Correlation between relief formation and structural rearrangements during annealing of oriented amorphous polymers with metallic coating

Visualization of structural rearrangements during annealing of solvent-crazed isotactic polypropylene

“…Second, the thermomechanical behavior of the solvent crazed polymer is strongly controlled by its initial crystalline structure. Third, in contrast to solvent crazed amorphous polymers [7], PP is unable to attain complete strain recovery even at high annealing temperatures.…”

“…In recent years, a new microscopic pro cedure has been proposed [1][2][3][4]; the use of this proce dure makes it possible to gain direct information on the above structural rearrangements and offers new knowledge concerning the deformation mechanism of amorphous polymers at temperatures below [5] and the above glass transition temperature [6]. In particu lar, annealing of PET samples oriented above the glass transition temperature was accompanied by both shrinkage and elongation along the direction of pre liminary tensile drawing, the so called phenomenon of spontaneous self elongation [6,7]. In this case, after annealing, the resultant length of the sample is smaller as compared with its initial length, but the use of the above microscopic procedure allows a direct and vivid visualization of the spontaneous self elongation of PET under the above conditions [1][2][3][4].…”