Dynamic nuclear polarization (DNP) solid-state NMR was used to obtain natural abundance 13C and 15N CP MAS NMR spectra of microporous organic polymers with excellent signal to noise ratio, allowing for unprecedented details in the molecular structure to be determined for these complex polymer networks. Sensitivity enhancements larger than 10 were obtained with bis-nitroxide radical at 14.1 T and at low temperature (~105 K). This DNP MAS NMR approach allows efficient, high throughput characterization of libraries of porous polymers prepared by combinatorial chemistry methods.

see for example:

Dynamic Nuclear Polarization NMR Spectroscopy Allows High Throughput Characterization of Microporous Organic Polymers, F. Blanc, S. Y. Chong, T. O. McDonald, D. J. Adams, S. Pawsey, M. A. Caporini, A. I. Cooper, J. Am. Chem. Soc. 2013, 135, 15290-15293

Swellable, Water- and Acid-Tolerant Polymer Sponges for Chemoselective Carbon Dioxide Capture, R. T. Woodward, L. A. Stevens, R. Dawson, M. Vijayaraghavan, T. Hasell, I. P. Silverwood, A. V. Ewing, T. Ratvijitvech, J. D. Exley, S. Y. Chong, F. Blanc, D. J. Adams, S. G. Kazarian, C. E. Snape, T. C. Drage, A. I. Cooper, J. Am. Chem. Soc. 2014, 136, 9028-9035

Structure Elucidation of Amorphous Photocatalytic Polymers from Dynamic Nuclear Polarization Enhance Solid State NMR, N. J. Brownbill, R. S. Sprick, B. Bonillo, S. Pawsey, F. Aussenac, A. J. Fielding, A. I. Cooper, F. Blanc, Macromolecules 2018, 51, 3088-3096

13C CP solid state NMR spectra of libraries of polymers could be obtained very quickly with Dynamic Nuclear Polarization