Mechanical and Tribological Behavior of Reinforced Polypropylene: Mineral Bio-Based Filler Approaches

Polypropylene (PP) is widely used in engineering applications due to its low density, chemical resistance, processability and favorable cost-to-performance ratio. This book investigates the mechanical and tribological behavior of PP composites containing talc and almond-shell particles, with emphasis on filler content and particle size.The first system consists of PP filled with 5, 10, and 50 wt.% talc and tested under dry reciprocating sliding against steel. Friction, wear, and worn-surface morphology are analyzed at different sliding durations. Low and intermediate talc contents provide relatively stable friction, whereas 50 wt.% talc causes pronounced friction fluctuations and increased wear, with adhesive interaction, plowing, micro-cutting, debris formation, third-body abrasion, and localized delamination observed.The second system uses 5, 10, and 15 wt.% almond-shell particles with sizes of 600-900 and 400-600 ¿m. Almond-shell incorporation increases hardness and tensile modulus, while tensile strength and ultimate strain decrease. Particle size and content significantly affect friction and wear, with the D2-15 formulation providing a favorable balance of stiffness and wear.