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The modification of the surface of low density polyethylene (LDPE) and polyurethane (PU) by means of the pulsed ion-plasma deposition of nanostructural carbon coatings at 20-60°C has been studied. The effect of this low temperature treatment on the biocompatibility of the LDPE and PU has been assessed. Optimum technological parameters for the formation of mosaic carbon nanostructures with a thickness of 0.3-15 nm and a cluster lateral size of 10-500 nm are determined. These structures give the polymer surface increased hemocompatible properties. The surface of samples was studied by methods of scanning electron microscopy, scanning probe microscopy, and Raman spectroscopy. The effect of the UV light of a krypton lamp (λ = 123.6 nm) and white synchrotron radiation on the surface of poly(methyl methacrylate) (PMMA) preliminarily treated in an oxygen containing RF discharge plasma has been investigated by varying the dura tion of exposure (from several minutes to several dozen minutes) and the residual gas pressure (2 and 100 Pa). This processing ensures the smoothing of the surface relief on micro and nanoscale levels, which can improve the biocompatibility of the modified PMMA film surface. The principles of a two stage technology for rendering the titanium (implant) surface biocompatible are developed. This technology consists of the chemical pretreatment of the surface for creating a microrelief (2-3 μm roughness), followed by the deposi tion of a titanium oxide film with controlled composition (TiO 2) and thickness (10-60 nm). The influence of the mechanisms and technological parameters of the oxide film deposition on its composition, structure, uni formity (conformal coating of involved shapes), and biocompatibility of the modified surface have been stud ied.

Polysaccharide processing by means of low-temperature Electron Beam Plasma (EBP) is a promising alternative to the time-consuming and environmentally hazardous chemical hydrolysis in oligosaccharide production. The present paper considers mechanisms of the EBP-stimulated destruction of crab shell chitin, cellulose sulfate, and microcrystalline cellulose, as well as characterization of the produced oligosaccharides. The polysaccharide powders were treated in oxygen EBP for 1–20 min at 40 °C in a mixing reactor placed in the zone of the EBP generation. The chemical structure and molecular mass of the oligosaccharides were analyzed by size exclusion and the reversed phase chromatography, FTIR-spectroscopy, XRD-, and NMR-techniques. The EBP action on original polysaccharides reduces their crystallinity index and polymerization degree. Water-soluble products with lower molecular weight chitooligosaccharides (weight-average molecular mass, Mw = 1000–2000 Da and polydispersity index 2.2) and cellulose oligosaccharides with polymerization degrees 3–10 were obtained. The 1H-NMR analysis revealed 25–40% deacetylation of the EBP-treated chitin and FTIR-spectroscopy detected an increase of carbonyl- and carboxyl-groups in the oligosaccharides produced. Possible reactions of β-1,4-glycosidic bonds’ destruction due to active oxygen species and high-energy electrons are given.

Investigations of saturation behaviors of growth rate and valence band states in TaOx (tantalumethoxide and plasma-activated hydrogen) ALD process.