ABSTRACT Halloysite nanotubes (HNTs) are investigated as functionally active nanofillers for tuning PEDOT:PSS thin films. HNTs from Dragon Mine (DG, USA) and Matauri Bay (NZ, New Zealand), characterized by different aspect ratios and surface chemical characteristics, are incorporated at 1.0–7.5 wt.% without secondary dopants to highlight specific HNT‐related interfacial effects. A non‐monotonic dependence of local conductance on DG content is observed, with a maximum at low loading (2.5 wt.%). This trend reflects the balance between enhanced connectivity of PEDOT‐rich domains at low concentrations and disruption of conductive pathways due to nanotube aggregation at higher loadings. It is suggested that DG acts as an active modulator, promoting polymer chain reorganization and enabling a denser hopping network, thereby enhancing local electrical response and mechanical stiffness. In contrast, NZ behaves as a passive filler, preserving the intrinsic ion‐storage capability of PEDOT:PSS without improving charge transport, highlighting the dominant role of interfacial electrostatic interactions. Electrochemical analysis shows that DG favors electronic transport at the expense of ionic accumulation, whereas NZ maintains capacitive behavior. The nanocomposites exhibit good biocompatibility, with improved SH‐SY5Y cell viability at low DG loading. These results provide design guidelines for independently tuning electrical, electrochemical, and mechanical properties in conductive polymer nanocomposites.
ABSTRACT Since 1950, global plastic production has increased at an average rate of approximately 8.5% per year, resulting in a total carbon footprint of nearly two gigatonnes of carbon dioxide‐equivalent (1.8 Gt CO2‐equivalent) in 2019, accounting for 4.5% of all worldwide greenhouse‐gas (GHG) emissions. These trends highlight the urgent need for environmentally sustainable polymer manufacturing technologies. This review examines polymer bonding methods and techniques, which play a critical role in a wide range of polymer‐based manufacturing processes. Particular emphasis is placed on a recently identified, energy‐efficient and environmentally friendly bonding phenomenon referred to as deformation‐induced bonding (DIB), and its potential scope across rapidly growing areas, including pharmaceutical, recycling, bio‐packaging, lamination and sealing, 3D printing, and advancements in traditional bonding processes. The review further provides a comparative process‐level analysis of the energy consumption and cost associated with selected conventional heat and adhesive‐based bonding methods and deformation‐induced roll bonding (DIRB), highlighting the potential energy and cost savings achievable through the adoption of DIB‐based technologies. Finally, the review outlines key future research directions for the development and implementation of DIB‐based bonding technologies.
ABSTRACT Polymer triboelectric films are key components of flexible triboelectric nanogenerators (TENGs), as their composition and interfacial characteristics govern charge generation and output performance. Poly(vinyl alcohol) (PVA) is an attractive positive triboelectric polymer due to its film‐forming ability and flexibility; however, pristine PVA films exhibit limited output. Although filler incorporation improves polymer triboelectric layers, the influence of bimetallic metal‐organic framework (MOF) composition and loading remains unclear. Here, three 2‐methylimidazole‐based bimetallic MOFs, CoZn‐MOF, CoCu‐MOF, and CoNi‐MOF, were synthesized and incorporated into PVA to construct composite triboelectric films. Their performance was evaluated using vertical contact‐separation TENGs with poly(vinylidene fluoride) as the negative layer. All MOF/PVA composites exhibited enhanced output compared with pristine PVA. The optimized CoNi‐MOF/PVA TENG with 3 wt% filler achieved the best performance, delivering an open‐circuit voltage of 194 V, a short‐circuit current of 3.0 µA, and a transferred charge density of 175 µC·m−2. It also generated 98 µW output power, charged a capacitor, powered over 100 light‐emitting diodes (LEDs), and enabled self‐powered tapping intensity and motion sensing. This work demonstrates a composition‐tuning strategy for designing MOF/PVA composite films for mechanical energy harvesting and wearable sensing.
