PROTECTIVE TREATMENTS IN FABRIC CONSERVATION

The study aims to prevent environmental induced deterioration of cellulose fabrics, linked to the presence of water and oxidizing agents. Protective formulations were developed for the conservation of cellulose fabrics, using sustainable products and application techniques. The treatments studied in this thesis conferred the desired properties to the fabrics and also fit with the Cultural Heritage conservation requirements. This means that, when applied on the object, the polymers did not cause any visible color variation and were chemically stable in time, so they maintained the original fabrics appearance and prolonged the lifetime of the object. First, the development of a hydrophobic coating based on polycarbonate diol polyurethane combined with aminosiloxane was successfully tested. Then, a multifunction coating have been developed, aiming at protecting the fabrics, not only from water linked deterioration phenomena, but also from oxidation Both studies were based onto ecofriendly materials and processes. Both dip- and spray-coating were proposed, since they are easy to apply and low cost application methods. The polymers penetrated in the core of the fabrics so to confer hydrophobicity and antioxidant properties to the bulk and not only to the surface of the fabrics. This single fibers coating was also beneficial to mainlined the high vapor permeability of the fabrics. The properties of the treated fabric were studied with several techniques: lowered wettability and water protection (contact angle, roll-off angle, moisture absorption, water vapor permeability), unchanged surface morphology (SEM, SEM-EDX), chemical characterization (ATR-FTIR, DLS, NMR), unchanged mechanical properties (stress-strain curves, Peirce Cantilever Test), efficient antioxidant properties (Radical Scavenging activity tests, ATR-FTIR analyses of oxidation peaks), and unchanged color (colorimeter). Moreover, coated fabrics were exposed to extreme peroxidative (concentrated H2O2) and UV light damage conditions using an ad hoc protocol for simulating decades of atmospheric ageing. Chemical changes on the cotton surface and potential oxidation and preventive mechanisms were studied using ATR-FTIR spectroscopy. Mechanical properties and color changes were evaluated after exposing samples to oxidation. Concluding, this study displays innovative treatments for the protection of cellulosic fabrics, respecting the original characteristics of Cultural Heritage objects, which should be maintained unaltered in time to preserve their cultural and historical value.