7. Conclusion

A polymer is a macromolecule with a well-defined size and molecular weight. Several complementary physical methods are needed to measure its characteristics in the solid state (electron microscopy) or in solution (light scattering). We have seen how (K)-poly(sialate) and (K)-poly(sialate-siloxo) geopolymers are made up of individual elementary nanoparticles of 5 to 20 nm in size (50 to 150 Å) separated by a nanoporosity of the order of 3 to 10 nm. This microstructure forms at room temperature and remains stable at temperatures above 1,000°C. Kriven et al.