The highly regular hexagonally perforated lamellar (HPL) structure, which is metastable with respect to the gyroid (G) phase in quiescent diblock copolymers, was investigated. The two polystyrene-poly(ethylene-alt-propylene) S/EP were synthesized by sequential anionic polymerization of styrene and then isoprene, and the polysisoprene block selectively hydrogenated to EP. It was observed that anionically polymerized block copolymers showed compositional polydispersity between chains, which in principle permits equilibrium coexistence of ordered phases. The results show that quenching S/EP 9/14 from the G phase at 290 and 230°C did not produce any signature of the HPL structure even after 7 h.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry