The EnergyEfficient and EnvironmentallyFriendly VetiverPolyurethane Thermal Insulation Foams This experimental research investigates the thermal conductivity and mechanical properties of the rigid thermal insulation foams fabricated from mixtures of vetiver fibers (VF) and the polyurethane (PU) composites. The vetiver fibers were of three mesh sizes (100, 150 and 200 mesh) and the VF concentrations were varied from 0%, 5%, 10%, 15%, 20%, 25% to 30% ww. The results revealed that the VF influenced the density, thermal conductivity and mechanical properties of the VFPU foams. Specifically, the foam density was inversely correlated with the VF concentration, while the thermal conductivity and the VF content were positively correlated. The increase in the VF content contributed to the deterioration of the mechanical properties because of the development of large closed cells. The results also showed that the 200mesh VF was the optimal mesh size due to the lowest thermal conductivity. In fact, all the experimental VFPU foams meet the ASTM C 208 standard, indicating the prospects of mixing the vetiver fibers with polyurethane to produce the environmentallyfriendly thermal insulation foams.

PVDFTrFEBased Stretchable Contact and NonContact Temperature Sensor for ESkin Application Development of stretchable electronics has been driven by key applications such as electronics skin for robotic or prosthetic. Mimicking skin functionalities imposes at a minimal level: stretchability, pressure, and temperature sensing capabilities. While the research on pressure sensors for artificial skin is extensive, stretchable temperature sensors remain less explored. In this work, a stretchable temperature and infrared sensor has been developed on a polydimethylsiloxane substrate. The sensor is based on poly(vinylidene fluoridetrifluoroethylene) (PVDFTrFE) as a pyroelectric material. This material is sandwiched between two electrodes. The first one consists of aluminium serpentines, covered by gold in order to get electrical contact and maximum stretchability. The second one is based on poly(3,4ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) that has shown good electrical compatibility with PVDFTrFE and provides the stretchability of the top electrode. Without poling the PVDFTrFE, sensor has shown a sensitivity of around 7 pF.xc2xb0C1 up to 35% strain without any change in its behaviour. Then, taking advantage on infrared absorption of PEDOT:PSS, a poled device has shown a pyroelectric peak of 13 mV to an infrared illumination of 5 mW at 830 nm. This stretchable device valuably allows an electronic skin (eskin) use for contact and more importantly noncontact thermal sensing.