A nanoscopic view of structure and deformation of hard elastic polypropylene with scanning force microscopy

Microscopic deformation behavior of hard elastic polypropylene during cold-stretching process in fabrication of microporous membrane as revealed by synchrotron X-ray scattering

“…In Stage II, the profiles with the intense scattering due to the formation of voids are observed, with showing a shoulder peak. It is hard to estimate the shape, the size and its distribution of the voids by fitting the profile with a theoretical equation, because the profiles would include the scattering intensity from the lamellar structure and the excess scattering at the lower scattering vector, which should be originated from a larger 'crack' formed between lamellae [17]; still there is no doubt about that the voids has a size comparable to the long period with a narrow distribution of the size. In the M A N U S C R I P T…”

Structural Evolution of Hard-Elastic Isotactic Polypropylene Film during Uniaxial Tensile Deformation: The Effect of Temperature

“…With in-situ atomic force measurements, early studies indeed reported the occurrence of cavitation. 91 However, as cavitation is a passive energy consuming process rather than a spontaneous phase transition, if cavitation occurred in interlamellar amorphous it could only lead to a maximum microstrain ε m equal to macrostrain ε, which is contradictory to the experimental results. As shown in Figures 5, 8, and 14, the increment of ε m in zone B can reach nearly 3 times larger than that of the corresponding ε.…”

“…(ii) As strong lozenge scattering emerges close to beamstop when strain entering the nonlinear deformation zone B, cavitation of amorphous area might be one possibility to trigger yield. With in-situ atomic force measurements, early studies indeed reported the occurrence of cavitation . However, as cavitation is a passive energy consuming process rather than a spontaneous phase transition, if cavitation occurred in interlamellar amorphous it could only lead to a maximum microstrain ε m equal to macrostrain ε, which is contradictory to the experimental results.…”

Evolution of the Nanoporous Structure of High-Density Polyethylene during Drawing in Supercritical Carbon Dioxide

“…This method has been earlier successfully used in the study of the development of the structure of polymer materials during the uniaxial deformation in liquid AAM 24 and for hard elastics. 55 Figure 11 shows the AFM images of the HDPE film surface after its drawing in the SC-CO 2 along the machine direction to different relative elongations. It is to be seen that the morphology of the deformed polymer surface was significantly changed in comparison with the initial film (Figure 3) or the film drawn in air at pressure of 0.1 MPa (Figure 5).…”

“…In this study, the structural changes accompanying the uniaxial deformation of the HDPE films in the SC-CO 2 were visualized by means of AFM. This method has been earlier successfully used in the study of the development of the structure of polymer materials during the uniaxial deformation in liquid AAM and for hard elastics Figure shows the AFM images of the HDPE film surface after its drawing in the SC-CO 2 along the machine direction to different relative elongations.…”