Waste Eggshells as a Natural Filler for the Poly(Vinyl Chloride) Composites

Area of Science:

• Materials Science
• Polymer Science
• Sustainable Materials

Background:

• Unplasticized polyvinyl chloride (PVC) is a widely used thermoplastic.
• Developing sustainable fillers for polymer composites is crucial for environmental impact reduction.
• Waste eggshells represent an abundant, low-cost, and potentially valuable bioresource.

Purpose of the Study:

• To characterize unplasticized PVC composites modified with biofiller derived from waste hen eggshells.
• To evaluate the effect of eggshell biofiller on the processing, mechanical, thermal, and structural properties of PVC.
• To assess the feasibility of using ground eggshells as an effective filler for PVC composites.

Main Methods:

• Composites were prepared by extruding PVC with 10-40 phr of ground eggshell biofiller.
• Filler characterization included SEM, TG, and sieve analysis.
• Material properties were assessed using plastographometry, MFR, Charpy impact strength, tensile testing, DMTA, TGA, SEM, and micro-CT.

Main Results:

• The addition of eggshell biofiller did not negatively impact the processability of PVC composites.
• Significant improvements were observed in thermal stability, modulus of elasticity, and Vicat softening point (VST).
• Eggshells acted as radical scavengers, delaying PVC degradation and enhancing material durability.

Conclusions:

• Ground hen eggshells are an effective and sustainable biofiller for unplasticized PVC composites.
• The modified composites exhibit enhanced thermal and mechanical performance compared to neat PVC.
• This research supports the valorization of waste eggshells into functional materials for polymer applications.