Binary mixtures of liquid crystal diacrylates with a stilbene moiety were produced. The mixtures were uniaxially oriented and subsequently photopolymerized, resulting in anisotropic networks with a uniaxial molecular orientation containing stilbene groups in the E (trans) form. In order to avoid E-Z (trans-cis) isomerization of the stilbene groups during polymerization, the wavelength used to initiate polymerization was chosen to be beyond the absorption band of the stilbene molecules. Transformation of the stilbene groups within the uniaxially oriented networks from the E to the Z form was carried out using UV radiation. As a result of the transformation, the conformation and the polarizability of the stilbene molecules were altered,leading to a decrease in the birefringence of the anisotropic networks. The magnitude of the decrease could be varied by the UV exposure time and the fraction of stilbene moieties within the networks. The E-Z isomerization also caused anisotropic dimensional changes and altered the anisotropic thermal expansion behavior of the networks.