Polystyrene-block-poly(ethylene oxide) copolymers as templates for stacked, spherical large-mesopore silica coatings: dependence of silica pore size on the PS/PEO ratio.
Large-mesopore silica films with a narrow pore size distribution and high porosity have been obtained by a sol-gel reaction of a silicon oxide precursor (TEOS) and using polystyrene-block-poly(ethylene oxide) (PS-b-PEO) copolymers as templates in an acidic environment. PS-b-PEO copolymers with different molecular weight and composition have been studied in order to assess the effects of the block length on the pore size of the templated silica films. The changes in the morphology of the porous systems have been investigated by transmission electron microscopy and a systematic analysis has been carried out, evidencing the dependence between the hydrophilic/hydrophobic ratio of the two polymer blocks and the size of the final silica pores. The obtained results prove that by tuning the PS/PEO ratio, the pore size of the templated silica films can be easily and finely predicted.
University of Torino, Department of Chemistry, Via P. Giuria 7, 10125 Torino, Italy.
Roberto
R
Nisticò
University of Torino, Department of Chemistry, Via P. Giuria 7, 10125 Torino, Italy,; NIS and INSTM Reference Centre, Via P. Giuria 7, 10125 Torino, Italy.
Giuliana
G
Magnacca
University of Torino, Department of Chemistry, Via P. Giuria 7, 10125 Torino, Italy.
Sushilkumar A
SA
Jadhav
University of Torino, Department of Chemistry, Via P. Giuria 7, 10125 Torino, Italy,; NIS and INSTM Reference Centre, Via P. Giuria 7, 10125 Torino, Italy.
Dominique
D
Scalarone
block copolymers; controlled porosity; mesoporous silica; soft templating; sol–gel