a Base Oil in a Lubricant Composition

摘要

1. An ethylene/ alpha -olefin copolymer, which: (1) comprises 30 to 80% by mol ethylene and 20 to 70% by mol C3 to 10 alpha -olefin; (2) has a number-average molecular weight (Mn), as determined by gel permeation chromatography (GPC) of 500 to 12,000 and a molecular weight distribution (Mw/Mn) of 3 or less; (3) has a kinetic viscosity at 100 DEG C of from 10 to 5,000 mm<2>/s; (4) has at least one unsaturated bond at a molecular terminal of at least 95% of the polymer chains; and (5) has a B value, as determined by formula (I), of from 1.0 to 2.0: <DF NUM="(I)">B = POE/(2PO.PE) </DF> wherein PE is the molar fraction of the ethylene unit in the copolymer, PO is the molar fraction of the alpha -olefin unit in the copolymer, and POE is the proportion of the number of alpha -olefin/ethylene sequences to the number of all the dyad sequences in the copolymer.