Sharp Kabushiki Kaisha Corporation

Japan Atomic Energy Research Institute

Japan Atomic Energy Agency

Nitto-denko Corporation

Other

Toyota Jidosha Kabushiki Kaisha

Mitsubishi Gas Chemical Company, Inc.

Takeda Chemical Industries, Inc.

Gesellschaft Fur Schwerionenforschung Mbh

Takeda Chemical Indus., Ltd.

Keizo Shida

Masaru Yoshida

Shigeo Nakajima

Masaharu Asano

Isao Kaetsu

Koichi Tanaka

Akiyoshi Mikami

Takashi Ogura

Yoshikazu Yoshimoto

Kouji Taniguchi

Hiroshi Wada

Takuo Yamashita

Kousuke Terada

Tetsuya Yamaki

Hiroaki Nakaya

Tomonari Suzuki

Yozo Nagai

Toshimitsu Tachibana

Minoru Kumakura

Soji Nishiyama

Katsushi Okibayashi

Jinhua Chen

Yasunari Maekawa

Satoshi Yamaue

Hiroshi Morimoto

Akihiko Ito

Hidetoshi Yamanaka

Katsuyuki Nakai

Masahiro Adachi

Yasuyoshi Kaise

Hideaki Tanaka

Shoei Kataoka

Yoshimitsu Tajima

Koji Taniguchi

Motoo Mohri

Hiroshi Okubo

Shigeharu Takagi

Yousuke Morita

Yosuke Morita

Toshiya Saito

Nobuhiro Yanagisawa

Michiyo Kasahara

Misaki Kobayashi

Akira Shiraishi

Yoshiaki Nakase

Yoshihiro Izumi

Yutaka Ishii

Yoshitaka Yamamoto

Yozo Narutaki

Mitsuhiro Koden

Tomohiko Yamamoto

Naofumi Kimura

Sayuri Fujiwara

Masataka Matsuura

Kazuhiro Emoto

Akitsugu Hatano

Takayoshi Yamaguchi

Yasunori Shimada

Mitsuhiko Yoshikawa

Yoshimi Kojima

Goro Shimaoka

Keiichi Uno

Yuri Evgenievich Korchev

Eizo Ohno

Koichiro Hayashi

Yukihiko Nakata

Mikio Takeda

Yoshinobu Kakihara

Tadashi Iwai

Masanobu Urabe

Hisako Yuasa

Koji Ianiguchi

Yoshiki Murakami

Reimar Spohr

Yu Pavel Apel

Zuzanna Siwy

Tadafumi Yamauchi

A vinyl monomer is graft polymerized on an aromatic hydrocarbon-based polymer film substrate to introduce graft chains into the substrate and thereafter a functional monomer represented by the following formula and having sulfonic acid groups or functional groups capable of conversion to sulfonic acid groups is graft polymerized to introduce the sulfonic acid groups or the functional groups capable of conversion to sulfonic acid groups: where R is an aromatic ring or an aliphatic chain; X is (1) &#x2014;OH, (2) &#x2014;OLi, &#x2014;ONa or &#x2014;OK, (3) &#x2014;F or &#x2014;Cl, or (4) &#x2014;OCHwhere n is an integer of 1 to 7. Since the graft chains obtained by graft polymerization of the vinyl monomer can also be utilized as scaffold polymers, the graft polymerizability of the functional monomer to the aromatic hydrocarbon-based polymer film substrate is sufficiently improved to enable the preparation of a polymer electrolyte membrane that excels not only in proton conductivity and mechanical strength but also in dimensional stability.

Highly proton-conductive polymer electrolyte membranes that excel in mechanical strength and a process for producing the same

A functional membrane and a production method thereof including: an ion irradiation step in which a polymer film substrate is irradiated with high energy heavy ions at 10to 10ions/cm, to generate active species in the film substrate; and a graft polymerization step in which after the ion irradiation step, the film substrate is added with one or more monomers selected from a group A consisting of monomers each having a functional group and 1 to 80 mol % of a monomer including a group B consisting of a crosslinking agent(s) for the group A monomer(s), and the film substrate and the monomer(s) are graft-polymerized. There is obtained a functional membrane having high functionality in conjunction with the gas barrier property intrinsically possessed by a polymer film substrate, in particular, a polymer electrolyte membrane optimal as a polymer electrolyte membrane for use in fuel cells, high in proton conductivity and excellent in gas barrier property.

