Abstract
Three sample preparation methods for the electron microscopy (EM) analysis of the morphology of polymeric materials were evaluated: (1) the ion-etching sample method, (2) the RuO4-staining method, and (3) the newly developed deeply etched section (DES) method. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analyses of samples prepared by these three methods revealed different aspects of the morphologies of the polymers. Ion etching was carried out in an AC glow discharge under low vacuum. The high-order structure of multiphase polymer systems and polymer-filler composites was clearly revealed through SEM analysis of ion-etched samples. The crystalline structure of RuO4- stained samples was observable through TEM analysis, because RuO4 selectively stained the amorphous chain. The three-dimensional morphological structure of the polymer was revealed by TEM analysis of stained ultra-thin sections of polymer samples prepared by the DES method. We believe these techniques will be useful in designing new morphologies in polymers as well as in revealing the higher order structure of polymers in general.