The field-induced surface polymerization of styrene

Polymerization of monomers usually occurs by using suitable initiators and/or catalysts under different physical conditions. Now we have found that a nanometer-scale polystyrene film can be generated directly from liquid styrene film on graphite substrate, in air at room temperature. The polymerization procedure is initiated from an intense electric field provided by the tip of a scanning tunneling microscope. The analytical result obtained by time-of-flight type secondary-ion mass spectrometry has verified the yield. Further investigation showed that, after a sustained scanning of the field, the surface structure of the polystyrene turned itself into a highly ordered reconstruction configuration.