Closed-loop recycling of polyethylene-like materials
نویسندگان
چکیده
Plastics are key components of almost any technology today. Although their production consumes substantial feedstock resources, plastics largely disposed after service life. In terms a circular economy1–8, reuse post-consumer sorted polymers (‘mechanical recycling’) is hampered by deterioration materials performance9,10. Chemical recycling1,11 via depolymerization to monomer offers an alternative that retains high-performance properties. The linear hydrocarbon chains polyethylene12 enable crystalline packing and provide excellent properties13. Their inert nature hinders chemical recycling, however, necessitating temperatures above 600 degrees Celsius recovering ethylene with yield less than 10 per cent3,11,14. Here we show renewable polycarbonates polyesters low density in-chain functional groups as break points in polyethylene chain can be recycled chemically solvolysis recovery rate more 96 cent. At the same time, do not disturb structure, desirable properties (like those high-density polyethylene) fully retained upon recycling. Processing performed common injection moulding well-suited for additive manufacturing, such 3D printing. Selective removal from model polymer waste streams possible. our approach, initial result polycondensation long-chain building blocks, derived state-of-the-art catalytic schemes plant oil feedstocks, or microalgae oils15. This allows closed-loop recycling polyethylene-like materials. Polycarbonates like constituent monomers, re-polymerization yielding material uncompromised processing
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ژورنال
عنوان ژورنال: Nature
سال: 2021
ISSN: ['1476-4687', '0028-0836']
DOI: https://doi.org/10.1038/s41586-020-03149-9