公开(公告)号：US11111319B2

公开(公告)日：2021-09-07

申请号：US16089441

申请日：2017-03-30

Applicant: KURARAY CO., LTD.

Inventor： Yusuke Amano ,  Takumi Takayama ,  Kazuhiko Maekawa

IPC: C08F16/06 ,  C08F116/06

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)

公开(公告)号：US10766978B2

公开(公告)日：2020-09-08

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 ,  C08F6/08 ,  B01J31/22 ,  C08F8/12 ,  C08K5/23

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：US11261270B2

公开(公告)日：2022-03-01

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 ,  C08F2/38 ,  C08F8/12

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：US09943825B2

公开(公告)日：2018-04-17

申请号：US14692986

申请日：2015-04-22

Applicant: KURARAY CO., LTD.

Inventor： Keisuke Morikawa ,  Yusuke Amano ,  Naoyuki Iwachido ,  Naoki Fujiwara ,  Takumi Takayama

IPC: B01J20/00 ,  B32B5/16 ,  B01J20/26 ,  B01D15/00 ,  B01J20/30 ,  C08F255/02 ,  C08J9/26 ,  C22B3/24 ,  B01J20/34 ,  B01J20/32 ,  B01J20/28 ,  B01J39/18 ,  C08F261/04 ,  C08J3/12 ,  C08F271/02 ,  C08F8/32 ,  C02F1/28 ,  C02F101/20 ,  C02F101/22

CPC classification number: B01J20/264 ,  B01D15/00 ,  B01J20/28004 ,  B01J20/28016 ,  B01J20/28083 ,  B01J20/28085 ,  B01J20/30 ,  B01J20/3014 ,  B01J20/3028 ,  B01J20/3071 ,  B01J20/3078 ,  B01J20/3085 ,  B01J20/321 ,  B01J20/3212 ,  B01J20/3219 ,  B01J20/3272 ,  B01J20/3278 ,  B01J20/3293 ,  B01J20/3425 ,  B01J20/3475 ,  B01J39/18 ,  C02F1/285 ,  C02F2101/20 ,  C02F2101/22 ,  C08F8/32 ,  C08F255/02 ,  C08F261/04 ,  C08F271/02 ,  C08J3/12 ,  C08J9/26 ,  C08J2201/046 ,  C08J2323/08 ,  C08J2329/04 ,  C08J2351/06 ,  C08J2429/04 ,  C08J2451/06 ,  C22B3/24 ,  Y02P10/234 ,  Y10T428/2982 ,  C08F220/32 ,  C08F220/28 ,  C08F220/54

Abstract: Provided are graft copolymer particles enabling introduction of adsorptive functional groups adsorbing metals and others, a method for producing same, and an adsorbent using same. (1) Porous graft copolymer particles containing graft chains introduced into porous particles (particle surface having an average pore diameter of 0.01-50 μm) including at least one resin selected from olefin resins, water-insoluble modified polyvinyl alcohol resins, amide resins, cellulosic resins, chitosan resins and (meth)acrylate resins. (2) A method for producing porous graft copolymer particles including (I) melt-kneading a polymer A and a polymer B other than the polymer A to obtain a compound material, (II) extracting and removing the polymer B from the compound material to obtain a porous material of the polymer A, (III) granulating the porous material, and (IV) introducing graft chains into the porous particles. (3) An adsorbent of porous graft copolymer particles.