US 11,952,441 B2
Polytetrafluoroethylene production method
Taketo Kato, Osaka (JP); Yohei Fujimoto, Osaka (JP); Kenji Ichikawa, Osaka (JP); Hiroyuki Sato, Osaka (JP); Yoshinori Nanba, Osaka (JP); Hirotoshi Yoshida, Osaka (JP); Kengo Ito, Osaka (JP); Chiaki Okui, Osaka (JP); Masamichi Sukegawa, Osaka (JP); and Taku Yamanaka, Osaka (JP)
Assigned to DAIKIN INDUSTRIES, LTD., Osaka (JP)
Appl. No. 17/280,940
Filed by DAIKIN INDUSTRIES, LTD., Osaka (JP)
PCT Filed Oct. 3, 2019, PCT No. PCT/JP2019/039188
§ 371(c)(1), (2) Date Mar. 29, 2021,
PCT Pub. No. WO2020/071504, PCT Pub. Date Apr. 9, 2020.
Claims priority of application No. 2018-188700 (JP), filed on Oct. 3, 2018.
Prior Publication US 2021/0355254 A1, Nov. 18, 2021
Int. Cl. C08F 114/26 (2006.01); C08L 27/18 (2006.01)
CPC C08F 114/26 (2013.01) [C08L 27/18 (2013.01)] 12 Claims
 
1. A method for producing polytetrafluoroethylene comprising:
polymerization of tetrafluoroethylene in an aqueous medium in the presence of a nucleating agent and a hydrocarbon anionic surfactant to obtain polytetrafluoroethylene particles,
wherein a total amount of the nucleating agent and the hydrocarbon anionic surfactant at the initiation of polymerization is 60 ppm or more based on the aqueous medium, and
wherein the nucleating agent is at least one selected from the group consisting of a fluoropolyether and a nonionic surfactant.