Preparation of polymeric nanoparticles and observation on the structure ofnovel nanosized physical hydrogels by AFM and SEM methods

A series of novel nano-sized physical hydrogels based on the hydrophobic po lymeric nanoparticles have been prepared via a modified microemulsion polym erization, which may contain as much as above 90% water with nanosized part icle diameter of about 20 nm, The specific structures of the prepared hydro gels were observed successfully by Atomic Force Microscope (AFM) and Scanni ng Electron Microscope(SEM), The micrographs showed that the polymeric nano particles and their aggregated clusters were connected to form the networks of hydrogels, in which water including free water and bound water were emb edded. The formation mechanism of the hydrogel has also been discussed in t his paper.