surface modification

A new approach to synthesis at the aminated glass surface of novel biocompatible polymeric nanolayers consisting of poly(N-methacryloyl-L-proline) brushes has been developed. Formation of the polymer nanolayers has been realized in several stages. At the first stage, the glass surface has been modified by aminosilane (APTEC), afterwards monolayer of the peroxide-containing initiator (PI) based on pyromellitic acid has been tethered to this aminated surface.

Water-dispersed fluorescence nanomaterials based on boron nitride nanotubes and grafted copolymer brushes (poly(acrylic acid-co-fluorescein acrylate) were successfully fabricated in a two-step process. The functionalization of BNNTs was confirmed by spectroscopic, gravimetric and imaging techniques. In contrast to “pure” BNNTs, functionalized BNNTs demonstrate intense green fluorescence emission at 520 nm. The developed hybrid structure can potentially be used for cellular imaging, as “smart” surfaces, nanotransducers and nanocarriers.

Polymerizable organic silane molecules 3-(trimethoxysilyl)propylmethacrylate (3MPS) and vinyltri(2-methoxyethoxy)silane (VTMES) have been introduced onto surfaces of high purity Boehmite (a commercial alumina) via hydroxyl groups on the oxides in order to obtain organic-inorganic hybrid “macromonomers”. Changes of surface characteristics have been determined using thermogravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FTIR). The influence of the type of silane used and modification conditions have been determined.

Via radical reactions of chitosan and 5-tert-butylperoxy-5-methyl-1-hexen-3-in peroxychitosanes with ditertiary peroxide fragments were synthesized. They can be used as macroinitiator and coemulsifiers for emulsion polymerization of vinyl monomers. Latex polymers obtained antibacterial properties. Polymeranalogical interaction of chitosan with tert-butylperоxymethyl ester of butendicarbon acid yields in peroxychitosanes with controlled quantity of primary-tertiary peroxide fragments. New pH-sensitive smart hydrogels with antibacterial properties were created on their basis.

In this paper the results of recent studies on the application of lower critical solution temperature (LCST) phenomena of polymer solutions to the surface modification of flat and spherical substrates are reported. It has been found that controlled polymer deposition can be achieved at temperatures exceeding LCST. The obtained polymer coating exhibits a peculiar surface morphology and, if particles are introduced, can be highly effective in pigment dispersions stabilizing.

The synthesis of titanium(IV) oxide nanopowders modified by sulfur with the help of sol-gel method has been described. The structure of surface layers has been investigated using X-ray diffraction analysis, a scanning electron microscopy, IR-spectroscopy and X-ray photoelectron spectroscopy. The possible mechanism of powders surface modification by sulfur has been shown, as well as the dependence of specific surface on sulfur content.

Flame-retardant polymer composites based on homo- or copolymers of propylene as the matrix polymer and dispersed magnesium hydroxide, surface-modified by polyperoxides, as the filler have been obtained and characterized. The influence of the polyperoxide nature and the content of peroxide groups immobilized at the filler surface onto the mechanical and rheological properties as well as flame retardancy of composites have been studied.