Abstract

Background: Rapid growth in the generation of electronic waste (e-waste) is a serious issue and consistent efforts are being made worldwide towards sustainable developments in material recovery, recycling and waste management.

Objective: In this article, we report on the utilization of the polymeric fraction from waste printed circuit boards (PCBs) as reinforcing filler in polypropylene (PP) composites.

Method: Composites were prepared by melt blending PP with varying amounts of PCB waste ranging from 0 to 25 wt. %. Mechanical and rheological properties of PP composites were investigated.

Results: The incorporation of PCB waste increased the tensile modulus, the flexural strength and the flexural modulus of composites by 38, 31 and 93% respectively; however the tensile strength was found to decrease by 12%. PP/PCB waste composites showed good resistance to impact as the notched impact strength of composites showed a marginal decrease of 19% for up to 15 wt. % loading and became constant for higher waste loadings. An optimum in mechanical properties was achieved at 25 wt. % PCB waste loading. Glass fiber pull out from the PP matrix was found to act as an effective energy dissipation mechanism during impact. Elastic and viscous moduli of the composites increased approximately by 6 and 2 times respectively than PP alone. The complex viscosity modulus value increased by around 7 times at high shear rate as compared to pure PP, while still remaining well within the acceptable limits for molding processes.

Conclusions: This study has helped develop an environment friendly route for utilizing polymeric electronic waste.

Keywords: E-waste, polymer composites, polypropylene, reinforcing fillers, recycling, mechanical, rheological properties.

Graphical Abstract