POLYTETRAFLUOROETHYLENE AQUEOUS DISPERSION
    3.
    发明申请

    公开(公告)号:US20200056031A1

    公开(公告)日:2020-02-20

    申请号:US16661064

    申请日:2019-10-23

    摘要: To provide a PTFE aqueous dispersion which is excellent in mechanical stability, while being not susceptible to foaming. A polytetrafluoroethylene aqueous dispersion which is characterized by containing from 15 to 70 mass % of PTFE particles having an average primary particle diameter of from 0.1 to 0.5 μm; from 0.1 to 20,000 ppm, to the PTFE particles, of a fluorinated emulsifier selected from a C4-7 fluorinated carboxylic acid which may have an etheric oxygen atom, and salts of thereof; from 1 to 20 parts by mass, to 100 parts by mass of the PTFE particles, of a nonionic surfactant represented by R1—O-A-H (wherein R1 is a C8-18 alkyl group, and A is a polyoxyalkylene chain); from 0.004 to 0.040 parts by mass, to 100 parts by mass of the PTFE particles, of a polyether polysiloxane copolymer, wherein the polyether chain consists solely of a polyoxypropylene group; and water.

    Polytetrafluoroethylene aqueous dispersion

    公开(公告)号:US11104787B2

    公开(公告)日:2021-08-31

    申请号:US16661064

    申请日:2019-10-23

    摘要: To provide a PTFE aqueous dispersion which is excellent in mechanical stability, while being not susceptible to foaming. A polytetrafluoroethylene aqueous dispersion which is characterized by containing from 15 to 70 mass % of PTFE particles having an average primary particle diameter of from 0.1 to 0.5 μm; from 0.1 to 20,000 ppm, to the PTFE particles, of a fluorinated emulsifier selected from a C4-7 fluorinated carboxylic acid which may have an etheric oxygen atom, and salts of thereof; from 1 to 20 parts by mass, to 100 parts by mass of the PTFE particles, of a nonionic surfactant represented by R1—O-A-H (wherein R1 is a C8-18 alkyl group, and A is a polyoxyalkylene chain); from 0.004 to 0.040 parts by mass, to 100 parts by mass of the PTFE particles, of a polyether polysiloxane copolymer, wherein the polyether chain consists solely of a polyoxypropylene group; and water.

    METHOD FOR PRODUCING TETRAFLUOROETHYLENE COPOLYMER AQUEOUS DISPERSION

    公开(公告)号:US20180298131A1

    公开(公告)日:2018-10-18

    申请号:US15977326

    申请日:2018-05-11

    IPC分类号: C08F214/26 C08J3/07

    摘要: To provide a method for producing a tetrafluoroethylene copolymer-containing aqueous dispersion excellent in stability against a mechanical stress. The method for producing an aqueous dispersion containing a tetrafluoroethylene copolymer is characterized by comprising a polymerization step of subjecting tetrafluoroethylene (TFE) and a (perfluoroalkyl) ethylene to a polymerization reaction in an aqueous medium using a polymerization initiator in the presence of a fluorinated emulsifier, to obtain an aqueous emulsion having a solid content concentration of from 10 to 45 mass %, and a concentrating step of adding a nonionic surfactant represented by R1—O-A-H (R1 is a C8-18 alkyl group, and A is a polyoxyalkylene chain) to the aqueous emulsion, followed by concentration to a solid content concentration of from 50 to 70% to obtain an aqueous dispersion, wherein in the polymerization step, TFE is continuously or intermittently supplied to the polymerization reaction vessel, and a chain transfer agent is added at the time when from 10 to 95 mass % of the total mass of TFE to be used in the polymerization reaction has been supplied.