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Incorporating degradable linkages into polyolefin backbones offers a promising route toward sustainable alternatives. For semicrystalline degradable polyolefins, understanding the impact of such linkages on their crystallization behaviors is important, since the crystallization process governs their morphology formation and thus dictates mechanical and thermal performance. Here, we studied the crystallization behaviors of degradable polyethylene (PE) mimics containing sparsely inserted ester linkages along the polymer backbone, which exhibit comparable mechanical and thermal properties to conventional PE. Two systems, HDPE-DM and LLDPE-DM, were investigated and compared with their commercial, non-degradable counterparts under isothermal and non-isothermal conditions. We found that ester incorporation does not alter the thermodynamics of the perfect crystal. However, relative to the non-degradable PE mimics (HDPE-M), the presence of ester linkages accelerates crystallization kinetics by reducing the overall crystallization activation energy and promoting chain folding. The crystallization activation energy of HDPE-DM was comparable to that of commercial HDPE, indicating that ester linkages can be introduced in polymer backbones without significantly impacting their crystallization behaviors and thus relevant industrial manufacturing processes. These findings provide new insights into how degradable linkages influence crystallization in degradable PE materials, which may inform the design and process of sustainable polyolefin materials with a balanced performance and recyclability. 

This work presents an integrated approach to industrial decarbonization by converting mixed polyolefin waste into structured carbon with exceptional Joule heating properties, enabling efficient electrified hydrogen productionviaNH₃decomposition. 

Abstract Förster resonance energy transfer (FRET) is an established tool for measuring distances between two molecules (donor and acceptor) on the nanometer scale. In the field of polymer science, the use of FRET to measure polymer end‐to‐end distances (R_ee) often requires complex synthetic steps to label the chain ends with the FRET pair. This work reports an anthracene‐functionalized chain‐transfer agent for reversible addition‐fragmentation chain‐transfer (RAFT) polymerization, enabling the synthesized chains to be directly end‐labeled with a donor and acceptor without the need for any post‐polymerization functionalization. Noteworthily, this FRET method allows for chain conformation measurements of low molecular weight oligomers in situ, without any work‐up steps. Using FRET to directly measure the averageR_eeof the oligomer chains during polymerization, the chain growth of methyl methacrylate, styrene, and methyl acrylate is investigated as a function of reaction time, including determining their degree of polymerization (DP). It is found thatDPresults from FRET are consistent with other established measurement methods, such as nuclear magnetic resonance (NMR) spectroscopy. Altogether, this work presents a broadly applicable and straightforward method to in situ characterizeR_eeof low molecular weight oligomers and theirDPduring reaction. 

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

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.