Latex State and Solid-State NMR Spectroscopy of Elastomers

Latex state NMR spectroscopy and field gradient fast magic angle spinning solid-state NMR spectroscopy were utilized for structural characterization of rubbery polymers and crosslinked rubbery materials. High resolution NMR spectra for elastomers were achieved either through Brownian motion of a latex dispersion or fast magic angle spinning for a solid. Sequence distribution of cis-1,4-, trans-1,4- and 1,2-butadiene units was investigated for polybutadiene through latex state NMR spectroscopy because the polybutadiene used in this work was prepared by emulsion polymerization. Crosslinking junctions of vulcanized natural rubber were analyzed by field gradient fast magic angle spinning solid-state NMR spectroscopy. The vulcanized natural rubber with quaternary carbons linking to sulfur as the crosslinking junction was found to be superior in mechanical properties compared to the rubber samples with tertiary carbons linking to sulfur.