Patent ID: 7820607
Filing Date: 2010-10-26
Classification: C08F,C10M,C10N

Abstract:
1. A viscosity modifier for lubricating oils comprising an ethylene/α-olefin copolymer (B) which comprises: (i) a structural unit derived from ethylene; (ii) a structural unit derived from an α-olefin having 3 to 19 carbon atoms; and (iii) a structural unit derived from a higher α-olefin having 4 to 20 carbon atoms whose carbon number is by one or more larger than that of the structural unit derived from an α-olefin having 3 to 19 carbon atoms, and has the following properties of (1), (2), and (4): (1) it contains 25 to 46.2 mol % of the structural unit (i) derived from ethylene, 15 to 55 mol % of the structural unit (ii) derived from an α-olefin having 3 to 19 carbon atoms, and 9 to 40 mol % of the structural unit (iii) derived from a higher α-olefin having 4 to 20 carbon atoms, wherein the total molar amount of the structural units (i), (ii), and (iii) is 100 mol %; (2) the intrinsic viscosity ([η]) is in the range of 1.5 to 5.0 dl/g as measured in decalin at 135° C.; (4) the heat of fusion (ΔH) as measured by DSC is 5.0 J/g or less.