Aromatic vinyl-diene copolymer, method for producing aromatic vinyl-diene copolymer, and rubber composition

{
  "publication_number": "US11008445B2",
  "country": "US",
  "kind": "B2",
  "title": "Aromatic vinyl-diene copolymer, method for producing aromatic vinyl-diene copolymer, and rubber composition",
  "abstract": "The present invention is to provide an aromatic vinyl-diene copolymer which exhibits excellent mechanical properties and wear resistance when being formed into a tire, a method for producing the aromatic vinyl-diene copolymer, and a rubber composition containing the aromatic vinyl-diene copolymer. The aromatic vinyl-diene copolymer of an embodiment of the present invention is an aromatic vinyl-diene copolymer which is a copolymer of an aromatic vinyl and a diene, wherein the content of a repeating unit derived from an aromatic vinyl is 18 mass % or greater, among repeating units derived from a diene, a proportion of a vinyl structure is 8 mol % or less, a proportion of a 1,4-trans structure is 75 mol % or less, and a proportion of a 1,4-cis structure is from 17 to 90 mol %, and a glass transition temperature is −60° C. or lower.",
  "claims": [
    "1. An aromatic vinyl-diene copolymer which is a copolymer of an aromatic vinyl and a diene, wherein a content of a repeating unit derived from an aromatic vinyl is 18 mass % or greater, among repeating units derived from a diene, a proportion of a vinyl structure is 8 mol % or less, a proportion of a 1,4-trans structure is 60 mol % or less, and a proportion of a 1,4-cis structure is from 17 to 90 mol %, a glass transition temperature is −60° C. or lower, and a terminal is modified with at least one type of modifying agent selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "2. The aromatic vinyl-diene copolymer according to claim 1, wherein the proportion of the 1,4-cis structure is 30 to 90 mol %.",
    "3. The method for producing an aromatic vinyl-diene copolymer, wherein the aromatic vinyl-diene copolymer described in claim 1 is produced by copolymerizing an aromatic vinyl and a monomer having a diene by using an initiator prepared by using an organolithium compound, an alkyl aluminum, and a metal alcoholate, and then terminating the polymerization by using an electrophile selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "4. A rubber composition comprising the aromatic vinyl-diene copolymer described in claim 1.",
    "5. The method for producing an aromatic vinyl-diene copolymer, wherein the aromatic vinyl-diene copolymer described in claim 2 is produced by copolymerizing an aromatic vinyl and a monomer having a diene by using an initiator prepared by using an organolithium compound, an alkyl aluminum, and a metal alcoholate, and then terminating the polymerization by using an electrophile selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "6. The method for producing an aromatic vinyl-diene copolymer according to claim 3, wherein a phenol compound is added to a copolymer system during the copolymerization of the monomer.",
    "7. The method for producing an aromatic vinyl-diene copolymer according to claim 5, wherein a phenol compound is added to a copolymer system during the copolymerization of the monomer.",
    "8. A rubber composition comprising the aromatic vinyl-diene copolymer described in claim 2.",
    "9. The aromatic vinyl-diene copolymer according to claim 1, wherein the terminal is modified with at least one type of modifying agent selected from the group consisting of titanium halides, cyclic silazanes, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "10. The aromatic vinyl-diene copolymer according to claim 1, wherein the terminal is modified with at least one type of modifying agent selected from the group consisting of titanium halides, tin halides, and cyclic silazanes.",
    "11. The aromatic vinyl-diene copolymer according to claim 1, wherein the proportion of the 1,4-cis structure is from 40 to 90 mol %.",
    "12. An aromatic vinyl-diene copolymer which is a copolymer of an aromatic vinyl and a diene, wherein a content of a repeating unit derived from an aromatic vinyl is 18 mass % or greater, among repeating units derived from a diene, a proportion of a vinyl structure is 8 mol % or less, a proportion of a 1,4-trans structure is 75 mol % or less, and a proportion of a 1,4-cis structure is from 40 to 90 mol %, a glass transition temperature is −60° C. or lower, and a terminal is modified with at least one type of modifying agent selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "13. The method for producing an aromatic vinyl-diene copolymer, wherein the aromatic vinyl-diene copolymer described in claim 12 is produced by copolymerizing an aromatic vinyl and a monomer having a diene by using an initiator prepared by using an organolithium compound, an alkyl aluminum, and a metal alcoholate, and then terminating the polymerization by using an electrophile selected from the group consisting of titanium halides, tin halides, cyclic silazanes, alkoxysilanes, epoxides, amines, ketones, and compounds represented by formula (N) below: wherein, R 1 represents a hydrogen atom or an alkyl group, and R 2 represents an alkylene group.",
    "14. The aromatic vinyl-diene copolymer according to claim 1, wherein the content of the repeating unit derived from the aromatic vinyl is 30 mass % or greater, and among repeating units derived from the diene, the proportion of the vinyl structure is 4 mol % or less, the proportion of the 1,4-trans structure is 30 to 60 mol %, and the proportion of the 1,4-cis structure is from 40 to 70 mol %."
