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Abstract While various plastic waste management practices are demonstrated to result in materials with similar properties, morphological features of plastic waste are often lost after recycling/upcycling. Particularly, synthetic textiles are a severely underutilized waste stream that contains built‐in value stemming from their woven architectures. This work demonstrates a simple upcycling strategy to convert polypropylene‐based (PP) woven fabrics to carbon fiber mats through direct pyrolysis for direct use in various end applications without need of additional processing steps, distinct from prior works converting plastic waste to carbon‐based additives. The retention of material properties and architectures, taking advantage of the inherent value with initial product manufacturing, is investigated, with optimal conditions resulting in consistent high carbon yields. Moreover, the textile‐derived carbon shows exceptional Joule heating performance, which can be employed in various heating applications, resulting in reduced energy consumption compared to conventional heating. Furthermore, decoration of fabric‐derived carbon with metal nanoparticles is demonstrated through electroplating, leading to altered surface functionality and further enhanced Joule heating performance. This work introduces a scalable method for upcycling of plastic waste to functional carbons that can completely retain initial material architectures with controlled shrinkage, providing a viable strategy for generating value‐added products toward electrification of heating processes.
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Polymeric Dynamic Crosslinker for Upcycling of Fragile Low-Molecular-Weight Polypropylene
While tremendous progress has been made in the dynamic crosslinking of polypropylene (PP) for plastics upcycling, their efficacy in addressing low molecular weight (MW) PP waste remains untapped. In this work, we demonstrate a simple and scalable method to convert brittle low MW PP to vitrimer materials with enhanced thermal and mechanical properties, enabling their use in circular upcycling. Different from most previous work employing small molecule crosslinkers, we prepare PP vitrimers (PPv) using polymeric crosslinkers, containing polyethylene glycol segments (PEG), which lead to altered crystalline structures and network formation. Importantly, by increasing the MW of crosslinkers from 200 Da to 1000 Da, the PPv exhibit more than 50 times increase in their fracture energy with strong ductility, which can be attributed to combined effects of strengthened amorphous regions of semi-crystalline PP domains and the phase separation between soft PEG segments and PP matrix. Moreover, when blending the PPv with high MW PP (PPh), the PPh/PPv blends show comparable elastic modulus, yield strength, and stretchability to the PPh, in sharp contrast to the widely-known embrittlement of low MW PP/PPh blends. These results demonstrate the use of polymeric dynamic crosslinkers as an important strategy for upcycling low MW PP waste to value-added products.
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- Award ID(s):
- 2211573
- PAR ID:
- 10503522
- Publisher / Repository:
- American Chemical Society
- Date Published:
- Journal Name:
- ACS Applied Polymer Materials
- Volume:
- 5
- Issue:
- 6
- ISSN:
- 2637-6105
- Page Range / eLocation ID:
- 4056 to 4068
- Subject(s) / Keyword(s):
- polyolefin, vitrimers, crystallinity, circular economy, structure-property relationship
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsapm.3c00289