Functional membrane and production method thereof, and electrolyte membrane for use in fuel cell and production method thereof

An object is to provide an electrolyte membrane that maintains excellent cell characteristics for a long time under high temperature and low water retention, as this is the most important point in fuel cells. A process for producing a polymer electrolyte membrane for fuel cells is provided, which process comprises in sequence: forming graft molecular chains by graft-polymerization of a vinyl silane coupling agent on a polymer film substrate that has phenyl groups capable of holding sulfonic acid groups; introducing sulfonic acid groups into phenyl groups contained in the graft molecular chains; and hydrolyzing and condensing alkoxy groups contained in the graft molecular chains so that a silane crosslinked structure is introduced between the graft molecular chains. A polymer electrolyte membrane produced by the process is also provided.

Silane crosslinked structure-introduced fuel-cell polymer electrolyte membrane and fuel-cell electrode assembly having the same

Polymer ion-exchange membranes having outstanding electrical conductivity, water retention and oxidation resistance are produced by the steps of uniformly mixing an organic high-molecular weight resin with functional inorganics having the abilities to promote graft polymerization of polymerizable monomers, adsorb water and conduct protons, irradiating the resulting functional inorganics/polymer membrane to initiate graft polymerization or graft copolymerization of polymerizable monomers having functional groups, and then introducing sulfonic acid groups into the graft chains.

Process or producing hybrid ion-exchange membranes comprising functional inorganics and graft polymer and electrolyte membranes for use in fuel cells comprising the hybrid ion-exchange membranes

A polymer film substrate is irradiated with ions to make a large number of nano-sized through-holes and the substrate may be further irradiated with ionizing radiation so that a functional monomer may be grafted or co-grafted onto a surface of the film and within the holes; in addition, sulfonic acid group(s) may be introduced into the graft chains to produce a polymer ion-exchange membrane that may have high oxidation resistance, dimensional stability, electrical conductivity and/or methanol resistance, as well as may have an ion-exchange capacity controlled over a wide range.

Processes for producing nano-space controlled polymer ion-exchange membranes

A functional membrane is provided, which has high functionality combined with the gas barrier performance and mechanical strength inherent in a polymer film substrate. In particular, a polymer electrolyte membrane is provided, which is excellent in terms of high proton conductivity and gas barrier performance and is most appropriate to serve as a polymer electrolyte membrane for fuel cells. A method for producing a functional membrane is provided, which comprises: a step of ion irradiation, in which active species are generated in a polymer film substrate containing nonconductive inorganic particles by irradiating the polymer film substrate with high-energy heavy ions to the extent of 104/cm2 to 1014/cm2; and a step of graft polymerization subsequent to the step of ion irradiation, in which one or more monomers selected from group A consisting of monomers containing useful functional groups are added such that the monomers are graft polymerized with the polymer film substrate.

Functional membrane and electrolyte membrane for fuel cells and method for producing the same

A crosslinked nano-inorganic particle/polymer electrolyte membrane composed of a polymer film substrate, graft molecular chains bound to the backbone skeleton of the polymer film substrate and comprising a vinyl monomer graft-polymerized, sulfonic groups bound to the graft molecular chains, and an inorganic material as nano-scale particles uniformly dispersed within a crosslinked structure ascribed to the backbone skeleton of the polymer film substrate and the graft molecular chains, wherein the backbone skeleton of the polymer film substrate, the graft molecular chains, and the nano-inorganic particles mutually construct a crosslinked structure.

Crosslinked nano-inorganic particle/polymer electrolyte membrane for membrane electrode assembly

By performing photograft polymerization of functional monomers such that grafted chains will be introduced from the surface of a polymer base film into its interior without deteriorating its inherent characteristics and also by creating a multiplex crosslinked structure between the grafted chains and the base film under such conditions as to cause preferential radiation-induced crosslinking reaction, there is produced a polymer electrolyte membrane having high enough oxidation resistance and proton conductivity to be suitable for use in fuel cells.

