Electromechanical deformation of dielectric nematic elastomers accompanied by the rotation of mesogens

2022 ◽  
pp. 107061
Author(s):  
Yiwei Xu ◽  
Yiqing Zhang ◽  
Yongzhong Huo
Keyword(s):  
Nematic Elastomers ◽  
Electromechanical Deformation

scholarly journals Internal constraints and arrested relaxation in main-chain nematic elastomers

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Takuya Ohzono ◽  
Kaoru Katoh ◽  
Hiroyuki Minamikawa ◽  
Mohand O. Saed ◽  
Eugene M. Terentjev
Keyword(s):  
Mechanical Properties ◽  
Main Chain ◽  
Polymer Networks ◽  
Nematic Order ◽  
Nematic Elastomers ◽  
Nematic Director ◽  
Highly Nonlinear ◽  
Nonlinear Mechanical ◽  
Liquid Crystal Elastomers ◽  
Memory Applications

AbstractNematic liquid crystal elastomers (N-LCE) exhibit intriguing mechanical properties, such as reversible actuation and soft elasticity, which manifests as a wide plateau of low nearly-constant stress upon stretching. N-LCE also have a characteristically slow stress relaxation, which sometimes prevents their shape recovery. To understand how the inherent nematic order retards and arrests the equilibration, here we examine hysteretic stress-strain characteristics in a series of specifically designed main-chain N-LCE, investigating both macroscopic mechanical properties and the microscopic nematic director distribution under applied strains. The hysteretic features are attributed to the dynamics of thermodynamically unfavoured hairpins, the sharp folds on anisotropic polymer strands, the creation and transition of which are restricted by the nematic order. These findings provide a new avenue for tuning the hysteretic nature of N-LCE at both macro- and microscopic levels via different designs of polymer networks, toward materials with highly nonlinear mechanical properties and shape-memory applications.

A large-strain phase-field model for nematic elastomers based on Landau-de-Gennes theory

PAMM ◽  
2017 ◽  
Vol 17 (1) ◽  
pp. 437-438 ◽  
Author(s):  
Marc-André Keip ◽  
Omkar Nadgir
Keyword(s):  
Phase Field ◽  
Field Model ◽  
Large Strain ◽  
Phase Field Model ◽  
Nematic Elastomers ◽  
Gennes Theory

Elastic energies for nematic elastomers

2009 ◽  
Vol 29 (2) ◽  
pp. 191-204 ◽  
Author(s):  
A. DeSimone ◽  
L. Teresi
Keyword(s):  
Nematic Elastomers

scholarly journals From nonlinear to linearized elasticity via Γ-convergence: The case of multiwell energies satisfying weak coercivity conditions

2014 ◽  
Vol 25 (01) ◽  
pp. 1-38 ◽  
Author(s):  
V. Agostiniani ◽  
T. Blass ◽  
K. Koumatos
Keyword(s):  
Coercivity Conditions ◽  
Coercivity Condition ◽  
Nematic Elastomers ◽  
Linearized Elasticity ◽  
Γ Convergence

Linearized elasticity models are derived, via Γ-convergence, from suitably rescaled nonlinear energies when the corresponding energy densities have a multiwell structure and satisfy a weak coercivity condition, in the sense that the typical quadratic bound from below is replaced by a weaker p bound, 1 < p < 2, away from the wells. This study is motivated by, and our results are applied to, energies arising in the modeling of nematic elastomers.

scholarly journals Supersoft Elasticity in Polydomain Nematic Elastomers

2009 ◽  
Vol 103 (3) ◽  
Author(s):  
J. S. Biggins ◽  
M. Warner ◽  
K. Bhattacharya
Keyword(s):  
Nematic Elastomers

scholarly journals UV isomerisation in nematic elastomers as a route to photo-mechanical transducer

2002 ◽  
Vol 9 (S1) ◽  
pp. 427-434 ◽  
Author(s):  
J. Cviklinski ◽  
A.R. Tajbakhsh ◽  
E.M. Terentjev
Keyword(s):  
Nematic Elastomers ◽  
Mechanical Transducer

scholarly journals Relaxation of nonlinear elastic energies involving the deformed configuration and applications to nematic elastomers

2019 ◽  
Vol 25 ◽  
pp. 19 ◽  
Author(s):  
Carlos Mora-Corral ◽  
Marcos Oliva
Keyword(s):  
Sobolev Space ◽  
Elastic Energy ◽  
Lower Semicontinuous ◽  
Deformation Gradient ◽  
Variational Model ◽  
Nematic Elastomer ◽  
Nematic Elastomers ◽  
Lower Semicontinuous Envelope ◽  
Nonlinear Elastic

We start from a variational model for nematic elastomers that involves two energies: mechanical and nematic. The first one consists of a nonlinear elastic energy which is influenced by the orientation of the molecules of the nematic elastomer. The nematic energy is an Oseen–Frank energy in the deformed configuration. The constraint of the positivity of the determinant of the deformation gradient is imposed. The functionals are not assumed to have the usual polyconvexity or quasiconvexity assumptions to be lower semicontinuous. We instead compute its relaxation, that is, the lower semicontinuous envelope, which turns out to be the quasiconvexification of the mechanical term plus the tangential quasiconvexification of the nematic term. The main assumptions are that the quasiconvexification of the mechanical term is polyconvex and that the deformation is in the Sobolev space W1,p (with p > n − 1 and n the dimension of the space) and does not present cavitation.

Impact of Crystallites in Nematic Elastomers on Dynamic Mechanical Properties and Adhesion

2021 ◽  
Author(s):  
Takuya Ohzono ◽  
Hiroyuki Minamikawa ◽  
Emiko Koyama ◽  
Yasuo Norikane
Keyword(s):  
Mechanical Properties ◽  
Dynamic Mechanical Properties ◽  
Dynamic Mechanical ◽  
Nematic Elastomers
Sign in / Sign up

Export Citation Format

Share Document