A hyperelasticity modelling approach is employed for capturing various and complex mechanical behaviours exhibited by macroscopically isotropic polydomain liquid crystal elastomers (LCEs). These include the highly non-linear behaviour of nematic-genesis polydomain LCEs, and the soft elasticity plateau in isotropic-genesis polydomain LCEs, under finite multimodal deformations (uniaxial and pure shear) using in-house synthesised acrylate-based LCE samples. Examples of application to capturing continuous softening (i.e., in the primary loading path), discontinuous softening (i.e., in the unloading path) and auxetic behaviours are also demonstrated on using extant datasets. It is shown that our comparatively simple model, which breaks away from the neo-classical theory of liquid crystal elastomers, captures the foregoing behaviours favourably, simply as states of hyperelasticity. Improved modelling results obtained by our approach compared with the existing models are also discussed. Given the success of the considered model in application to these datasets and deformations, the simplicity of its functional form (and thereby its implementation), and comparatively low(er) number of parameters, the presented isotropic hyperelastic strain energy function here is suggested for: (i) modelling the general mechanical behaviour of LCEs, (ii) the backbone in the neo-classical theory, and/or (iii) the basic hyperelastic model in other frameworks where the incorporation of the director, anisotropy, viscoelasticity, temperature, softening etc parameters may be required.
This content will become publicly available on February 1, 2025
- Award ID(s):
- 2146409
- NSF-PAR ID:
- 10486366
- Publisher / Repository:
- The American Society of Mechanical Engineers
- Date Published:
- Journal Name:
- Journal of Applied Mechanics
- Volume:
- 91
- Issue:
- 2
- ISSN:
- 0021-8936
- Subject(s) / Keyword(s):
- liquid crystal elastomers polydomain phase transformation thermomechanical coupling
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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