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ABSTRACT Thermoplastic elastomers (TPEs) have recently emerged as a class of promising precursors of ordered mesoporous carbons (OMCs) due to their low cost and broad availability. Despite understanding their reaction‐induced morphological changes, the fundamental pyrolysis kinetics of crosslinked TPEs remain poorly understood. In this study, we systematically investigate the pyrolysis behavior and pore formation mechanisms of sulfonated polystyrene‐block‐polybutadiene‐block‐polystyrene (SBS) using thermogravimetric analysis coupled with mass spectrometry (TGA‐MS), nitrogen physisorption measurements, and model‐free kinetic analysis. TGA‐MS results reveal a multi‐stage thermal decomposition process characterized by distinct thermal transitions and volatile product evolution. Nitrogen physisorption measurements demonstrate the development of mesoporosity and surface area with increasing pyrolysis temperature, identifying critical thermal windows for mesopore formation. Furthermore, kinetic modeling of the pyrolysis process was used to determine the apparent activation energies for the cleavage of aromatic and unsaturated moieties. These findings can provide important mechanistic insights for material and process design for producing OMCs via direct pyrolysis of commercially available TPEs. 

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 Electrified thermal chemical synthesis plays a critical role in reducing energy consumption and enabling the industrial decarbonization. While Joule heating offers a promising alternative to gas‐burning furnace systems by directly heating substrates via renewable energy supply, most approaches can only heat the reactor, not the catalytic sites. This limitation stems from the lack of methods to on‐demand create Joule heaters containing in situ loaded catalytic nanoparticles. This work introduces a scalable platform for producing carbonaceous Joule heaters embedded with catalytic nanoparticles from 3D‐printed polypropylene precursors, prepared through crosslinking, metal nitration immersion, and pyrolysis steps. Specifically, sulfonate groups on crosslinked PP can bind with metal ions, yielding well‐dispersed, nanosized particles within a carbon structure that maintains macroscopic dimensional accuracy throughout the manufacturing. The approach is modular, allowing control over particle size and composition. Structured carbon with in situ loaded nickel nanoparticles demonstrates efficient Joule heating, high catalytic activity, and significantly reduced activation energy for catalytic ammonia decomposition. This work provides an innovative material and manufacturing platform to produce structured, catalytically active Joule heaters for decarbonization of chemical synthesis and energy production. 

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. 

This review summarizes methods for converting commodity polymers into value-added carbon materials and outlines future opportunities for scaling plastic waste upcycling. 

This study uses contrast matched small angle neutron scattering and simulations to explore how increased pore size in carbon sorbents influences perfluorooctanoic acid adsorption and aggregation, facilitating semi-cylinder micelle formation.