ABSTRACT Additive manufacturing (AM) of multifunctional thermoplastic composites faces persistent trade‑offs among speed, geometric complexity, and property control. Volumetric AM (VAM) of composites, relying on beam‑based volumetric photopolymerization, is an emerging manufacturing with the potential to revolutionize all parts manufacturing; however, one of its primary hurdles is scalability to relatively large structures dimensioned at centimetres and meters. A disruptive manufacturing process is addressed here, demonstrating a magnetic field‑driven volumetric reconfiguration in heated, flat composite samples: magnetic‐field‐assisted (MFA) thermoplastic composite reshaping via utilizing untreated 10 Vol.% magnetic iron particles embedded poly‐lactic acid (PLA) composite samples (particle diameter of 10 micrometer). The study shows that MFA reshaping circumvents the AM's scalability limitations by decoupling the geometric features from the heat‐polymerization process in 10 cm‐length flat samples (0.8–2.0 mm thicknesses) and 20 cm‐length aerofoil samples, supported by magneto‑mechanical theoretical estimations, at temperatures 100% lower than process temperatures and within seconds while minimizing interlayer defects.
ABSTRACT This study demonstrates how material architecture dictates the antibacterial performance of bio‐based polylactic acid (PLA) and lignin membranes. While solution casting encapsulates active components, electrospinning (ES) yields microstructured networks (1.1 ≤ R a ≤ 4.04 µm) of fiber diameter (d) (0.2 ≤ d ≤ 6.2 µm) that maximize surface exposure of antimicrobial phenolic groups. In direct contact assays, electrospun PLA+Lignin membranes exhibit a slight selective effect, achieving a statistically significant ( p < 0.001)–13.09% growth inhibition exclusively against Micrococcus luteus (M. luteus) . Conversely, no significant antimicrobial activity is observed against Escherichia coli (E. coli) , Staphylococcus aureus (S. aureus) , or Staphylococcus epidermidis (S. epidermidis) , nor through agar diffusion assays. These findings reveal that integrating technical lignin into electrospun matrices does not provide broad‐spectrum surface protection, but offers localized, contact‐dependent activity. This structural constraint highlights the necessity of precise architectural control over leaching mechanisms when engineering active, bio‐based surfaces.
ABSTRACT The development of food packaging materials with integrated antimicrobial and antioxidant functions is a crucial strategy for advancing the sustainability of the food packaging industry. In this study, we report a novel Janus‐structured nanofibrous mat designed as a fish preservation gasket, fabricated using a modified trifluid electrospinning technique. The round side is composed of ethylcellulose and titanium dioxide, while the crescent side consists of sodium alginate, tea polyphenols, polyethylene oxide, and Triton X‐100. The outer sheath solvent facilitates a stable and continuous process for the formation of Janus nanofibers. The resulting nanofibers exhibit a uniform linear morphology and a well‐defined side‐by‐side Janus architecture. The incorporation of tea polyphenols significantly enhances the 2,2‐diphenyl‐1‐picrylhydrazyl radical scavenging activity. Furthermore, the mats demonstrate excellent antibacterial performance, achieving a 99.7% reduction against Bacillus subtilis WB800 and a 99.5% reduction against Escherichia coli DH5α within 0.5 h, which is attributed to the synergistic effect of tea polyphenols and titanium dioxide. Preservation tests demonstrate that the gaskets extended the shelf life of packaged fish to 9 days. Overall, this study establishes a new biomolecule‐based nanofibrous platform with synergistic multifunctionality, offering a promising strategy for sustainable food preservation applications.
ABSTRACT Silk fibroin (SF) exhibits excellent properties as a safe biomaterial. Although blending SF with certain polymers enhances its properties, such as its flexibility, degradability, and cell affinity, this integration also presents some challenges. This study explores changes in the structural and physical properties of SF films upon being modified with an oligopeptide composed of the hydrophilic amino acid glutamic acid (GLU). To facilitate peptide attachment, carboxyl groups on the SF film surface are increased by oxygen plasma treatment, followed by oligopeptide conjugation. Structural analysis and property evaluation show that this modification suppresses crystalline structure formation in SF and increases both its flexibility and hydrophilicity. These findings suggest that GLU modification is an effective method for controlling the structural changes and properties of SF, highlighting its potential for diverse applications.
