This work aimed to research the efficiency of gamma irradiation and shielding characteristics on the lead oxide (PbO) doped the crosslinked polystyrene-b-polyethyleneglycol (PS-b-PEG) block copolymers and polystyrene-b-polyethyleneglycol-boron nitride (PS-b-PEG-BN) nanocomposites materials. The crosslinked PS-b-PEG block copolymers and PS-b-PEG-BN nanocomposites mixed with different percentage rates of PbO were used to research gamma-ray shielding characteristics. The synthesis of the copolymer was done by emulsion polymerization methods. The characterization and morphological analyses of irradiated samples were explored handling with the Nuclear Magnetic Resonance (NMR), Fourier Transform Infrared Spectroscopy (FTIR), Gel Permeation Chromatography (GPC), Thermogravimetric Analysis (TGA), and Scanning Electron Microscope (SEM) methods. The gamma-rays that were emitted from the E 152u source were observed with a High Purity Germanium (HPGe) detector system and examined with a GammaVision computer program. Our samples, including the different percentage rates of the PS-b-PEG (1000, 1500, 10,000), BN, and PbO, were irradiated in various gamma-ray photon energy regions (from 121.78 keV to 1408.01 keV). Then, Linear-Mass Attenuation Coefficients (LACs-MACs), Half-Tenth Value Layer (HVL), Mean Free Path (MFP), and Radiation Protection Efficiency (RPE) values of the samples were calculated. Via crosschecking the acquired data from samples with and without PbO and BN, it was observed that, if the different percentage rates by weight nano-powder of PbO and BN are added in the polymer mixture, it can be used as a convenient shielding material against gamma rays.

Summary The work which has been done on cement‐polymer composite based shielding materials was comprehensively described in the present article, the choice of the study presented here is based on the choice of the researches. The new Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane Plaster‐concrete composites mixed with different percentage soft lead oxide and arsenic oxide is used to research gamma‐ray shielding and thermal conductivity characteristics. The synthesis of new Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane copolymer was achieved by Atom Transfer Reaction and Condensation Polymerization methods. The characterization of Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane Plaster was made with the Nuclear Magnetic Resonance, Fourier Transform Infrared Spectroscopy, Differential Scanning Calorimetry, Gel Permeation Chromatography, Thermogravimetric Analysis, Scanning Electron Microscope methods. The transmitted fluxes of gamma‐rays that were emitted from Eu152 source was detected by a High Purity Germanium (HPGe) detector system at Karadeniz Technical University‐Department of Physics in Trabzon and analyzed by a GammaVision (Version:6.07‐Ortec, Oak Ridge, TN) computer program. The composite phase change materials including 89, 87, 69, 67% Portland cement, 1% and 3% PU‐Plaster, 10% and 30% weight percent lead oxide and arsenic oxide was irradiated in the various gamma ray photon energy region (121.78, 344.28, 778.90, 964.08, 1085.87, 1112.07, and 1408.01 keV) for 3600 seconds. Then, linear attenuation coefficients, mass attenuation coefficients, half‐value layer, tenth value layer, mean free path, radiation protection efficiency, and gamma‐rays absorption of concrete‐the Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane copolymers specimens were experimentally investigated. Thermal properties and morphological analysis of the irradiated substances were explored handling differential scanning calorimetry, thermogravimetric analysis, and scanning electron microscope methods of the nano lead oxide and arsenic oxide including composite phase change material via gamma irradiation were submitted. Moreover, the effect of the Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane amount on the radiation attenuation of the composite material was investigated. Gamma attenuation experiments have been performed to specify lead equivalent values for the improved composite material. The composite equivalent thickness values from 0.5 to 0.6 cm sample thickness and 0.665 cm radius were obtained. Via crosschecking the acquired data from concrete samples with and without lead and arsenic, it was observed that, if the powder of lead oxide and arsenic oxide to cement ratio of 10% and 30% by weight is added in the concrete mixture, the concrete‐the Hyperbranched Poly Amino‐Ester‐block‐Poly Caprolactone‐Polyurathane composite can be used as a suitable shield against gamma rays. Also, mass attenuation coefficients were calculated as theoret...

Thioxanthone–anthracene‐9‐carboxylic acid (TX‐ANCA) namely 14‐oxo‐14H‐naphthol [2,3‐b]thioxanten‐12‐carboxylic acid, is synthesized and characterized as part of our continuing interest for syntheses of polyaromatic initiators. Photoinitiator, TX‐ANCA have good absorption properties in the UV and visible region of the electromagnetic spectrum (ɛ370: 9080 M−1cm−1, ɛ430: 6151 M−1 cm−1). The fluorescence quantum yield is calculated as 0.1 which is slightly higher than of the parent thioxanthone compound (φf: 0.07). The phosphorescence lifetime is found to be 39 ms. The possible initiating mechanism of TX‐ANCA is based on photoexcitation of TX‐ANCA and quenching of triplet excited states of TX‐ANCA by molecular oxygen generates singlet oxygen. Singlet oxygen reacts with the anthracene moiety of TX‐ANCA possibly forms an endoperoxide. The endoperoxides undergoes photochemical or thermal decomposition to form radicals which are able to initiate free radical polymerization. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 1878–1883

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