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Abstract Chlorinated plastics are part of the everyday lives of consumers and producers alike. They can be found in buildings, automobiles, fashion, packaging, and many other places. This prevalence makes them a considerable part of the plastic waste crisis. Interest in “upcycling” (as opposed to recycling) has grown recently to augment the possibilities of managing plastic waste. The advances made in plastic upcycling have focused on polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET) and polystyrene (PS) while chlorinated plastics, chiefly polyvinyl chloride (PVC), have received much less attention. The release of chlorine‐containing molecules during treatment of chlorinated plastic greatly complicates cross‐method upcycling, or even the treatment of plastic mixes containing chlorinated plastics. This review presents a case for extracting value from chlorinated plastics by highlighting appealing upcycling products made owing to, or despite, the C‐Cl bond via depolymerization, carbonization and modification. This article is protected by copyright. All rights reserved.
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Plastic Composites from Repurposed Poly(ethylene terephthalate) Wasted Functionalized Graphene Oxide through Dynamic Depolymerization
Plastic upcycling, which involves making plastic-derived products with unique or improved properties from discarded plastic materials, is a promising alternative to recycling and disposal to help reduce the overall production of waste. However, recycled and reused materials typically have inferior mechanical, thermal, optical, and barrier properties compared with virgin plastics. Upcycled plastic materials could improve these properties while addressing future waste accumulation. In this study, we use waste poly(ethylene terephthalate) (PET) collected from disposable food packaging to create a repurposed plastic graphene oxide (GO) composite with a goal of upcycling. We developed a one-pot “dynamic depolymerization” to break down PET in the presence of GO and successfully enabled transesterification of the polymer onto GO. Covalent attachment of PET onto GO and tailorable plastic content was confirmed by thermogravimetric analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. These covalent composites (PET-GO) were found to be relatively impermeable to water vapor, showing promise for applications in packaging materials. Aqueous degradation experiments on the composite materials demonstrated that, in bulk conditions, PET-GOs remain mechanically robust while in contact with water over appropriate time scales for packaging applications, while beginning to break down in accelerated conditions. The use of depolymerization methods to promote polymer grafting concurrently with polymer deconstruction could provide a more general method for grafting waste polymers onto oxidized carbonaceous substrates with further study.
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- Award ID(s):
- 2318652
- PAR ID:
- 10534394
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Nano Materials
- Volume:
- 7
- Issue:
- 4
- ISSN:
- 2574-0970
- Page Range / eLocation ID:
- 3691 to 3701
- Subject(s) / Keyword(s):
- Graphene Oxide Upcycling Depolymerization Poly(Ethylene Terephthalate) Composite
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsanm.3c05131
