Author, as appears in the article.: Belmonte A; Lama G; Cerruti P; Ambrogi V; Fernández-Francos X; De La Flor S
Department: Enginyeria Mecànica
URV's Author/s: De la Flor Lopez, Silvia / Fernández Francos, Xavier
Keywords: Thermosets Stresses Shape-shifting Polymers Network structure Liquid-crystalline network Liquid-crystalline elastomers Free-standing Experimental study Epoxy click systems Dual-curing Behavior Actuator
Abstract: © 2018 IOP Publishing Ltd. In this work, free-standing shape-memory thermally triggered actuators are developed by laminating 'thiol-epoxy'-based glassy thermoset (GT) and stretched liquid-crystalline network (LCN) films. A sequential curing process was used to obtain GTs with tailored thermomechanical properties and network relaxation dynamics, and also to assemble the final actuator. The actuation extent, rate and time were studied by varying the GT and the heating rate in thermo-actuation with an experimental approach. The results demonstrate that it is possible to tailor the actuation rate and time by designing GT materials with a glass transition temperature close to that of the liquid-crystalline-to-isotropic phase transition of the LCN, thus making it possible to couple the two processes. Such coupling is also possible in rapid heating processes even when the glass transition temperature of the GT is clearly lower than the isotropization temperature of the LCN, depending on the network relaxation dynamics of the GT and the presence of thermal gradients within the actuators. Interestingly, varying the GT network relaxation dynamics does not affect the actuation extent. As predicted by the analytical model developed in our previous work, the modulus of the GT layer is mainly responsible for the actuation extent. Finally, to demonstrate the enhanced control of the actuation, specifically designed actuators were assembled in a three-dimensional actuating device able to make complex motions (including 'S-type' bending). This approach makes it possible to engineer advanced functional materials for application in self-adaptable structures and soft robotics.
Thematic Areas: Signal processing Química Mechanics of materials Materials science, multidisciplinary Materials science (miscellaneous) Materials science (all) Materials science Materiais Interdisciplinar Instruments & instrumentation General materials science Engenharias iii Engenharias ii Electrical and electronic engineering Condensed matter physics Civil and structural engineering Atomic and molecular physics, and optics
licence for use: https://creativecommons.org/licenses/by/3.0/es/
ISSN: 1361665X
Author's mail: xavier.fernandez@urv.cat silvia.delaflor@urv.cat
Author identifier: 0000-0002-3492-2922 0000-0002-6851-1371
Record's date: 2024-09-07
Papper version: info:eu-repo/semantics/acceptedVersion
Link to the original source: https://iopscience.iop.org/article/10.1088/1361-665X/aac278
Licence document URL: https://repositori.urv.cat/ca/proteccio-de-dades/
Papper original source: Smart Materials And Structures. 27 (7):
APA: Belmonte A; Lama G; Cerruti P; Ambrogi V; Fernández-Francos X; De La Flor S (2018). Motion control in free-standing shape-memory actuators. Smart Materials And Structures, 27(7), -. DOI: 10.1088/1361-665X/aac278
Article's DOI: 10.1088/1361-665X/aac278
Entity: Universitat Rovira i Virgili
Journal publication year: 2018
Publication Type: Journal Publications