ABSTRACT Pluronics are synthetic, amphiphilic triblock copolymers consisting of hydrophilic polyethylene oxide (PEO) segments and hydrophobic polypropylene oxide (PPO) segments arranged in a PEO–PPO–PEO configuration. Owing to their amphiphilic nature, these polymers can spontaneously organize or associate with other components to generate micellar nanocarriers, supporting diverse applications across pharmaceutical and related fields. Their favorable properties, including biocompatibility, low toxicity, biodegradability, and efficient micelle formation, make them particularly attractive for drug delivery systems. Furthermore, chemical or biological modification of Pluronics can introduce stimuli‐responsive characteristics, facilitating controlled, sustained, and site‐specific drug release. This review summarizes the structural attributes, classifications, and synthesis approaches of Pluronics, and discusses the use of Pluronic‐based micelles for drug and gene delivery across multiple administration routes, including oral, topical, ocular, brain, pulmonary, and tumor‐targeted systems, with emphasis on both in vitro and in vivo evaluations.
ABSTRACT Poly(lactic acid) (PLA) foams offer low density, high specific strength, biocompatibility, and biodegradability, and are therefore regarded as promising sustainable alternatives to conventional petroleum‐based foams. Their broader application, however, is constrained by the inherently low melt strength, slow crystallization kinetics, and narrow processing window of PLA, which make it difficult to achieve high expansion ratios together with uniform and stable cellular structures. This review summarizes the principles, equipment, and application ranges of extrusion foaming, autoclave foaming, injection foaming, and foaming integrated with 3D printing. Physical, chemical, and combined foaming mechanisms are discussed, with particular emphasis on how material characteristics and processing conditions govern cell nucleation, growth, and stabilization. Recent developments in foaming technologies and processing equipment are reviewed, together with the remaining challenges in cellular uniformity, process reliability, manufacturing cost, and scale‐up. Emerging research directions include intelligent process control, sustainable blowing agents, precise tailoring of cellular architectures, and multifunctional PLA foams. These advances are expected to support the performance enhancement and industrial adoption of PLA foam products.
ABSTRACT This study aimed to develop and characterize Cellulose Nanofiber/Polycaprolactone (CNF/PCL) composites using a low‐temperature, organic‐solvent‐free aqueous processing method. The composites were prepared by gradually incorporating a hydrated CNF/PEG gel into PCL melted at 75°C through repeated rolling and folding. FTIR and DSC results were consistent with physical blending, without evidence of new chemical bonding or additional thermal transitions. CNF incorporation significantly improved tensile performance: all composite formulations exhibited tensile strengths above 30 MPa. The highest value, approximately 35 MPa, was obtained for the sample containing 0.5 wt% CNF, compared with about 19 MPa for neat PCL. The composites also exhibited Young's moduli of approximately 500–600 MPa. Porosity increased from approximately 20% for neat PCL to more than 42% for the composite containing 99.01 wt% PCL and 0.99 wt% CNF. SEM showed distributed fibrillar features without prominent CNF‐rich agglomerates. Surface roughness remained within a similar submicrometer range, while skewness and kurtosis were more sensitive to localized surface variation caused by changes in composite formulation. These findings demonstrate that aqueous rolling and folding can produce mechanically reinforced CNF/PCL composites with improved tensile properties for potential biomedical applications.
