| Abstract: | A special technique was used for investigating polymers in the electron microscope at essentially reduced radiation damage. The method is based on a high voltage electron microscope (accelerating voltage of 1 MV) and the use of highly sensitive X-ray films. Compared with the conventional transmission electron microscopy this technique reduces the specimen damage by a factor of 50 … 100. Diffraction contrast can therefore be used to investigate the structure of semi-crystalline polymers. Using samples of polyethylene, the arrangement of the lamellae was determined by bright field and dark field images and diffraction patterns. There are further advantages concerning the improved possibility of investigating very thick specimens (thicknesses above 5 μm). Thus, a better stereoscopic analysis of extended structures is possible, and in-situ deformation tests of polymers can be performed in the electron microscope. |
