Nuclear magnetic relaxation studies of poly(p-phenylene sulphide) doped with sulphur trioxide

Molecular dynamics of poly(ethylene terephthalate)/poly(phenylene sulfide) nanocomposites with barium titanate

“…In order to propose the model of internal dynamics, the spin-lattice relaxation time and the second moment of the 1 H NMR line were calculated in terms of the dipole-dipole BPP theory [13]. Taking into account the fact that time relaxation T 1 are temperature independent on the low temperature side it is suggested for all samples the existence of paramagnetic relaxation [14]. It is assumed that the temperature dependence of T 1 in nanocomposites is governed by dipolar interaction modulated by a specific motion of the phenylene ring of PET and PPS (possible flipping), a slow motion that is unique to the ethylene groups of PET (probably due to the trans-gauche isomerization) and an almost effectively isotropic reorientation of some amorphous polymer segments of PET and PPS in higher temperatures [15] and moreover by the paramagnetic relaxation.…”

Proton longitudinal NMR relaxation of poly(p-phenylene sulfide) in the laboratory and the rotating frames reference

“…The purification (degassing and extraction) changes character of magnetization recovery curves in the T 1 experiment. In this case recovery of magnetization becomes non-exponential [8]. Therefore the aim of this study is to explain this discrepancy using the T 1r off in the rotating frame off-resonance technique [9].…”