Abstract: Proton spin-lattice relaxation times are reported for a 30% polyesterpolyurethane zwitterionomer solution. Measurements of spin-lattice relaxation time as a function of temperature are included. The correlation times of molecular reorientation were calculated with the isotropic model according to BPP theory. The proton spin-lattice relaxation time of polyesterpolyurethane is dominated by dipole-dipole interaction. The molecular reorientations are not at the same time scale between the hard and the soft segments. The molecular reorientation of the soft segments is much faster than that of the hard segment. Strong hydrogen bonds in the hard segments make molecular reorientations of the hard segment groups to have close correlation times. The interactions between the hard and the soft segments in polyesterpolyurethane can also be investigated by comparison of the correlation times in temperature range studied and by comparison of apparent activation energies of four NH peaks.

Key words: Dynamics, Nuclear magnetic resonance, Polyesterpolyurethane, Spin-lattice relaxation time, Polyurethane