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Abstract Environmental contamination by plastic waste is a growing threat to the environment and human health. Unfortunately, most post‐consumer plastics are still disposed of in landfills, even plastics that could be easily recycled via simple chemical processes. This disconnect between technology and implementation is partly due to the economic barrier posed by multi‐step processes that convert plastic waste into commodity goods. There is an urgent need for green methods to convert plastic waste directly into marketable commodities via simple processes. Herein we report a simple, single‐stage process to chemically recycle poly(ethylene terephthalate) (PET) to yield composites having thermal and mechanical properties that are competitive with commercial structural materials like Portland cement. In this protocol, a mixture of PET and geraniol are heated with elemental sulfur. In this process, transesterification between geraniol and PET with concomitant thiocracking of the PET backbone leads to the formation of a highly‐crosslinked sulfur–PET–geraniol (SPG) network composite. The composite exhibited compressive strength (23.1 MPa) greater than that required for Portland cement to be used in building foundations. This new, single‐stage chemical recycling strategy thus employs a bio‐olefin and waste sulfur to convert PET waste into a durable composite that could serve as a sustainable alternative to traditional cements.
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This content will become publicly available on December 1, 2025
Waste Polyethylene Terephthalate (PET) as a Partial Replacement of Aggregates in Sustainable Concrete
Concrete use is enhanced daily due to infrastructure development, but it has adverse impacts on the environment. Modern lifestyles have led to the increased use of plastic, and, for households, polyethylene terephthalate (PET) plastics are used. However, PET is non-biodegradable and causes adverse impacts on the environment and marine health. So, there is a need to minimize the amount of plastic waste by finding an alternative use for the waste. Our study focuses on creating sustainable concrete by utilizing PET-based plastic waste as a partial substitution for aggregates, aiming to use this concrete for various low-load-bearing construction applications. From our phase analysis study, no adverse effects were found on cement phase formation. We also found that up to 10 wt.% PET incorporation leads to acceptable compressive strength reduction as per ASTM guidelines. To enhance adhesion, the PET was roughened, and, from FESEM, we found effective adhesion of PET waste into the cement matrix. We believe that this sustainable concrete will not only contribute to waste reduction but also promote eco-friendly construction material development.
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- Award ID(s):
- 2415385
- PAR ID:
- 10620928
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Construction Materials
- Volume:
- 4
- Issue:
- 4
- ISSN:
- 2673-7108
- Page Range / eLocation ID:
- 738 to 747
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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