Using a mean-field model, we have studied the phase behavior of a colection of semiflexible polyelectrolytes with electrostatic and anisotropic excluded volume interactions. The interference between the second-order critical phenomenon in the flexible limit and the first-order isotropic-nematic phase transition in th rod limit is found to be richly depenent on the intrinsic chain stiffness, polymer concentration, salt concentration, and temperature through the Flory-Huggins X parameter. For intrinsic chain stidffness below a critical value, there exists only a critical point and a coexistence curve between two isotropic phases. For smaller values of stiffness, but above the critical value, we have found a triple point corresponding to the coexistence of two isotropic phases and one anisotroic phase. As the chain stiffiness is increased progressively, the triple point moves towards lower polyelectrolyte concentration and approaches the critical point. If the chain stiffness is increasee even more, another triple point emerges corresponding the coexistence of oneisotropic phase and two anisotropic phases.
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