公开(公告)号：US20220144977A1

公开(公告)日：2022-05-12

申请号：US17438697

申请日：2020-03-12

Applicant: KURARAY CO., LTD.

Inventor： Yuki TACHIBANA ,  Yusuke AMANO ,  Yuki SHIMIZU ,  Kazuhiko MAEKAWA

IPC: C08F8/14 ,  B29B9/12 ,  C08F16/06

Abstract: A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units from 95 to 99.99 mol %, and having an average particle diameter from 50 to 2000 μm. The production method does not cause the problem of the residual sulfur content derived from a liquid medium used for reaction and is also capable of modifying the vinyl alcohol-based polymer particles while maintaining the particle shape.

公开(公告)号：US20220089793A1

公开(公告)日：2022-03-24

申请号：US17418468

申请日：2019-12-26

Applicant: KURARAY CO., LTD.

Inventor： Yuki TACHIBANA ,  Yusuke AMANO ,  Yuki SHIMIZU ,  Kazuhiko MAEKAWA

IPC: C08F16/06 ,  C08J7/16

Abstract: A method of producing modified vinyl alcohol-based polymer particles, includes mixing vinyl alcohol-based polymer particles with a mixed medium containing unsaturated carboxylic acid, an acid catalyst, and water, wherein, by mixing the vinyl alcohol-based polymer particles with the mixed medium, the vinyl alcohol-based polymer particles are reacted with the unsaturated carboxylic acid to obtain modified vinyl alcohol-based polymer particles containing a vinyl ester unit represented by a formula (2) below, having a vinyl alcohol unit content based on the total constitutional units of 60 mol % or more and less than 95 mol %, and having an average particle diameter from 50 to 2000 μm. The production method is capable of controlling the particle shape and does not cause the problem of the residual sulfur content, and is further convenient and economically advantageous.

公开(公告)号：US20230226520A1

公开(公告)日：2023-07-20

申请号：US18000970

申请日：2021-06-07

Applicant: KURARAY CO., LTD.

Inventor： Takumi TAKAYAMA ,  Kazuhiko MAEKAWA ,  Kazutoshi MISHIMA

IPC: B01J20/26 ,  C08F297/02 ,  B01J20/28 ,  A61L15/24 ,  A23L3/3517

CPC classification number: B01J20/264 ,  C08F297/026 ,  B01J20/28016 ,  A61L15/24 ,  A23L3/3517 ,  A01K1/0155

Abstract: A block copolymer (A) including a vinyl alcohol-based polymer block (b) and an ionic polymer block (c) containing a monomer unit with an ionic group forming a salt and a vinyl alcohol-based monomer unit. The ionic group is a carboxylic acid group, a sulfonic acid group, or an ammonium group. The vinyl alcohol-based polymer block (b) has a number-average molecular weight (Mnb) from 15,000 to 220,000. The ionic polymer block (c) has a content of the vinyl alcohol-based monomer unit from 5 to 95 mol % based on the total monomer units. The block copolymer (A) has a number-average molecular weight (MnA) from 20,000 to 440,000. A ratio (Mnb/MnA) of the number-average molecular weight (Mnb) to the number-average molecular weight (MnA) is from 0.1 to 0.9.

公开(公告)号：US20240174785A1

公开(公告)日：2024-05-30

申请号：US18548377

申请日：2022-03-10

Applicant: KURARAY CO., LTD.

Inventor： Takumi TAKAYAMA ,  Hinako TSUCHIYA ,  Kazuhiko MAEKAWA

IPC: C08F293/00

CPC classification number: C08F293/00

Abstract: A method of producing a polymer including a polymerization step of obtaining a polymer by controlled radical polymerization of a monomer (Y) in the presence of an organic compound (A) represented by formula (I) and its constituents and a radical generator (B), where a molar ratio (B/A) of (B) to (A) is from 0.5 to 20. The production method allows synthesis of a highly safe polymer with a high molecular weight while precisely controlling the molecular sequence and the end structure. In addition, the production method is low in toxicity, environmentally friendly, and operated at low costs.

公开(公告)号：US20220267499A1

公开(公告)日：2022-08-25

申请号：US17623105

申请日：2020-06-25

Applicant: KURARAY CO., LTD.

Inventor： Takumi TAKAYAMA ,  Kazutoshi MISHIMA ,  Hiroyuki KONISHI ,  Kazuhiko MAEKAWA

IPC: C08F293/00 ,  C08F4/70 ,  C08L53/00

Abstract: Disclosed is a vinyl alcohol-based block copolymer that is a block copolymer composed of a vinyl alcohol-based polymer block (B-b) and a copolymer block (B-c) comprising a vinyl alcohol-based monomer unit and an acrylic acid-based monomer unit, wherein a content (Z) of the acrylic acid-based monomer unit relative to all monomer units is 0.05 to 20.0 mol %, the block copolymer has a saponification degree of 80 to 99.99 mol %, the block copolymer has a number-average molecular weight (Mna) of 20,000 to 440,000, the block copolymer has a molecular weight distribution (Mwa/Mna) of 1.05 to 1.95, and a ratio (DPb/DPa) of a number-average polymerization degree (DPb) of the vinyl alcohol-based polymer block (B-b) to the number-average polymerization degree (DPa) of the block copolymer is 0.010 to 0.999. The copolymer has a fine balance derived from the copolymer block (B-c) of having a superior solubility in water while being unlikely to undergo thickening or gelation due to pH fluctuation, and also has high mechanic strength derived from the vinyl alcohol-based polymer block (B-b).

