The need for mechanical manipulation during the curing of conventional liquid crystal elastomers diminishes their applicability in the field of shape-programmable soft materials and future applications in additive manufacturing. Here we report on polymer-dispersed liquid crystal elastomers, novel composite materials that eliminate this difficulty. Their thermal shape memory anisotropy is imprinted by curing in external magnetic field, providing for conventional moulding of macroscopically sized soft, thermomechanically active elastic objects of general shapes. The binary soft-soft composition of isotropic elastomer matrix, filled with freeze-fracture-fabricated, oriented liquid crystal elastomer microparticles as colloidal inclusions, allows for fine-tuning of thermal morphing behaviour. This is accomplished by adjusting the concentration, spatial distribution and orientation of microparticles or using blends of microparticles with different thermomechanical characteristics. We demonstrate that any Gaussian thermomechanical deformation mode (bend, cup, saddle, left and right twist) of a planar sample, as well as beat-like actuation, is attainable with bilayer microparticle configurations.

This work deals with the design and characterization of a new series of liquid crystalline elastomers in the form of monodomain films, showing self-assembling behaviour, namely the nematic and the orthogonal smectic A phases. The procedure for the design and preparation of monodomain and polydomain polysiloxane-based side-chain liquid crystalline elastomers containing different concentrations of two mesogenic monomers and a constant density (about 15 mol%) of the crosslinker is reported. The phase diagram and mesomorphic behaviour of the new resulting liquid crystalline elastomers were determined by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and especially X-ray diffraction studies, which helped to clearly identify the smectic A phase. Among new liquid crystalline elastomer films, a specific concentration of co-mesogens gives an unconventional and fascinating system with a direct transition from the isotropic to smectic A phase. Results of the thermo-mechanic studies confirmed the shape-memory properties of these films, which have elastic properties optimal for applications as thermo-mechanic actuators

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