  ],
  "description_excerpt": "The present invention relates to an aromatic vinyl-diene copolymer, a method for producing an aromatic vinyl-diene copolymer, and a rubber composition.\n\nAs rubber materials used in tires and the like, diene polymers, such as butadiene homopolymers (BR) and styrene-butadiene copolymers (SBR) have been conventionally known.\n\nNote that the diene polymers are produced mainly by emulsion polymerization or solution polymerization. For example, Patent Literature 1 discloses a method for producing a conjugated diene polymer in which a monomer formed from a conjugated diene or a conjugated diene and an aromatic vinyl compound is polymerized in an inert organic solvent by using a catalyst composition containing (a) a dialkoxy barium compound, (b) an organoaluminum compound, (c) an organolithium compound, (d) an amine compound represented by general formula (I) or a diamine compound represented by general formula (II), as a method for producing a diene (conjugated diene-based) polymer by solution polymerization.\n\nPatent Literature 1: JP 2712622 B\n\nIn recent years, as demands for vehicle safety increase, further enhancement in mechanical properties (e.g. hardness and strength at break) and wear resistance of tires have been desired.\n\nIn such circumstances, when inventors of the present invention produced a tire by using a copolymer of an aromatic vinyl and a diene (e.g. SBR) in accordance with Patent Literature 1, it was found that the mechanical properties and the wear resistance thereof do not necessarily satisfy the levels required recently.",
  "cpc": [
    "C08L 9/06",
    "B60C 1/0016",
    "C08C 19/00",
    "C08C 19/22",
    "C08C 19/25",
    "C08C 19/44",
    "C08F 212/08",
    "C08F 236/06",
    "C08F 236/10",
    "C08F 4/54",
    "C08K 3/011",
    "C08K 3/013",
    "C08K 3/04",
    "C08K 3/16",
    "C08K 3/36",
    "C08K 5/0025",
    "C08K 5/1515",
    "C08K 5/3412",
    "C08K 5/56"
  ],
  "ipc": [
    "C08F 236/10",
    "C08K 3/16",
    "C08K 5/1515",
    "C08K 5/3412",
    "C08K 5/56",
    "C08L 9/06",
    "C08C 19/00",
    "C08C 19/22",
    "C08C 19/25",
    "C08C 19/44",
    "C08K 3/013"
  ],
  "assignees": [
    "Yokohama Rubber Co Ltd"
  ],
  "inventors": [
    "Kazuya Uenishi",
    "Makoto Ashiura",
    "Motoji Fujita",
    "Naoya Amino",
    "Satoshi Mihara",
    "Yu Shinke"
  ],
  "filing_date": "2017-02-10",
  "publication_date": "2021-05-18",
  "grant_date": "2021-05-18",
  "priority_date": "2016-02-23",
  "application_number": "US-201716078276-A",
  "family_id": "59740559",
  "cited_by_count": 1,
  "citations": [
    "JPS5465788A",
    "JPH0260907A",
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    "JPH10306114A",
    "US6103842A",
    "JP2002520457A",
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    "JP2006188682A",
    "US7291687B1",
    "JP2009263587A",
    "US20110319519A1",
    "JP2011084634A",
    "WO2011049180A1",
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    "JP2013231177A",
    "US20180051101A1"
  ]
}