Visualization of single-chain conformations of a synthetic polymer with atomic force microscopy

The conformational characteristics of linear macromolecules are one of the most important physical factors for an interpretation and understanding of their properties. It would be extremely stimulating for new insights into polymer behavior if we could directly observe a single-chain conformation of macromolecules with microscopy. We report here our experimental result that the random coil conformations of single synthetic polymer molecules frozen on a substrate were successfully identified for the first time. In conclusion, we have developed a method to observe individual polymer chains on a two-dimensional surface by AFM. In this report we used PS-b-PMMA as model polymer to identify the single molecules.It is probably not necessary to use block copolymers; the technique should be applicable to a wide variety of polymers which are known to spread as monolayers on the water surface.