Poly(trimethylene terephthalate) (PTT) is a widely used engineering polyester, but its petroleum-derived monomers conflict with current efforts to reduce reliance on fossil feedstocks. Poly(trimethylene 2,5-furandicarboxylate) (PTF), a fully bio-based analogue with properties comparable to PTT, is a promising alternative, yet the impact of chemical modifications such as copolymerization remains poorly explored. This work combines mathematical modeling with experimental characterization to predict and validate key thermal and structural properties of bio-based polyesters and copolyesters. This study underlined the successful synthesis of two series of bio-based copolymers, i.e. poly(trimethylene terephthalate-co-trimethylene glutarate) PTT-co-PTG and poly(trimethylene 2,5-furandicarboxylate-co-trimethylene glutarate) (PTF-co-PTG) via melt polycondensation. The chemical structure and composition of the copolymers were confirmed with the use of H-1 NMR spectroscopy. Limiting viscosity numbers (LVNs) ranging from 0.643 to 0.759 dL/g were obtained, indicating that the desired values were achieved. The influence of the incorporation of PTG units on thermal properties and morphology was investigated using differential scanning calorimetry (DSC). There were no significant differences in thermal stability and activation energy between the homopolymer and the corresponding copolymers.
The methacrylation of Beech organosolv Lignin with methacrylic anhydride (MA) at 65 degrees C under [4- (dimethylamino) pyridine] (DMAP) base catalysis is monitored by the FTIR OH-stretch at 3340cm(-1) and the C & boxH;C vibrations associated with the methacrylate group at 780, 810, 945, and 1637 cm(-1). Methacrylation extent increases with the MA: lignin OH molar ratio, the DMAP: MA wt%, and their interactions. Monitoring these vibrations over 48 h suggests side reactions, liberating new OH functionalities and, in turn, new grafting sites. Under these conditions, zero- and second-order kinetics fit the kinetics of lignin methacrylation equally well. Lignin methacrylate derivatives cure readily under UV light, and both the cure rate and full cure extent increase with increasing methacrylate conversion of lignin OH. The Sestak-Berggren autocatalytic kinetic model successfully describes UV-photocure, whereby the product autocatalytic (m) and reactant's exhaustion retardation (n) effects decrease with increasing methacrylation extent, from ca. 0.34 to 0.28 and from ca. 1.05 to 0.67, respectively. Lignin methacrylation can thus be tuned to adjust rheological and photocuring properties of methacrylate lignins for UV light induced processing, such as 3D printing.
This study presents an amphiphilic shape-memory hydrogel (SMH) based on poly(acrylic acid-co-n-hexadecyl acrylate) [P(AAc-co-C16A)] that integrates pH and temperature responsiveness within a single molecular network. The hydrophobic C16 side chains form reversible crystalline domains that act as physical cross-links, imparting thermal shape-memory and mechanical strength, while ionizable acrylic acid units provide pH-dependent swelling and charge regulation. An optimal composition containing 30 mol % C16A exhibited a balanced combination of mechanical robustness (E approximate to 15 MPa), a high shape-recovery ratio (>93 %), and a thermoresponsive transition near physiological temperature (37 degrees C-39 degrees C). Ibuprofen-loaded SMHs demonstrated strongly pH-dependent and thermally accelerated drug release, with enhanced release under mildly acidic conditions and further acceleration upon shape recovery. Cytocompatibility assays confirmed the hydrogels' safety for normal fibroblasts, while selective cytotoxicity toward MDA-MB-231 breast cancer cells underscored their therapeutic potential. Overall, P(AAc-co-C16A) SMHs provide a molecularly tunable platform that couples shape-memory functionality with controlled, dual-stimulus drug delivery. Their combination of reversibility, biocompatibility, and mechanical resilience offers new opportunities for localized and on-demand release systems in cancer therapy and next-generation 4D-printed biomedical devices.
Mallotumide A (MA) is a novel cycloheptapeptide isolated from the roots of Mallotus spodocarpus Airy Shaw. It exerts anticancer activity by downregulating several lipogenic enzymes and cellular respiration, particularly in triple-negative breast cancer. However, MA has poor water solubility and is highly toxic to both cancer and normal cells, limiting its therapeutic applications. To address these drawbacks, MA was encapsulated within poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) and coated with riboflavin (Rf)-modified chitosan (CR), creating (MA)PLGA/CR NPs. This study characterized the NPs and investigated their encapsulation efficiency of MA, cellular uptake, and anticancer activity in two breast cancer (MDA-MB-231 and MCF-7) and normal (MCF-10A) cell lines. The NPs were spherical with an average size of 300 +/- 6.64 nm and a zeta potential of +11.96 mV. The PLGA/CR NPs exhibited enhanced cellular uptake in both cancer cells in a dose- and time-dependent manner, while reducing toxicity in normal cells. Furthermore, the (MA)PLGA/CR NPs inhibited the viability, migration, and invasion of MDA-MB-231 cells, thereby demonstrating their potential as a targeted anticancer delivery system.
