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Modifying Frank–Kasper Mesophases by Modulating Chain Configuration in PDMS- b -PTFEA Copolymers

Jeon, Seungbae·Jun, Taesuk·Jo, Seungyun·Kim, Kyungkon·Lee, Byeongdu·Lee, Sangwoo·Ryu, Du Yeol
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Abstract

The common spherical mesophases observed from chemically distinct compounds have promoted extensive studies of packing structures in soft-matter self-assemblies. In this report we present a new approach for controlling sphere-packing phases by modulating homologous copolymer chain configurations. To this end, three sets of sample pairs, compositionally asymmetric polydimethylsiloxane-b-poly(2,2,2-trifluoroethyl acrylate) (PDMS-b-PTFEA) diblock copolymers (diBCPs) and their homologues containing the corresponding triblock copolymer (triBCP), are synthesized via atom transfer radical polymerization and designed with the consistent volume fractions of the core-forming PTFEA block, f PTFEA = 0.20, 0.18, and 0.15. We identify the formation of C15 and hexagonally close-packed (HCP) phases in the triBCP-containing PDMS-b-PTFEAs, whereas the sigma and C14 phases are formed in their diBCP analogues, respectively. These phase shifts into C15 and HCP, due to molecular configuration differences, reveal a significant yet unrealized role of chain configurations and the associated chain size effects in determining the stable sphere-packing phases in BCP systems.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY59 BASIC BIOLOGICAL SCIENCESFrank-Kasper phasesblock copolymer self-assemblycopolymer configurationsphere-packing

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Jeon, Seungbae, Jun, Taesuk, Jo, Seungyun, Kim, Kyungkon, Lee, Byeongdu, Lee, Sangwoo, Ryu, Du Yeol. 2022-09-08. Modifying Frank–Kasper Mesophases by Modulating Chain Configuration in PDMS- b -PTFEA Copolymers. https://doi.org/10.1021/acs.macromol.2c01146

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