title: Small-angle X-ray scattering study on poly(ethyl acrylate-co-itaconate) ionomers neutralized with various cations.
abstract: The morphology of poly(ethyl acrylate-co-itaconate) ionomers neutralized partly and fully with Na(I), Li(I) and Zn(II) was studied using a small-angle X-ray scattering (SAXS) technique. It was found that the SAXS peak position for the ionomers shifted to lower angle with increasing degree of neutralization for the ionomers containing 5.8 mol% of ionic repeat units. In the case of 11.9 mol% ionomers, with increasing degree of neutralization from 50% to 100% the SAXS peak shifted to slightly higher angles. With the density data and the space-filling concept for a simple cubic lattice, the average radii of multiplets of the ionomers were calculated. For 5.8 mol% ionomers, the radius of the Li-ionomer increased from 0.35 nm to 0.43 nm with increasing neutralization degree from 50% to 100%, and that of the Na-ionomer changed from 0.34 to 0.53 nm. In the case of the 11.9 mol% ionomers, the radius changed from 0.51 to 0.49 nm for the Li-ionomer and from 0.42 nm to 0.47 nm for the Na-ionomer. For the Zn-ionomers, only 100% neutralized ionomers showed a SAXS peak. From the SAXS profiles, the persistence lengths of the polymer chains attached to the scattering centers were also obtained.
authors.affiliation: Department of Polymer Science and Engineering and BK21 Education Center of Mould Technology for Advanced Materials and Parts, Chosun University, Gwangju 501-600, Korea.
authors.forename: Ju-Myung
authors.initials: JM
authors.lastname: Song
authors.forename: Joon-Seop
authors.initials: JS
authors.lastname: Kim