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Two different diisocyanates were investigated as co-monomers for in situ polymerisation of poly(urethane-urea) into Neapolitan yellow tuff for conservation and restoration purpose. The obtained copolymers were characterised by means of FTIR spectroscopy, whereas the protective and consolidating efficiency of the performed treatments was evaluated through water capillary absorption, water vapour permeability and abrasion resistance measurements. The distribution and the penetration depth of the synthesized copolymer were also analysed applying micro-FTIR. The morphology of treated tuff was investigated by SEM. It was shown that comparatively higher protective and consolidating properties are achieved by using 1,6-diisocyanatohexane as monomer for in situ polymerisation.

In this paper the results of a research aimed at developing radically innovative process tailored for the restoration of both stone and textiles are reported. For stone, a new polymerisation procedure of poly(urethane-urea) by in situ polymerisation inside stone is described. Through the method set up a good penetration depth of the polymer into the stone pores is achieved, and the material obtained is characterized by high aggregative and consolidating efficiency. For textile materials, a new consolidating procedure, based on the grafting copolymerisation of acrylic monomers on the cellulose substrate has been set up and a high volume grafting chamber has been designed and realized, in order to carry out the grafting procedure onto large textile items of historical interest.

With the aim of better understanding the phenomena related to the application of polymeric materials on natural fiber textiles for restoration purposes, six commercial polymers based on acrylic and acetovinylic monomers are tested on modem cotton textiles. Cotton samples are impregnated with water dispersions of these polymers. The morphology of the polymeric films formed on the surfaces of the fibers, the chromatic and consolidating effects of the applications, and the adhesive properties of the polymers are investigated. The morphology of the films coating the fibers is independent of the morphology of the fibers constituting the textile substrate. There are no relevant chromatic effects related to the application of polymeric materials on cotton fabrics, indicating that treatments should be compatible with the aesthetic of cotton items. The consolidating effect of application is evaluated on cotton yarns artificially degraded in HCl solution, and depends strictly on the amount of polymer applied. Peel strength values exhibited by cotton samples prepared by compression molding and under vacuum suggest that the most useful adhesive agents are those with a Tg slightly lower than room temperature.