The widespread use and environmental persistence of polycarbonates (PCs), particularly bisphenol A-derived polycarbonate (PC-BPA), have created an urgent need for sustainable solutions. Herein, we report a DMAP-mediated, metal-free upcycling approach...

A novel red-emissive fluorescent dye for the selective detection of polyurethane in environmental matrices; river, sea, and soil.

Polycarbonate (PC)-based capsule endoscopes (CEs) face significant challenges such as high friction against gastrointestinal mucosa, susceptibility to biofouling (including protein adsorption and bacterial adhesion), and inadequate stability of surface modifications, all of which impair clinical performance and patient safety. To overcome these limitations, this study introduces a bioinspired composite coating based on polydopamine (PDA) and zwitterionic polymers. A one-step oxidative codeposition approach was utilized to graft poly(sulfobetaine methacrylate) (PSBMA), along with control polymers using sulfopropyl methacrylate (SPMA) and 2-methacryloxyethyl phosphorylcholine (MPC), onto PC substrates via a PDA interlayer, resulting in robust PC-PDA&PSB and related composite coatings. Comprehensive characterization─including XPS, SEM, and AFM─verified successful coating deposition and revealed that the incorporation of zwitterionic polymers transformed the initially coarse PDA aggregates into uniform and continuous structures. Then, the composite coatings demonstrated synergistic functional improvements: the PC-PDA&PSB coating achieved a water contact angle of 14.3 ± 3.1°, an ultralow coefficient of friction (<0.05) in different aqueous conditions, over 80% suppression of BSA/BFG adsorption, and sustained stability after 14 days in pH 1.5 PBS. Finally, in vitro cytocompatibility assessments (CCK-8 and Live/Dead staining) confirmed noncytotoxicity, with cell viability exceeding 80%, in compliance with ISO 10993-5. This strategy effectively addresses the poor adhesion often associated with zwitterionic polymer coatings alone and provides a scalable surface modification platform for enhancing the safety and functionality of CEs. It also holds considerable promise for other biomedical devices requiring slippery and antifouling properties.

Driven by strict global regulations on legacy per- and polyfluoroalkyl substances (PFAS), short-chain alternatives such as perfluorobutanesulfonate (PFBS) are increasingly used, resulting in widespread environmental detection, notably at elevated concentrations in landfill leachates, while emission sources remain uncertain. Plastics, recognized as reservoirs of numerous chemical additives with documented but rarely investigated PFAS usage, represent a potential unidentified source. Here, 105 plastic products representing 11 types of polymers were analyzed, with 20 PFAS from 6 classes identified (confidence levels of 3 or better). Polycarbonate (PC) exhibited the highest average total PFAS concentration (713 ng/g), primarily dominated by PFBS (97%), reaching up to 6130 ng/g. PFBS, commonly co-occurred with a monohydrogen-substituted PFBS (H-PFBS), particularly enriched in PC components from electronic products, indicating intentional use as flame retardants. Consistent PFBS to H-PFBS peak area ratios observed in PC samples (∼4%) and industrial PFBS products (0.07-3%), along with patent records, suggest H-PFBS as a manufacturing impurity. Simulated leaching experiments in a realistic scenario showed rapid migration of PFBS and H-PFBS into both freshwater and seawater, achieving equilibrium releases up to 39% within 14 days. Annual PFBS emissions from PC plastics to landfill leachates in China were estimated at ∼40 kg, contributing ∼10% of the total landfill-derived PFAS flux. These findings identify that PC plastics may represent a previously underrecognized contributor to PFBS contamination in landfill leachates, emphasizing the urgent need for safer plastic additives and enhanced waste management.

Ferrate as an environmentally friendly oxidant has been widely used in the environmental remediation and versatile functionalization of carbon-based materials. In this study, we investigated its ability to induce surface wettability of polymers and its emerging applications in separating mixed plastics through flotation for recycling. It was found that ferrate (VI) formed oxygen-containing groups on the surface of polycarbonates (PCs) by selectively oxidizing the sp3-hybridized carbon atoms into hydroxyl and carboxyl moieties, in addition to introducing nanoscale iron oxides. This facilitated the selective hydrophilization of PC with a water contact angle of 60.7° but did not clearly affect the surface wettability of polyvinyl chloride (PVC). This difference in surface wettability highlighted the distinct floatability properties of PC and PVC, which can be utilized to separate mixtures of these plastics with the aid of flotation. A central composite design (CCD) utilizing response surface methodology (RSM) was applied to model ferrate oxidation and to optimize flotation. Under the optimized conditions, mixtures of PC and PVC were efficiently separated with recovery and purity values of more than 99.8 ± 0.3%. Our findings provide a rational understanding of polymer wettability tailoring and expand its emerging applications in waste plastic recycling to address environmental problems.

