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Complex Star Architectures of Well-Defined Polyethylene-Based Co/Terpolymers
Abstract not provided
Could Superficial Chiral Nanostructures Be the Reason Polyethylene Yellows as It Ages?
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Preparation and Characterization of Polyethylene Copolymers with PAH Side Groups as Carbon Fiber Precursors
Not provided.
Catalytic Hydrogenolysis of Polyethylene Under Reactive Separation
Deconstruction of polyolefins by catalytic hydrogenolysis is typically accompanied by the generation of undesired light gases. At reaction temperatures, the desired liquid products also tend to be volatile. Secondary cleavage of these liquid products contributes to light gas formation. The latter process was mitigated by reactive separation, continuously separating the liquid products from the catalyst throughout the experiment. At equivalent conversion, the yield and selectivity for oligomeric liquid species are increased under reactive separation, even though the carbon–carbon bond cleavage rate is slower than that in sealed experiments. More light gas is formed in the sealed reactor. Under 1 atm H 2 partial pressure, alkenes accompany the typical alkane hydrogenolysis products. Further, the alkene yield is higher, with greater selectivity for valuable α-olefins under reactive separation. These results provide the mechanistic insight that terminal alkenes are primary products of carbon–carbon bond cleavage during hydrogenolysis under experimental conditions, and secondary deconstruction of these species produces light gases.
Tracking Chain Populations and Branching Structure during Polyethylene Deconstruction Processes
Not Available
Suppressing Crossover in Nonaqueous Redox Flow Batteries with Polyethylene-Based Anion-Exchange Membranes
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Systems Analysis Approach to Polyethylene Terephthalate and Olefin Plastics Supply Chains in the Circular Economy: A Review of Data Sets and Models
The environmental and economic impacts of implementing a circular economy in plastic waste supply chains are not well understood. The proposed systems analysis framework assesses environmental, social, and economic impacts of plastic waste supply chains in a circular economy. The first objective of this article is to identify datasets, models and knowledge gaps associated with waste plastic supply chain processes, mainly in the U.S. Our literature review indicated that the best datasets exist for virgin plastic resin production, mechanical recycling, landfilling, and incineration, with materials recovery facility being intermediate, and with chemical recycling the lowest. The second objective of this article is to develop an illustrative application of the framework by conducting a preliminary systems analysis of PET bottles with closed-loop recycling. Here, the preliminary systems analysis of PET bottles utilized a linear programming optimization method. Our optimization model indicated that both chemical and mechanical recycling processes are needed to achieve a true circular economy of PET bottles with the least greenhouse gas emissions, specifically reductions of 24% when compared with the linear economy. Good quality and standardized life cycle assessment and techno-economic analysis studies are needed to better understand the environmental, economic, and social impacts of advanced sorting and chemical recycling technologies.
Chemical Upcycling of Polyethylene to Value-Added α,ω-Divinyl-Functionalized Oligomers
Not provided.
Controlling Product Distribution of Polyethylene Hydrogenolysis Using Bimetallic RuM 3 (M = Fe, Co, Ni) Catalysts
Not Available