The influence of pistachio shell addition on the mechanical behavior of self-curing PMMA composites

Recently, due to their outstanding mechanical and biological properties, natural fiber composites are widely utilized in various applications for limiting or replacing synthetic fiber composites. Hence, in the current research, different average grains sizes of the back (75 µm, 150 µm, 212 µm and 300 µm) with self-cured poly methyl methacrylate (PMMA) have been produced. Several mechanical examinations such as compression, impact, flexural, and tensile tests were carried out, and the effect of adding different weight fractions of about 10, 20, and 30 wt%. The tensile results showed that the strengths increased the highest values at (≤ 150 µm) PS were 69 MPa at 10 wt%, while the tensile strength declined when each of exceeds this particle sizes and as increasing the weight fraction of pistachio shells powders in composite materials. Consequently, the modulus of elasticity increased as the weight fraction of pistachio shell powders in PMMA resin increased, with PS having the greatest value (30 wt%) and the largest average particle size (75 m). For all particle sizes, the compression strength increased as the weight percentage of pistachio shell powders in PMMA matrix rises. However, at 30 wt% and an average particle size of about 150 m, their maximum values were discovered. Despite the fact that the lowest values were found at 10% weight and 96 MPA for the average particle size (300 m), they are still greater than the compression strength of pure PMMA. Besides, the study reveals that the impact strength increased with the rise in the pistachio shells powders contents (wt%) in PMMA matrix where the highest value in 20 wt% and (≤ 150) µm average particles sizes of PS was 2.5 kJ/m 2 . Furthermore, there is a decrease in flexural strength when increasing the fractional weights of pistachio shell powders in polymer resin.