To address the global crisis of 6.3 billion tons of non-degradable plastic waste, polysaccharides (starch, chitosan, cellulose, etc.) have emerged as sustainable alternatives for food packaging. This review systematically analyzes five representative polysaccharides, highlighting their structural engineering strategies (e.g., nanocellulose reinforcement) and functional modifications (e.g., anthocyanin-based pH responsiveness). We propose a comprehensive framework integrating cost, performance, and policy factors to benchmark industrialization challenges of key polysaccharides, with starch-nanocellulose composites identified as the most scalable candidate. Integrated intelligent-active packaging systems (e.g., pH-sensitive films with real-time monitoring) demonstrate synergistic potential to extend food shelf life by 30%–50% while aligning with global policies (EU SUP Directive, China's 14th Five-Year Plan). Despite challenges in thermal stability (e.g., starch degrades at 100°C–180°C) and scalability, policy-technology synergies are critical to accelerate commercialization.
Poly(2-oxazoline)-imidazole (POZ-Im) polymers were synthesized by one-pot termination of 2-ethyl, 2-propyl-, and 2-phenyl-2-oxazoline homopolymers with imidazole and evaluated as thermal latent curing agents (TLCs) for one-component epoxy resins (OCERs). H-1 NMR, FTIR, and MALDI-TOF confirmed successful synthesis of polymers. The polymers were amorphous, exhibiting glass transition temperatures of 43 degrees C (PEOZ-Im), 24 degrees C (PPrOZ-Im), and 91 degrees C (PPhOZ-Im) and showed thermal stability with onset degradation at 364 degrees C-375 degrees C. When incorporated into DGEBA at a fixed 5 phr Im-to-epoxy ratio, their miscibility and curing performance varied with side-chain chemistry. PPhOZ-Im was fully miscible, PPrOZ-Im was partially miscible, and PEOZ-Im formed fine dispersed domains. Dynamic DSC revealed left-limit temperatures of 91.75 degrees C (PEOZ-Im), 94.22 degrees C (PPhOZ-Im), and 103.28 degrees C (PPrOZ-Im). Rheological analysis showed that PPrOZ-Im/DGEBA exhibited the longest gelation time, followed by PEOZ-Im/DGEBA and PPhOZ-Im/DGEBA. Shelf-life estimations based on viscosity doubling times and Arrhenius extrapolation indicated stability of 88 days (PPrOZ-Im/DGEBA), 34 days (PEOZ-Im/DGEBA), and 32 days (PPhOZ-Im/DGEBA) at -20 degrees C. These results demonstrate that POZ-Im polymers provide tunable latency and curing behavior suitable for advanced composite applications.
The utilization of hemicellulose in fiber production offers a sustainable route for textiles by transforming an otherwise wasted component of wood biomass into value-added material. The high hemicellulose content in these fibers poses challenges for alkaline wet processing, particularly during dyeing with reactive dyes. This study provides a systematic evaluation of how different alkaline conditions influence both the structural stability and dyeability of hemicellulose-rich (HR-Cell) fibers, addressing a knowledge gap in the processing of next-generation biobased cellulosic fibers. We investigate the dyeability and structural stability of HR-Cell fibers under sodium hydroxide (NaOH, 5-10 g/L) and sodium carbonate (Na2CO3, 5-20 g/L) treatments. Comprehensive characterization of HR-Cell fibers, including carbohydrate analysis, molar mass distribution, intrinsic viscosity, degree of polymerization, and crystallinity, showed that NaOH at 10 g/L led to hemicellulose degradation and cellulose depolymerization, whereas Na2CO3 preserved hemicellulose even at elevated concentrations. Dyeing experiments using C.I. Reactive Red 141 and C.I. Reactive Yellow 6 revealed that HR-Cell fibers consistently exhibited higher dye exhaustion, fixation, and color strength compared to cotton, viscose, and Lyocell fibers. The most favorable dyeing results were achieved with 15 g/L Na2CO3, which offered optimal conditions for activating fiber hydroxy groups, minimizing dye hydrolysis, and preserving hemicellulose in the fibers. Colorfastness tests confirmed very good to excellent resistance to washing, rubbing, and light across all samples and conditions.
