AFM IMAGING AND CHARACTERIZATION OF LATEX-PARTICLES FORMED BY COPOLYMERIZATION OF STYRENE AND POLY(ETHYLENE OXIDE) MACROMONOMER

A new type of latex particle was prepared by copolymerization of styre ne and poly(ethylene oxide) macromonomer. By controlling the concentra tion of styrene in reaction mixtures, several latexes with different g rain sizes were obtained. The packing patterns of the latex films as w ell as shapes and sizes of the latex particles were measured with atom ic force microscopy (AFM). AFM images revealed that the grain sizes of the latexes increase with increasing concentration of styrene. At a h igher styrene concentration (10 wt%), the latex showed a rather homoge nous distribution of grain sizes. Lateral force microscopy (LFM) was u sed to reveal frictional features of latex particles. Contact and non- contact mode AFM were employed to image the same sample of the latex f ilms. The results show that AFM working in non-contact mode can be use d to effectively eliminate the horizontal-line-like artifacts, which m ay obscure AFM images. (C) 1998 Elsevier Science B.V.