Water-based strippable coatings containing bentonite clay for heavy metal surface decontamination

In this paper, a novel approach for water-based strippable coatings for surface decontamination is reported. The novelty of this work consists in the development of a new method of removing heavy metals from contaminated surfaces by using polyvinyl alcohol strippable coatings containing bentonite clay. Viscosity measurements, evaporation rate tests, thermal analyses, FT-IR and tensile tests were performed for the optimization of the decontamination solution composition. For the decontamination experiments, copper surfaces were contaminated with mercury and, further, the decontamination water solutions containing polyvinyl alcohol, glycerol, EDTA and bentonite were applied onto these surfaces. After the removal of the polymer films, the copper coupons were subjected to SEM–EDX analysis, which revealed that introduction of bentonite in the polymer solution leads to a significant increase of the decontamination factor

Chemical structure of methylmethacrylate-2-[2′,3′,5′-triiodobenzoyl]oxoethyl methacrylate copolymer, radio-opacity, in vitro and in vivo biocompatibility

The properties of copolymers (physical, chemical, biocompatibility, etc.) depend on their chemical structure and microstructural characteristics. We have prepared radio-opaque polymers based on the copolymers of methyl methacrylate (MMA) and 2-[2′,3′,5′-triiodobenzoyl]oxoethyl methacrylate (TIBOM). The copolymerization reaction between TIBOM and MMA showed that the reactivity ratios were r1 = 0.00029 and r2 = 1.2146. The composition diagram is typical for a practically non-homopolymerizable monomer (TIBOM) and a very reactive monomer (MMA). The copolymers were analyzed on an X-ray microcomputed tomograph and they proved to be radio-opaque even at low concentrations of TIBOM. The biocompatibility was tested both in vitro (with J774.2 macrophage and SaOS-2 osteoblast like cells) and in vivo in the rat. These materials were found to be non-toxic and were well tolerated by the organism. These combined results led to the suggestion that this type of polymer could be used as dental or bone cements in place of barium or zirconium particles, which are usually added to provide X-ray opacity

Environmental Long Term Impact on a Romanian Military Testing Range

Military range management has become extremely important in recent years, in order to comply with the limitations imposed by national and international environmental regulations. In this regard, soil, vegetation and ground water samples from a testing facility belonging to the Romanian Ministry of National Defense were analyzed for contamination with metals and energetic materials. The tests confirmed the presence of contaminants as energetic materials and heavy metals (Pb, Cu, Zn), with a heterogeneous distribution on the range and concentrated in the impact and firing line areas