Copolymer of 1,3,7-octatriene and isoprene, hydride thereof, and method for producing said copolymer

2:

• A copolymer comprising a structural unit derived from 1,3,7-octatriene and a structural unit derived from isoprene, the copolymer having a molecular weight distribution (Mw/Mn) smaller than a value determined according to the following formula (i):
• 3.1569×10−6×[Weight average molecular weight (Mw)]+1.1945 (i).

3:

• A copolymer comprising a structural unit derived from 1,3,7-octatriene and a structural unit derived from isoprene, the copolymer having not only a content of the structural unit derived from 1,3,7-octatriene of more than 21.0 mol % relative to a total amount of the structural unit derived from 1,3,7-octatriene and the structural unit derived from isoprene, but also a molecular weight distribution (Mw/Mn) thereof of less than 2.06.

4:

• The copolymer according to claim 1, having a weight average molecular weight (Mw) of 5,000 to 500,000.

5:

• The copolymer according to claim 1, having a weight average molecular weight (Mw) of 20,000 to 500,000.

6:

• The copolymer according to claim 1, having a weight average molecular weight (Mw) of 50,000 to 500,000.

7:

• The copolymer according to claim 1, having a weight average molecular weight (Mw) of 210,000 to 500,000.

8:

• The copolymer according to claim 1, not having a living anionic active species at a molecular end thereof.

9:

• The copolymer according to claim 1, having a living anionic active species at a molecular end thereof.

10:

• A copolymer comprising a structural unit derived from 1,3,7-octatriene and a structural unit derived from isoprene, the copolymer having a living anionic active species at a molecular end thereof and having a molecular weight distribution (Mw/Mn) of 2.50 or less.

11:

• The copolymer according to claim 10, having a weight average molecular weight (Mw) of 5,000 to 500,000.

12:

• The copolymer according to claim 1, further comprising a structural unit derived from a conjugated diene compound having 6 or more carbon atoms.

13:

• The copolymer according to claim 12, wherein the conjugated diene compound having 6 or more carbon atoms is at least one selected from the group consisting of 2,3-dimethyl-1,3-butadiene, 4,5-diethyl-1,3-butadiene, 2-phenyl-1,3-butadiene, 2-hexyl-1,3-butadiene, 2-benzyl-1,3-butadiene, 2-p-toluyl-1,3-butadiene, 2-methyl-1,3-pentadiene, 3-methyl-1,3-pentadiene, 2,3-dimethyl-1,3-pentadiene, 2,3-diethyl-1,3-pentadiene, 1,3-hexadiene, 2,3-dimethyl-1,3-hexadiene, 2,3-diethyl-1,3-heptadiene, 3-butyl-1,3-octadiene, 2,3-dimethyl-1,3-octadiene, 4,5-diethyl-1,3-octadiene, 1,3-cyclohexadiene, and myrcene.

14:

• A hydride of the copolymer according to claim 1.

16:

• The method of claim 15, wherein the 1,3,7-octatriene has a purity, as determined by gas chromatography, of 98.5% or more.

17:

• The method of claim 15, wherein the anionic polymerization is carried out in the presence of a Lewis base.

18:

• The method of claim 17, wherein a molar ratio of the Lewis base to a polymerization initiator used for the anionic polymerization [(Lewis base)/(polymerization initiator)] is from 0.01 to 1,000.

19:

• The method of claim 17, wherein the Lewis base is a compound having at least one selected from the group consisting of an ether bond and a tertiary amino group in a molecule thereof.

20:

• The method of claim 17, wherein the Lewis base is a compound having one atom having an unshared electron pair.

21:

• The method of claim 17, wherein the Lewis base is a compound having two or more atoms having an unshared electron pair.

22:

• The method of claim 21, wherein the Lewis base has multidentate properties.

23:

• The method of claim 15, wherein a solid content concentration of a reaction liquid obtained after completion of the anionic polymerization is from 10 to 80% by mass.

24:

• The method of claim 15, wherein the anionic polymerization is carried out at −50 to 200° C.

25:

• The method of claim 15, wherein a conversion of the 1,3,7-octatriene after completion of the anionic polymerization, as determined by gas chromatography, is 80.0% or more.

26:

• The method of claim 15, wherein a conversion of the 1,3,7-octatriene after completion of the anionic polymerization, as determined by gas chromatography, is 88.0% or more.