Investigation of glass-fiber reinforced polypropylene properties dependence on post-consumer recycled polypropylene content
Anna BORTOLETTO, Matteo MICHELINI, Luca GAZZOLA, Adrian L. KELLY, Ben R. WHITESIDE, Marco SORGATO, Giovanni LUCCHETTA
Abstract. Polymer composites like glass fiber-reinforced polypropylene (GFRP) are widely used for their strength and lightweight properties, but their limited recyclability has raised significant sustainability challenges. This study explores the potential to improve the sustainability of GFRP composites by adding post-consumer recycled polypropylene (rPP). The impact of rPP and specifically of titanium dioxide (TiO₂), found in rPP as a residue of white inks, is evaluated. Two material sets were analyzed: one with varying rPP percentages and one with different TiO₂ levels intentionally added to virgin PP. Mechanical and rheological properties were evaluated through tensile and impact strength, DSC, TGA, SEM, and fiber length measurements. Results revealed TiO₂ contamination reduces fiber length, contributing to mechanical performance degradation. The findings highlight TiO₂’s significant role in recycled GFRP performance and emphasize improving recycling processes to enhance sustainability.
Keywords
Circular Economy, Sustainability, Fiber-Reinforced Plastic, Post-Consumer Recycling, Polypropylene
Published online 9/10/2025, 9 pages
Copyright © 2025 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: Anna BORTOLETTO, Matteo MICHELINI, Luca GAZZOLA, Adrian L. KELLY, Ben R. WHITESIDE, Marco SORGATO, Giovanni LUCCHETTA, Investigation of glass-fiber reinforced polypropylene properties dependence on post-consumer recycled polypropylene content, Materials Research Proceedings, Vol. 57, pp 2-10, 2025
DOI: https://doi.org/10.21741/9781644903735-1
The article was published as article 1 of the book Italian Manufacturing Association Conference
Content from this work may be used under the terms of the Creative Commons Attribution 3.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
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