The shear behavior of a doubly anchored brush of liquid-crystalline polymers immersed in a nematic solvent is investigated. In such a brush the grafted polymers bridge two plates. Remarkably, the Franck nematic elasticity in this system can dominate the shear modulus. In the presence of a field the system undergoes a Fréedericksz transition modified by the bridging polymers. In particular: (i) the polymeric elasticity affects the critical field ${\mathit{E}}_{\mathit{c}}$; (ii) the shear modulus vanishes as the field approaches ${\mathit{E}}_{\mathit{c}}$; and (iii) the nematic distortion couples to a shear strain. The system exhibits quasipiezoelectricity, which is nonlinear and is not associated with any inverse effect.

• Received 27 August 1993

DOI:https://doi.org/10.1103/PhysRevE.49.R986