POLYBUTADIENE

• US 20170015766A1
• Filed: 02/19/2015
• Published: 01/19/2017
• Est. Priority Date: 03/31/2014
• Status: Active Grant

• Current Assignee: UBE Elastomer Company Limited (UBE Corporation)
• Original Assignee: UBE Industries Limited (UBE Corporation)
• Inventors: AMBE, Mitsuharu, KANOU, Yuuto, SHODA, Takeshi
• Granted Patent: US 9,676,881 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: C08F 136/06 Butadiene
• CPC Class Codes: C08F 36/06 Butadiene
• CPC Class Codes: C08F 4/6022 Component of C08F4/60 containing at least two different metals
• CPC Class Codes: C08F 4/70 Iron group metals, platinum group metals or compounds thereof
• CPC Class Codes: C08F 4/7096 Cobalt or compounds thereof
• CPC Class Codes: C08K 3/36 Silica
• CPC Class Codes: C08K 5/54 Silicon-containing compounds C08K5/0091 takes precedence
• CPC Class Codes: C08L 9/00 Compositions of homopolymers or copolymers of conjugated diene hydrocarbons
• CPC Class Codes: C08L 9/06 Copolymers with styrene

Abstract

The present invention provides a polybutadiene having improved workability and abrasion resistance. A polybutadiene according to the present invention has: (A) a Mooney viscosity (ML_{1+4,100° C.}) being 43 or more; (B) a ratio (Tcp/ML_{1+4,100° C.}) of 5 wt % toluene solution viscosity (Tcp) to Mooney viscosity (ML_{1+4,100° C.}) being 0.9 to 2.3; (C) a stress relaxation time (T80) being 10.0 to 40.0 seconds, which is a time until a torque is attenuated by 80% when the torque at the end of ML_{1+4,100° C.}measurement is 100%; and (D) a molecular weight distribution (Mw/Mn) being 2.50 to 4.00.

Claims

1. A polybutadiene, which is produced by using a cobalt catalyst, having:

(A) a Mooney viscosity (ML<sub>1+4,100°

C.</sub>) being 43 to 70;

(B) a ratio (Tcp/ML<sub>1+4,100°

C.</sub>) of 5 wt % toluene solution viscosity (Tcp) to Mooney viscosity (ML<sub>1+4,100°

C.</sub>) being 0.9 to 1.7;

(C) a stress relaxation time (T80) being 10.0 to 40.0 seconds, which is a time until a torque is attenuated by 80% when the torque at the end of ML<sub>1+4,100°

C.</sub>measurement is 100%;

(D) a molecular weight distribution (Mw/Mn) being 2.50 to 4.00; and

(F) a ratio of cis-structure in microstructural analysis being 94.0 to 98 mol %.

2. The polybutadiene according to claim 1, further having:

(E) a weight average molecular weight (Mw) being 40.0×

10⁴ to 75.0×

10⁴,

(G) a 5 wt % toluene solution viscosity (Tcp) being 42 to 160; and

(H) a number average molecular weight (Mn) being 12.5×

10⁴ to 30.0×

10⁴.

3. (canceled)