Process for producing polymer electrolyte membranes for fuel cells, polymer electrolyte membranes for fuel cells produced by the process, and fuel cell membrane-electrode assemblies using the membranes

A method for producing a polymer electrolyte membrane for electrolyte fuel cells includes: irradiating gamma rays onto a polymer substrate to obtain a crosslinked polytetrafluoroetylene substrate, grafting a styrenic monomer and bis(vinylphenyl)ethane as monomers to the crosslinked polymer substrate, and introducing sulfonic acid groups into graft side chains formed by grafting. Fluoro polymer substrates such as polytetrafluoroethylene and ethylene tetrafluoroethylene copolymer may be used.

Methods for producing a polymer electrolyte membrane having improved oxidation resistance

The objective of the invention is to solve the problems of conventional polymer electrolyte membranes, including small ion-exchange capacity and low oxidation and methanol resistance. A polymer film substrate is irradiated with &#x3b3;-rays, electron beams or other radiations to perform multi-graft polymerization with functional monomers and then the polymer film substrate containing the grafted molecular chains or the graft molecular chains into which sulfonic acid groups have been introduced is crosslinked by irradiation to produce a polymer electrolyte membrane that has outstanding oxidation resistance, dimensional stability, electrical conductivity and methanol resistance and which can be controlled in ion-exchange capacity over a wide range.

Highly durable polymer electrolytic membrane for a fuel cell having a cross-linked structure

Process for producing hybrid ion-exchange membranes comprising functional inorganics and graft polymer and electrolyte membranes for use in fuel cells comprising the hybrid ion-exchange membranes

An aromatic polymer film substrate, or a grafted aromatic polymer film substrate having a monomer introduced therein as graft chains is irradiated with ionizing radiation to impart a crosslinked structure. The aromatic polymer film substrate or the grafted aromatic polymer film substrate, provided with the crosslinked structure, is directly sulfonated to obtain a crosslinked aromatic polymer electrolyte membrane. The crosslinked aromatic polymer electrolyte membrane has low water uptake, high proton conductivity, low methanol permeability, high chemical stability, and excellent mechanical characteristics. A method for producing the crosslinked aromatic polymer electrolyte membrane is also provided.

Crosslinked aromatic polymer electrolyte membrane and method for producing same

A polymer film substrate is irradiated with ions to make a large number of nano-sized through-holes and the substrate is further irradiated with an ionizing radiation so that a functional monomer is grafted or co-grafted onto a surface of the film and within the holes; in addition, the sulfonic acid group is introduced into the graft chains, thereby producing a polymer ion-exchange membrane that has high oxidation resistance, dimensional stability, electrical conductivity and methanol resistance, as well as an ion-exchange capacity controlled over a wide range.

In an electrolytic cell a membrane consisting of dielectric material such as an organic polymer, which separates two chambers of the electrolytic cell from each other is produced using an etching solution which is provided in one of the chambers, contains active etching ions, while the other chamber contains a solution, which does not have an etching action. An electrical field is generated through the membrane. The etching progresses along ion tracks in the membrane and first produces one funnel-shaped pore per ion track. Immediately prior to the breakthrough, the ions, which do not have an etching action, begin to penetrate the still existent thin layer with fine pores&#x2014;the active layer&#x2014;and displace the ions with an etching action. An intensified electric current, driven by the adjacent field, is established and the etching process at the bottom of the pore shifts sideways according to the concentration of etching ions still present. The process is stopped by deactivating the field and flushing the membrane.

Method for etching at least one ion track to a pore in a membrane and electrolyte cell for preparing the membrane

A nonlinear device of the present invention includes: a first electrode and a second electrode at least partially opposing each other; and a nonlinear resistant layer made of a material mainly containing zinc sulfide, formed so as to be in contact with the first electrode and the second electrode, wherein at least one of the first electrode and the second electrode is made of an electrode material satisfying a relationship .DELTA.G.sub.M -.DELTA.G.sub.Zn &gt;0, where .DELTA.G.sub.M is standard free energy of a generation reaction of a sulfide of the electrode material and .DELTA.G.sub.Zn is standard free energy of a generation reaction of a sulfide of zinc.

Nonlinear device

Growing community of inventors

Nara, Japan

Masaru Yoshida