ABSTRACT Microfluidic‐derived microbubble‐templated scaffolds (Mt‐Ss) enable controllable and homogeneous pore architectures in tissue constructs, offering advantages over conventional fabrication methods. In this study, we developed antibacterial alginate‐polyethyleneimine (Alg‐PEI) scaffolds incorporating silver nanoparticles (AgNPs) using a T‐junction microfluidic system to construct well‐ordered Mt‐Ss for potential wound‐healing applications. AgNPs were synthesized with an average diameter of 25.63 ± 3.7 nm, a polydispersity index (PDI) of 0.11, and a zeta potential of −21.7 ± 9.1 mV, indicating near indicating narrow size distribution approaching monodispersity and electrosterically stabilized nanoparticle formation. The resulting Mt‐Ss exhibited tunable pore sizes ranging from 90 to 175 µm, depending on PEI and AgNP concentrations, and exceptional water retention capacities of 3685–4300%, which are favorable for managing exudative wounds. ICP‐MS analysis revealed a sustained total silver release profile up to 168 h, with the Alg‐PEI(0.1)/AgNP0.1 formulation demonstrating the highest cumulative release of 8.7 ppm. Notably, Mt‐Ss containing 1% PEI and 0.05% AgNPs exhibited cytocompatibility and antibacterial activity against Gram‐negative Escherichia coli ( E. coli ‐ATCC 25922), Gram‐positive Staphylococcus aureus ( S. aureus ‐ATCC 29213), and clinically relevant Methicillin‐resistant S. aureus ( MRSA , ATCC 43300). Overall, Alg‐PEI/AgNP Mt‐Ss demonstrate sustained antibacterial efficacy, superior fluid absorption, and favorable in vitro cytocompatibility, representing a potential candidate for the future management of infected wound environments.
ABSTRACT We investigated the properties of waste polyethylene and ground tire rubber (GTR) blends as a function of different mixing strategies and GTR surface modifications. The GTR surface was modified by ionizing radiation in air and by radiation induced grafting (maleic anhydride, MAH and methyl methacrylate, MMA). We confirmed the presence of oxygen‐containing functional groups by Fourier‐transform infrared spectroscopy (FTIR), and the formation of specific morphological structures by scanning electron microscopy (SEM). We prepared mixtures containing polyethylene and GTR using three different mixing methods. To improve mechanical compatibility, we used ethylene‐vinyl acetate copolymer (EVA), which improved the tensile strength by 25% and the elongation at break by 84%. The tensile strength of the sample containing GTR grafted with MAH increased by 30% relative to the reference sample (MMA 26%), while its elongation at break exceeded it by 158% (MMA 128%). Dynamic mechanical measurements revealed that although the addition of EVA reduced the damping coefficient, radiation treatment and grafting increased it. The SEM analysis indicated that strong adhesion and chemical compatibility had developed between the modified GTR and the matrix. The combined use of radiation‐induced grafting and blending sequence is an effective method for optimizing the properties of waste‐based polymer blends.
ABSTRACT Large bone defects caused by trauma, disease, or aging often exceed the natural regenerative capacity of bone, requiring clinical interventions such as grafts or prosthetic replacements. In native bone, hydroxyapatite nanocrystals are hierarchically embedded within type‐I collagen fibers, providing both mechanical strength and biological functionality. In this study, a collagen‐based composite scaffold containing boron/strontium co‐substituted hydroxyapatite (Col‐BSH) was developed to enhance the bioactivity of collagen through the incorporation of bioactive ions. Composite scaffolds with varying ceramic phase contents (low, medium, high) were characterized in terms of their physicochemical, thermal, and mechanical properties, along with 28‐day boron and strontium release behavior. Thermal analyses revealed improved stability in both Col‐H and Col‐BSH composite series. Mechanical tests demonstrated the Col‐BSH‐M composite with ∼25 wt.% ceramic phase exhibited optimal performance, with a maximum strength of 113.74 ± 5.73 kPa and toughness of 1149.97 ± 38.24 kJ/m3. In vitro release studies indicated boron and strontium release were between 14–18 mg/L and 6–21 mg/L, respectively, for Col‐BSH‐M over 28 days. The composites exhibited good hemocompatibility and cytocompatibility. Furthermore, a preliminary in vivo study conducted at an ectopic site demonstrated the angiogenic and osteogenic properties of Col‐BSH‐M. Consequently, the Col‐BSH‐M scaffold has shown promising potential for bone tissue engineering applications.
