SYNTHESIS AND CHARACTERIZATION OF NEW ORGANIC INORGANIC HYBRID NANOSILICA FILLERS PREPARED BY SOL-GEL REACTION

L. MUSANTE; P. VÁZQUEZ; R. TORREGROSSA; J. M. MARTIN MARTINEZ

Composite Interfaces

elsevier

Año: 2010

0927-6440

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman";} p.CM7, li.CM7, div.CM7 {mso-style-name:CM7; mso-style-next:Normal; margin-top:0cm; margin-right:0cm; margin-bottom:27.5pt; margin-left:0cm; mso-pagination:none; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:Arial; mso-fareast-font-family:"Times New Roman"; mso-bidi-font-family:"Times New Roman";} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 3.0cm 70.85pt 3.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> In light of the success of making multicomponent sol gel glasses, in this study the synthesis of new hybrid nanosilicas with controlled hydrophilic/hydrophobic properties was carried out by incorporating organic based species with appropriate functional groups to inorganic based alkoxides by co-condensation reaction. Furthermore, in this study the acidity and the water content during reaction synthesis was proven to be critical in controlling the structure of the hybrid nanosilicas. These nanosilicas with different hydrophobicity were obtained by using TEOS (tetraethylortosilicate) and 10 wt% two organic modifiers (tris-hydroximethylaminometane TRIS and 1,1,1,3,3,3–hexamethyldisilazane HDMS). The average diameter of the nano-particles ranged between 7 and 10 nm. The addition of the organic modifiers changed the pH of the hybrid nanosilicas, in a different extent depending on the nature of the organic modifier. The hydrophobicity in the hybrid nanosilicas was estimated from pH measurements in water and ethanol, and from IR spectroscopy. Therefore, the extent of hydrophobicity in hybrid nanosilica fillers can be tailored by incorporating during synthesis different organic modifiers on the network. Finally, the measurement of pH of the hybrid nanosilicas in solvents with different polarity/acidity is a simple and efficient method to assess the hydrophobicity of the nanosilicas.