Consecutive hydrosilylation-based syntheses were performed of silsesquioxanes containing mixed groups 1H,1H,2H,2H-perfluorooctyl (PFD) or octafluoropentyloxypropyl (OFP) and trimethoxysilylethyl (TMS) in different stoichiometric ratios. The presence of TMS makes it possible to form covalent bonds with substrates due to the reactivity of this group. All obtained derivatives were applied to hydrophobization of glass plates and by comparison of water contact angles (WCA) on modified surfaces the effect of silsesquioxane structure as well as TMS and fluoroalkyl group contents on hydrophobic properties was determined. Moreover, an additional glass plates surface modification was performed in order to obtain superhydrophobic surfaces. Two silica types of different specific surface (300 and 130 m 2 /g) and particle size (7 and 16 nm) parameters were used in this case for initial surface modification in order to increase its roughness. Irrespectively of particle size of applied silica, a dependence was found between the increase in water contact angle and the number of fluoroalkyl substituents in a molecule.

Very efficient syntheses of new fluorocarbofunctional silsesquioxanes (spherosilicates) were performed via direct hydrosilylation with octakis(hydrospherosilicate) catalyzed by [Rh(μ-OSiMe 3 )(cod) 2 ] 2 . This method appeared to be very effective for successive (tandem) hydrosilylation of two different olefins, which permits almost quantitative syntheses of spherosilicates with mixed fluoropentyloxypropyl and glicydoxypropyl functional groups of desired stoichiometric ratios. All newly synthesized compounds were isolated and characterized by spectroscopic methods.

Recently, silsesquioxanes have been recognized as a new group of film-forming materials. This study has been aimed at determining the effect of the kind of functional groups present in two different open-cage structure POSS molecules on the possibility of the formation of Langmuir monolayers and their properties. To achieve this goal, two new POSS derivatives (of open-cage structures) containing polyether and fluoroalkyl functional groups have been synthesized on the basis of a hydrosilylation process. An optimization of the process was performed, which makes it possible to obtain the above-mentioned derivatives with high yields. In the next step, the Langmuir technique was applied to measurements of the surface pressure (π) - the mean molecular area (A) isotherms during the compression of monolayers formed by molecules of the two POSS derivatives considered. Subsequently, the monolayers were transferred onto quartz plates according to the Langmuir-Blodgett technique. Both derivatives are able to form insoluble Langmuir films at the air-water interface, which can be transferred onto a solid substrate and effectively change its wetting properties.

Hydrophobic powders were obtained via surface modification of silica or magnesium silicate with selected silanes. A modified precipitation method, carried out in an emulsion system, was used for monodisperse silica synthesis, while magnesium silicate was precipitated in a traditional water system. Functionalization of the obtained inorganic supports was performed with selected alkylsilanes: one newly synthesized, 3-(2,2,3,3,4,4,5,5-octafluoropentyloxy)propyltriethoxysilane (OPF), and two commercial, octadecylsilane (ODS) and octyltriethoxysilane C 14 H 32 O 3 Si (OCS), in amounts of 3, 5, or 10 weight parts by mass of SiO 2 . It was determined how the chemical modification of the silica or magnesium silicate surface affected its physicochemical properties. The dispersive characteristics of both unmodified and functionalized silica-based systems were evaluated. The morphology and microstructure of the samples obtained were analyzed using scanning electron microscopy. The parameters of porous structure of the prepared systems were evaluated on the basis of BET equation as well as nitrogen adsorption/desorption isotherms. Wettability tests as well as elemental analysis of the obtained inorganic oxide hybrids were also performed. In order to verify the effectiveness of silica and magnesium silicate surface functionalization with selected silanes, FTIR spectra were investigated. The resulting experimental data allowed calculation of the degree of coverage of the silica-based systems with modifying agents.

Fluorofunctional silanes, polysiloxanes and silsesquioxanes were used for the modification of glass surfaces and their influence on hydrophobic properties were determined. To increase hydrophobicity of the surface, the modification was performed in two stages: (i) by a pretreatment using a silica sol (a rise in the surface roughness), and (ii) modification with the above silicon compounds. The hydrophobicity was determined by measuring the contact angle by drop profile tensiometry. The fluorocarbofunctional organosilicon derivatives examined were found to be good precursors for the synthesis of highly hydrophobic materials and coatings. In some cases the contact angles measured after surface modification exceeded 150 , i.e. they fell in the range characteristic of superhydrophobic surfaces.

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Efektywna synteza fluorofunkcyjnych (poli)siloksanówStreszczenie -Przeprowadzono badania nad syntez¹ fluorofunkcyjnych polisiloksanów opart¹ na procesach hydrosililowania fluorowanych eterów allilowych, których prekursorami by³y alkohole fluorowane. Porównano aktywnooeae katalityczn¹ kompleksów platyny i rodu w badanej reakcji i wyselekcjonowano najbardziej aktywny, bazuj¹cy na siloksylowym kompleksie rodu. Przeprowadzono tak¿e immobilizacjê wybranego kompleksu za pomoc¹ czterech ró¿nych cieczy jonowych i porównano aktywnooeae katalityczn¹ wytworzonych uk³adów, w wielokrotnie powtórzonym cyklu reakcyjnym, przy u¿yciu takiej samej porcji katalizatora. S³owa kluczowe: polisiloksany, fluoropolimery, hydrosililowanie, ciecze jonowe, immobilizacja. EFFECTIVE SYNTHESIS OF FLUOROFUNCTIONAL (POLY)SILOXANESSummary -Synthesis of fluorofunctional polysiloxanes based on hydrosilylation of fluoroalkyl ethers (precursors of the latter were fluoro alcohols) was studied. The most active catalyst, based on rhodium siloxide complex, was selected on the ground of a comparison of the catalytic performance of platinum and rhodium complexes. The rhodium complex was immobilized in four different ionic liquids and catalytic activities of the obtained systems were compared, while performing multiple reaction runs with the use of the same portion of catalyst.