PRODOTTI NANOSTRUTTURATI PER LA PROTEZIONE DI SUPERFICI LAPIDEE: VALUTAZIONE DELL’EFFICACIA MEDIANTE TECNICHE FISICHE NON INVASIVE

The use of nanoproducts in the Cultural Heritage (CH) field requires great sensitivity and responsibility and, above all, analytical research and studies evaluating effectively their potential use. In order to evaluate the capability of nanostructured protective in the CH field, limestone materials of historical-artistic interest were treated and then studied. The study focuses on the non-invasive evaluation of samples stone, of interest in the CH field, their surface has been tested with nanostructured products. In particular, samples of limestone of Favara (Sicily) have been studied, before and after artificial aging. The analytical methodology involved X-ray fluorescence measurements, in order to evaluate the elemental composition differences between treated and untreated samples; spectrophotometric measurements to determine the colour changes due to the protective application, contact angle estimations on the untreated/treated surfaces and, finally, evaluation of the amount of the absorbed water by capillarity. The samples were, also, artificially aged inside a microclimate chamber, in order to evaluate how the waterproofer properties of the nanostructured products are affected by temperature and humidity. The investigation, repeated after saline chamber, allowed to evaluate the treatments effectiveness and, in particular, their persistence after aging through Si presence/absence, selected as a XRF marker of nanostructured protective layer.