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Shape-programmable polymer networks derived from waste elemental sulfur hold great potential for diverse applications such as 4D printing and soft robotics. However, their crosslinked nature makes it challenging to 3D print complex geometry for soft robots. Herein, a closed-loop 4D printing strategy is reported of poly(phenylene polysulfide) networks (PSNs) and their magnetic particle composites (MPSNs) to fabricate multi-functional soft robots with programmable shape-morphing capabilities. The dynamic S─S bonds within the loosely crosslinked PSNs impart shear-thinning behavior, enabling hot-melt extrusion of both PSNs and MPSNs into complex architectures. After shape-programming, 3D-printed PSN and MPSN structures exhibit heat- or light-triggered shape recovery and allow modular assembly for spatially selective shape-morphing governed by the distinct glass transition temperatures of the PSN series. These architectures can be readily reprinted into new form factors, demonstrating a closed-loop and sustainable 4D printing. With multi-stimuli responsiveness and solvent resistance provided by the PSN composites, the MPSN capsule serves as an on-demand catalyst-releasing magnetic stirring bar in a reagent-containing solution, autonomously releasing catalysts at a preset temperature to facilitate carbamate synthesis. The 4D printable MPSNs offer a sustainable platform not only for adaptable shape-morphing and dynamic actuation but also for autonomous task execution in next-generation soft robotic applications.
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http://dx.doi.org/10.1002/adma.202507057 | DOI Listing |
Chemistry
September 2025
Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center for Soft Matter Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
Sequence-controlled polyester-based alternating copolymers have attracted significant interest due to their biocompatibility, biodegradability, closed-loop recyclability, and hydrolytic degradability, offering broad potential in biomedical and sustainable materials. Among the available strategies, regioselective ring-opening polymerization (ROP) of asymmetric cyclic di(thio)esters and cyclic(ester-amide)s has emerged as a promising approach for constructing alternating copolymers with precise sequence- and stereo-control, structural diversity, and tunable properties. This review classifies asymmetric cyclic monomers into two categories: (1) monomers with two aliphatic ester bonds, where regioselectivity is mainly dictated by steric differences and typically requires tailored metal catalysts; and (2) monomers with chemically distinct reactive sites (e.
View Article and Find Full Text PDFInt J Occup Saf Ergon
September 2025
College of Safety Science and Engineering, Civil Aviation University of China, China.
This study investigates how sustained governance of hidden hazards influences safety performance in port systems, using data from 54 production and key non-production enterprises within the Tianjin Port Group. Employing correlation analysis, regression modeling and mediation-moderation analysis, the study finds that both systematic hazard governance and standardized safety management significantly improve safety outcomes. Basic management-level governance directly reduces the frequency of incidents, while site-level governance enhances safety performance indirectly by promoting standardization.
View Article and Find Full Text PDFCureus
August 2025
Spinal Surgery, Royal National Orthopaedic Hospital, London, GBR.
Background: Venous thromboembolism (VTE) is a preventable complication following orthopaedic surgery. While most guidelines focus on arthroplasty, a significant number of knee surgeries fall under non-arthroplasty procedures, where post-operative VTE prophylaxis recommendations vary depending on anaesthetic time and weight-bearing status. National guidelines and available literature suggest the use of VTE prophylaxis for these cases, yet adherence in clinical practice remains inconsistent.
View Article and Find Full Text PDFAdv Mater
September 2025
Department of Mechanical Engineering, University of Alberta, Edmonton, AB, T6G 1H9, Canada.
Polyesters, with their tunable chemical structures and environmental sustainability, have drawn growing attention as solid polymer electrolytes for next-generation solid-state lithium metal batteries (SSLMBs). Through a comprehensive experimental and theoretical study involving the systematic variation of carbon chain lengths in the flexible (diol) and coordinating (diacid) segments, along with selective fluorination at distinct positions along the polymer backbone, 18 types of polyester are fabricated and demonstrate that fluorination at the coordinating segment significantly enhances ionic conductivity by suppressing crystallinity. In contrast, fluorination at the flexible segment reduces ionic migration barriers by providing more homogeneous coordinating sites, thereby improving the lithium-ion transference number, despite increasing chain rigidity and a reduction in overall ionic conductivity.
View Article and Find Full Text PDFJ Environ Manage
September 2025
School of Industrial Engineering, Iran University of Science and Technology, Tehran, Iran.
Agricultural supply chains face significant challenges in achieving food security and sustainability, particularly due to climate change and waste production. Effectively managing these supply chains, especially in the context of uncertainties, is crucial for optimizing resource use and minimizing waste. This research develops a multi-objective optimization for designing a sustainable and responsive closed-loop agricultural supply chain network, focusing on jujube products under uncertain conditions.
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