The present work addresses the feasibility of friction stir spot welding (FSSW) of metallic aluminum alloy ( Al6061) to thermoplastic polycarbonate ( PC ) sheets using a tapered pin tool incorporating real-time process monitoring with thrust-torque signals. Sensitivity analysis identified axial tool thrust during dwelling as the most superior indicator for joint integrity (≥ 40.1%) due to its role in enhancing interfacial mixing and bonding. The tool revolving speed primarily governs the process stability (≥ 30.9%) and thus predominantly enhances the weld strength (36.5 MPa) through controlled materials stirring. In contrast, dwell time governs the joint ductility (35.5%) by promoting adequate consolidation, while plunge depth dictates the weld hardness (43%) through prolonged deformation along dissimilar interface. An integrated multi-criteria decision-making (MCDM) analysis using ARAS, TOPSIS, and GRA provided consistent optimization trends with a strong rank correlation coefficient (&gt; 0.9), confirming methodological reliability. The findings establish a quantitative framework for optimizing FSSW of dissimilar Al-PC , offering a validated approach for achieving improved mechanical behaviour through balanced process stability.

The influence of molecular chain entanglement on the mechanical performance of polycarbonate (PC) at superhigh strain rates has been investigated, which is valuable for its safety applications like window glazing. The mechanical testing results across a wide strain rate range (0.01-100s-1) show that toughness increases with strain rate, but significant deterioration of stiffness and toughness occurs at 100s-1. This phenomenon is, for the first time, observed in real time using digital image correlation (DIC), revealing severe stress concentration and strain localization at 100s-1. Nevertheless, we find this deterioration is significantly suppressed by the high entanglement density. It strengthens the strain hardening regime and dynamic mechanical analysis (DMA) is showing that both loss modulus and tanδ values increase with entanglement density in the β-relaxation region, indicating enhanced energy dissipation, which may be the underlying origin of the improved ability to resist deformation. This work is providing fundamental insights into tailoring entanglement networks to suppress energy absorption deterioration under extreme deformation conditions.

ABSTRACT Polymer dielectric capacitors are critical for advanced energy systems. However, their operation at high temperatures faces fundamental challenges: rising conduction losses and premature breakdown under extreme coupled thermal‐electric fields lead to deteriorated energy storage properties. In this study, the trade‐off between dielectric performance and high operating temperature is effectively addressed by strategically integrating metalla‐aromatic complexes (MACs) into the polycarbonate (PC) matrix. Unlike conventional π‐conjugated fillers, the osmium (Os)‐based complex MAC‐1 features a dual‐functional molecular design. Its electron‐deficient core, formed via Os‐ligand coordination, demonstrates exceptional charge‐trapping capability. The high oxidation state of Os and expanded 5 d orbitals generate a strong positive electrostatic potential, while d π ‐ p π conjugation redistributes electron density to further localize positive charge at the metal site. This quantum hybridization creates deep charge traps through intense electron delocalization. Concurrently, axially oriented triphenylphosphine (‐PPh 3 ) ligands establish steric barriers that physically suppress space charge migration. This synergy enables PC/MACs composites to achieve remarkable energy density (7.4 J cm −3 ) and discharge efficiency (93%) at 150°C, surpassing organic semiconductors (e.g., Indacenodithienothiophene‐based acceptor derivatives ITIC‐Cl: 6.0 J cm −3 ) with 85% higher synthetic yield. The demonstrated metal‐ligand coordination provides a new design method for high‐temperature dielectric composites while expanding MACs’ utility in next‐generation energy storage systems.

