Inorganic nanoparticles dispersed in epoxy-based physical gels

J. PUIG; CRISTINA E. HOPPE; ILEANA A. ZUCCHI; ANA LEDO SUAREZ; MARÍA J. GALANTE; ROBERTO J.J. WILLIAMS

Los Cocos- Córdoba- Argentina

Congreso; V Congreso Binacional Argentino-Chileno de polímeros -ARCHIPOL 09; 2009

Polymer gels are fascinating materials with multiple and diverse applications as separator agents, solvent absorbers, ion exchangers, diapers, drug delivery devices, etc. (Osada et al. 2004, Sonmez and Wudl, 2005). They are wet and soft materials constituted by networks of flexible cross-linked chains with a fluid filling their interstitial space. Depending on the type of crosslink forming the network, polymer gels can be classified as chemical gels (cross-linked by covalent bonds) or physical gels (joined by weak forces as hydrogen bonds, van der Waals forces, or hydrophobic and ionic interactions). (Osada et al., 2004). Physical gelation is usually a reversible process that occurs through the so called sol–gel transition. Large swelling capacities of gels make them attractive not only as absorbents or separators but also as hosts for the development of multifunctional materials. For example, by incorporation of liquid crystals (Kato et al., 2007), or metal ions (Feldgitscher et al. 2009) to the liquid phase, materials with especial properties have been obtained. In the case of physical gels, the ability to be reversibly transformed between the liquid and the gelled states add new advantages to the obtained materials. In this work, an epoxy-based physical gel is obtained by simple bulk polymerization of a diepoxy monomer and a long-chain alkylamine followed by thermal annealing of the system above its glass transition temperature (Zucchi et al, 2009). Capacity of these gels to act as hosts for the dispersion and synthesis of metal and magnetic NPs is demonstrated. Final properties of the dried systems, as well as the ability of the networks as chelating and reducing agents of metal ions are also discussed.