公开(公告)号：US20240150505A1

公开(公告)日：2024-05-09

申请号：US18397595

申请日：2023-12-27

Applicant: DAIKIN INDUSTRIES, LTD.

Inventor： Takahiro TAIRA ,  Kazuhiro Mishima ,  Takayuki Tanaka ,  Takeki Kusunoki ,  Masayoshi Miyamoto ,  Tomoki Minamiyama ,  Mitsuo Tsukamoto ,  Kenji Ichikawa ,  Takuya Yamabe ,  Hirotoshi Yoshida ,  Taketo Kato ,  Taku Yamanaka

IPC: C08F214/26 ,  B29C43/00 ,  C08F2/18 ,  C08F6/24 ,  C08F8/22

CPC classification number: C08F214/262 ,  B29C43/003 ,  B29C43/006 ,  C08F2/18 ,  C08F6/24 ,  C08F8/22 ,  B29K2027/18

Abstract: A method for producing a polytetrafluoroethylene powder, which includes subjecting tetrafluoroethylene to suspension polymerization in an aqueous medium to prepare a suspension-polymerized particle of non melt-processible polytetrafluoroethylene, drying the suspension-polymerized particle to prepare a dry particle, subjecting the dry particle to fluorine radical treatment to prepare a fluorine radical-treated particle, and crushing the fluorine radical-treated particle to produce a polytetrafluoroethylene powder. Also disclosed is a polytetrafluoroethylene formed article obtained by forming the polytetrafluoroethylene powder, as well as a polytetrafluoroethylene compression-molded article obtained by compression molding the polytetrafluoroethylene powder.

公开(公告)号：US11780973B2

公开(公告)日：2023-10-10

申请号：US17259859

申请日：2019-07-12

Applicant: OSAKA UNIVERSITY ,  DAIKIN INDUSTRIES, LTD.

Inventor： Akihiro Oshima ,  Takayuki Tanaka ,  Hideki Nakaya ,  Kazuyuki Satoh ,  Ryosuke Senba

IPC: C08J3/28 ,  C08F8/50 ,  C08F114/26

CPC classification number: C08J3/28 ,  C08F8/50 ,  C08F114/26 ,  C08J2327/18

Abstract: Provided is a method for producing low-molecular-weight polytetrafluoroethylene which is less likely to generate C6-C14 perfluorocarboxylic acids and salts thereof. The disclosure relates to a method for producing low-molecular-weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×102 to 7.0×105 Pa·s. The method includes (1) irradiating high-molecular-weight polytetrafluoroethylene with radiation in a substantially oxygen-free state and decomposing the high-molecular-weight polytetrafluoroethylene into a low-molecular-weight component and (2) deactivating, in a substantially oxygen-free state, at least part of main-chain radicals and end radicals generated by the irradiation and providing the low-molecular-weight polytetrafluoroethylene.

公开(公告)号：US20220356276A1

公开(公告)日：2022-11-10

申请号：US17865049

申请日：2022-07-14

Applicant: DAIKIN INDUSTRIES, LTD. ,  OSAKA UNIVERSITY

Inventor： Takayuki Tanaka ,  Kazuyuki Satoh ,  Akihiro Oshima

IPC: C08F14/26 ,  C08F2/50

Abstract: A method for producing low molecular weight polytetrafluoroethylene having a melt viscosity at 380° C. of 1.0×102 to 7.0×105 Pa·s. The method includes: (1) irradiating high molecular weight polytetrafluoroethylene with radiation in the presence of a substance capable of generating a free hydrogen atom and decomposing the high molecular weight polytetrafluoroethylene into a low molecular weight component; and (2) deactivating at least part of main-chain radicals and end radicals generated by the irradiation and providing the low molecular weight polytetrafluoroethylene. Also disclosed is a composition containing the low molecular weight polytetrafluoroethylene and a low molecular weight polytetrafluoroethylene.

公开(公告)号：US11518826B2

公开(公告)日：2022-12-06

申请号：US16957288

申请日：2018-12-25

Applicant: DAIKIN INDUSTRIES, LTD.

Inventor： Kazuhiro Mishima ,  Takahiro Taira ,  Chiaki Okui ,  Takayuki Tanaka ,  Masayoshi Miyamoto ,  Taku Yamanaka

IPC: C08F2/46 ,  C08F2/50 ,  C08G61/04 ,  C08F14/26 ,  C08J3/16 ,  C08J3/28

Abstract: A method for producing a polytetrafluoroethylene powder, which includes applying an ultrasonic wave to a polytetrafluoroethylene aqueous dispersion containing polytetrafluoroethylene particles to coagulate the polytetrafluoroethylene particles.