Multiscale Viscoelastic Investigation of Silica-Calcium-Phosphate Sol-Gel Materials

Abstract

The sol-gel transition of homogeneous biocomposites synthesized using tetraethyl-orthosilicate alkoxide, calcium nitrate tetra hydrate and di-ammonium hydrogen phosphate salts as reagents are investigated at the macroscopic scale by small amplitude oscillatory shear measurements and probed locally by passive microrheology at 37 °C. Structural evolutions during the sol-gel transition are studied by using Fourier Transform Infrared (FT-IR) analysis. The Young’s modulus of the aged gels is measured as a function of time, at room temperature. Moreover the materials are dried, thermally treated and characterized by laser scattering analysis and X-ray diffraction to obtain the particle size distribution and crystallite size respectively and to observe the morphology by Scanning Electron Microscopy.

Keywords

• gels
• sol-gel transition
• microrheology
• compression
• ftir
• sem