Contribution of the methine proton to the transverse 1H NMR relaxation in vulcanized natural rubber

C. A. STEREN; G. A., MONTI; A. J. MARZOCCA; S. CERVENY

MACROMOLECULES

Año: 2004 vol. 37 p. 5624 - 5624

0024-9297

font face="Times New Roman" size="1"> Transverse 1H NMR relaxation experiments in vulcanized Natural Rubber (NR) samples above the glass transition temperature (Tg) are reported on. Natural Rubber samples with the same  initial chemical composition but different times of cure were studied. The distinct feature of this study as compared to previous works, is that the contribution to the total transverse 1H magnetization of the methine group of the monomeric unit and, the contribution of the methyl and methylene functional groups are analyzed independently. The results of these experiments show that for short delay times the decay of the 1H transverse magnetization of the methine groups is slower than that of the methyl/methylene groups. Consequently, the methine 1