Characterization of new composite material based on date palm leaflets and expanded polystyrene wastes

In the aim of environmental protection and valorization of vegetal resource, an experimental study on an innovative Wood-Plastic Composite material (WPC) based on Date Palm and expanded Polystyrene, EPS, Wastes is performed. Date palm leaflets waste are used as the reinforcement and EPS waste dissolved in gasoline is used as a matrix. Several combinations of reinforcement sizes (0.1-0.315 mm, 0.315-0.5 mm and 0.5-1 mm) and fiber-to-matrix weight ratios (70, 75 and 80 wt%) were considered to investigate the properties of the Leaflets-Polystyrene Composite (LPC). In this study, physical, mechanical, thermal and morphological characterizations were carried out in order to determine: the bulk density, the flexural modulus, the maximum stress and the thermal conductivity of LPC. Therefore, Pycnometer density measurement, three-point bending test were performed and transient plane heat source (hotdisc) method was used. Furthermore, a characterization by scanning electron microscopy (SEM) was realized to observe the fibers/matrix bond. The LPC showed good adhesion state of the fiber-matrix interface and acceptable mechanical properties with a flexural modulus and a maximum stress that can achieve 0.78 GPa and 2.84 MPa, respectively. The LPC has a density between 542 and 824 kg/m3 which are comparable to those of usual materials like hard-and-soft wood, MDF and other WPC found in the literature. The thermal characterization tests of the LPC have shown also an average thermal conductivity within the range of 0.11 and 0.16 W/m·K. The LPC can be used in the field of building construction as a good thermal insulation as well as a structural component in sandwich structures. Moreover, LPC material is obtained from wastes and can be totally recycled at the end of its useful life.