| Abstract
| - A range of polyviologens synthesized by the Menshutkin reaction have been successfullyincorporated into silica hybrids using the hydrolytic sol−gel route. Transparent hybrids canbe obtained with up to 75% polyviologen content, indicating a likely nanoscale morphology.Hybrids were calcined at 650 °C to remove the polymer, forming porous amorphous silicaproducts. Nitrogen adsorption−desorption studies have been undertaken on the hybrids andthe calcination products, and the results are analyzed by the modeless method of Brunaueret al. for mesopore size distributions and a micropore analysis method based on t-curves.The hybrids are mostly mesoporous solids, but porosities are very low at high polymercontents. Calcination leads to silicas which are mainly mesoporous with varying degrees ofmicroporosity depending on the nature and concentration of the polyviologen (PV) used.Poly(hexyl viologen ditosylate) produces high surface area silicas with >98% mesoporosity.The results may provide evidence for an influence of the PV on the structure of the formingsilica, which is proposed to occur through electrostatic interactions between the quaternarynitrogen atoms of the polymer and the silanol oxygen atoms in the growing silica network.
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