폴리에테르설폰(PES)과 폴리페닐렌설파이드설폰(PPSS)을 블렌딩한 고분자를 이용하여 음이온교환막을 제작하였다. EDXS와 FT-IR 분석으로부터 제작한 음이온교환막이 음이온교환기인 -N-을 갖는다는 것을 확인하였다. 1 mol/L의 황산 용액에서 이온전도도를 측정하였다. 제작한 음이온교환막은 0.015~0.083 S/cm의 이온전도도를 가졌으며, 시판의 음이온교환막인 AFN과 APS의 값과 비교하여 동등 이상의 값을 가졌다. 제작한 음이온교환막의 바나듐 레독스 흐름 전지용 격막으로 사용한지를 평가하기 위해 각 바나듐 이온의 투과를 측정하였다. 제작한 음이온교환막의 각 바나듐 이온의 투과도는 시판의 양이온교환막인 Nafion 117과 시판의 음이온교환막인 AFN과 비교하여 낮은 값을 가졌다.

Polymer electrolyte membrane fuel cells (PEMFCs) have been studied intensively due to their great potential as a clean and efficient energy conversion device. Especially, considerable attention has been paid to the development of thin polymer electrolyte membranes (PEMs) for the practical application of PEMFCs. However, thin PEMs normally have poor physicochemical stability. It is well-known that the physicochemical stability of polymer membrane can be improved by cross-linking technology. In this presentation two different types of cross-linked membranes from sulfonated poly(arylene ether sulfone) (SPAES) will be introduced: 1) cross-linked SPAES membranes prepared using flexible perfluoropolyether as a cross-linker. 2) End group cross-linked SPAES membranes prepared via simple thiol-ene click reaction.

Anion exchange membrane fuel cells (AEMFCs) have attracted a growing interest as an alternative for proton exchange membrane fuel cells (PEMFCs). AEMs are the most important components of AEMFCs, and it’s a great challenge to attain high ion conductivity, good dimensional, mechanical and alkaline stabilities for AEMs. We prepared poly(ether sulfone ketone)s having various hydrophilic-hydrophobic block ratios, and investigated the effect of the block composition on the chemo-physical properties of the corresponding membranes. The experimental procedures and the properties, including conductivity, morphology and stability will be discussed in detail.

Anion exchange membrane fuel cells (AEMFCs) have been considered as a promising energy device. To make highly efficient AEMs, high ion conductivity, mechanical stabilities and alkaline stabilities are required. High ion conductivity generally accompanies poor mechanical properties, and crosslinking has been widely applied to overcome these problems. Our groups introduced novel terminally-crosslinked piperidinium-functionalized poly(arylene ether sulfone)s as a anion exchange membrane. Unlike the typical AEMs, our terminally-crosslinked membranes are expected to have high conductivity, especially at low RH conditions due to enhanced water-holding capacity, while maintaining the high chemophyscial stabilities by crosslinking. The synthesis, and properties of the prepared membranes will be discussed in detail.

Chlor-alkali (CA) membrane process is a commercially useful process to produce valued chemicals such as chlorine, sodium hydroxide and hydrogen via salined water electrolysis using sodium ion (Na+)-selective membranes. The most important issue in CA process is to reduce high energy consumption. A plausible solution is to obtain highly Na+-conductive membranes. The representative membrane materials are chemically stable perfluorinated sulfonic acid (PFSA) ionomers such as Nafion® and Aciplex®. PFSA membranes, but it is necessary to develop alternatives to PFSA membranes. In this study, a sulfonated poly(arylene ether sulfone) copolymer membrane is radiation-grafted with a highly sulfonated poly(styrene) used as a side chain material.

Sulfonated poly(arylene ether sulfone) (SPAES) random copolymers have been perceived as alternatives to perfluorinated sulfonic acid (PFSA) ionomers owing to their cheap production cost and low hydrogen permeability. In spite of their advantages, there are some issues to overcome such as membrane durability and relatively low proton conductivity in the low humidity range. An approach to solve these problems is to fill SPAES copolymers into porous support films (e.g., poly(tetra fluoro ethylene), PTFE). However, it is difficult to make defect-free pore-filling membranes. In this study, SPAES nanodispersion in a water-alcohol mixture is made under a modified supercritical condition and used to make highly proton conductive and chemical durable SPAES-PTFE pore-filling membranes.

