Perpendicular Lamellae in Parallel Lamellae in a Hierarchical CECEC-P Hexablock Terpolymer

We describe the synthesis and phase behavior of a nearly monodisperse poly(cyclohexylethylene-b-ethylene-b-cyclohexylethylene-b-ethylene-b-cyclohexylethylene-b-ethylene-alt-propylene) (CECEC-P) hexablock terpolymer, synthesized by sequential anionic polymerization followed by catalytic hydrogenation. This multiblock copolymer, which contains equal volume fractions of P and compositionally symmetric CECEC, microphase separates through chemical incompatibility between C, E, and P and exhibits a complex morphology with two different length scales related to the local (C-E) and overall (C-E-P) sequences. We have identified a perpendicular lamellae in parallel lamellae mesostructure in the CECEC-P sample; where layers of rubbery P separate sheets of alternating layers of semicrystalline E and glassy C, arranged perpendicular to the larger overall lamellar structure.