In situ structural characterization of semi-crystalline polymer latex particles by small-angle X-ray scattering

摘要

The inner structure of polyurethane latex particles has been studied in situ using small-angle X-ray scattering (SAXS). From contrast variation SAXS measurements evidence could be given that the dispersed particles are semi-crystalline. The semi-crystalline structure gives a strong contribution to the measured intensities in an intermediate range of scattering vectors. This contribution, which is independent of the adjusted contrast, could be separated and the long period of the lamellar structure could thus be determined quantitatively to 11 nm. In addition, it was found that the particles exhibit a core-shell structure which arises from electron-rich acid groups that are preferentially located at the particle surface.