Sol-Gel-Derived Silicon-Containing Hybrids

Abstract

Silicone-containing hybrid systems including functionalized and modified silica nanospheres as well as silica aerogels were synthesized using sol-gel process. The most important advantage of the developed silicon-containing hybrids lies in their high application potential, e.g. for the production of façade paints, polymer nanocomposites, highly efficient insulating materials and other high-tech products for construction industry. The possibility of precise steering of sol-gel process and synergism of very rich silicon compound chemistry allows to obtain materials with strategically designed architecture. Original methods of manufacturing following silicon-containing hybrids such as functionalized and non-functionalized silica nanospheres, silica nanospheres containing immobilized silver and/or copper nanoparticles and silica aerogels were developed. Homogeneous structural properties of synthesized materials were achieved due to carefully selected parameters of sol-gel process. The technology offers a possibility to control the grain size and uniformity of nanospheres by process parameters. The smallest nanosphere size is 10 nm and the largest 600 nm. The properties of aerogels obtained according to the original technology developed in the Industrial Chemistry Research Institute (ICRI) are extremely good and repetitive particularly taking into account their thermal conductivity. The main advantages of the developed aerogels are very good mechanical properties, very low dust formation and significantly decreased costs when compared to traditional silica aerogels.

The use of modified silica to control the morphology of polyamide 11 and poly(phenylene oxide) blends

“…Amorphous poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) was supplied by Sabic GE Plastics Co. USA under the trade name Noryl V0150B, with the melt flow rate of 4 g/10 min (at 300°C and 5 kg). Modified silica having 0.35 wt % of amine functional groups (A-SiO 2 ), with an average diameter of 30 nm and specific surface area of 274.4 m 2 /g, was prepared by the reported sol-gel method [19,20] and used as a compatibilizer at a concentration of 1, 3 and 5 wt. %.…”

“…Silica having amine functional groups (A-SiO 2 ) was synthesized using a procedure published elsewhere [19,20]. Briefly, tetraethoxysilane (TES 28, Wacker Chemie, Germany) was added as a precursor to ethyl alcohol, aqueous ammonia and distilled water mixture, and stirred for 2 hours.…”

Characteristics of Biodegradable Polylactide/Thermoplastic Starch/Nanosilica Composites: Effects of Plasticizer and Nanosilica Functionality

“…Neat (SiO 2 ) and modified (having amine functional groups) spherical silica (A-SiO 2 ) nanoparticles synthesized according to the previously reported sol-gel process [40][41][42] were used as nanofillers. Tetraethoxysilane (TEOS), technical grade, commercial product name TES 28, was supplied by Wacker Chemie (Germany).…”

“…Neat (SiO 2 ) and modified (heavy amine functional groups) spherical silica (A-SiO 2 ) were synthesized according to the developed sol-gel process using tetraethoxysilane (TEOS) as alkoxysilane precursor at room temperature (23°C), with a stirring speed of 250 rpm [40][41][42]. e process was carried out in an aqueous ammonia-ethyl alcohol reaction mixture using molar ratio of TEOS/EtOH/H 2 O as 0.023/0.500/0.477, and the initial pH ranged from 10.4 to 11.3. e final pH range was 7.5-10.8. e pH of the reaction mixture was measured using a pH meter (Schott Instruments LAB 850).…”

Morphology and Properties of Poly(2,6-dimethyl-1,4-phenylene oxide)/Polyamide 11 Hybrid Nanocomposites: Effect of Silica Surface Modification

“…Biobased semicrystalline polyamide 11 (PA11), Rilsan, with MFR 22 g/10 min (measured at 235 °C and 10 kg), was supplied by Arkema France. Neat (SiO 2 ) and modified silica having 0.35 wt.% of amine functional groups (A-SiO 2 ), with an average diameter of 30 nm and specific surface area of 274.4 m 2 /g, were prepared by the reported sol–gel method [ 30 , 31 , 32 ] and used at concentrations of 1 and 5 wt.%.…”