This article is aimed at studying the evolution of H release as well as radiation-induced defects in polyethylene (PE), as a function of the irradiation dose under anoxic conditions. We analyze the influence of the energy transfers and trapping toward radiation-induced defects on the evolution of the radiation chemical yields with dose. One key objective herein is to quantify the contribution of these transfers toward trans-vinylene (TV) on H emission. For this purpose, pure PE was irradiated in a large dose domain and H emission was compared to that in predoped PEs containing chemically inserted TV groups irradiated at low doses. In parallel, evolutions of the concentrations of the TV groups and minor defects (vinyl and trans-trans-diene) as a function of dose were considered. Moreover, measuring simultaneously H and unsaturated groups had allowed inferring the cross-linking evolution with dose. With this methodology, we have succeeded in quantifying the efficiency of TVs and cross-links as energy traps and, using simple models, in fully describing the evolution of all of the radiation chemical yields. Besides, irradiations were performed using either low linear energy transfer irradiations (electron beams, γ rays) or ion beams, with the objective to assess the influence of the high ionization and excitation densities induced by the latter on PE ageing and energy transfer processes.
Two new coordination polymers, namely [Me3Sn(INA)] (CP1) and [Me3Sn(NA)] (CP2), where INA = isonicotinic acid and NA = nicotinic acid, were characterized using infrared, UV–visible and NMR spectroscopies, thermogravimetric analysis and single‐crystal X‐ray analyses. The structure of CP1 consists of a one‐dimensional coordinated chain which is further extended creating a two‐dimensional layer via hydrogen bonds. The two‐dimensional layers propagate along the corresponding planes creating a three‐dimensional framework by hydrogen bonding and edge‐to‐face π–π stacking. The asymmetric unit of CP2 contains one tin atom and one NA ligand exhibiting 1:1 stoichiometry. The structure of CP2 extends through coordination bonds to form a one‐dimensional zigzag chain which further extends to create a three‐dimensional network via crossing chains and hydrogen bonds. The tin atoms acquire distorted trigonal bipyramid (TBPY‐5) geometry. CP1 and CP2 were designed to investigate their cytotoxic properties against various human cancer cell lines: hepatocellular carcinoma, mammary gland breast cancer, human prostate cancer and colorectal carcinoma. The compounds are good anticancer agents against the tested cell lines. Also they were screened for their antioxidant, anti‐haemolytic, antibacterial and antifungal activities.
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