Korea Research Institute of Chemical Technology

Cheil Industries Inc.

Young Taik Hong

Tae Ho Kim

Seog Je Kim

Duk Man Yu

Seok Koo Kim

Dong Hyun Lee

Sang Sung Woo

Jong Chan Won

Kil Yeong Choi

Ji Young Park

Young Jun Yoon

Kyung Seok Yoon

Jang Yong Lee

Soo Jin Park

Seung Yong Jee

Jae Rock Lee

Hyo Joong Kim

Youn S Don

The present invention relates to an ion conducting polymer including a partially branched block copolymer; a method of preparing the same; an ion conductor including the ion conducting polymer; an electrolytic membrane including the ion conducting polymer; a membrane-electrode assembly comprising the electrolytic membrane, and a battery comprising the same; and a separation membrane for a redox flow battery including the ion conducting polymer, and a redox flow battery comprising same. Specifically, the partially branched block copolymer includes: a first block including a hydrophilic first polymer; a second block derived from a hydrophobic second polymer having two or more reactive groups respectively on its both ends, in such a way as to form branching points forming side branches on a main chain; and optionally a third block including a hydrophobic third polymer. The ion conducting polymer in the form of a partially branched block copolymer can prepare a polymer membrane having improved conductivity and superior physical properties such as tensile strength elongation at break, etc., while having the same or similar ion-exchange capacity (IEC), percentage water absorption and/or degree of dimensional change compared to conventional ion conducting polymers in the form of linear block copolymers. Because of such outstanding physical properties, the polymer membrane can be used as a membrane-electrode assembly for a fuel cell, and a redox flow battery comprising the same as a separation membrane can exhibit outstanding cell performance and maintain high discharge charge capacity retention rate even when repeatedly charged and discharged several times.

Ion conducting polymer comprising partially branched block copolymer and use thereof

The present invention relates to an improved method for purifying a sulfonated aromatic monomer. The method is an economical method capable of providing a highly pure sulfonated aromatic monomer, in which a salt precipitation step and a recrystallization step are simplified while maintaining the reaction conditions used in a conventional method for synthesizing the sulfonated aromatic monomer, and a purification process is carried out using an easily available and stable chemical substance. The sulfonated aromatic monomer obtained by the purification method will be useful for the preparation of a polymer for a polymer electrolyte membrane and will be advantageous to synthesize polymer with high molecular weight.

Method for purifying sulfonated aromatic monomer

The present invention provides a method for manufacturing a membrane-electrode assembly for a polymer electrolyte fuel cell, in which the glass transition temperature of an electrolyte membrane is reduced using a hydrophilic solvent, and a membrane-electrode assembly for a polymer electrolyte fuel cell, manufactured by the method. In the method of the invention, the glass transition temperature of the electrolyte membrane to which a catalyst is transferred is reduced compared to that in a conventional method for manufacturing a membrane-electrode assembly for a polymer electrolyte fuel cell using the decal process. Thus, even to an electrolyte membrane material having a relatively high glass transition temperature, the catalyst may be transferred at a rate of 100% at a temperature of about 120&#xb0; C., at which hot pressing is carried out. Thus, the problems associated with electrolyte membrane deterioration occurring in conventional methods can be solved.

Method for manufacturing membrane-electrode assembly for polymer electrolyte fuel cell and membrane-electrode assembly manufactured thereby

A filament type nano-sized lone fiber and a method of producing the same are disclosed. In the method, a spinning solution or a spinning melt is electro-spun in drops using a spinneret to which a critical voltage is applied, and the spun drops are continuously collected on a multi-collector. The spinning solution is produced dissolving a blend or copolymer consisting of two or more kinds of polymers in a solvent. The spinning melt is produced by melting the polymers. The multi-collector is selected from the group consisting of a plate type collector, a roll type collector, and a combination thereof. The filament type nano-sized long fiber is processed into a yarn through one step during the electrospinning process, and thus, mechanical properties are better than those of conventional nanofiber non-woven fabric. Consequently, the filament type nano-sized long fiber can be utilized for the extended application.

Filament bundle type nano fiber and manufacturing method thereof

This invention relates to melt processable copolymer of etherimideimide/etherimide herein-after identified as PEII/PEI copolymer of following structural formula(I). ##STR1## wherein, R and R' are independently selected from the groups of ##STR2## Ar and Ar' are independently selected from the groups of ##STR3## (wherein, R1 is H or C1-C6 alkyl group,

Melt processable etherimideimide/etherimide copolymer

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Daejeon, South Korea

Young Taik Hong