公开(公告)号：US20220220332A1

公开(公告)日：2022-07-14

申请号：US17605849

申请日：2020-04-24

Applicant: Kuraray Co., Ltd

Inventor： Yuki TACHIBANA ,  Yusuke AMANO ,  Kazuhiko MAEKAWA

IPC: C09D129/04 ,  C08F16/06 ,  C08K3/36 ,  C08K3/34 ,  C09D7/61 ,  C09D7/65 ,  C09D5/14 ,  B65D65/42

Abstract: A coating composition may include a modified polyvinyl alcohol resin (A) having an ethylene unsaturated group in a side chain thereof. Examples of the modified polyvinyl alcohol resin (A) include those including a structural unit represented by formula (II) or (III). Substrates in various technical fields such as the resin molding field, automobile/railway/aircraft/ships-related field, medical product field, food field, agriculture/gardening field, electrical field, and construction field can be coated with such a coating composition.

公开(公告)号：US20210246299A1

公开(公告)日：2021-08-12

申请号：US16972849

申请日：2019-06-07

Applicant: KURARAY CO., LTD.

Inventor： Yusuke AMANO ,  Eiichi ISHIDA ,  Kazuhiko MAEKAWA ,  Daisuke KODA ,  Hiroshi KANBARA

IPC: C08L51/04 ,  C08L51/06 ,  C08L29/04 ,  C08L23/08 ,  C08L23/22 ,  C08F236/06 ,  C08F236/08 ,  C08K3/04 ,  C08K3/36 ,  C08K5/54 ,  C08L9/06 ,  C08L7/00 ,  C08L91/00 ,  B60C1/00

Abstract: The present invention provides a rubber composition having superior moldability, wear resistance, and grip performance, and tires therewith. The present invention relates to a rubber composition comprising: a copolymer (B) constituted of a vinyl alcohol polymer (B-1) region and a diene polymer (B-2) region; and a rubber component (C), wherein the rubber composition comprises 1 to 20 parts by mass of the copolymer (B) relative to 100 parts by mass of the rubber component (C).

公开(公告)号：US20200216584A1

公开(公告)日：2020-07-09

申请号：US16630282

申请日：2018-07-11

Applicant: KURARAY CO., LTD. ,  UNIVERSITE DE LIEGE

Inventor： Takumi TAKAYAMA ,  Kazuhiko MAEKAWA ,  Christophe DETREMBLEUR ,  Antoine DEBUIGNE ,  Christine JEROME

IPC: C08F16/06 ,  C08F8/12 ,  C08F2/38

Abstract: A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw/Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, wherein the polyvinyl alcohol contains an end group represented by a formula (I) below, and a molar ratio (X) of the end group based on total monomer units and the number-average molecular weight (Mn) satisfy a formula (1) below. Such a polyvinyl alcohol has a narrow molecular weight distribution and a high number-average molecular weight with hue good. (In the formula, R1 denotes an optionally substituted aromatic group having a carbon number from 6 to 20, and R2 denotes a hydrogen atom, an alkyl group having a carbon number from 1 to 20, or an optionally substituted aromatic group having a carbon number from 6 to 20.) X·Mn/44≥0.5  (1)

公开(公告)号：US20190119414A1

公开(公告)日：2019-04-25

申请号：US16089483

申请日：2017-03-30

Applicant: KURARAY CO., LTD. ,  UNIVERSITE DE LIEGE

Inventor： Takumi TAKAYAMA ,  Yusuke AMANO ,  Kazuhiko MAEKAWA ,  Christophe DETREMBLEUR ,  Antoine DEBUIGNE ,  Christine JEROME

IPC: C08F16/06 ,  C08F18/08 ,  C08F8/12 ,  B01J31/22

Abstract: A polyvinyl alcohol is produced in a method comprising: a polymerization step comprising polymerizing vinyl ester monomers by controlled radical polymerization in the presence of a radical initiator and an organic cobalt complex to obtain a polymer solution containing a polyvinyl ester; an extraction step comprising extracting a cobalt complex from the polymer solution by contacting an aqueous solution containing a water-soluble ligand with the polymer solution; and a saponification step comprising saponifying the polyvinyl ester after the extraction step to obtain a polyvinyl alcohol. A method for producing a polyvinyl alcohol is thus provided that has a narrow molecular weight distribution and a high number-average molecular weight with good hue and further good solubility in water.

公开(公告)号：US20190100607A1

公开(公告)日：2019-04-04

申请号：US16089441

申请日：2017-03-30

Applicant: KURARAY CO., LTD.

Inventor： Yusuke AMANO ,  Takumi TAKAYAMA ,  Kazuhiko MAEKAWA ,  Kazuhiko MAEKAWA

IPC: C08F16/06

Abstract: A polyvinyl alcohol has a number-average molecular weight (Mn) from 4,400 to 440,000, a molecular weight distribution (Mw/Mn) from 1.05 to 1.70, a degree of saponification from 80 to 99.99 mol %, and a carbon-carbon double bond content (X) of 0.1 mol % or less based on total monomer units, and satisfying a formula (1) below. A polyvinyl alcohol, having a narrow molecular weight distribution and a high number-average molecular weight with good hue, and a method for producing the same are thus provided. X·Mn≤1000  (1)