Responsible disposal of vehicles at the end of life is a pressing environmental concern. In particular, waste plastic forms the largest proportion of non-recycled waste material from light-duty vehicles, and often ends up in a landfill. Here we report the upcycling of depolluted, dismantled and shredded end-of-life waste plastic into flash graphene using flash Joule heating. The synthetic process requires no separation or sorting of plastics and uses no solvents or water. We demonstrate the practical value of the graphene as a re-inforcing agent in automotive polyurethane foam composite, where its introduction leads to improved tensile strength and low frequency noise absorption properties. We demonstrate process continuity by upcycling the resulting foam composite back into equal-quality flash graphene. A prospective cradle-to-gate life cycle assessment suggests that our method may afford lower cumulative energy demand and water use, and a decrease in global warming potential compared to traditional graphene synthesis methods.
Options for recycling fiber composite polymer (FCP) materials are scarce, as these materials cannot be normally recycled and are toxic when improperly disposed. Additionally, reducing water usage is an increasing concern, as the concrete industry currently uses 10% of the world’s industrial water. Therefore, building upon our previous work, this research explores the use of polymer hybrid carbon and glass composite waste products as reinforcements in high-pressure compacted cement. Our material used nearly 70% less water during manufacturing and exhibited improved durability and salt corrosion resistance. Compression strength tests were performed on high-pressure compacted materials containing 6.0 wt% recycled admixtures before and after saltwater aging, and the results showed that the material retained 90% of its original compression strength after aging, as it contained fewer pores and cavities. Our experimental work was supplemented by molecular dynamics. Simulations, which indicated that the synergetic effects of compaction and FCP admixture addition slowed the diffusion of corrosive salt ions by an average of 84%. Thus, our high-pressure compacted cement material may be suitable for extended use in marine environments, while also reducing the amount of commercial fiber composite polymer waste material that is sent to the landfill.
Fiber composite waste more » High-pressure compacted cement samples containing 6% recycled admixtures retained 90% of their compression strength after salt aging. The high-pressure compaction method utilized 70% less water during specimen fabrication.
Fiber composite waste more »
High-pressure compacted cement samples containing 6% recycled admixtures retained 90% of their compression strength after salt aging.
The high-pressure compaction method utilized 70% less water during specimen fabrication.
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