A novel series of bio-based polyurethane composite foams was prepared, employing a cellulose-derived polyol for chain extension and cellulose-citrate as a thickener additive. The utilized polyol was obtained from the reduction reaction of cellulose-derived bio-oil through the use of sodium borohydride and iodine. Primarily, we produced both rigid and flexible polyurethane foams through chain extension of the prepolymers. Secondly, we investigated the role of cellulose citrate as a polyurethane additive to improve the mechanical properties of the realized composite materials. The products were characterized by FT-IR spectroscopy and their morphologies were analysed by SEM. Mechanical tests were evaluated to open new perspectives towards different applications.

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The diffusion of plastic materials had and still has a significant impact on the environment. Among these, PVC (polyvinylchloride) is certainly able to guarantee the best cost/performance ratio, high sustainability and absolute recyclability. In particular, this work refers to cement-based mortars with PVC compound used for electric cables sheathing. The aim was to verify the potential of a "new" mix-design in terms of energy efficiency and mechanical resistance of the finished products. Some mortar specimens were prepared using as basic components cement, water, sand and PVC as powder and granules. The plastic aggregate, in volumetric substitution of the sand, has been varied in proportions varying up to 50 % of the dry component. Different mixtures were prepared, all referred to a base one without PVC, to evaluate its influence on workability, thermal conductivity, compressive and flexural strength, capillary water absorption. Experimental results have shown that increasing the amount of PVC reduces density as well as compressive and flexural strength. However, PVC mortars show a greater resistance to capillary water absorption compared to the reference one, while the thermal conductivity values slightly decrease. This study is the basis for subsequent research based on further combinations of aggregates.

The economic viability of shallow geothermal systems with Borehole Heat Exchangers (BHEs) strongly depends on the thermal load which can be efficiently and sustainably exchanged with the ground. This quantity is usually defined as geothermal potential and, as reported in literature, it mostly depends on the thermal conductivity and the undisturbed temperatures of the ground. The GRETA Project funded by the EU Interreg Program Alpine Space aims to produce maps of the geothermal potential in pilot areas across the Alpine territory to identify the most suitable areas for shallow geothermal installations. This paper presents the case study of the Aosta Valley, where the recently developed G.POT (Geothermal POTential) method was adopted. It describes the data sources used and the assumptions made to derive input parameters (ground thermal properties, usage profile, etc.). In addition, the results of a survey on existing geothermal installations are presented.

Building insulation is commonly realized using materials obtained from petrochemicals or from natural sources processed with high energy consumptions, causing significant harmful effects on the environment. The "sustainability" applied to building design has encouraged many researches to develop thermal and acoustic insulating materials using natural or recycled materials. Many natural materials were already used in ancient times to thermally insulate the dwellings and to give resistance: straw and reed are some representative examples. Aim of this paper is to evaluate the influence of reed stems and straw on the thermal and mechanical performances of cement. To reach this, several types of mixes were prepared: a specimen as reference mix without any addition of fibers and some more specimens with reed only, with straw only, and finally the combination between straw and reed in different percentage. The tests were performed to determine the thermal conductivity, the compressive and flexural strength of the cement mortar panels. The results showed that straw, if combined with reed stems, could be considered as a valid reinforcement in a cementitious matrix characterized by enhanced thermal insulation and good mechanical properties. ENEA researchers have also applied a statistical method to the obtained test results in order to develop a predictive model of compression and flexural behavior of fiber-reinforced specimens with different percentages of organic fibers in the mixture cementitious.