beta-Pinene isobutylene → Beta-Pinene

127 parts by mass of cyclohexane, and 25 parts by mass of β-pinene/isobutylene copolymer (A2) obtained in Reference Example 2 were put into the nitrogen-purged pressure vessel equipped with a stirrer, and stirred to thoroughly dissolve the β-pinene/isobutylene copolymer (A2). Thereafter, as the hydrogenation catalyst, 7.5 parts by mass of 5% palladium-supported carbon (product number: E1002NN/W, manufactured by Evonik Degussa Japan Co. Ltd.) was added thereto, sufficiently dispersed with stirring, and then, the inside of the pressure vessel was sufficiently purged with hydrogen, and the reaction was carried out while stirring at a temperature of 130° C. and a hydrogen pressure of 15 MPa for 25 hours, followed by a return to ambient pressure. Subsequently, the reaction solution was filtered through a 0.5 μm Teflon (registered trademark) filter to separate and remove the catalyst, reprecipitated in 3000 parts by mass of a mixed solvent of methanol/acetone (60/40 volume %), and then sufficiently dried to obtain 24 parts by mass of β-pinene-based polymer (H2). The β-pinene-based polymer (H2) thus obtained had 0.026 mole % of residual olefinic double bonds and 0.0015 mole % of residual aromatic rings, based on total units, as measured by 1H-NMR. The glass transition temperature was 95° C. Also, the ratio of the proton integral value at 6 to 8 ppm to the total proton integral value in 1H-NMR was 4.7×10−6, and the ratio of the proton integral value at 4.5 to 6 ppm to the total proton integral value was 1.0×10−5. The resulting β-pinene-based polymer (H2) had a weight average molecular weight of 53,300 and a number average molecular weight of 32,400.