Abstract
A study was made on a preparative method for transmission electron microscopy (TEM) of poly(ethylene terephthalate) and poly(ethylene-2, 6-naphthalate). Osmium tetraoxide (OsO4) staining in its vapor phase at 75°C for 5 days is found to be a minimum requirement for a high image contrast of TEM between the crystalline and amorphous regions of the polymers in the stained ultrathin sections. This gives rise to an average crystallinity measured from the crystalline and amorphous thicknesses of the lamellae in a good coincidence with that estimated by density measurement.
