Highly Asymmetric Phase Diagram of a Poly(1,2-octylene oxide)-Poly(ethylene oxide) Diblock Copolymer System Comprising a Brush-Like Poly(1,2-octylene oxide) Block

Hamley IW; O'Driscoll BMD; Lotze G; Moulton C; Allgaier J; Frielinghaus H

Macromolecular Rapid Communications, Vol.30, No.24, 2141-2146, 2009

DOI10.1002/marc.200900474 Export Citation

Highly Asymmetric Phase Diagram of a Poly(1,2-octylene oxide)-Poly(ethylene oxide) Diblock Copolymer System Comprising a Brush-Like Poly(1,2-octylene oxide) Block

Hamley IW, O'Driscoll BMD, Lotze G, Moulton C, Allgaier J, Frielinghaus H

The phase diagram of a series of poly(1,2-octylene oxide)-poly(ethylene oxide) (POO-PEO) diblock copolymers is determined by small-angle X-ray scattering. The Flory-Huggins interaction parameter was measured by small-angle neutron scattering. The phase diagram is highly asymmetric due to large conformational asymmetry that results from the hexyl side chains in the POO block. Non-lamellar phases (hexagonal and gyroid) are observed near f(PEO) = 0.5, and the lamellar phase is observed for f(PEO) >= 0.5.

Keywords:block copolymers;microphase separation;phase behaviour;phase diagrams