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ABSTRACT
The polyimide films PM-A were investigated by X-ray diffractometry after deformation at temperatures of liquid nitrogen and liquid helium. As a result of deformation the temperature of liquid nitrogen in the films two regions with different densities were formed. It was found that the deformation of films at liquid-helium temperatures, does not lead to significant changes in the structure of the film. Assuming that the film consists of quasi-linear chain molecules, two «mechanism» has been proposed. These «mechanisms» are qualitatively describe the processes taking place in the polyimide films PM-A after deformation at low temperatures.