(28b) A Self-Consistent Field Study of Diblock Copolymer/Charged Particle System Morphologies for Nanofiltration Membranes

A combination of self-consistent field theory and density functional theory was used to examine the stable, equilibrium morphologies of thin films formed by diblock copolymers with a tethered nanoparticle attached either between the two blocks or at the end of one of the blocks. Both neutral and charged particles were examined, with and without interaction potentials between the particles and the blocks. The phase diagrams of the various systems were constructed, with the aim of determining the most appropriate morphologies for application to nanofiltration membrane technology. In particular, we examined the conditions under which periodic, hexagonal arrays of cylinders could be generated wherein the tethered particles would primarily be located within the interface between the two blocks of the copolymer, thus allowing chemical or thermal degradation to tailor a thin membrane composed of hollow channels lined with charged particles to facilitate both charge and steric exclusion in nanofiltration applications. Key factors influencing these properties were determined to be the particle position along the diblock chain, the interaction potentials of the blocks and particles, the volume fraction of the blocks, and the radii of gyration of the blocks.