Biodegradable and biocompatible inorganic-organic hybrid materials. 3. A valuable route to the control of the silica porosity

Porous silica has been successfully prepared from poly(epsilon-caprolactone)-silica hybrid materials on the basis of the template approach. The final texture of the porous silica has been analyzed by the nitrogen adsorption-desorption technique and by small-angle X-ray scattering (SAXS). The porosity of silica can be tailored by the poly(epsilon-caprolactone) (PCL) template, particularly molecular weight, molecular weight distribution, content, and type and number of reactive groups per chain. Increasing the molecular weight, content, and chain polydispersity of the PCL template and decreasing the reactivity and number of reactive groups per PCL chain result in a more heterogeneous microporosity and, as a rule, in larger pores, a broader pore size distribution, a larger specific surface area, and a larger total and microporous volume.