ABSTRACT Bifunctional electrochromic supercapacitor devices (ESD), which integrate electrochromic and pseudocapacitive functionalities within a single electrode material, have emerged as a promising platform for intelligent energy management systems. However, the rational molecular design principles governing the simultaneous optimization of both functions remain insufficiently understood. Herein, we report a systematic chalcogen engineering strategy in which triphenylamine (TPA) is coupled with furan (M1), selenophene (M2), and thiophene (M3) to yield three structurally analogous monomers electropolymerized on indium tin oxide (ITO) electrodes to afford the corresponding polymer films P1, P2, and P3. By isolating the chalcogen heteroatom as the sole structural variable within an otherwise identical molecular framework, we establish comprehensive chalcogen‐dependent structure‐property relationships governing optical bandgap, charge transfer resistance, pseudocapacitive storage mechanism, electrochromic optical contrast, and polaron band position simultaneously. The thiophene‐bridged polymer P3 delivers the most favorable bifunctional performance, achieving a maximum areal specific capacitance of 10.63 mF/cm2, energy density of 1.71 µWh/cm2, and optical contrast of 66% (1100 nm), outperforming its furan and selenophene analogues. Asymmetric ESDs (AESDs) fabricated with PEDOT as the counter electrode further validates the practical device applicability of the optimized material. These results provide clear and transferable molecular design guidelines for next‐generation bifunctional electrochromic supercapacitor materials.
ABSTRACT In this work, the incorporation of hexagonal boron nitride (h‐BN) into a polyamide 11 (PA11) matrix was investigated. Composites were prepared by extrusion compounding followed by injection molding, using h‐BN contents up to 30 wt.%. To address effects of surface modification, the h‐BN surface was modified via thermal hydroxylation at 1000°C followed by grafting with (3‐aminopropyl)triethoxysilane (APTES). The materials were characterized using thermogravimetry, calorimetry, electron microscopy, dynamic and tensile mechanical methods, as well as thermal and electron conductivity methods. An adhesion factor analysis revealed inherently poor filler‐matrix bonding of h‐BN without surface treatment, which promoted a rigid‐filler toughening mechanism that enhanced stiffness and flexural properties, particularly at 10 wt.%. At higher filler loadings, thermal conductivity increased by 50% and resistivity increased by up to one order of magnitude. The results also indicated that the composites with APTES‐treated h‐BN exhibited superior particle/polymer interfacial adhesion. Improvement in flexural and tensile strengths was achieved, surpassing neat PA11. However, APTES modification did not improve thermal or electrical properties, likely because the treatment exfoliated the h‐BN particles. These findings underscore APTES treatment's role in optimizing PA11/h‐BN biocomposites for high‐performance applications while highlighting the need for refined protocols to mitigate h‐BN exfoliation‐related drawbacks.
ABSTRACT The transition toward safer and fully bio‐based wood adhesives requires both scalable processing methods and reactive formulations capable of competing with petrochemical systems. This work presents a simple and scalable route for producing waterborne colloidal suspensions of softwood kraft lignin (SKL) and lignosulfonate (LS) at solid contents reaching 55wt%, enabled by the dispersing action of LS under high‐shear homogenization without pH adjustment or organic solvents. The resulting lignin particle suspensions exhibit tunable particle size, zeta potential, and viscosity through modulation of the LS/SKL mass ratio. The lignin dispersions effectively stabilize oil‐in‐water emulsions as demonstrated with jojoba oil. Building on these properties, a fully biobased two‐component adhesive system was developed by combining the SL/SKL particle suspensions with glycerol diglycidyl ether. Lignosulfonate plays a critical role as an unconventional latent curing agent, extending pot life and enabling controlled reactivity. The adhesives display optimal lap‐shear strength with major wood failure above 4.5 MPa and maintain high mechanical performance after water immersion. Along with competitive adhesion performance, lignin‐glued plywood exhibited low VOC emissions, ranking them as recommended building materials according to a Swedish building materials assessment system. This study provides a scalable platform for valorizing technical lignins in formaldehyde‐free adhesives for engineered wood applications.
