Stability of Ordered Phases in Weakly Segregated Diblock Copolymer Systems

Mohamed Laradji; An-Chang Shi; Rashmi C. Desai; Jaan Noolandi

doi:10.1103/PhysRevLett.78.2577

Stability of Ordered Phases in Weakly Segregated Diblock Copolymer Systems

Mohamed Laradji, An-Chang Shi, Rashmi C. Desai, and Jaan Noolandi

Phys. Rev. Lett. 78, 2577 – Published 31 March 1997

Abstract

Stability of ordered phases in diblock copolymer melts is studied using a theory of anisotropic fluctuations, which bears a useful similarity with energy band theory in solids. We calculated stability lines of all ordered phases and found the hexagonally perforated lamellar phase to be unstable around the lamellar-cylindrical (LC) phase boundaries. We used fluctuation analysis to obtain dynamical pathways between ordered phases and argue that the observed modulated layered states along LC boundary regions are due to infinitely degenerate fluctuation modes of the lamellar phase.

Received 21 October 1996

DOI:https://doi.org/10.1103/PhysRevLett.78.2577

Authors & Affiliations

Mohamed Laradji¹, An-Chang Shi², Rashmi C. Desai¹, and Jaan Noolandi²

¹Department of Physics, University of Toronto, Toronto, Ontario, Canada M5S 1A7
²Xerox Research Center of Canada, 2660 Speakman Drive, Mississauga, Ontario, Canada L5K 2L1