Water-dispersed polymers for the conservation and restoration of Cultural Heritage: A molecular, thermal, structural and mechanical characterization

A molecular, thermal, structural and mechanical characterization of two different commercial water-dispersed polymers, i.e. an unreactive aliphatic polyetherurethane (trade name Akeogard AT40) and a VDF/HFP/TFE terpolymer (trade name Fluorobase T300) has been performed by means of differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMTA), Fourier transform infrared spectroscopy (FTIR) and Fourier transform nuclear magnetic resonance (FT NMR), wide and small angle X-ray scattering (WAXS and SAXS) techniques and an Instron machine. Such polymers were selected from among the available products used for conservation and restoration by Cultural Heritage, with the view of using water-based polyurethanes and fluorinated copolymers as coatings for artefacts belonging to Cultural Heritage, consisting of natural fibrous polymers, mainly textiles. The results obtained so far suggest that a comparatively higher potential for the conservation and restoration of textiles with a cultural value is shown by AT40 polyurethane. Notwithstanding this, the structural properties assessed in water-cast films for both the polymers indicate that desired properties could be conferred by suitably selecting the chemical and molecular structure of the starting monomeric units.