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Abstract As the demand for clean water intensifies, developing effective methods for removing pollutants from contaminated sources becomes increasingly crucial. This work establishes a method for additive manufacturing of functional polymer sorbents with hollow porous features, designed to enhance interactions with organic micropollutants. Specifically, core–shell filaments are used as the starting materials, which contain polypropylene (PP) as the shell and poly(acrylonitrile‐co‐butadiene‐co‐styrene) as the core, to fabricate 3‐dimensional (3D) structures on‐demand via material extrusion. After 3D printing, the cores of the printed roads are removed through solvent extraction, creating hollow structures that increase accessible surface area for adsorption. Subsequently, a sulfonation‐induced crosslinking reaction installs sulfonic acid functionalities into the PP backbones, while enhancing their chemical stability. It is found that larger voids, and thinner polymer shells, enable improved structural retention during the sulfonation through limiting reaction‐induced stresses. The hollow sulfonated PP sorbents exhibit a strong affinity against cationic pollutants. Specifically, larger voids within these structures not only improve structural integrity but also result in accelerated adsorption kinetics by maximizing accessible surface area, thereby enhancing pollutant removal efficiency. This work provides a promising solution for advanced structured sorbent fabrication with hollow architectures, leading to more effective solutions for water contaminant removal in the future. 

Abstract Despite groundbreaking advances in the additive manufacturing of polymers, metals, and ceramics, scaled and accurate production of structured carbons remains largely underdeveloped. This work reports a simple method to produce complex carbon materials with very low dimensional shrinkage from printed to carbonized state (less than 4%), using commercially available polypropylene precursors and a fused filament fabrication-based process. The control of macrostructural retention is enabled by the inclusion of fiber fillers regardless of the crosslinking degree of the polypropylene matrix, providing a significant advantage to directly control the density, porosity, and mechanical properties of 3D printed carbons. Using the same printed plastic precursors, different mechanical responses of derived carbons can be obtained, notably from stiff to highly compressible. This report harnesses the power of additive manufacturing for producing carbons with accurately controlled structure and properties, while enabling great opportunities for various applications. 

Abstract Controlling the self‐assembly behaviors of block copolymers (BCPs) is a focal point of many research thrusts due to their broad use in various applications. While BCP molecular weight, volume fraction, and chemical identities are key thermodynamic parameters to determine their morphology, an emergent method in this area is through reaction‐induced changes to the characteristics of a BCPin situ, which provides access to multiple morphologies and domain sizes from a single parent polymer, as well as enabling the formation of metastable morphologies which may be difficult to attain otherwise. This work provides a focused review about the current state of reaction‐induced morphology control in BCPs in both solution and solid states. Furthermore, we provide a forward‐looking perspective on the future opportunities of understanding and employing reaction engineering to manipulate and advance BCP self‐assembly. © 2023 Society of Industrial Chemistry. 

Abstract While various plastic waste management practices are demonstrated to result in materials with similar properties, morphological features of plastic waste are often lost after recycling/upcycling. Particularly, synthetic textiles are a severely underutilized waste stream that contains built‐in value stemming from their woven architectures. This work demonstrates a simple upcycling strategy to convert polypropylene‐based (PP) woven fabrics to carbon fiber mats through direct pyrolysis for direct use in various end applications without need of additional processing steps, distinct from prior works converting plastic waste to carbon‐based additives. The retention of material properties and architectures, taking advantage of the inherent value with initial product manufacturing, is investigated, with optimal conditions resulting in consistent high carbon yields. Moreover, the textile‐derived carbon shows exceptional Joule heating performance, which can be employed in various heating applications, resulting in reduced energy consumption compared to conventional heating. Furthermore, decoration of fabric‐derived carbon with metal nanoparticles is demonstrated through electroplating, leading to altered surface functionality and further enhanced Joule heating performance. This work introduces a scalable method for upcycling of plastic waste to functional carbons that can completely retain initial material architectures with controlled shrinkage, providing a viable strategy for generating value‐added products toward electrification of heating processes. 

The heat effect of nonthermal plasma significantly enhanced the synergy between the plasma and the catalytically active sites. Consequently, nearly 100% NH₃decomposition was achieved over the low-loading Ru/Al₂O₃catalyst under adiabatic conditions. 

This work demonstrates a straightforward method to convert real-world shoe waste midsoles into water remediation sorbents for the removal of cationic organic pollutants. 

This work demonstrates a series of functionalization methods to enhance the utility of thermoplastic-elastomer derived ordered mesoporous carbons, including chemical activation, heteroatom doping, and the introduction of nanoparticles. 

This work demonstrates a simple method to prepare hierarchically porous materials. The introduction of macropores in mesoporous matrix enables its improved sorbent performance against pollutants for water remediation.