Electron beam modification

Keywords Chemical coupling Elastomer Electron-beam modification Friction and wear properties Mechanical properties... 

Electron beam modification of PTFE nanopowder resulted in increasing concentration of radicals and carboxyhc groups (—COO H) with increase in irradiation dose. Low-temperature reactive mixing of the modified PTFE with ethylene-propylene-diene-monomer (EPDM) rubber produced PTFE coupled EPDM rubber compounds with the desired physical properties due to the formation of a compatible interphase this was confirmed by transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) [56]. 

Vijayabaskar, V, Tikku, V. K., Bhowmick, A. K. (2006). Electron beam modification and crosslinking Influence of nitrile and carboxyl contents and level of unsaturation on structure and properties of nitrile rubber. Radiat. Phys. Chem., 75(7), 779-792. 

Grigoriev S.V., Koval N.N., Ivanov Yu.F., et al. Electron beam modification of the surface of steel and hard alloys. Plasma emission electronics. - Proceedings of II International Kkreyndelevsky seminar. - Ulan-Ude, 2006. P. 113-120. 

Miscellaneous. Electron beams can be used to decompose a gas such as silver chloride and simultaneously deposit silver metal. An older technique is the thermal decomposition of volatile and extremely toxic gases such as nickel carbonyl [13463-39-3] Ni(CO)4, to form dense deposits or dendritic coatings by modification of coating parameters. 

Electron beam-initiated modification of polymers is a relatively new technique with certain advantages over conventional processes. Absence of catalyst residue, complete control of the temperature, a solvent-free system, and a source of an enormous amount of radicals and ions are some of the reasons why this technique has gained commercial importance in recent years. The modification of polyethylene (PE) for heat-shrinkable products using this technique has been recently reported [30,31]. Such modification is expected to alter the surface properties of PE and lead to improved adhesion and dyeability. 

Parameters/Units Used in Electron Beam Radiation-Induced Modification OF Materials... 

Attempts to perform the MAED of these crystallites were unsuccessful because of the difficulty In observing the crystallites with the small objective apertures necessary to obtain reasonable MAED patterns, and the rapid mobility of these small crystallites In the stationary electron beam used In the MAED mode. Instrumental modifications are commercially available which might allow this measurement to be made. 

Quantitative Analysis. In its basic form, AES provides compositional information on a relatively large area ( 1 mm2 ) of surface, using a broad-focussed electron beam probe. Sufficient signal may be obtained in this way with a low incident electron flux, thus avoiding potential electron-induced modifications of the surface. 

Micro- (and even nano-) electrode arrays are commonly produced with photolithography and electronic beam techniques by insulating of macro-electrode surface with subsequent drilling micro-holes in an insulating layer [136, 137], Physical methods are, however, expensive and, besides that, unsuitable for sensor development in certain cases (for instance, for modification of the lateral surface of needle electrodes). That s why an increasing interest is being applied to chemical approaches of material nanostructuring on solid supports [140, 141],... 

Coatings and Surface Modifications. Probably the one application of photopolymer chemistry that has the most worldwide commercial value in terms of product sales is the use of photopolymer materials for curable coatings. Most of the wood paneling and less expensive furniture manufactured today utilize UV or electron-beam curable materials for decorative finishes (e.g. simulation of wood grain) and protective coatings. In addition, the surfaces of many commercially important materials (e.g. textile fibers and polyester films) are being modified by photopolymer processes. 

Although the mechanism by which modification of surfaces in UHV occurs is not clear for all cases, local heating effects appear to have effected the observed modification of glassy materials such as Pd81Si19 (81) and Rl Zr- j (82). The fluence of electrons from an STM tip has been used to accomplish nanometer scale electron beam lithography of CaF2 coated substrates (83). A somewhat different... 

The main modification that enables the system to analyze in situ reactions is the custom built chamber for the STM stage with indirect heating via an electron beam. Therefore, the sample can be brought to the desired temperature and pressure without disturbing surface interactions. While this technique is primarily used for model catalysts to be studied, it provides very good insight into the mechanisms present over a range of pressures. 

Applying ion beams, surface-sensitive analysis and modification in atomic and electronic structures of inorganic materials have been developed. Ion beam modification of titanium dioxide (Ti02), carbon-based materials, and the analysis of Nb/Cu multilayers and VO2 using ion beam are described as follows. 

A comprehensive review of radiation techniques in the formulation of biomaterials was published by Kaetsu. Substrate modification by electron beam was discussed by Wendrinski at the meeting of RadTech Europe 2001. ... 

Natural Rubber and Synthetic Polyisoprene Polybutadiene and Its Copolymers Polyisobutylene and Its Copolymers Ethylene-Propylene Copolymers and Terpolymers Polychloroprene Silicone Elastomers Fluorocarbon Elastomers Fluorosilicone Elastomers Electron Beam Processing of Liquid Systems Grafting and Other Polymer Modifications... 

For the last 50 years, radiation processing by gamma rays, electron beams (E-beams) or X-rays has been an effective technique for improving the end-use properties of various kinds of polymers. The main applications for modification of... 

The last contribution in the prevailing volume deals with the application of a relatively new class of materials based on the addition of (electron-beam) activated polytetrafhioroethylene (PTFE) powder in rubber matrixes for preparing PTFE-based elastomeric composites. Besides other properties, the remarkably lower friction coefficient of PTFE enables its utilization for tribological applications. However, PTFE in rubbers has not been fully explored mainly due to its inherent chemical inertness and incompatibility. The present work signifies the electron modification of PTFE powder to improve its compatibility with rubber matrixes, the state of the art regarding its application in rubbers, and the preparation of PTFE-based elastomeric composites for several tribological applications. 

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