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Synthesis and physicochemical characterization of silicafillers modified with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane

Szwarc-Rzepka K., Gogola N., Siwińska-Stefańska K., Marciniec B., Jesionowski T.

Polish Journal of Chemical Technology

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2013

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Vol. 15, nr 4

15-23

EN

Hybrid nanofillers of silica grafted with octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane were obtained by the method based on solvent evaporation with the use of both hydrated or emulsion spherical silica. Octakis({3-methacryloxypropyl}dimethylsiloxy) octasilsesquioxane was applied as a modifying agent and it was synthesized by employing the hydrosilylation reaction. The effectiveness of modification of the hybrid nanofillers obtained was verified using Fourier transform infrared spectroscopy and nuclear magnetic resonance (29Si and 13C CP MAS NMR). The products obtained were characterized by determination of their physicochemical properties and porous structure, including specific surface area, pore diameter and pore volume. Dispersion degree and particle size of the nanofillers was characterized by NIBS (Non-Invasive Back-scatter) method and laser diffraction technique, while their morphology by transmission electron microscopy.

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Synthesis of hepta(isobuthyl)ethyltriethoxysilyl- octasilsesquioxane and its application as a modifier of both hydrated and emulsion silicas

Szwarc-Rzepka K., Ciesielczyk F., Zawisza M., Kaczmarek M., Dutkiewicz M., Marciniec B., Maciejewski H., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 2

619-630

EN

Hepta(isobuthyl)ethyltriethoxysilyloctasilsesquioxane was synthesized by hydro-silylation of hepta(isobuthyl)vinyloctasilsesquioxane with triethoxysilane, over Karstedt catalyst and tetrahydrofuran. Hybrid systems of silica and monofunctional silsesquioxane (SiO2/POSS) were obtained by solvent evaporation, using emulsion silica (ES) and hydrated silica (HS), obtained by precipitation in emulsion or water media. For their surface modification hepta(isobuthyl)ethyltriethoxysilyloctasilsesquioxane was used. The hybrids were characterized by dispersion analysis (NIBS method and laser diffraction technique) and morphological analysis (transmission electron microscopy) as well as wettability profiles in an aqueous system. The adsorptive properties of the hybrids were evaluated on the basis of surface area BET, pore volume and size. The effectiveness of modification of the hybrid fillers was tested by FTIR and 29Si CP MAS NMR.

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Synthesis and characterisation of SiO2/POSS hybrid systems obtained using the mechanical method

Szwarc K., Siwinska-Stefanska K., Marciniec B., Jesionowski T.

Physicochemical Problems of Mineral Processing

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2012

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Vol. 48, iss. 1

181-192

EN

Hybrid systems of silica and polyhedral oligomeric silsesquioxanes (SiO2/POSS) were obtained by the mechanical method with the use of spherical or hydrated silicas, precipitated in the emulsion or aqueous environment. The SiO2 surface was modified with the following cage silsesquioxanes: hepta(isobutyl)2-triethoxysilylethyloctasilsesquioxane, octakis ({3-glycidoxy-propyl}dimethylsiloxy)octasilsesquioxane and octakis ({3-methacryloxypropyl} dimethylsiloxy)-octasilsesquioxane. The nanofillers obtained were subjected to thorough dispersive analysis (NIBS method) and morphological analysis (transmission electron microscopy). Their wettability in water systems was evaluated and their adsorption activity was characterised by determination of the specific surface area BET, pore diameters and volume. Thermal stability of the nanofillers was checked. The effect of surface modification on the degree of coverage was assessed on the basis of elemental analysis.