Hybrid PDMS-Silica-Zirconia materials prepared by γ-irradiation

Hybrids are a class of materials that enable the integration of organic and inorganic characteristics at the molecular level in a single material. In this way materials with unusual optical, mechanical or even bioactive properties are obtained, which are especially suitable for applications as sensors, non-linear optical (NLO) materials, lasers, selective membranes, catalysts and protective coatings. Sol-gel processing is often used for the preparation of hybrids, usually through the alkoxides method that leads to high purity products at relatively low temperatures. The authors have developed a new method for the preparation of these materials based on gamma irradiation of the precursors mixture. The precursors used are polydimethylsiloxane (PDMS), tetraethylortosilicate (TEOS) and zirconium propoxide (PrZr). The irradiations were performed using the 60Co source at the Portuguese Gamma Irradiation Facility (UTR) located in the ITN campus at Sacavém. The materials at room temperature are macroscopically transparent, relatively flexible and amorphous. The details of the preparation of these hybrid materials by gamma irradiation are presented.