The influence of the neutralizing cation on the response of model polyurethane ionomers to uniaxial extension is investigated by small-angle X-ray scattering. Anisotropic scattering patterns are observed for ionomers neutralized with Na+, Sr 2 + and Ca 2 + upon elongation, with the precise nature of the response depending on the neutralizing cation. Scattering patterns of elongated ionomers neutralized with Ni 2 + and Cd 2+ display little or no anisotropy up to extension ratios of 2 = 5.0 and 3.0, respectively. A model invoking ionic aggregate spatial rearrangement within the polymer matrix and removal of ionic groups from the aggregates to the polymer matrix or to other aggregates is postulated to explain the results.
Посилання на статтю:
Small-angle X-ray scattering investigation of ionomer deformation: effect of neutralizing cation / Susan A. Visser* and Stuart L. Cooper // Polymer. – 1992. – Vol 33. – P. 4705-4710.