ABSTRACT This study investigates the synergistic condensed‐phase flame‐retardant mechanism of recycled polyethylene terephthalate (rPET) modified with zinc phosphinate (ZnPi) and zirconium hydrogen phosphate (ZrP). Three formulations were prepared: rPET with 4.5wt% ZnPi (ZnPi45), 4.5 wt% ZrP (ZrP45), and a hybrid containing 2.25wt%ZnPi+2.25wt%ZrP (BL225). Rheological analysis confirmed that no premature crosslinking occurs at processing temperature (265°C), indicating that char formation originates from thermally activated degradation chemistry. Thermogravimetric analysis (TGA) under air revealed that ZnPi promotes phosphorus‐assisted charring during the primary degradation window (370–470°C), while ZrP enhances residue persistence above 600°C. The hybrid BL225 exhibited an extended degradation width (ΔT10–90 = 182.07°C) and positive synergy indices of approximately 20% at 500°C and 800°C, confirming cooperative interactions. Raman spectroscopy, analyzed using three independent crystallite size calculation methods (Tuinstra–Koenig, Cancado, and Ferrari–Robertson), consistently ranked the structural order as ZnPi45>BL225>ZrP45>rPET. ZnPi45 achieved the largest crystallite size (La = 59.9 nm by Cancado method), while BL225 retained over 85% of this efficiency at half ZnPi loading. These results quantitatively support a cooperative condensed‐phase mechanism in which ZnPi generates phosphorus‐rich crosslinked networks and ZrP provides a thermally stable inorganic scaffold, collectively forming a dense, oxidation‐resistant protective char.
ABSTRACT Poly(lactic acid) (PLA) is the most widely used bio‐based and biodegradable polymer because of its versatility and relatively low cost, and PLA foams are increasingly used as alternatives to conventional expanded polymers. However, PLA shows limited biodegradability outside industrial composting, especially when dispersed in the environment. Blending PLA with polyhydroxyalkanoates (PHAs) is a promising strategy to improve its degradation behavior. In this work, fully amorphous blends of amorphous PLA and amorphous poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) (aPHA) were studied, with aPHA as the minor component at 10–30 wt.%. The blends were compounded at 185°C. TEM analysis revealed an immiscible morphology with dispersed spherical aPHA domains of 400–600 nm. All blends were successfully foamed by batch pressure‐drop foaming using supercritical CO2. Foam density and morphology depended strongly on foaming pressure and temperature. The lowest density, below 50 g/L, was achieved at 50°C and 90 bar, producing a closed‐cell structure with cell sizes of 40–80 µm. Biodegradability under simulated home‐composting conditions at 30°C was assessed by respirometry, NMR, SEC, and SEM, showing enhanced PLA degradation and total mass loss up to 84% after 4 months. In marine conditions, degradation was limited and mainly selective for aPHA.
ABSTRACT Partially bio‐based epoxy thermosets were developed using diglycidyl ether of bisphenol A (DGEBA) and two biobased amines hardeners. A novel tetra‐functional amine was synthesized from eugenol via oxidative coupling to form di‐eugenol, followed by thiol‐ene functionalization. Five formulations were prepared by varying the molar ratio of the two biobased amine hardeners to tailor the network architecture. Thermomechanical properties were evaluated by differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Furthermore, Solid‐State 1H NMR provided a multiscale experimental approach into the relationship between cross‐link density, molecular chain dynamics, and macroscopic thermomechanical properties, leading to a straightforward structure‐property correlation.
ABSTRACT Innovation in environmental monitoring is at an all‐time high due to the increased need to protect public health, preserve fragile ecosystems, enforce regulatory compliance, and mitigate environmental risks. The development of gas sensors, particularly chemiresistive gas sensors, which detect gases based on changes in electrical resistance has particularly gained attention due to their exceptional sensitivity and compact size. The performance of these sensors is greatly influenced by the fundamental properties of materials chosen to act as the sensing layer. The integration of inorganic materials with conducting polymers has become more popular in improving the sensitivity, selectivity, stability, and response kinetics of these sensors. Moreover, these composites address the impact of high operating temperature and humidity. This review focuses on the recent developments in the creation of conducting polymer composites for gas‐sensing applications, particularly composites comprising conducting polymers and metal oxides. These composite materials ensure the accurate detection of reducing or oxidizing gases in a variety of environments and can potentially be used in monitoring hazardous gaseous substances in the environment.
