The Staining of Polymers II

Abstract

E.H. Andrews [1] was the first to produce transmission electron micrographs that differentiated between crystalline and amorphous forms in long chain polymers. Working with thin cast films of cis-polyisoprene {natural rubber (NR)}; he examined them in the unstrained and strained states. Staining the unstrained thin films with osmium tetroxide vapors, he showed that spherulitic crystals were in light contrast whereas the darker contrasted matrix was the amorphous continuum (Figure 1).