Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Advances in Mechanochromic Fibers Based on Cholesteric Liquid Crystal Elastomers

콜레스테릭 액정 엘라스토머 기반 메카노크로믹 섬유의 최신 연구 동향

  • Ji Won Lee (Department of Polymer Engineering, Pukyong National University) ;
  • Yu Jin Jeong (Korea Institute of Materials Convergence Technology) ;
  • Soon Mo Park (Department of Chemical and Biomolecular Engineering, Cornell University) ;
  • Dae Seok Kim (Department of Polymer Engineering, Pukyong National University)
  • 이지원 (국립부경대학교 고분자.화학소재공학부 고분자공학전공) ;
  • 정유진 (한국소재융합연구원) ;
  • 박순모 ;
  • 김대석 (국립부경대학교 고분자.화학소재공학부 고분자공학전공)
  • Received : 2025.09.13
  • Accepted : 2025.09.25
  • Published : 2025.10.10
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Abstract

Cholesteric liquid crystal elastomers (CLCEs) are hybrid materials that combine the optical properties of liquid crystals with the elasticity of polymer networks, exhibiting mechanochromic responses through reversible pitch changes under external stimuli. While film-based studies have been essential for elucidating fundamental mechanisms, their limited flexibility and adaptability to multiaxial deformation have restricted applications in wearable displays and smart textiles. To address these challenges, recent efforts have focused on developing CLCEs in fiber geometries. Printing-based fibers, fabricated via direct ink writing, enable complex three-dimensional architectures and multi-mode optical responses. Tubular fibers utilize hollow structures to achieve enhanced flexibility and highly sensitive color changes, making them suitable for robotic skin and stress visualization. High-strength fibers with improved durability and flexibility have also demonstrated compatibility with weaving and knitting processes, highlighting their feasibility for practical integration. This review summarizes the structures, fabrication strategies, and emerging applications of mechanochromic CLCE fibers, providing perspectives for their future development.

콜레스테릭 액정 엘라스토머(cholesteric liquid crystal elastomer, CLCE)는 액정의 광학적 특성과 고분자 네트워크의 탄성적 특성이 결합된 소재로, 외부 자극에 따른 나선 피치 변화로 구조색이 가역적으로 변하는 메카노크로믹 응답을 나타낸다. 기존 필름 기반 연구는 CLCE의 기본 메커니즘 규명에 중요한 역할을 했으나, 웨어러블 디스플레이나 스마트 텍스타일 응용에는 기계적 유연성과 다축 변형 순응성의 한계가 있었다. 이를 극복하기 위해 최근에는 CLCE를 섬유 형태로 구현하는 연구가 활발히 진행되고 있다. 프린팅 기반 섬유는 직접 잉크 쓰기(direct ink writing)를 통해 자유로운 3차원 구조와 다중 모드 응답을 구현하며, 위장 및 메모리 센서 응용 가능성을 보여주었다. 튜브형 섬유는 중공 구조를 활용해 높은 유연성과 민감한 색 변화를 달성하였고, 로봇 스킨이나 응력 시각화에 적합한 특성을 나타냈다. 또한 고강도 섬유는 기계적 내구성과 유연성을 확보하여 실제 직조·편직 공정 적용 가능성을 입증하였으며, 웨어러블 및 산업 안전 분야로 확장될 수 있음을 보여주었다. 본 리뷰에서는 CLCE 메카노크로믹 섬유의 구조, 제작기법, 응용 전망을 고찰하였다.

Keywords

Acknowledgement

이 논문은 2025학년도 국립부경대학교의 글로벌 공동연구 지원을 받아 수행된 연구임 (202505970001).

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