SURFACE OF LATEX FILMS IMAGED BY ATOMIC-FORCE MICROSCOPY

Atomic force microscopy (AFM) has been used to image latex film surfac es in the standard contact mode (CM) and in the tapping mode (TM). The TM gives sharper images than the CM, but particle shapes have been ob served with the TM which closely resemble to shapes predicted or descr ibed in the literature and which were artifacts due to damaged tips. C omparison between AFM and scanning electron microscope images of close d-packed latex particles, indicate that the hexagonal contour of the p articles seen by AFM can be real, and is not simply due to the triangu lar or conical shape of the tip. Finally, particles coming from two di fferent synthesis are shown. The one gave latex particles very monodis perse in size, and the other gave two populations of latex particles c learly seen by AFM. The smallest particles of the second synthesis cou ld not be evidenced by quasielastic light scattering (QELS). Therefore , with QELS the second latex appeared monodisperse in size. This shows the advantage of AFM over QELS.