Physical electron beam treatment

Some physical techniques can be classified into flame treatments, corona treatments, cold plasma treatments, ultraviolet (UV) treatment, laser treatments, x-ray treatments, electron-beam treatments, ion-beam treatments, and metallization and sputtering, in which corona, plasma, and laser treatments are the most commonly used methods to modify silicone polymers. In the presence of oxygen, high-energy-photon treatment induces the formation of radical sites at surfaces these sites then react with atmospheric oxygen forming oxygenated functions. 

The thioether alone at room temperature does not protect polypropylene from loss of physical properties after electron-beam treatment, although irradiated samples that are subsequently heated to 150°C are apparently protected from thermal oxidation. 

Kawamura K. and V. H. Shui, 1984. Pilot Plant Experience in Electron-Beam Treatment of Iron-Ore Sintering Flue Gas and Its Application to Coal Boiler Flue Gas Gleanup. Physical Ghemistry, 24(1) 117-127. 

Martin, D., Cracinn, G., ManaUa, E., Ighigeanu, D., Togoe, I., Oproiu, C., Margaritescn, I., and lacob, N. 2006. Waste treatment by microwave and electron beam irradiation. Proceedings of the 2nd Environmental Physics Conference, 18-22 Febrnary 2006, Alexandria, Egypt, pp. 91-100. 

Irradiation of polymers with y- or electron beams is an attractive alternative to chemical sterilization because of its speed, ease of control, and the absence of residue. Radiation treatment of polypropylene, however, also initiates chemical changes which lead ultimately to embrittlement. These changes in physical properties may not become apparent until some time after the treatment. The ability of antioxidants to prevent radiation damage does not always follow the trends observed in thermal oxidation, which has stimulated efforts to develop new stabilizers or optimized combinations of existing ones. 

Electron beam irradiation is linked to the chemical incompatibility and physical phenomenon. This affects the interfacial properties of the composites. Specific surface treatment for the reinforcing fibers and suitable sizing is a part of preparations required specifically for EB cured composites. 

Another problem limiting the application of nanociystalline materials is prep>aration of nanocrystalline alloys. Currently, the bulk metallic nanomaterials can only be prepared at the laboratory scale, usually by compacting prepared nanocrystalline powders. However, consolidation of the nanopowders into bulk materials needs high temperature and pressure which may considerably coarsen the structure. Because of this difficulty, surface nanocoating has been considered a potential industry application. Nanocrystalline costing are often prepared by chemical vapour deposition (CVD), physical vapour deposition (PVD), electrochemical deposition, electro-spark deposition, and laser and electron beam surface treatment. 

Physical methods for treating natural fibers before biocomposite processing involve electrical discharges such as cold plasma and corona, electron beam irradiation, ultraviolet (UV) treatment, and ultrasonic treatment,. Such physical approaches are of great interest because, in general, the processes are dry, clean, labor-friendly, environment-friendly, and fast in comparison with most of the chemical methods, which are wet processes. Under appropriate treatment conditions, they can effectively modify structural and surface characteristics of natural fibers, thereby improving the mechanical and thermal properties of biocomposites as well as enhancing the interfacial adhesion between the natural fibers and the polymer matrix. 

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