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With the use of stereolithography, one of the most widespread and old rapid prototyping techniques, it is possible to reproduce objects, damaged or missing parts, faithful replicas of interest in the field of Cultural Heritage. In this work, some of the applications of the stereolithography technique to replicate objects or missing parts of artistic or cultural interest, are illustrated. The aim of the Authors is to highlight the potential, the advantages, and also the limits if any, of this technique when applied in the field of Cultural Heritage for various needs, reporting some real cases of objects obtained in the laboratory with stereolithography.

The most studied polymer nanocomposites are composed of thermoplastic matrix and organically modified montmorillonite. Photo-differential scanning calorimetryand fourier transform infrared spectroscopy were used to study the effect of the inclusion of nanofiller on the kinetics of polymerization. Trimethylolpropane trimethacrylate was chosen as the main polymeric component of the coating, due to its high reactivity. In order to verify if the presence of boehmite nanoparticles affects the transparency of the polymeric matrix, light transmittance measurements were performed on the photo-cured films coated on a glass support. The characterization of the physical and surface properties of photopolymerizable siloxane-modified methacrylic-based/boehmite nanocomposite was also performed in order to quantify the modifications in properties brought about by the presence of nanoparticles finely dispersed in the thermosetting matrix. The presence of a residual reactivity before the QUV treatment was explained by the completion of homopolymerization reactions of the unreacted silane monomers.

The effects of environmental aging at various levels of humidity were studied on the experimental formulations of epoxy-silica hybrids, specifically designed for curing at ambient temperature to be employed as adhesives for concrete and/or masonry structures. The addition of small amounts of ammonium molybdate to the amine hardener was investigated using thick section specimens (4.5 mm thick) capable of retaining substantial amounts of ethanol either originally added to the resin mixture or subsequently formed by the sol-gel hydrolysis and condensation reactions. The changes taking place during aging were evaluated in terms of variations in glass transition temperature (Tg), water absorption and mechanical properties. It has been found that during environmental aging in moist atmosphere the siloxane domains of the epoxy-silica hybrids undergo additional sol-gel reactions, which bring about a further increase in Tg and substantial increases in Young's modulus (Eflex) and flexural strength (?max flex). The observed effects were found to be enhanced by the addition of small amounts of ammonium molybdate to the formulation. Furthermore, the moisture in the atmosphere was found to assist the extraction of the residual ethanol in the specimens.

The absorption/desorption behavior of a commercial cold-cured bisphenolic epoxy resin, subjected to different treatments prior to exposure to water, was analyzed. The epoxy system has been already used as both matrix and adhesive for the manufacture and application, respectively, of fiber reinforced polymers composites employed for rehabilitation procedures. The effects of different curing, conditioning, and storing conditions on the water absorption/desorption process taking place in the cured resin were evaluated. The different conditioning procedures used to dry the specimens before their exposure to water caused a different extent of physical aging and of curing on each system, influencing the amount and the rate of diffusion of the water molecules inside the specimens. Moreover, if the specimens are subjected to thermohygrometric cycles prior to immersion in water, the rate of diffusion and the amount of water also depends on the presence of water molecules inside the cured resins not easy to remove by any drying treatment. During all the hygrometric treatments performed, a deaging process took place. The kinetic of this deaging process for the not-fully cured systems depends on the additional crosslinking taking place in the samples. The different procedures used to condition the specimens also affect the variations in glass transition temperature (Tg) of the cured systems during and after immersion in water. Finally, the different drying procedures employed proved to be not equally appropriate for cold-cured epoxy resins.

Epoxy resins find wide applications in many fields and have been extensively studied. In particular, great effort has been devoted to the study of the mechanism of crosslinking reactions analysing the factors affecting the molecular network and the physical properties of the hardened material. A detailed understanding of the "curing process" and of the structure-properties relationship, in fact, is essential to control and optimise the process parameters in order to tailor the performance of the of cured systems. Different analytical techniques have been employed to this aim. Among them, FTIR (Fourier transform infrared) spectroscopy has proved to be very helpful allowing quantitative measurements of the variations of functional groups during the crosslinking reactions. In the present work, a review of the scientific publications dealing with the application of FTIR to study the mechanism and the kinetic of the "curing process" of epoxy resins hardened with amines, is presented. This kind of formulation, in fact, is one of the most frequently used and, therefore, has been extensively studied. The main characteristic absorbance peaks of epoxy-amine systems have been listed and discussed. Finally, the kinetic equations more widely employed to determine the degree of conversion and the kinetic parameters, have been reported.