Tapping mode AFM evidence for an amorphous reticular phase in a condensation-cured hybrid elastomer: α,ω- dihydroxypoly(dimethylsiloxane)/poly(diethoxysiloxane)/fumed silica nanoparticles
A new surface phenomenon is reported for hybrid nanocomposites comprising (1) a low Tg poly(dimethylsiloxane) (PDMS) phase cross-linked by (2) a siliceous phase (SP) generated by in situ hydrolysis/condensation of poly(diethoxysiloxane) (PDES), and (3) fumed silica nanoparticles (FSN). After ambient temperature cure, tapping mode atomic force microscopy (TM-AFM) easily reveals near-surface FSN. For nanocomposites with higher PDES content, FSN surprisingly "disappear" after a further cure at 100 °C. The observation is explained by further condensation of extant siliceous fragments creating an amorphous reticular phase, which acts as a mechanical barrier between the FSN and the AFM tip. Copyright © 2004 American Chemical Society.
Journal of the American Chemical Society
Ogoshi, T., Fujiwara, T., Bertolucci, M., Galli, G., Chiellini, E., Chujo, Y., & Wynne, K. (2004). Tapping mode AFM evidence for an amorphous reticular phase in a condensation-cured hybrid elastomer: α,ω- dihydroxypoly(dimethylsiloxane)/poly(diethoxysiloxane)/fumed silica nanoparticles. Journal of the American Chemical Society, 126 (39), 12284-12285. https://doi.org/10.1021/ja0474345