Eco-friendly recycled polypropylene matrix composites incorporated with geopolymer concrete waste particles

Abstract

Civil construction wastes have been incorporated into polymers for recycling as novel engineering composites. In the present work eco-friendly composites with recycled polypropylene (rPP) matrix incorporated with geopolymer concrete waste particles, wither plain (GCW) or surface-modified with oleic acid (AGC) were investigated. The geopolymer concrete waste particles were mixed with polymer powder to provide an effective dispersion between the different materials. Composites were produced by an initial reactive extrusion processing followed by injection molding. These novel composites with amount of 20, 40 and 50 wt% of GCW particles, both plain as-received and surface-modified, were technically evaluated by tensile tests, statistically analyzed by ANOVA, as well as by water absorption as per ASTM standards. Surface dispersion of nanoparticles was revealed by atomic force microscopy. Microstructural analysis was performed by scanning electron microscopy. The results indicated that these sustainable GCW particles incorporated into rPP matrix exhibit superior processability and water absorption less than 0.01%. The rPP/AGC composites present relatively higher elastic modulus, 629 MPa, as compared to the neat rPP, with 529 MPa. These properties suggest potential sustainable applications in building construction using waste materials.

Keywords

• Geopolymer waste
• Recycled polypropylene
• Eco-friendly composites
• Water absorption
• Tensile properties