The energy storage density (Ue) of a capacitor is governed by its dielectric constant (εr) and breakdown strength (Eb). In this work, single-layer capacitors of the wide-bandgap-insulating polymers polystyrene (PS), polycarbonate (PC), and poly(methyl methacrylate) (PMMA) are fabricated on indium tin oxide (ITO)-coated borosilicate glass substrates with gold top-contacts. Dielectric layers approximately 2-5 μm thick are spin-coated and deposited on the ITO-coated substrates. Dilute concentrations of the small molecules dibenzotetrathiafulvalene (DBTTF), tetrakis(methylthio)tetrathiafulvalene (TMT-TTF), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), and 1,3,4,5,7,8-hexafluorotetracyanonaphthoquinodimethane (F6TCNNQ) are solution-blended into each dielectric layer, and their effects on device performance are analyzed. When added in concentrations ranging from 0.01 to 1 wt % with respect to the concentration of polymer in the spinning solution, it is found in nearly all cases that these small molecules enhance the breakdown electric field strength of the polymer capacitors and as a result improve their maximum energy density by as much as 190% relative to control devices with no additives present. A maximum breakdown electrical field strength of 850 MV/m and a corresponding energy density of 16.2 J/cm3 are observed in PMMA with 0.1 wt % F4TCNQ capacitors, the best-performing devices in this study. The efficiency of the capacitors also improves at submaximal electric fields when small molecules are included. This work demonstrates the ability to use dilute blended electroactive additives in polymer capacitors to improve key performance metrics while helping to decrease the energy losses that hinder the applicability of capacitors comprising solution-processable engineering polymers such as PC and PMMA. The choice of readily soluble polymer dielectrics and complementary use of simple solution processing offer a scalable, cost-effective method for the production of high-performance polymer capacitors.

SUMMARYSynthetic polymers have transformed modern life, giving rise to a wide spectrum of versatile materials commonly known as plastics. They are essential to industries including packaging, medical devices, automotive, textiles, and many consumer goods. However, significant environmental challenges have emerged because of the same properties that make plastics so useful. Of the estimated 400-450 million tons (Mt) of plastics produced each year, nearly 80 percent end up in the environment. Many of these plastics will persist in nature for hundreds or even thousands of years because they are mostly not biodegradable or poorly biodegradable. The identification of polymer-active microorganisms and enzymes that target most fossil fuel-based plastics is one of the greatest challenges microbiologists are facing today. Currently, more than 255 functionally verified plastic-active enzymes from more than 11 microbial phyla are known. Here, we summarize current knowledge on the microbial pathways and enzymes involved in the degradation of polyethylene terephthalate (PET), polyamide (PA) oligomers, ester-based polyurethane (PUR), and polycarbonates (PC), as well as some of the most widely used bioplastics. We also highlight the challenges microbiologists face in identifying microorganisms acting on highly persistent commodity polymers such as polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), ether-based PUR, PA, polystyrene (PS), epoxy resins, and synthetic rubber (SR), for which no truly efficient degraders are currently known. We highlight methods used to discover novel microorganisms and enzymes involved in biodegradation and measure and quantify their activities. Finally, we will review the biotechnological applications of microbial-driven plastics recycling.

Mixed polyester wastes with different chemical structures remain a key obstacle to achieving circularity in plastic utilization. Here, a programmable one-pot photothermal strategy is reported using a catalyst derived from a bimetallic MOF (Zn/Co-ZIF-C) through pyrolysis of a Zn/Co-integrated precursor. This system enables the efficient and sequential depolymerization of polycarbonate (PC), polylactic acid (PLA), and polyethylene terephthalate (PET) in mixed streams by simply tuning the irradiation intensity. Selective glycolysis of PC, PLA, and PET is triggered at ≈420, 520, and 650mW cm-2, respectively, enabling stepwise monomer recovery in a single reactor. Density functional theory calculations reveal a dual-site cooperative mechanism, in which ZnO and Co-Nx sites cooperatively activate ester bonds and ethylene glycol, offering a mechanistic basis for the observed substrate-specific reactivity. The Zn/Co-ZIF-C catalyst exhibits broadband light absorption, strong catalytic activity, and excellent recyclability, maintaining over 95% PET conversion across five cycles. Moreover, it achieves monomer yields above 80% from nine real-world post-consumer plastics, while simultaneously removing dyes and performing magnetic separation. This work presents a robust and scalable catalytic platform for light-controlled, selective upcycling of complex polyester mixtures, offering new opportunities for sustainable plastic circularity.

