The food industry's ever‐increasing need to substitute synthetic packaging materials has led to the development of eco‐friendly alternatives with improved physical and mechanical properties. The main objective of this work relates to the effect of adding different weight fractions (1, 3 and 5 wt%) of cellulose nanocrystals (CNC) and cellulose nanofibrils (CNF) on the morphological, thermal, structural, biodegradable and mechanical properties of PVA/Chitosan (CS) bio‐nanocomposites. The DSC and FTIR results reveal that PVA and Chitosan are compatible due to the strong interactions via hydrogen bonding, which are also proved by the tensile test. The water solubility test indicates the biodegradability of nanocomposites. Furthermore, CNF have significantly enhanced the mechanical properties of PVA/CS. Hence, PVA/CS/CNF nanocomposites can be efficiently utilized for bio‐based packaging materials, where good mechanical properties are prime requirements.

Surface acoustic wave (SAW) strain sensors require an adhesive - typically a glue - for the mounting on the part under measurement. This comes with strain-transfer, reproducibility and aging issues. In this paper, we propose a novel glue-less solution where the SAW sensor is directly fabricated onto the surface of interest, here a metallic substrate. Here, we study the layered structure ZnO/Ti numerically and experimentally, with ZnO as the piezoelectric layer and titanium as the substrate. In this structure, both BAW (Bulk Acoustic Waves) and SAW can propagate, and we used both of them to monitor temperature variations up to 300°C and strain levels up to 1800 με. Moreover, reflective delay line (R-DL) designs were used, to provide the future users with RFID functionalities. In order to overcome the limitations due to the relatively low electromechanical coupling coefficient of ZnO/Ti, a specific R-DL layout with connected inter digital transducers (IDTs) was used. The obtained-experimental results confirm that the proposed glue-less R-DL structure is a promising solution for the independent evaluation of temperature and strain, with identification.