  The self-assembly of block copolymers containing rigid blocks have received
abiding attention due to its rich phase behavior and potential for use in a
variety of applications. In this work, under asymmetric interactions between
rod/coil components, the self-assembly of coil/coil/rod ABC triblock copolymers
is studied using self-consistent field of lattice model. In addition to
micelles, centrosymmetric lamellae (CSLM), lamellae, perforated lamellae,
strips and gyroids, non-centrosymmetric (NCSLM) lamellae and wavy morphologies
are observed as stable phases. The phase diagram of interaction between rod and
coil components versus the rod fraction is constructed given a fixed
interaction between coil components. For intermediate rod fraction, degenerate
behavior is observed. NCSLM and CSLM are degenerate structures. It is found
that the entropy of chain conformation plays an important role for this rich
behavior. A mechanism of the degenerate behavior is proposed in coil/rod block
copolymers under noncofinement. This study provides some new insights into the
degenerate behavior of block compolymers, which can offer a theoretical
reference for related experiments.
