Abstract: Polystyrene microparticles prepared by microemulsion free-radical polymerization,have been found to be much different from ordinary polystyrene,but their structures still remain unknown,Therefore we use the scanning tunneling microscope (STM) to investigate them.It is found that at least in some regions of the polystyrene surface,the polymer chains are orderly stacked without entanglement.It is also found that the oagulation of polymer chains can be varied with different regions.The existence of the orderely-stacked polymer chains might be the reason why the polystyrene microparticles have different properties from the ordinary atactic polystyrene.

Key words: Polystyrene microparticles, Polymer chain segments, Coagulation, Scanning tunneling microscope