Transparent conductive materials (TCMs) are essential for optoelectrical devices ranging from smart windows and defogging films to soft sensors, display technologies, and flexible electronics. Materials, such as indium tin oxide (ITO) and silver nanowires (AgNWs), are commonly used and offer high optical transmittance and electrical conductivity, but suffer from brittleness, oxidation susceptibility, and require high-cost materials, greatly limiting their use. Carbon nanotube (CNT) networks provide a promising alternative, featuring mechanical compliance, chemical robustness, and scalable processing. This study reports an aqueous ink formulation composed of ultra-long mix-walled carbon nanotubes (UL-CNTs), compatible with the flow coating process, yielding uniform transparent conductive films (TCFs) on polyethylene terephthalate (PET), glass, and polycarbonate (PC). The resulting films exhibit tunable transmittance (85%–88% for single layers; ~57% for three layers at 550 nm) and sheet resistance of 7.5 kΩ/□ to 1.5 kΩ/□ accordingly. These TCFs maintain stable sheet resistance for over 5000 bending cycles and show excellent mechanical durability with negligible effects on heating performance. Post-deposition treatments, including nitric acid vapor doping or flash photonic heating (FPH), further reduce sheet resistance by up to 80% (7.5 kΩ/□ to 1.2 kΩ/□). X-ray photoelectron spectroscopy (XPS) results in reduced surface oxygen content after FPH. The photonic-treated heaters attain ~100 °C within 20 s at 100 V. This scalable, water-based process provides a pathway toward low-cost, flexible, and stretchable devices in a variety of fields, including printed electronics, optoelectronics, and thermal actuators.

Additive Manufacturing (AM) using Fused Layer Modelling (FLM) often results in polymer components with limited and highly anisotropic mechanical properties, exhibiting structural weaknesses in the layer direction (Z-direction) due to low interlaminar adhesion. The main objective of this work was to investigate and quantify these mechanical limitations and to develop strategies for their mitigation. Specifically, this study aimed to (1) characterize the anisotropic behavior of unreinforced Polycarbonate (PC) components, (2) evaluate the effect of continuous, unidirectional (UD) carbon fiber tape reinforcement on mechanical performance, and (3) validate experimental findings through Finite Element Method (FEM) simulations to support predictive modeling of reinforced FLM structures. Methods involved experimental tensile and 3-point bending tests on specimens printed in all three spatial directions (X, Y, Z), validated against FEM simulations in ANSYS Composite PrepPost (ACP) using an orthotropic material model and the Hashin failure criterion. Results showed unreinforced samples had a pronounced anisotropy, with tensile strength reduced by over 70% in the Z direction. UD tape integration nearly eliminated this orthotropic behavior and led to strength gains of over 400% in tensile and flexural strength in the Z-direction. The FEM simulations showed very good agreement regarding initial stiffness and failure load. Targeted UD tape reinforcement effectively compensates for the weaknesses of FLM structures, although the quality of the tape–matrix bond and process reproducibility remain decisive factors for the reliability of the composite system, underscoring the necessity for targeted process optimization.

The regression rate of seven three-dimensionally printable materials have been investigated and compared to a traditional fuel [hydroxyl-terminated polybutadiene (HTPB)]. The materials investigated include acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), low-density polyethylene (LDPE), polypropylene (PP), polyethylene terephthalate glycol (PETG), polyamide 66 (Nylon 66), and a UV-curable resin (CLEAR). Although all fuels can be three-dimensionally printed, the former six fuel grains were cast to avoid porosity effects introduced from additive manufacturing. The latter fuel was printed using stereolithography. All the fuels were analyzed using elemental analysis and calorimetry methods to determine their respective compositions of carbon, hydrogen, oxygen, and nitrogen along with their heats of formation. A laboratory-scale hybrid rocket motor was used to perform a series of short- (2.5–3.5 s) and long-duration (10 s) burns to measure each fuel’s regression rates using thickness-over-time and ballistic reconstruction techniques. HTPB demonstrated the highest regression rate, followed by ABS and CLEAR, while the remaining fuels showed similar, lower regression rates. The experimental data set provided in the current study also provides baseline data that can be used for predictive modeling of additively manufactured fuel systems.

The parts fabricated using the material extrusion (MEX) process exhibit anisotropic mechanical properties depending on the build orientation, primarily due to incomplete interlayer bonding. In this study, a new polycarbonate (PC) is adopted, and the anisotropic behavior of parts produced from this material is quantitatively investigated in MEX. First, we examine the deformation behavior of the material extruded (MEXed) parts according to chamber temperature. Additionally, we evaluate the surface roughness of MEXed parts as a function of the nozzle temperature. Finally, to identify the tensile strength anisotropy, tensile tests are conducted on MEXed specimens in two deposition directions using three nozzle temperatures that produced superior surface roughness. As a result, a PC adopted in this study exhibits relatively low tensile strength anisotropy, indicating that it is well suited for the MEX. Overall, this study not only provides a systematic procedure for optimizing the process parameters when adapting a new polymer to MEX, but also offers practical guidance for evaluating tensile strength anisotropy to determine whether the material is suitable for MEX.

