Asahi Glass Company, Limited

Agc Inc.

Agc Chemicals Europe, Limited

Masahiro Takazawa

Shinya Higuchi

Shigeki Kobayashi

Shigeru Aida

Akiko Tanaka

Takehiro Kose

Hiroki Nagai

Ariana Claudia Morgovan-Ene

Anthony Eugene Wade

Diane Caine

A modified polytetrafluoroethylene which can be formed under a low extrusion pressure and with which changes of the extrusion pressure are suppressed, even in paste extrusion at a high RR ratio, and its production method. The modified polytetrafluoroethylene having units based on tetrafluoroethylene, 0.020 to 0.040 mass % of units based on a monomer represented by the following formula (1), and 0.003 to 0.080 mass % of units based on a monomer represented by the following formula (2), each based on all units of the modified polytetrafluoroethylene. The monomers of formulae (1) and (2) are represented by: CH&#x2550;CH&#x2014;CF(1), wherein n is from 2 to 6; and CF&#x2550;CFO(LO)Rf (2), wherein L is a perfluoroalkylene group, Rf is a perfluoroalkyl group, and m is an integer of from 0 to 4.

Modified polytetrafluoroethylene and method for producing same

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 &#x3bc;m; from 0.1 to 20,000 ppm, to the PTFE particles, of a fluorinated emulsifier selected from a Cfluorinated 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 R&#x2014;O-A-H (wherein Ris a Calkyl 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

To provide a method for recovering an acid of an anionic fluorinated emulsifier with a high yield from a basic ion exchange resin having a nonionic surfactant physically adsorbed thereon and having the anionic fluorinated emulsifier adsorbed thereon. A method for eluting and recovering an acid of an anionic fluorinated emulsifier from a basic ion exchange resin having a nonionic surfactant physically adsorbed thereon and having the anionic fluorinated emulsifier adsorbed thereon, which comprises a step (1) of bringing the basic ion exchange resin into contact with a water-soluble organic solvent and a step (2) of recovering the acid of the anionic fluorinated emulsifier from the basic ion exchange resin from which the ionic surfactant is eluted in the step (1).

Method for recovering anionic fluorinated emulsifier

To provide a process for producing a PTFE molding powder having a high bulk density from granular polymer particles without using an emulsifying agent having problems of bioaccumulation and toxicity. A process for producing a polytetrafluoroethylene molding powder, which comprises a step of suspension-polymerizing a monomer containing at least 99.8 mass % of tetrafluoroethylene in an aqueous medium to produce granular polymer particles and a step of milling the granular polymer particles, wherein the aqueous medium contains a compound represented by R(OCF(X)CF)OCF(X)COOM, at a concentration of from 0.5 to 2,000 ppm. Ris a perfluorinated Cmonovalent organic group, Xand Xare fluorine atoms, etc., and Mis an ammonium ion or the like.

Process for producing polytetrafluoroethylene molding powder and process for producing polytetrafluoroethylene agglomerated product

Growing community of inventors

Chiyoda-ku, Japan

Masahiro Takazawa