Submicrometric characterization of the heterogeneous photooxidation of polypropylene by microthermal analysis

Evaluation of poly(ethylene terephthalate) photostabilisation using FTIR spectrometry of evolved carbon dioxide

“…Oxygen diffusionlimited reaction is caused when the oxygen from the atmosphere is consumed by rapid reaction near the illuminated surface before it can diffuse into the interior to react there. It is quite common in photo-oxidation of polymers and has been widely observed in polyolefins [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31]. However, oxygen starvation is expected to occur at even smaller depths in PET than in polyolefins because the diffusion coefficient for oxygen in PET is two orders of magnitude smaller than for PE [32].…”

Screening of polymer types and chemical weathering in macro- and meso-plastics found on lake and river beaches using a combined chemometric approach

“…67 Another paper also reported a maximum photo-oxidation depth of 250 μm after the artificial weathering of PP. 68 Thus, XPS is only able to collect a minor fraction of the chemical information available in a weathered polymer. Nevertheless, XPS gives invaluable information on the composition of the top surface (≈8–10 nm) of samples, which is seen as a good indicator of the direct solar exposition of the material and it has been often probed to understand how the UV-radiation affects the formation of functional groups in PP samples.…”

Environmental and Micro-Environmental Influences Affecting the Performance of Polymer Stabilisers

“…Characteristic depth profiles in relation to the buildup of carbonyl groups have been determined in LDPE samples exposed in a weatherometer Ci65 [14] . Timedependent profiles of carbonyl build-up have been studied together with the melting temperatures of PP plaques irradiated in a SEPAP 12.24 device [17] . Another investigation has concerned the influence of stabilization on the depth profile of M W changes in toughened-grade PP plaques subjected to UVA-340 exposure (Figure 1) [18] .…”