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US4255296A Expired / Lapsed US ⏱️ 0.0 years remaining

Polybutadiene rubber composition

Assignee: Bridgestone Corp
•
Filing: 1978-11-28
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Granted: 1981-03-10
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Expires: 1998-11-28
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Abstract

Abstract This invention relates to a composition comprising a polybutadiene rubber containing a polymer obtained by block or graft polymerization of cis-1,4-polybutadiene with syndiotactic (syn)-1,2-polybutadiene, alone or blended with the other diene rubber, said syn-1,2-polybutadiene being crystallized and in a short fiber-like shape, and a breaking resistance characteristic and reinforcement characteristic being considerably improved by specifying the diameter and length of said short fiber, which is suitable for various parts of tire or industrial materials, and further relates to a composition of said polybutadiene rubber to which a carbon black is added for preferably used as a chafer or tread of tire, and still further relates to said composition to which a carbon black and an antioxidant are added for preferably used as a rubber blend composition for side wall.

Inventors

  • 👤 Masaki Ogawa
  • 👤 Tamio Araki

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 11:21
CPC Classifications
C; C08; C08L; C08L21/00; C08L25/00; C08L25/02; C08L25/04; C08L25/08; C08L25/10; C08L7/00; C08L9/00; C08K; C08K3/00; C08K3/02; C08K3/04; C08K7/00; C08K7/02; C08L51/00; C08L51/04; C08L53/00; C08L9/06

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 72 words
A composition comprising a polybutadiene rubber containing a polymer obtained by block or graft polymerization of cis-1,4-polybutadiene with syndiotactic(syn)-1,2-polybutadiene in which a microstructure is of 78 to 93% by weight of cis-1,4-structure and 6 to 20% by weight of syn-1,2-structure, at least 40% by weight of said syn-1,2-polybutadiene being crystallized and in a short fiber-like shape having an average diameter of 0.05 to 1μ and an average length of 0.8 to 10μ.
Claim 2
Dependent Claim 72 words
A composition comprising a polybutadiene rubber containing a polymer obtained by block or graft polymerization of cis-1,4-polybutadiene with syndiotactic(syn)-1,2-polybutadiene in which a microstructure is of 78 to 93% by weight of cis-1,4-structure and 6 to 20% by weight of syn-1,2-structure, at least 40% by weight of said syn-1,2-polybutadiene being crystallized and in a short fiber-like shape having an average diameter of 0.05 to 1μ and an average length of 0.8 to 10μ.
Claim 3
Dependent Claim 35 words
A composition as claimed in claim 1, which further comprises at least one other diene rubber selected from the group consisting of natural rubber, polyisoprene rubber, styrene-butadiene copolymer and cis-1,4-polybutadiene rubber, and an inorganic filler.
Claim 4
Dependent Claim 30 words
A composition as claimed in claim 2, in which 20 to 120 parts by weight of the inorganic filler is blended per 100 parts by weight of the polybutadiene rubber.
Claim 5
Dependent Claim 27 words
A composition as claimed in claim 2, in which the ratio of average fiber length to average diameter of the syn-1,2-polybutadiene short fiber is at least 8.
Claim 6
Dependent Claim 103 words
A composition as claimed in claim 4, in which a carbon black as said filler having an iodine absorption number (IA) of 76 mg/g or more and a dibutyl phthalate oil absorption number (DBP) of 90 ml/100 g or more is combined by 40 to 100 parts by weight relative to 100 parts by weight of blended polybutadiene rubber prepared by blending 40 to 95 parts by weight of said polybutadiene rubber and 5 to 60 parts by weight of said other diene rubber, so that a pico abrasion index defined by ASTM D2228 of the polybutadiene rubber composition is 210 or more.
Claim 7
Dependent Claim 33 words
A composition as claimed in claim 5, in which the IA of the carbon black is 86 mg/g or more and the DBP of the carbon black is 105 ml/100 g or more.
Claim 8
Dependent Claim 103 words
A composition as claimed in claim 4, in which a carbon black as said filler having an IA of 30 to 90 mg/g and a DBP of 130 ml/100 g or less is combined by 30 to 100 parts by weight relative to 100 parts by weight of blended polybutadiene rubber prepared by blending 40 to 95 parts by weight of said polybutadiene rubber and 5 to 60 parts by weight of said other diene rubber, and an antioxidant and p-phenylenediamine group is further combined by 0.5 to 8 parts by weight relative to 100 parts by weight of said blended polybutadiene rubber.
Claim 9
Dependent Claim 29 words
A composition as claimed in claim 7, in which the antioxidant of p-phenylenediamine group is at least one selected from the group consisting of N-phenyl-N'-isopropyl-p-phenylenediamine, N,N'-diphenyl-p-phenylenediamene, N-phenyl-N'-(2,4-dimethyl)butyl-p-phenylenediamine and N,N'-di-2-naphthyl-p-phenylenediamine.
Claim 10
Dependent Claim 75 words
A composition as claimed in claim 4, in which a carbon black as said filler having IA of 60 mg/g or more and a DBP of 70 ml/100 g or more is combined by 30 to 100 parts by weight relative to 100 parts by weight of blended polybutadiene rubber prepared by blending 40 to 95 parts by weight of said polybutadiene rubber and 5 to 60 parts by weight of said other diene rubber.
Claim 11
Dependent Claim 21 words
A composition as claimed in claim 9, in which a weight average molecular weight of said cis-1,4-polybutadiene is 350,000 or more.

References Cited (Backward Citations)

US3140278A Cited
US3696062A Cited
US3827991A Cited
US3852225A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1984-03-09 1984-09-08 1985-03-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1988-03-09 1988-09-08 1989-03-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1992-03-09 1992-09-08 1993-03-10 $7700.00 Window Closed / Lapsed

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