Observation of nanoparticles and film formation by scanning tunneling microscopy: methyl methacrylate/butyl methacrylate nanoparticles prepared by microemulsion polymerization

Kocum C., Zareie M., Ozer F., Piskin E.

COLLOID AND POLYMER SCIENCE, vol.278, no.6, pp.587-590, 2000 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 278 Issue: 6
  • Publication Date: 2000
  • Doi Number: 10.1007/s003960050560
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.587-590
  • Hacettepe University Affiliated: No


Latexes as dispersions of poly(methyl methacrylate-co-butyl methacrylate) copolymeric nanoparticles within water were produced by microemulsion polymerization of the respective comonomers. Polymer yield, number-average and weieht-average molecular weights, polydispersity index, and the glass-transition temperature of the copolymer produced were 50%, 8.8 x 10(4), 2.54 x 10(5), 2.8'7, and 45 degrees C. Scanning tunneling microscopy (STM) images of the latex nanoparticles and film formation on highly oriented pyrolitic graphite (HOPG) were obtained with a 2 V sample bias and a tunneling current of 20 pA. The STM pictures revealed that the particle size was 18 +/- 3 nm. There was no film formation in the case of dehydration at room temperature. There was some coalesence of particles when the HOPG surface was preheated at 55 degrees C, while complete film formation was achieved when the latexes were annealed at 55 degrees C in an oven for about 10 min.