This work is devoted to investigate the available agricultural Tunisian waste: the date pits as reinforcing filler for thermoplastic matrix. The chemical composition of this reinforcing filler is found to be comparable to nonwood plants: its content comprises of 13% of extractibles, 22% of lignin, and 61% of holocellulose. Then, the lignocellulosic filler was used to prepare different composites films using Brabender mixing device. A series of composite film was established by different loadings of the date pits waste with 10–50% of the filler in 10% as an interval. The ensuing composites materials were then characterized by several techniques such as the morphology of the composites, which was investigated using scanning electron microscopy. The thermal properties of prepared materials were studied using differential scanning calorimetry and thermogravimetric analysis. Finally, the mechanical and water absorption properties were involved. The obtained results indicated that date pits–based particles enhanced the thermomechanical properties of the thermoplastic matrix and demonstrated that this available lignocellulosic biomass can be considered to be a promising filler material.

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A novel highly sensitive Ag-nanocomposite for humidity detection has been successfully prepared. Initially, cellulose isolated from Tunisian palm date petiole was converted to carboxymethyl cellulose (CMC) as biomatrix under heterogeneous conditions. The synthesized product was thoroughly characterized by means of FT-IR spectroscopy, viscosity analysis, and high performance size exclusion chromatography multiangle laser light scattering. CMC was used as reducing and stabilizing agent to prepare CMCstabilized silver nanoparticles via a rapid green method. The bioreduction of silver ions under different experimental conditions, including Ag 1 concentration and pH, was investigated. Optimal experimental conditions provided a long-term stable colloidal suspension and well-dispersed spherical shape Ag NPs with a size ranging from 13 to 28 nm. Ag-nanocomposite coated quartz microbalance crystal was used as sensitive layer for humidity detection. A comparative study showed that the immobilized metallic nanostructures greatly reduced changes in visco-elastic properties, increased surface area as well as surface local charge density of the CMC. Consequently, sensor performances were greatly enhanced: better stability even at higher relative humidity (RH), good reproducibility and linearity (11-98% RH), low hysteresis characteristics, and rapid response and recovery times (14 and 6 s, respectively) were obtained.