Pressure Effects on Self-assembly in Charged Block Copolymer Systems*

Self-assembly in charged A-B block copolymers or their blends with homopolymer C to form nanophases is investigated through field-theoretic calculations. In particular, free volume is allowed in the chosen systems to focus on pressure effects on the self-assembly. The free energy consists of that from charged hard sphere chain reference system and nonbonded dispersion interactions. After the proper discretization of given system, the non-ideal part of the resultant chemical potential is used to determine the local aggregation of charged and uncharged monomers under applied pressure in a mean-field level. In addition to conventional effective Flory-Huggins interaction parameter between dissimilar monomers, ion-ion correlations are shown to affect the self-assembly and its pressure response of the given systems. We will discuss comparison between the present study and inhomogeneity in lipids or other charged amphiphiles under pressure.