The Phase Behavior Of Polyelectrolyte Solution Confined In The Cylinder

Using mean-field dynamic density functional theory(DDFT), the phase behavior of lamella-forming, gyroid-forming, cylinder-forming and sphere-forming polyelectrolyte solutions confined in the cylinder is simulated respectively. The effect of the charges of the solvophilic bead on phase structure is researched in fixed cylinder size. Many new phase structures deviating from the bulk are obtained. It is also found that the phase structures of such four different bulk phase all tend to become disorder with increasing charge. However,there still exists some difference. The phase transitions of lamella-forming and gyroid-forming polyelectrolyte solutions are order ? disorder, while cylinder-forming and sphere-forming polyelectrolyte solutions experience order ? order ? disorder phase transitions. Besides, the order parameter curves and phase diagram of polyelectrolyte solutions are drawn, which show that the higher concentration of the polyelectrolyte solutions,the bigger value of order parameter, and the bigger charge to get disorder.Furthermore, the phase transition of cylinder-forming polyelectrolyte solutions confined in cylinders with different sizes is studied when the charge is fixed. The single helix, double helix, structures with one cylinder at the center of the pore and three flattened cylinders that coil around the pore surface, and structures with one cylinder at the center of the pore and four flattened cylinders that coil around the pore surface are first found in polyelectrolyte solutions, which offer certain theoretical guidance for the application of polyelectrolyte solution.