High-resolution TEM imaging of polymer crystals using 2D-class averaging methods

High-resolution imaging of polymer crystals has so far been a challenge for transmission electron microscopy because of their high sensitivity to radiation. However, with the development of new camera systems, it is now possible to push the dose-limited resolution limit far enough to directly image previously inaccessible systems. Using the example of solution-grown polyethylene single crystals, we demonstrate how HR imaging can be achieved despite a low critical electron dose in conjunction with a small lattice spacing and how imaging can be further improved with the aid of methods from single particle analysis and subsampling image reconstruction. • State-of-the-art cryo-EM enables HR imaging of beam-sensitive polymer crystals. • HR pattern of polyethylene and isotactic polystyrene crystals is presented. • Polymer lethal dose determines the maximum achievable resolution. • 2D classification averaging and AI sparse sampling can further increase resolution.