본 연구에서는 고분자 전해질 연료전지(PEFC)의 전해질막의 화학적 안정성의 향상을 위하여 3-mercaptopropyl silica gel (3MPTSG)과 poly(arylene ether sulfone)(SPAES)을 이용하여 복합막을 제조하였다. 일반적으로 방향족 탄화수소계 고분자막은 전극 부분에서 발생한 라디컬에 의한 고분자 산화가 일어나 내구성이 감소하게 되는데 이는 대부분 주쇄에 포함 된 에테르 기 부분의 취약성으로 발생한다. 본 연구에서는 이러한 라디칼에 의한 고분자 주쇄의 산화를 방지하기 위해 친수 성의 무기물 입자를 도입하여 이온전도도 감소율을 최소화하고 산화안정성을 높이고자 하였다. 복합막들의 물성 및 전기화학 적 특성을 평가하기 위해 접촉각, FT-IR, 이온전도도, 이온교환용량(IEC), 함수율, 열안정성 등을 수행하였다. 실리카의 함량 이 0에서 0.5%까지 증가함에 따라 이온전도도 및 함수율은 각각 10% 감소한 0.076 S cm-1 및 16% 감소한 24.6 wt%이었으 나, 산화안정성은 10% 향상되었다.

Polymer electrolyte membrane fuel cells (PEMFC) are considered as prospective energy conversion systems because of high efficiency and environmental advantage. However, the current PEMFC technology uses commercialized perfluorosulfonic acid (PFSA) polymers as a proton exchange membrane, which has the issues of high production cost, poor recyclability at intermediate temperature. In this study, We have synthesized a non-fluorinated hydrocarbon membrane. Also, non-fluorinated membrane has a symmetric chemical structure and sulfonated block copolymer was prepared and characterized using 1H-NMR, and the proton conductivity, ion exchange capacity (IEC), and water uptake. properties were evaluated. The synthesis, characteristic and fuel cell performance and newly prepared membrane will be discussed.

Salined water electrolysis is one of representative commercial processes to produce valued chemicals such as chlorine, hydrogen. The most important issue in the electrolysis is to reduce energy consumption. A plausible solution is to accelerate Na+ion transport through cation exchange membranes and to reduce interfacial resistance with electrodes. The conventional membrane materials are based on PFSAs such as Nafion®. In spite of their robust chemical resistance, there are several critical demerits including expensive production cost and difficult tuning capability. For this, a SPAES random copolymer-silica nanocomposite is used as a membrane matrix with a high ionic conductivity and radiation-grafted with a highly sulfonated poly(strylene) to provide a branched polymer architecture for improved interfacial characteristics.

Sulfonated poly(arylene ether sulfone) (SPAES)random copolymers have been perceived as alternatives to perfluorinated sulfonic acid (PFSA) ionomers owing to their cheap production cost and low hydrogen permeability. In spite of their advantages, there are some issues to overcome such as membrane durability and relatively low proton conductivity in the low humidity range. An approach to solve these problems is to fill SPAES copolymers into porous support films (e.g., poly(tetra fluoro ethylene), PTFE). However, it is difficult to make defect-free pore-filling membranes. In this study, SPAES nanodispersion in a water-alcohol mixture is made under a modified supercritical condition and used to make highly proton conductive and chemical durable SPAES-PTFE pore-filling membranes.

Sulfonated poly(arylene ether sulfone) copolymers are prepared by an aromatic substitution polymerization reaction as polymer electrolyte membranes for polymer electrolyte membrane fuel cells (PEMFCs). Thin, ductile films are fabricated by the solution casting method, which resulted in membranes with a thickness of approximately 50μm. The synthesized copolymers and membranes are characterized by 1H NMR, FT-IR, TGA, ion exchange capacity, water uptake and proton conductivity measurements. The prepared membranes are tested in a 9 cm2 commercial single cell at 80 ℃ and 120 ℃ in humidified H2/air under different relative humidity conditions. The prepared membrane is found to perform better than the commercial Nafion 112 membrane at 120℃ under low humidity condition.

리튬이온 이차전지는 리튬이온이 이동하면서 전기화학적 충방전사이클을 완성하는 에너지변환장치를 의미한다. 리튬이온 이차전지는 높은 에너지밀도와 낮은 자가방전률, 상대적으로 긴 수명주기 등 다양한 장점을 갖는다. 최근 전기차 수 요증가는 고용량 리튬이온 이차전지 개발을 촉진하고 있으나 음극에서의 dendrite 형성으로 인한 전기적 단락 현상과 전지 폭 발 문제와 같은 심각한 안전문제를 야기한다. 또한, 리튬이온 이차전지 구동시 상승된 온도에서 폴리올레핀계열(예 : 폴리에 틸렌과 폴리프로필렌) 격리막의 열수축 문제가 발생한다. 이와 같이 낮은 열 안정성은 리튬이온 이차전지의 성능과 수명의 감소로 이어진다. 본 연구에서는 폴리올레핀계열 함침격리막 제조를 위한 중요한 소재로서 술폰화 폴리아릴렌에테르술폰 랜 덤 공중합체를 사용하였으며, 제조된 격리막을 이용하여 dendrite 형성과 관련된 금속이온 흡착 능력과 리튬이온전도성, 열적 내구성이 평가되었다.