• Membrane Journal
• /
• v.34 no.2
• /
• pp.154-162
• /
• 2024

Anion exchange membranes (AEMs) are essential components in water electrolysis systems, serving to physically separate the generated hydrogen and oxygen gases while enabling the selective transport of hydroxide ions between electrodes. Key characteristics sought in AEMs include high ion conductivity and robust chemical and mechanical stability in alkaline. In this study, quaternized Poly(terphenyl piperidinium)/cellulose nanocrystals (qPTP/CNC) mixed matrix membrane was fabricated. The polymer matrix, PTP, was synthesized via super-acid polymerization, known for its excellent ion conductivity and alkaline durability. The qPTP/CNC membrane showed a dense and uniform morphology without significant voids or large aggregates at the polymer-nanoparticle interface. The qPTP/CNC membrane containing 2 wt% CNC demonstrated a high ion exchange capacity of 1.90 mmol/g, coupled with low water uptake (9.09%) and swelling ratio (5.56%). Additionally, the qPTP/CNC membrane showed significantly lower resistance and superior alkaline stability (384 hours at 50℃ in 1 M KOH) compared to the commercial FAA-3-50 membrane. These results highlight the potential of hydrophilic additive CNC in enhancing ion conductivity and alkaline durability of ion exchange membranes.

• Transactions of the Korean hydrogen and new energy society
• /
• v.32 no.6
• /
• pp.524-533
• /
• 2021

In this study, a series of anion conductive organic/inorganic composite membranes with excellent ionic conductivity and chemical stability were prepared by introducing graphene oxide (GO) inorganic nanofiller into the quaternized poly(phenylen oxide (Q-PPO) polymer matrix. The fabricated organic/inorganic composite membranes showed higher ionic conductivity than the pristine membrane. In particular, Q-PPO/GO 0.7 showed the highest ionic conductivity value of 143.2 mS/cm at 90℃, which was 1.56 times higher than the pristine membrane Q-PPO (91.5 mS/cm). In addition, the organic/inorganic composite membrane showed superior dimensional stability and alkaline stability compared to the pristine membrane, and the physicochemical stability was improved as the content of inorganic fillers increased. Therefore, we suggest that the as-prepared organic/inorganic composite membranes are very promising materials for anion exchange membrane applications with high conductivity and alkaline stability.

• 한국신재생에너지학회:학술대회논문집
• /
• 2009.11a
• /
• pp.197-198
• /
• 2009

고분자 전해질막으로 사용할 수 있는 소수성/친수성 랜덤 멀티블럭 공중합체를 합성하였다. 공중합체는 수산화기를 각 말단에 가지고 있는 소수성 올리고머, 친수성 올리고머 및 반응성이 좋은 커플링 단량체로 친핵성 치환 반응을 활용하여 합성 하였다. 높은 반응성의 커플링 단량체의 존재로 비교적 낮은 온도에서 합성이 됨으로서 고온에서의 에테르-에테르 교환반응에 의한 랜덤화를 억제할 수 있었으며, 높은 중합도의 공중합체를 합성 할 수 있었다. 각 수산화기로 같은 말단으로 조정된 올리고머는 투입 비율의 조정으로 쉽게 이온교환용량을 조정할 수 있었다. 솔루션 캐스팅 방법으로 강도를 가지고 잘 휘어지며 투명한 전해질막을 제조할 수 있었다. 전해질막은 이온전도도, 물흡수율, 부피 변화율, 연료 투과성 등의 측정이 되었다.

• Applied Chemistry for Engineering
• /
• v.31 no.6
• /
• pp.603-606
• /
• 2020

A hydrophilic alkaline room temperature ionic liquid electrolyte (RT-IL) carrying hydroxide ion as an anion and 1-benzyl-3-butylimidazolium as a cation was synthesized. Electrochemical, physical and structural properties of the synthesized RT-IL were characterized using cyclic voltammetry, ionic conductivity, viscosity, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), FT-IR, and 1H-NMR measurements. High ionic conductivity and low viscosity characteristics comparable to 0.1 M KCl electrolyte solution were achieved for the RT-IL in addition to a wide electrochemical potential window of about 4.4 V. The results indicate that the RT-IL is promising for future applications as an alternative electrolyte to energy and environmental research fields.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.22 no.1
• /
• pp.145-152
• /
• 2020

Onion is a perennial herb of the lily family that has a long history and has long been widely used throughout the world as it is one of the most important condiments in our diet, along with chili peppers and garlic. It has been used for cooking and processing food with its unique flavor and aroma. Because of the nature of onions, long-term storage can lead to spoilage. Research was done to increase profits through processing and expand various onion products. A low temperature extraction method was used to study the physiological activation effect and onion processing method of flavonoid component weak to heat.

• Membrane Journal
• /
• v.31 no.6
• /
• pp.371-383
• /
• 2021

Anion exchange membranes have been used for water electrolysis, which can produce hydrogen, and fuel cells, which can generate electrical energy using hydrogen fuel. Anion exchange membranes operate based on hydroxide ion (OH^-) conduction under alkaline conditions. However, since the anion exchange membrane shows relatively low ion conductivity and alkaline stability, there is still a limit to its commercialization in water electrolysis and fuel cells. To address these issues, it is important to develop novel anion exchange membrane materials by rationally designing a polymer structure. In particular, the polymer structure and synthetic method need to be controlled. By doing so, for polymers, the physical properties, ionic conductivity, and alkaline stability can be maintained. Among many anion exchange membranes, poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) is commercially available and easily accessible. In addition, the PPO has relatively high mechanical and chemical stability compared to other polymers. In this review, we introduce the recent development strategy and characteristics of PPO-based polymer materials used in anion exchange membranes.

• Membrane Journal
• /
• v.33 no.2
• /
• pp.77-86
• /
• 2023

In this study, pore-filled ion exchange membranes with low membrane resistance and high hydroxide ion conductivity was developed. To improve alkali durability, a porous substrate made of polytetrafluoroethylene was used, and a copolymer was prepared using monomers 2-(dimethyl amino) ethyl methacrylate (DMAEMA) and vinyl benzyl chloride (VBC) for pores. divinyl benzene (DVB) was used as the cross-linker, and ion exchange membranes were prepared for each cross-linking agent content to study the effect of the cross-linker content on DMAEMA-DVB and VBC-DMAEMA-DVB copolymers. As a result, chemical stability is improved by using a PTFE material substrate, and productivity can be increased by enabling fast photo polymerization at a low temperature by using a low-pressure UV lamp. To confirm the physical and chemical stability of the ion exchange membrane required for an anion exchange membrane fuel cell, tensile strength, and alkali resistance tests were conducted. As a result, as the cross-linking degree increased, the tensile strength increased by approximately 40 MPa, and finally, through the silver conductivity and alkali resistance tests, it was confirmed that the alkaline stability increased as the cross-linking agent increased.