Four-dimensional printed liquid crystalline elastomer actuators with fast photoinduced mechanical response toward light-driven robotic functions

Remote light exposure of photoresponsive liquid crystalline polymers has drawn great attention over the last years as an attractive strategy to generate mechanical work with high spatial resolution. To tailor these materials into practical engineering devices, it is of key importance to gain control...

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Detalles Bibliográficos
Autores: Ceamanos, Lorena, Kahveci, Zehra, López-Valdeolivas, María, Liu, Danqing, Broer, Dirk J., Sánchez-Somolinos, Carlos
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2020
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/367505
Acceso en línea:http://hdl.handle.net/10261/367505
Access Level:acceso abierto
Palabra clave:Liquid crystalline polymers
Soft robotics
3D printing
4D printing
Descripción
Sumario:Remote light exposure of photoresponsive liquid crystalline polymers has drawn great attention over the last years as an attractive strategy to generate mechanical work with high spatial resolution. To tailor these materials into practical engineering devices, it is of key importance to gain control over their morphology and thus precisely program their mechanical response, which must also be fast and relevant in magnitude. In this communication, we report the four-dimensional (4D) printing of azobenzene-containing liquid crystalline elastomers (LCEs) that respond to light. During extrusion of the LCE precursor, mesogen orientation is defined by the needle’s moving direction enabling a precise definition of the director, which is later fixed by photopolymerization. Fast mechanical responses have been observed in these 4D printed LCE elements when excited with ultraviolet (UV) light. These 4D printed elements lift objects many times heavier than their own weight, demonstrating a capacity to produce effective work. Photochemical and photothermal contributions to the deformation and force have been identified. Advantageously, the use of blue and UV light excitation enables adjustment of generated forces that can be maintained even in the dark and can be released by light excitation or temperature. The demonstrated ability to generate light-responsive elements quickly delivering sufficient work paves the way for implementing remotely addressed mechanical functions to future soft robotics and engineering.