Unbinding Transition of the $\alpha$-BN Phase of BABCB Tetrablock Terpolymers

We study the phase behaviour of BABCB/B multiblock terpolymer/homopolymer blends using real-space self-consistent field theory. We focus on the effects of the added homopolymers on the structure of the $\alpha$-BN phase, formed in the pure BABCB system. In the $\alpha$-BN phase, the A and C blocks form spheres sitting on a three dimensional layered structure, resembling that of graphite. Our results demonstrate that the added homopolymers would aggregate in the regions between the layers in the $\alpha$-BN phase. We use this property of the added homopolymers as a mechanism for separating the layers. By examining the effects of homopolymer/multiblock interactions and their relative degree of polymerization on the overall phase behaviour of the system, we identified a critical homopolymer concentration at which the layers composed of A/C spheres unbind to form free standing sheets, resembling the structure of graphene.