Polymer composition, lubricant additive, viscosity index improver, lubricant composition, method for producing polymer composition, and method for producing macromonomer

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.