Observation of latent ion tracks in semicrystalline polymers by scanning electron microscopy

Abstract

Advances in nanotechnology and materials science require further improvement of metrology of nanostructured polymers, in particular, polymers modified by high energy ion beams. The observation of latent ion tracks using various microscopy methods is an important part of studies on heavy ion effects in solids. However, scanning electron microscopy (SEM) has not been utilized for polymers. In the present study, it is shown how SEM can be used to observe latent tracks in semicrystalline polymers. The procedure includes the embrittlement of a polymer specimen by controlled photooxidation and its subsequent fracture. Latent tracks are clearly visible on fractured surfaces as structureless stripes surrounded by an inhomogeneous semicrystalline matrix. Using this method, the latent tracks of Kr, Xe, Au, and Bi ions with energies of 1-11 MeV/u in polyethylene terephthalate and polypropylene films are observed and their diameters are estimated. In contrast to transmission electron microscopy, the suggested novel technique detects the outer track shell consisting of an amorphized polymer. Therefore, SEM observations can complement other commonly used techniques to comprehensively characterize the structure of ion tracks in polymers.

Overview of Polyethylene Terephthalate Foils Patterned Using 10 MeV Carbon Ions for Realization of Micromembranes

“…Further benefits are ascribable to the good membrane reproducibility and the customized pore locations suitable for microfluidics and organ-on-chip applications. In addition, since the pore geometry, size and shape strongly influence the membrane properties, the complex damage structure [ 16 ] in the ion tracks, which can give insights into the pore size, shape, and connectivity, has been determined by the combination of Scanning Transmission ion Microscopy [ 15 ] and the TrackHH code created in our laboratory.…”

Insight into What Is inside Swift Heavy Ion Latent Tracks in PET Film

“…According to the swift electron model, electrons move out of the central part of the latent track, leaving it positively charged, taking the ion energy with them into their interactions with the molecular structure of the polymer in the track shell. Many studies of these interactions [9][10][11][12][13][14] focus solely on the energy transfer from the swift electrons that leads to radiation cross-linking of polymer chain molecules in the track shell, with no consideration of the negative electron charge transfer from the center of the track to its periphery.…”

Fragmentation Pattern and Removal Mechanism of Concrete Subjected to Abrasive Water Jet Impact

“…By the SEM technology, Fan et al [23] evaluated the thermal effects on the geophysical properties of granite. Blonskaya et al [24] observed the latent ion tracks in semicrystalline polymers by scanning electron microscopy. Zhao et al [25] revealed the micromechanism of the effect of strain rates on rock mechanical behaviors.…”