물리적 성질 향상을 위한 가교 가능한 고분자화 된 이온성 액체의 합성

Abstract

ABSTRACT

Synthesis of cross-linkable poly(ionic liquid) to improve physical properties

Kim, Jun-Bum Advisor: Prof. Jung-Soo Lee, Ph.D. Department of Chemical Engineering Graduate School of Chosun University

We are living with various electrical devices. Also in future society, various electric devices will become an essential element in our life. Therefore, researches related to electric devices are attracting much attention. One of the areas of the greatest interest in relation to electrical devices is the batteries that allow the use of electrical devices. For this reason, various components of the battery are being studied to increase the stability, efficiency and capacity of the battery. Research on the electrodes, electrolytes, and membranes, which are components of the battery, has been carried out variously. However there is a lack of studies on a binder that can affect the performance of the battery with a small amount. The most commonly used binder is polyvinylidene difluoride (PVDF) binder. The PVDF binder is nonconductive and exhibit performance degradation due to the swelling effect. Thus, a new material that replaces the existing PVDF binder is required for the improvement of physical properties. An ionic liquid refers to a substance that can not form a crystal due to the asymmetry of the positive and negative ion sizes and is present as a liquid at room temperature. These ionic liquids have been utilized in various fields such as solvent, electric, electronic, energy and environmental fields based on advantages, for example low vapor pressure, excellent thermal and mechanical stability and low viscosity. Ionic liquids are used as electrolytes in the field of electricity and electronics. We further seek to utilize it as a binder by polymerizing the ionic liquid and improve its physical properties. In this study, two methods that improve the physical properties of ionic liquids were employed to E-beam irradiation and Silanol reaction followed by cross-linking. Prior to confirming the improvement in physical properties, 1H-NMR was conducted to confirm successfully synthesized poly(ionic liquid). After E-beam irradiation and thermal treatment, chemical changes of poly(ionic liquid) were analyzed by FT-IR. After cross-linking, improvement in physical stability was confirmed by DSC and Gel content analyzed. Cross-linked poly(ionic liquid) in CV analysis had exhibited the excellent electrochemical performance. As a result of this study, poly(ionic liquid) were successfully synthesized and improved the physical properties. Thus, new binders show possibility as promising binder in energy storage devices.