Poly(ethylene terephthalate). II. Electron microscopic studies

Electron micrographs were made from replicas taken from the natural, argon-etched, and fractured surfaces, respectively, of the polymer before and after progressive stages of crystallization. The natural surface protrusions were identified as axialities and became more defined as the crystallization progressed. The argon-etched surfaces of highly crystallized polymer did reveal the crystalline nature of the polymer, but replicas of the slightly crystalline material gave patterns which cannot be quantitatively described at this time. It is thought that heat effects and/or interactions with the argon ions had an effect on the polymer surfaces. Replicas of the fractured amorphous samples revealed a typical conchoidal fracture, whereas those of the fractured surfaces of the highly crystalline samples gave tangible evidence that this polymer crystallized in a characteristic spherulitic manner.