Phase behaviors of side chain liquid crystalline block copolymers

Abstract

The microphase separation of side chain liquid crystalline (SCLC) block copolymers was studied using dissipative particle dynamics (DPD) simulations. The block copolymer monomer consists of flexible A segments and flexible B segments grafted by rigid C side chains, where the A, B and C blocks are incompatible with each other. The phase structures of the SCLC copolymers were found to be controlled by A and C block lengths and the graft number. Various mesophases, such as spheres, cylinders, gyroids, and lamellae, were obtained. Phase stability regions in the space of C block length and A block length (or graft number and A block length) were constructed. The packing ordering of C side chains was also studied, and discovered to increase as the temperature decreases or the rigid C side chains increase. In addition, the results of the SCLC copolymers were compared with those of flexible copolymers and available experimental observations. The simulation results in the present work provide useful information for future investigations on SCLC copolymers.