	US 12,275,845 B2
	Diene rubber and rubber composition
Yoshikazu Ueno, Kamisu (JP); and Daisuke Koda, Kamisu (JP)
Assigned to KURARAY CO., LTD., Kurashiki (JP)
Appl. No. 17/612,824
Filed by KURARAY CO., LTD., Kurashiki (JP)
PCT Filed May 21, 2020, PCT No. PCT/JP2020/020051 § 371(c)(1), (2) Date Nov. 19, 2021, PCT Pub. No. WO2020/235619, PCT Pub. Date Nov. 26, 2020.
Claims priority of application No. 2019-095781 (JP), filed on May 22, 2019.
Prior Publication US 2022/0220286 A1, Jul. 14, 2022
Int. Cl. C08L 7/00 (2006.01); B60C 1/00 (2006.01); B60C 11/00 (2006.01)

CPC C08L 7/00 (2013.01) [B60C 1/0016 (2013.01); B60C 11/0008 (2013.01); B60C 2001/0058 (2013.01); B60C 2001/0066 (2013.01); B60C 2011/0025 (2013.01)]

20 Claims

1. A diene rubber, comprising:

butadiene units,

wherein the diene rubber has a weight average molecular weight in a range of from 5,000 to 19,000,

the diene rubber satisfies (i) to (iii)

β_cp>0 (i),

β₁₂>40 (ii), and

β_cp/(β₁₂−40)≤2 (iii), and

with respect to all the butadiene units present in the diene rubber, β₁₂is mol % of 1,2-bonded butadiene units, and β_cpis mol % of structural units of formula (1)