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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. 

Carbon dioxide hydrogenation with base to generate formate salts can provide a means of storing hydrogen in an energy dense solid. However, this application requires catalytic CO2 hydrogenation, which would ideally use an earth abundant metal catalyst. In this article, six new (CNC)CoIL2 pincer complexes were synthesized and fully characterized, including single crystal X-Ray diffraction analysis on four new complexes. These complexes contain an imidazole-based (1R) N-heterocyclic carbene (NHC) ring or a benzimidazole based NHC ring (2R) in the CNC pincer. The R group is para to N on the pyridine ring and been varied from electron withdrawing (CF3) to donating (Me, OMe) substituents. The L type ligands have included CO and phosphine ligands (in PPh32 and PMe32). Thus, two known Co complexes (1, 1OMe) and six new complexes (1Me, 1CF3, 2, 2OMe, PPh32, PMe32) were studied for the CO2 hydrogenation reaction. In general, the unsubstituted CNC pincer complexes bearing two carbonyl ligands led to the highest activity. The best catalyst, 2, remains active for over 16 h and produces a turnover number of 39,800 with 20 bars of 1:1 CO2 / H2 mixture at 60 °C. A computational study of the mechanism of CO2 hydrogenation is also reported.