Improved Structural Elucidation of Synthetic Polymers by Dynamic Nuclear Polarization Solid-State NMR Spectroscopy

International audienceDynamic nuclear polarization (DNP) is shownto greatly improve the solid-state nuclear magnetic resonance(SSNMR) analysis of synthetic polymers by allowing structuralassignment of intrinsically diluted NMR signals, which aretypically not detected in conventional SSNMR. Specifically,SSNMR and DNP SSNMR were comparatively used to studyfunctional polymers for which precise structural elucidation ofchain ends is essential to control their reactivity and toeventually obtain advanced polymeric materials of complexarchitecture. Results show that the polymer chain-end signals,while hardly observable in conventional SSNMR, could be clearly identified in the DNP SSNMR spectrum owing to the increasein sensitivity afforded by the DNP setup (a factor ∼10 was achieved here), hence providing access to detailed structuralcharacterization within realistic experimental times. This sizable gain in sensitivity opens new avenues for the characterization of“smart” functional polymeric materials and new analytical perspectives in polymer science