(265e) A Model for Self- Assembly in Side Chain Liquid Crystalline Block Copolymers

We present a new model based on self consistent field theory approach to characterize the self assembly phase behavior in side-chain liquid crystalline block copolymers. Our model considers a micromechanical representation of flexible coil-coil diblock copolymer, with liquid crystalline units (rod-like) being grafted to one of the blocks. We present results elucidating the interplay between block copolymer microphase separation and the orientational ordering of the rod segments. We compute the phase diagram for this system under the assumption of 2D variations in density profiles to study the various morphologies exhibited by the system. The equilibrium phase morphologies are observed to be dependent on the molecular weight of the copolymer, the length of the rod units, the relative volume fractions of the each block, and the energetic and/or orientational interactions between different components. The phase diagrams were asymmetric due to the interplay of block copolymer segregation and orientational ordering. Traditional diblock copolymer microphases were observed for this polymer, with smectic ordering within these microphases. Moreover, microphase separation was observed to be a requisite for developing orientational ordering between mesogenic units.