US 12,110,469 B2
Polymer composition, lubricant additive, viscosity index improver, lubricant composition, method for producing polymer composition, and method for producing macromonomer
Hiroki Fukuta, Tokyo (JP); Katsufumi Mochizuki, Tokyo (JP); Fumiko Fujie, Tokyo (JP); Takahiro Mukuda, Tokyo (JP); Hiroshi Niino, Tokyo (JP); Eiko Okamoto, Tokyo (JP); Kazunari Matsumura, Tokyo (JP); Hiroko Shinada, Tokyo (JP); and Hiroki Hamamoto, Tokyo (JP)
Assigned to Mitsubishi Chemical Corporation, Tokyo (JP)
Filed by Mitsubishi Chemical Corporation, Tokyo (JP)
Filed on Sep. 9, 2022, as Appl. No. 17/941,154.
Application 17/941,154 is a continuation of application No. PCT/JP2021/012531, filed on Mar. 25, 2021.
Claims priority of application No. 2020-055130 (JP), filed on Mar. 25, 2020; and application No. 2020-055131 (JP), filed on Mar. 25, 2020.
Prior Publication US 2023/0063756 A1, Mar. 2, 2023
Int. Cl. C10M 145/14 (2006.01); C10M 169/04 (2006.01); C10M 177/00 (2006.01)
CPC C10M 145/14 (2013.01) [C10M 169/041 (2013.01); C10M 177/00 (2013.01); C10M 2209/084 (2013.01)] 23 Claims
OG exemplary drawing
 
1. A polymer composition, comprising a (meth)acrylic copolymer A including;
a constituent unit derived from an alkyl methacrylate a1 of an alkyl group having 5 to 14 carbon atoms,
a constituent unit derived from an alkyl acrylate a2 of an alkyl group having 5 to 14 carbon atoms, and
a constituent unit derived from an alkyl acrylate a3 of an alkyl group having 1 to 4 carbon atoms,
wherein the (meth)acrylic copolymer A further comprises a graft copolymer structure including,
a constituent unit derived from a vinyl radical polymerizable monomer m1 as a main chain of the graft copolymer structure, and
a constituent unit derived from a macromonomer M other than the vinyl radical polymerizable monomer m1 as a branch component of the graft copolymer structure,
a differential distribution value in a differential molecular weight distribution curve of the polymer composition, as measured by gel permeation chromatography, satisfies Equation 1, and
a maximum value of a normalized back-scattering intensity of a 35 wt % base oil solution of the polymer composition is 40 cm−1 or more, where a size q of a scattering vector of small-angle X-ray scattering at 25° C. is in a range of 0.07 nm−1 or more and 2 nm−1 or less,
dMp30/dMp≥0.65  Equation 1
wherein in Equation 1,
dMp30 is a differential distribution value of molecular weight corresponding to 30% of a peak top molecular weight, as measured by gel permeation chromatography,
dMp is a differential distribution value of the peak top molecular weight, as measured by gel permeation chromatography, and
the 35 wt % base oil solution uses API standard Group III or Group III Plus as a base oil.