Polymeric materials have become important components in prefilled syringes, drug delivery systems, and advanced medical devices. Background/Objectives: Nitrogen dioxide gas is used for the terminal sterilization of drug delivery systems. For the implementation of sterilization methods, compatibility with materials must be demonstrated such that the materials maintain product requirements and specifications after sterilization and at the time of use (i.e., product shelf life). Methods: Commonly used polymers were selected based on their chemical structures to provide insight into the nature of reactions that occur at the temperature and NO2 concentration levels used in the sterilization process. After exposure to the NO2 process, materials were evaluated for chemical, mechanical, and biocompatibility properties. Results: In this paper, we demonstrated the compatibility of polymers comprising carbonyl, unsaturated ester, and ketone groups which have been used in medical devices sterilized with NO2. No significant chemical or physical changes were observed upon the treatment of Amorphous Polyester, Polysulfone (PSU), Polycarbonate (PC), PolyEtherEtherKetone (PEEK), PolyArylEtherKetone (PAEK), and Polypropylene (PP) with NO2 at a sterilization temperature of 20 °C. At this relatively low sterilization temperature, the reactions of NO2 with the polymer do not typically occur because the activation energies of these reactions require much higher temperatures. Conclusions: Not all materials will be compatible with NO2 sterilization, and even with the established data, many devices will need to have their polymers evaluated for compatibility before moving to NO2 sterilization. These results will provide guidance to device designers selecting materials for new drug delivery devices and to regulators that review the safety and efficacy of these devices.

Track-etched polycarbonate (PC) membranes with nanochannels are versatile materials for electrochemical, energy-harvesting, and separation applications. Precise control over their surface charge is critical, as it governs ion selectivity, electroosmotic flow, and overall ionic transport behaviour in confined nanochannels. However, environmentally friendly and scalable strategies to precisely tune their surface charge remain limited. Amination is a practical approach for PC membrane functionalisation, as it introduces protonatable amine groups that enhance the positive surface charge and enable further chemical modifications via mild, aqueous reactions. Here, we report a simple aqueous amination method that enables systematic control of surface charge density in PC membranes between 0.0015–0.0034 C cm−2. Commercial PC membranes with nominal pore sizes of 0.015, 0.05, and 0.1 µm were functionalised with a series of amines, hexamethylenediamine (HMDA), triethylenetetramine (TETA), polyethyleneimine (PEI), and glycine (Gly), through urethane-bond formation with surface carbonyl groups under mild aqueous conditions. Elemental and spectroscopic analyses confirmed efficient functionalisation and tuneable nitrogen content (9.7–22.6 at%), related to variable surface charge density, achieved by varying reaction parameters such as concentration, time, temperature, and amine type. The highest surface charge density of 0.0034 C cm−2 was achieved using 5% w/v TETA on PC membranes with 0.1 µm diameter. This scalable, low-energy pathway for PC membrane functionalisation is even compatible with ultrasmall pores, down to ∼15 nm. The charge densities achieved through this green aqueous functionalisation are the highest among other surface charge-tuning methods, such as plasma, ultraviolet, or polymer-grafting methods. Aqueous amination-based functionalisation is suitable for fabricating charge-tuneable, ion-selective membranes for nanofluidic energy conversion, electrochemical sensing, and other surface-charge-governed applications.

Microplastics (MPs) in the urban atmosphere have been widely reported. However, the distribution of urban atmospheric microplastics (AMPs) under the influence of the East Asia monsoon remains unknown. In this study, total suspended particle (TSP) samples were collected, and polyethene terephthalate (PET) and polycarbonate (PC) MPs concentrations were quantified using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Higher concentrations of PET and PC were found in the dry season (176.3 ± 22.3 ng/m3 and 41.0 ± 12.6 ng/m3) compared to those in the wet season (49.6 ± 12.0 ng/m3 and 14.7 ± 6.5 ng/m3). Both the concentrations of PET and PC were negatively correlated (p &lt; 0.05) with the frequency of southeast winds, while being positively correlated with the frequency of northwest winds (p &lt; 0.05). Air mass trajectories of the sampling site indicate that during the wet season, a larger number of air masses originate from the oceanic direction, while more air masses come from downtown in the dry season. This further indicates the influence of atmospheric transport on the distribution of PET and PC in the air. In addition, the concentration of PET in the air was significantly correlated with the relative humidity, which may be due to the high proportion of fibrous MPs in PET.

Polymer-specific microplastic risks and microbial community shifts in a freshwater ecosystem: Field evidence from the Hunter River, Australia.

Enhancing analytical capabilities at an affordable cost: A lab-made 3D-printed external reflection accessory for versatile spectroscopic exploration.