6533b85efe1ef96bd12c0501

RESEARCH PRODUCT

Ferroelectric Liquid Crystalline Elastomers

subject

description

Ferroelectric LC-elastomers represent an interesting class of material because they combine the ordering of liquid crystalline ferroelectric phases and the rubber elasticity of polymer networks. Switching of the electric polarization leads to deformation of the polymer network, equivalent to stretching a spring, and creates a stress in the network of polymer chains. The interaction of mesogens and the network can be varied by using different topologies of net points: Crosslinking is carried out either within the siloxane sublayers (leading to fast switching elastomers) or between the siloxane sublayers (resulting in an elastomer that favors the ferroelectric switching state in which the cross-linking reaction took place). Because the orientation of the smectic phase couples to the polymer network, electromechanical measurements show a piezoelectric effect. Mechanical deformation leads to polarization or an external electric field to deformation of the sample. Applying the electric field parallel to the smectic layer structure leads to an extremly high electrostrictive strain. Keywords: ferroelectric liquid crystals; polymer networks; spontaneous polarization; orientation in elastic fields; surface topography of layered materials; piezoeffect