Templated cross-linking reactions for designing nanoporous materials

Nanoporous materials are potentially useful for their permeation, dielectric, thermal and optical properties. These materials could be a future altemative for the insulating foams currently used in different industries. In order to realize such performance, highly nanoporous materials (pore size similar to 100-150 nm and porosity >= 85%) that take advantage of the Knudsen effect and low solids contribution to heat conduction are required. The potential for designing such materials by carrying out templated cross-liriking reactions using microemulsions and colloidal dispersions was investigated. It was found that these templates helped in imposing some fine pore structures (<200 nm) characteristic of them but the coarser pores (> 1 mu m) that are formed due to phase separation and aggregation effects upon cross-linking could not be avoided. As a result the thermal performance of these materials was in between the conventional macroporous foam (d(pore) similar to 40-100 gm) and sol-gel based nanoporous materials (d(pore) similar to 150 nm). (C) 2006 Elsevier B.V. All rights reserved.