STARCH COMPOSITION
    2.
    发明申请

    公开(公告)号:US20220089842A1

    公开(公告)日:2022-03-24

    申请号:US17429140

    申请日:2020-02-06

    申请人: KEMIRA OYJ

    发明人: Asko KARPPI

    摘要: The present invention relates to an aqueous composition of dissolved starch, use of it and compositions comprising the same. The composition has good handling properties and viscosity stability also in elevated starch concentrations.

    METHOD FOR MANUFACTURING MULTI-LAYERED FIBROUS WEB AND MULTI-LAYERED FIBROUS WEB

    公开(公告)号:US20210262169A1

    公开(公告)日:2021-08-26

    申请号:US17252295

    申请日:2019-07-10

    申请人: Kemira Oyj

    摘要: A method for manufacturing a multi-layered fibrous web is disclosed, which includes at least two fibrous layers, where each layer is formed from one or more fibre stocks. The fibrous layers are combined prior to subjecting the multilayered fibrous web to wet-pressing and drying. At least one layer of the multi-layered fibrous web is formed from a fibre stock including at least 50 weight-% of a chemi-thermomechanical pulp (CTMP), a hardwood kraft pulp and/or a recycled fibre material calculated from a thick stock applied to a particular layer approach system. A first strength component and a second strength component are added to the fibre stock. The first strength component includes a cationic strength agent and the second strength component includes a synthetic amphoteric polymer composition having a net charge from −3 to +1 meq/g (dry), at a pH of 7.

    METHOD FOR ON-SITE GLYOXYLATION OF POLYACRYLAMIDE

    公开(公告)号:US20240360253A1

    公开(公告)日:2024-10-31

    申请号:US18688022

    申请日:2022-09-21

    申请人: KEMIRA OYJ

    IPC分类号: C08F8/28 D21H17/45 D21H21/18

    摘要: Method for on-site glyoxylation of polyacrylamide in paper mill, board mill or the like is disclosed. Discontinuous batch glyoxylation reaction of aqueous reaction mixture is performed. The method comprises forming or obtaining the aqueous reaction mixture having a start viscosity and comprising polyacrylamide base polymer having weight average molecular weight of 30 000-300 000 g/mol and glyoxal. Concentration of the polyacrylamide base polymer in the reaction mixture is 1.5-8% above a Critical Concentration of the polyacrylamide base polymer. A feed of an alkali is added to the reaction mixture while measuring viscosity of the reaction mixture and/or a process variable related to the viscosity of the reaction mixture and the on-site glyoxylation reaction of polyacrylamide base polymer in the reaction mixture is allowed to proceed. When a predetermined end viscosity value is attained the feed of alkali is ended and acid is added to the reaction mixture.

    POLYACRYLAMIDE COMPOSITION AND ITS USE

    公开(公告)号:US20230140443A1

    公开(公告)日:2023-05-04

    申请号:US17906358

    申请日:2021-03-17

    申请人: KEMIRA OYJ

    IPC分类号: C08L33/26 C08K5/07

    摘要: An aqueous prepolymer composition, which comprises a polyacrylamide base polymer comprising 10 - 40 mol-% of cationic monomers and having a weight average molecular weight Mw in the range of 120 000 - 350 000 g/mol, 0.1 - 1 weight-% of glyoxal, calculated from the total weight of the aqueous prepolymer composition, and a buffering acid for adjusting pH of the composition in the range of 2 - 4. A prepolymer composition is used in a method for producing on-site glyoxylated polyacrylamide useful in paper or board manufacturing.