TECHNOLOGY FOCUS - POLYMERS - Preparation (disclosed): The high-molecular compound is prepared by copolymerizing a carbon cluster structure-containing compound of formula: R1-C(=CH2)-X1-Y'1-(-(X2-Y'2)-)n-W'-FLN (II) and an unsaturated compound of formula: R2-C(=CH2)-R3 (III) by performing atom transfer radical polymerization.R2,R3=alkyl, alkoxy, alkylthio, monovalent heterocyclyl, aryl, aryloxy, acyl or acyloxy (all optionally substituted), alkoxycarbonyl, or carboxy.Preferred Composition: The high-molecular compound further has a methylene group-containing repeating unit (B) of formula: -(-CH2-C(-R2)(-R3)-)- (IV). The content of repeating unit (A) in the high-molecular compound is 70 mol% or less with respect to total amount of repeating units contained in the polymer. The content of carbon cluster structure in the high-molecular compound is 60 %mass or less. Preferred Definitions:    FLN=60C fullerene structure, 70C fullerene structure, phenyl-61C-butyric acid methyl ester structure, or phenyl-71C-butyric acid methyl ester structure;and    W'=nitrogen atom.    EXAMPLE - 0.578 mL Methyl methacrylate, 0.123 g 6-chlorohexyl methacrylate, 6 mL toluene, and 49.3 mg 2,2'-azoisobutyronitrile were added to test tube, and mixed, to obtain a mixture. The mixture was frozen in liquid nitrogen, and deaerated using a vacuum pump. Nitrogen gas was introduced into the test tube at normal temperature. The mixture was reacted at 60 degrees C and cooled to room temperature. The cooled mixture was added to 200 mL hexane and centrifuged, to recover chlorine-containing compound of formula (V) as deposits. 500 mg Chlorine-containing compound was dissolved in 2 mL N,N-dimethylformamide. 0.260 g Sodium azide was added to the reaction liquid, and reacted at 60 degrees C for 24 hours. The resultant liquid was concentrated under reduced pressure, and poured into a mixed solvent containing 40 mL water and 160 mL methanol. The precipitates were recovered by filtration and vacuum-dried at room temperature for 12 hours, to obtain azide group-containing compound of formula (VI). 80 mg Azide group-containing compound and 23.9 mg 60C fullerene were dissolved in chlorobenzene, to obtain a mixed solution. The mixed solution was frozen in liquid nitrogen, and deaerated. The reaction liquid was refluxed in nitrogen gas atmosphere for 48 hours, and concentrated under reduced pressure. The residue was dissolved in 2 mL tetrahydrofuran, and the insoluble material containing unreacted 60C fullerene was removed by centrifugation. The supernatant liquid was poured into 200 mL hexane, and centrifuged, to recover the deposits. The deposits were dissolved in 2 mL tetrahydrofuran, and precipitated. The precipitates were vacuum-dried at 40 degrees C for 12 hours, to obtain fullerene compound of formula (VII), with yield of 93% and carbon cluster structure content of 25.7%.