Green polymeric composites based on construction and packaging waste: toward advanced insulating materials

Area of Science:

• Materials Science
• Polymer Science
• Waste Management

Background:

• Developing sustainable composite materials is crucial for reducing environmental impact.
• Waste materials like polystyrene, sawdust, red brick, and ceramic waste offer potential as low-cost fillers.
• Characterizing waste materials is essential to determine their suitability as composite reinforcements.

Purpose of the Study:

• To explore the development of sustainable polymeric composites using waste polystyrene (WPS) as a matrix.
• To investigate the effects of sawdust (SD), red brick waste (RbW), and ceramic waste (CW) as hybrid fillers on composite properties.
• To evaluate the potential of these waste-derived fillers for enhancing mechanical, thermal, and electrical characteristics.

Main Methods:

• Composites were prepared with varying weight percentages (0-40%) of WPS and hybrid fillers (SD, RbW, CW).
• X-ray fluorescence (XRF) and Transmission Electron Microscopy (TEM) characterized filler composition and particle size.
• Mechanical testing (tensile strength, elongation at break), water absorption tests, Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA), and dielectric measurements were performed.

Main Results:

• XRF confirmed high SiO2 and Al2O3 content in CW and RbW, while SD is organic. TEM showed nano-sized inorganic waste particles.
• Tensile strength increased with hybrid fillers, peaking at 25.45 MPa for WPS/CW composites.
• Water absorption decreased with increased demolition waste content, particularly for WPS/CW composites.
• WPS/CW composites exhibited enhanced thermal stability, higher glass transition temperature (Tg), and improved dielectric properties (higher permittivity, lower dielectric loss).

Conclusions:

• Waste polystyrene reinforced with industrial wastes like ceramic waste shows significant potential for sustainable composite development.
• Ceramic waste is a highly effective filler, enhancing mechanical strength, thermal stability, and electrical insulation properties of polystyrene composites.
• These findings suggest a viable route for valorizing industrial waste streams into functional composite materials for various applications.