Dual-dynamically crosslinked PVA/chitosan-gallol conjugate hydrogel for wearable sensor

다국어 초록 (Multilingual Abstract)

Flexible wearable electronics have recently driven the rapid development of conductive hydrogels with self-healing capabilities and tissue adhesiveness. Poly(vinyl alcohol)-borax (PB) based hydrogels exhibit ionic conductivity and rapid self-healing behavior, but their practical application in wearable sensors is limited because of insufficient mechanical strength, limited conductivity, and poor adhesion. In this study, chitosan-gallic acid (CSGA) was introduced into the PB hydrogels to overcome these limitations. The CSGA incorporated hydrogels (PBCG) exhibited significantly improved tissue adhesion (3.44 kPa), mechanical strength (18.42 kPa), and electrical conductivity (0.40 S/m). The stabilization process induced self-crosslinking of CSGA, leading to the formation of a hydrogel (PBCG-S) crosslinked via dual dynamic covalent bonds (borate ester bond and Schiff base). The PBCG-S hydrogels demonstrated enhanced mechanical properties (30.7 kPa) and sensitivity (~100% strain, Gauge factor = 0.56) and exhibited excellent self-healing properties (93%). Finally, the PBCG-S hydrogels proved their applicability as a wearable sensor capable of detecting a wide range of body movements and recognition of voice and handwriting.

목차 (Table of Contents)

• 1. 서론 1
• 1.1. 유연한 착용형 센서 1
• 1.2. 자가 치유 수화젤 3
• 1.3. PVA-borax 기반 전도성 수화젤 6
• 1.4. 키토산-갈산 유도체8
• 1.5. 연구 목적 10
• 2. 실험 12
• 2.1. 재료 및 시약 12
• 2.2. CSGA의 합성 12
• 2.3. PBCG-S 수화젤의 제조 13
• 2.4. 특성 분석 14
• 2.4.1. CSGA의 구조적 분석 14
• 2.4.2. 수화젤의 기계적 특성 14
• 2.4.3. 기공 및 광학적 특성 15
• 2.4.4. 접착 특성 16
• 2.4.5. 전기적 특성 16
• 2.5. 통계적 분석 17
• 3. 결과 및 고찰 18
• 3.1. 수화젤의 제조 18
• 3.1.1. CSGA의 합성 18
• 3.1.2. PBCG-S 수화젤의 제조 20
• 3.2. 수화젤의 특성 분석 22
• 3.2.1. 기계적 특성 22
• 3.2.2. 기공 구조, 기계적 유연성 및 광학적 특성 26
• 3.3. CSGA 도입에 따른 수화젤의 특성 분석 29
• 3.3.1. 피로 저항 특성 29
• 3.3.2. 전도도 및 접착 특성 32
• 3.3.3. 자가 치유 특성 35
• 3.4. 센싱 능력 평가 38
• 3.4.1. 전기적 특성 38
• 3.4.2. 신체 움직임 감지 40
• 3.5. 착용형 센서로서의 실질적인 응용 42
• 4. 결론 47
• 5. 참고문헌 48
• ABSTRACT 58