Abstract
Equilibrium swelling and phase behavior of two different liquid crystalline (LC) networks swollen in two different nematogenic solvents whose nematic-isotropic phase transition temperatures (T_<NI>^S) are lower than those of the gels (T_<NI>^G) has been investigated as a function of temperature (T) by polarizing microscopy. All the systems examined show essentially the same characteristics in swelling and phase behavior as follows. As temperature decreases, the isotropic gel discontinuously shrinks into the nematic state at T_<NI>^G. At further decreased temperature, the nematic gel shows a continuous reswelling (reentrant swelling) in the region T_<NI>^S < T < T_<NI>^G. At T_<NI>^S, the temperature dependence of equilibrium swelling degree exhibits an inflection. These characteristics of swelling and phase behavior observed well accord with the predictions of a mean-field theory for nematic gel.
