Solid‐State NMR Investigations of the Unusual Effects Resulting from the Nanoconfinement of Water within Amphiphilic Crosslinked Polymer Networks

Two types of solid‐state ¹⁹F NMR spectroscopy experiments are used to characterize phase‐separated hyperbranched fluoropolymer–poly(ethylene glycol) (HBFP–PEG) crosslinked networks. Mobile (soft) domains are detected in the HBFP phase by a rotor‐synchronized Hahn echo under magic‐angle spinning conditions, and rigid (hard) domains by a solid echo with no magic‐angle spinning. The mobility of chains is detected in the PEG phase by ¹H → ¹³C cross‐polarization transfers with ¹H spin‐lock filters with and without magic‐angle spinning. The interface between HBFP and PEG phases is detected by a third experiment, which utilized a ¹⁹F → ¹H–(spin diffusion)–¹H → ¹³C double transfer with ¹³C solid‐echo detection. The results of these experiments show that composition‐dependent PEG inclusions in the HBFP glass rigidify on hydration, consistent with an increase in macroscopic tensile strength.