TY  - JOUR
AU  - Auffarth, Sebastian
AU  - Wagner, Maximilian
AU  - Krieger, Anja
AU  - Fritsch, Birk
AU  - Hager, Linus
AU  - Hutzler, Andreas
AU  - Böhm, Thomas
AU  - Thiele, Simon
AU  - Kerres, Jochen
TI  - Nanophase-Separated Block-co-Polymers Based on Phosphonated Pentafluorostyrene and Octylstyrene for Proton-Exchange Membranes
JO  - ACS materials letters
VL  - 5
SN  - 2639-4979
CY  - Washington, DC
PB  - ACS Publications
M1  - FZJ-2023-02545
SP  - 2039 - 2046
PY  - 2023
AB  - Nanophase separation into hydrophobic and hydrophilic domains in commercial perfluorosulfonic acid polymers promotes high conductivity by forming proton-conductive channels within a matrix. To transfer this beneficial phase separation to phosphonic acid functionalized ionomers, we combine phosphonated polypentafluorostyrene and flexible polyoctylstyrene in a di-block-co-polymer. We introduce a stepwise approach, including mesophase simulations, synthesis, and spectroscopic imaging. After the required block lengths were calculated, controlled radical polymerization led to a narrowly distributed block-co-polymer. The respective block-co-polymer membrane outperforms a phosphonated pentafluorostyrene blend concerning conductivity and water uptake. Stained membrane cross-sections revealed bicontinuous nanophase separation in the 13 to 25 nm range in transmission electron microscopy. The ion-conducting phosphonated polymer block assembled into an isotropic, three-dimensional gyroidal network across the membrane. Our stepwise approach is transferable toward other block-co-polymer systems featuring different monomers or functional groups. Applying the proposed principles allows for the prediction of structure-related phase separation while reducing the amount of synthesis work.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:001016545300001
DO  - DOI:10.1021/acsmaterialslett.3c00569
UR  - https://juser.fz-juelich.de/record/1008906
ER  -