Patent ID: 6458749
Filing Date: 2002-10-01
Classification: C10M,C10N

Abstract:
A method for maintaining low temperature fluidity of a lubricating oil composition comprising adding from 0.03 to 3 percent, based on total lubricating oil composition weight, of a first [P1] and a second [P2] polymer to the lubricating oil composition wherein:(a) the first polymer [P1] comprises zero to 15 percent monomer units selected from one or more (C1-C6)alkyl (meth)acrylates, 30 to 75 percent monomer units selected from one or more (C7-C15)alkyl (meth)acrylates and 25 to 70 percent monomer units selected from one or more (C16-C24)alkyl (meth)acrylates, based on total first polymer weight, and has a weight average molecular weight from 250,000 to 1,500,000; (b) the second polymer [P2] comprises zero to 15 percent monomer units selected from one or more (C1-C6)alkyl (meth)acrylates, 75 to 100 percent monomer units selected from one or more (C7-C15)alkyl (meth)acrylates and zero to 25 percent monomer units selected from one or more (C16-C24)alkyl (meth)acrylates, based on total second polymer weight, and has a weight average molecular weight from 10,000 to 1,500,000; (c) the first polymer [P1] has a weight average molecular weight at least 50,000 greater than that of the second polymer [P2]; and (d) the first and second polymers are combined in a weight ratio ([P1]/[P2]) of 5/95 to 75/25.