SOLID-STATE NMR-STUDY OF NATURAL-RUBBER BLENDED WITH EVA AND EVA MODIFIED WITH MERCAPTOACETIC ACID

Solid-state C-13 NMR spectroscopy involving magic angle spinning (MAS) techniques with and without cross-polarization was employed for inter action studies in natural rubber (NR)/EVA and NR/mercapto-modified EVA (EVASH) blends. From arrayed of variable contact time spectra, the pr oton T-1 rho values were determined at short contact times to analyze the EVA or EVASH domains and longer contact times to investigate the i nteractions in the NR domains. Substantial changes have been observed when dicumyl peroxide was employed as curing agent in NR/EVASH and NR/ EVA/EVASH blends.