The authors have recently demonstrated the particular aptness of 13C as well as 1H Direct Polarization - Magic Angle Spinning (DP/MAS) NMR for the quantitative characterization of a chemically modified solvent-swollen polystyrene gel. The authors describe applications of DP/MAS NMR to the analysis of polystyrene gels, and focus on the crosslink junctions themselves. DP/MAS 13C and 1H NMR is shown to give high resolution spectra of functionalized solvent-swollen polystyrene gels. This permits routine analysis of chemically modified crosslinked polystyrenes, taking advantage of the high sensitivity in 1H, and of the fast, solution-like relaxation rates in 13C DP/MAS NMR. DP/MAS NMR would therefore be well suited to follow a reaction producing a gel-phase, for example measuring the kinetics of crosslinking polymerizations by NMR. Further, DP/MAS permits direct observation of the methyl groups in the crosslinker. This may allow access to the network dynamics of crosslinked polymer gels, by measuring the NMR relaxation rates of the crosslinks themselves.
|Number of pages
|American Chemical Society, Polymer Preprints, Division of Polymer Chemistry
|Published - Apr 1989
ASJC Scopus subject areas
- Polymers and Plastics