Rational design of linear-dendritic block copolymer for overwhelming region of spherical phases

Various ordered structures can be formed by the self-assembly of block copolymer, while the formation of some sophisticated phases among them is usually driven by some sophisticated mechanisms. Several mechanisms have been established to expand the spherical region, thus stabilizing some new spherical phases, e.g. Frank-Kasper phases. However, the effect of these mechanisms is still limited. In order to widen the phase regions of these desired new spherical phases drastically, we start from an intuitive hypothesis, design a kind of linear-dendritic block copolymer and investigate its self-assembly behaviors with the self-consistent field theory (SCFT). Under the optimized control parameters, the spherical phase region is expanded to be overwhelmingly large in the phase diagram and at the same time the regions of Frank-Kasper phases are largely expanded. The most important conclusion is that the discrete spherical domains can be formed by the major component with volume fraction around 0.7. These results renew our insight into the intricate mechanisms of the self-assembly of block copolymer.