EP0054911A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Random styrene-butadiene copolymer rubber
Assignee: Asahi Kasei Corp
•
Filing: 1981-12-16
•
Granted: —
•
Expires: 2001-12-16
Abstract
Abstract A random SBR having excellent tensile strength, resilience, and abrasion resistance as well as a reduced heat buildup property, which comprises 10% to 40% by weight of styrene units and the balance of butadiene units and has a Mooney viscosity of 30 to 150; a content of butadiene units having 1,2-vinyl structure of 60% or less; a ratio Mw/Mn of from 1.2 to 3.5; and a content of isolated styrene units of 40% or more and a content of another styrene units in long chain block form of 5% or less, both contents being determined by decomposing the copolymer with ozone and by applying a gel permeation chromatographic analysis to the ozone decomposition product.
Inventors
- 👤 Yasuo Hattori
- 👤 Hideo Morita
- 👤 Yoshihiro Inoki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 09:43
CPC Classifications
C; C08; C08F; C08F236/00; C08F236/02; C08F236/04; C08F236/10; C08K; C08K3/00; C08K3/02; C08K3/04; C08L; C08L9/00; C08L9/06
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
231 words
A process for producing a random styrene-butadiene copolymer rubber, comprising 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight Mw to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis, characterized in that a mixture of predetermined amounts of styrene, butadiene, and an inert diluent is continuously fed into a polymerization region in which the styrene and butadiene are copolymerized in the presence of a catalyst consisting of an organic lithium compound and a Lewis base at a temperature of 80°C or more, preferably 90°C or more, while the polymerization mixture is vigorously agitated.
Claim 2
Dependent Claim
231 words
A process for producing a random styrene-butadiene copolymer rubber, comprising 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight Mw to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis, characterized in that a mixture of predetermined amounts of styrene, butadiene, and an inert diluent is continuously fed into a polymerization region in which the styrene and butadiene are copolymerized in the presence of a catalyst consisting of an organic lithium compound and a Lewis base at a temperature of 80°C or more, preferably 90°C or more, while the polymerization mixture is vigorously agitated.
Claim 3
Dependent Claim
43 words
A process according to claim 1, characterized in that a plurality of polymerization regions are connected to each other in series and that the proportions of the amounts of styrene and butadiene supplied into the polymerization regions are the same as each other.
Claim 4
Dependent Claim
36 words
A process according to claim 1 or 2,characterized in that the polymerization mixture containing styrene, butadiene and the inert diluent further contains an additional component consisting of at least one polymerizable monomer selected from allene compounds.
Claim 5
Dependent Claim
192 words
A rubber composition, containing a random styrene-butadiene copolymer rubber which comprises 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight MW to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis, in the form of a blend with natural rubber and/or another synthetic rubber or in the form of a blend with an usual plastic.
Claim 6
Dependent Claim
192 words
A rubber composition, containing a random styrene-butadiene copolymer rubber which comprises 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight MW to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis, in the form of a blend with natural rubber and/or another synthetic rubber or in the form of a blend with an usual plastic.
Claim 7
Dependent Claim
211 words
Rubber composition, containing a random styrene-butadiene copolymer rubber, which comprises 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight MW to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis in an amount of at least 30 % by weight, carbon black in an amount of 20 to 120 parts by weight per 100 parts by weight of said copolymer rubber and a vulcanizing agent in a necessary amount for vulcanizing said copolymer rubber.
Claim 8
Dependent Claim
211 words
Rubber composition, containing a random styrene-butadiene copolymer rubber, which comprises 10 % to 40 % by weight of styrene units and the balance comprising butadiene units and having a Mooney viscosity of 30 to 150, which copolymer rubber is characterized in that the content of the butadiene units having a 1,2-vinyl structure is 60 % or less based on the entire amount of said butadiene units in said copolymer; the heterogeneity index represented by the ratio of the weight average molecular weight MW to number average molecular weight Mn of said copolymer is in the range of from 1.2 to 3.5; the content of the isolated styrene units is 40% or more and the content of the styrene units in the form of long chain blocks is 5 % or less, each based on the entire weight of said styrene units in said copolymer, which contents have been determined by decomposing said copolymer with ozone and by subjecting said ozone-decomposition product to a gel permeation chromatographic analysis in an amount of at least 30 % by weight, carbon black in an amount of 20 to 120 parts by weight per 100 parts by weight of said copolymer rubber and a vulcanizing agent in a necessary amount for vulcanizing said copolymer rubber.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.