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Abstract Plastic transformations are critical to ongoing recycling and upcycling efforts, but the complexity of the reactions makes it difficult to understand the effect of individual factors on reaction rates and product distributions experimentally. In this work, we report on a multiscale simulation framework for studying polymer transformations that incorporates affordable high‐level coupled cluster calculations combined with benchmarked density functional theory calculations, detailed conformer search, and lattice‐based kinetic Monte Carlo simulations to provide the temporal and spatial evolution of the polymer during transformations. Our framework can match experimentally observed reaction times within an order of magnitudewithoutany parameter estimation in base‐assisted dehydrochlorination of polyvinyl chloride. We determine that the E2 reaction mechanism dominates the reaction and demonstrate that different structural defects can inhibit or promote directional polyene growth as well as affect the structure of the dehydrochlorination product. 

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. 

Plastic is ubiquitous across all aspects of modern life. Despite its usefulness, only 9% of all plastic waste ever produced has been recycled, leaving a tremendous amount that ends up in landfills and the environment. New strategies need to investigate using this waste plastic. This report analyzes upcycling waste plastics into membranes for water and gas separations. Polyethylene terephthalate, polystyrene, poly(vinyl chloride), polyethylene, polypropylene, and tire rubber have been studied for use as membranes. Future work needs to investigate greener solvents, health and safety aspects, costs, supply and demand, and life cycle assessments for upcycling plastic waste into membranes. 

The drive towards a circular economy in plastic materials has become a worldwide goal. 

In this study, a three-dimensional off-lattice kinetic Monte Carlo-Molecular Dynamics (KMC-MD) simulation framework [Comp. Mat. Sci. 229, 112421 (2023)] is used to investigate the dehydrochlorination/conjugation transformation of polyvinyl chloride (PVC) in sodium hydroxide (NaOH) with atomistic resolutions at experimental timescales (103 – 106 s). Our framework enables an examination of the competing reaction pathways and molecular-scale changes influenced by various solvents (acetone, ethylene glycol, triethylene glycol, tetrahydrofuran, and bio-derived solvents), as well as the influence of varying molecular weight distributions, NaOH concentrations, and temperatures. The algorithm simulates bond cleavage and formation during the KMC stages, whereas the MD stage is dedicated to the relaxation and thermalization of the PVC-NaOH-solvent system. The framework allows us to capture important configurational aspects (mixing, correlations, clustering, etc.) that are not accessible with a traditional microkinetic model, and it potentially allows us to perform benchmarking at experimental timescales. 

Quantum tunnelling drives chloride leaching from polyvinyl chloride to water offering new insights into plastic degradation and transformation processes. 

In our prior study [Olowookere, F. V.; Turner, C. H. J. Phys. Chem. B 2023, 127(42), 9144–9154], we introduced a new scaling relationship to predict gas solute diffusion at challenging conditions, focusing on CO2 and SO2 diffusion in multivalent ionic liquid (IL) solvents. This work extends our initial exploratory study into a much broader array of systems, encompassing additional solutes (N2, CH4, C2H6, C3H8, C3H8O, and H2O) and a variety of different ionic liquid species ([Bzmim3]3+, [Bzmim4]4+, [BMIM]+, [EMIM]+, [HMIM]+, [NapO2]2–, [BzO3]3–, [BF4]−, [Tf2N]−, and [PF6]−). Our study demonstrates a remarkably robust logarithmic correlation between solute diffusion and solvent accessible surface area (SA) across 20 different additional systems. We perform comprehensive analyses of the underlying molecular phenomena responsible for this correlation, including solute lifetime distributions, void space dynamics, and Voronoi tessellation, in order to elucidate a stronger mechanistic understanding of this behavior. Our findings highlight a direct link between the solvent accessible SA and the size of the void domains. Overall, our scaling approach provides an efficient and reliable approach for predicting diffusion from analyses of short simulations at higher temperatures.