Deformation and Elastic Recovery of Acrylate-Based Liquid Crystalline Elastomers

Abstract

Liquid crystalline elastomers (LCEs) are well known for their stimuli-responsive behavior. Of interest to the work presented here is the distinctive, nonlinear deformation of these materials to load. Here, we assess the cyclic deformation and elastic recovery of acrylate-based LCEs synthesized by chain-transfer reactions. Mechanical deformation of the LCEs (prepared with this synthetic approach) beyond a threshold strain value does not elastically recover, unless heat-treated. The thermomechanical actuation of these materials exhibits limited hysteresis over five cycles. Exploration of the deformation mechanics and elastic recovery extends the understanding of this material composition and informs its potential use in applications.

A blend of stretching and bending in nematic polymer networks

“…Thus, work can be done and shape can be changed by light and heat. Needless to say, this opens fascinating scenarios for novel mechanical applications [35][36][37][38][39][40][41][42]. Here, for given s 0 > −1, s > −1 will be the actuation parameter of our theory.…”

Ridge energy for thin nematic polymer networks

“…In [21], we extended the classical Kirchhoff-Love hypothesis [22] to obtain a dimension reduction of F (C f ) in (6), that is, a method that convert f e in (5) into a surface energy-density (to be integrated over S). As standard in the theory of plates, such a surface energy is delivered by a polynomial in odd powers of h, conventionally truncated so as to retain the first two relevant ones, the first and the third power.…”

“…The prompt response to these stimuli, so characteristic of liquid crystals, once transferred to the solid matrix, makes it possible to do work and change the shape of bodies with no direct contact. The possible technological applications of these materials are boundless (see, for example, the papers [1][2][3][4][5][6][7][8][9], and above all the review [10]), but a number of theoretical challenges remain open [11]; this paper is concerned with one of them.…”

“…Clearly, still according to(11), for s > s 0 , which is achieved upon cooling the sample below the crosslinking temperature, the material would expand along m and contract transversely 6. In S, m is extended uniformly away from S, so as to be independent of the x 3 coordinate.…”

Liquid Crystal-Based Organosilicone Elastomers with Supreme Mechanical Adaptability

“…Numerous strategies have been adopted to achieve this goal [6,7]. Among them, the liquid crystal elastomer, as a kind of material which can dissipate energy through reversible internal phase transition under external stimulation and have the recoverable large deformation capacity [8][9][10], becomes one of the best choices for mechanical adaptability materials [11,12]. Since Küpfer and Finkelmann developed a method for the preparation of monodomain liquid crystal elastomers in 1991 [13], the research on liquid crystal elastomers has become a hot topic [14][15][16].…”