Soft polyurethane fouling-release coatings are modified with synthesized mPEG-305, a hydrophilic PEG-based additive, and a commercially hydrophobic PDMS-based additive by click chemistry to generate hydrophilic and hydrophobic surface domains. Sessile drop contact angle measurements reveal polarity gradients ranging from triangle theta = -32 degrees to triangle theta = 120 degrees. AFM and SEM demonstrate successful additive incorporation (hydrophilic and hydrophobic additive addition of 2.5-20 mol% and 5-15 mol%) and the formation of two-phase systems with microstructures, including spherical hydrophobic and characteristic "wrinkled" morphologies. Captive bubble contact angle measurements of systems with "wrinkled" microstructures indicate dynamically hydrophilic behavior, with contact angle changes of up to 15 degrees over 33 days of immersion in demineralized water. Static immersion tests in the North Sea (Helgoland) for 18 weeks demonstrate enhanced bio-repulsivity, with LoF values decreasing from 4 to 2-3 for systems with the strongest polarity gradient (triangle theta = 112 degrees-120 degrees), additive contents of 5-10 mol%, dominant wrinkled microstructures with pronounced stiffness (5 mPa) and topographical (100 nm) gradients, and dynamically hydrophilic contact angles changes of 15 degrees. This highlights the critical influence of polarity gradients, microstructural heterogeneity and dynamic hydrophile behavior on the bio-repulsivity of polyurethane coatings.
An one-step procedure of simultaneous electrospraying and electrospinning is employed to produce fiber mats of a poly(vinylidene fluoride) (PVDF)/thermoplastic polyurethane (TPU) blend and polylactide (PLA) coated with singlewalled carbon nanotubes (SWCNTs). Thermoelectric investigation of the mats yielded Seebeck coefficients of 21-27 mu VK-1 that are almost independent of the SWCNT content and the polymer type. Control measurements using SWCNT buckypapers reveals that the thermoelectric properties of the SWCNTs is mostly determined by n-type doping effect of the solvents and additives used for electrospraying; the polymer nanofibers act mostly as porous mechanical support. Gas sensing experiments using PVDF/TPU and PLA-based electrospun mats containing 0.25 wt% SWCNTs exposed to saturated acetone vapor demonstrate a significant sensor response (change in resistance) for both polymers. Sensor recovery is more effective in the PLA-based mats compared to the PVDF-based one. In cyclic tests with short exposure times, both mats show highly stable and reproducible sensing behavior. The sensing mechanism is primarily driven by interactions between the solvent molecules and the SWCNTs (charge transfer) rather than by interactions with the polymer matrix (e.g., polymer swelling).
With the growing demand for advanced biophysical signal monitoring systems, the development of stretchable, adaptable, and functional flexible materials has become essential. Flexible sensors capable of detecting facial expressions, voice signals, and environmental stimuli show great potential in personalized healthcare, human-machine interfaces, and wearable electronics. Despite advancements, current flexible sensors face limitations such as low sensitivity to micro-strains, insufficient anisotropy, and poor environmental adaptability, restricting their broader application. This study introduces a high-performance stretchable sensor composed of carbon nanotube (CNT) and silver (Ag)-based conductive inks integrated with a monodomain liquid crystal elastomer (LCE) substrate (Ag/CNT/LCE). The LCE substrate offers sensitive mir-costrains detection intrinsic anisotropy, and thermal-response capability. The conductive ink combines the mechanical robustness of CNTs with the excellent conductivity of Ag, suppressing CNT aggregation and improving electrical stability under strain. The Ag/CNT/LCE sensor exhibits a gauge factor of 3.93, rapid response times (120 ms), and exceptional cyclic durability over 2500 cycles. Additionally, its thermoresponsive behavior enhances adaptability to environmental changes. Demonstrated applications include facial emotion recognition, voice monitoring, and deformation-based environmental sensing. By integrating multifunctionality, structural durability, and dynamic adaptability, the Ag/CNT/LCE sensor serves as a promising platform for wearable electronics, and next-generation healthcare technologies.
Efficient recycling of mixed plastic waste remains challenging due to the intrinsic immiscibility of constituent polymers, which compromises mechanical performance. Here, a synergistic compatibilization strategy combining reactive maleic anhydride-grafted low-density polyethylene (LDPE-g-MA) and non-reactive styrene-ethylene-butadiene-styrene (SEBS) is demonstrated to enhance interfacial adhesion and mechanical properties of LDPE/PS/PA6 blends. The cooperative action of LDPE-g-MA and SEBS minimized mutual interference and improved compatibilization efficiency at both LDPE/PA6 and LDPE/PS interfaces. In the LDPE/PS/PA6 (40/30/30) blend, the bicontinuous LDPE/PS morphology with PA6 encapsulated in PS transformed into an LDPE matrix containing salami-like core-shell domains with mixed PS/PA6 cores upon addition of 5 wt.% LDPE-g-MA and 5 wt.% SEBS. In the LDPE/PS/PA6 (70/15/15) blend, the PA6@PS domains evolved into distinct, refined salami-like structures with inner PS cores and interfacial localized PA6 domains upon addition of 3 wt.% LDPE-g-MA and 3 wt.% SEBS, increasing notched impact strength from 3.3 to 18.2 kJm(-2). In the LDPE/PS/PA6 (15/15/70) blend, LDPE@PS core-shell domains converted to salami-like PS@LDPE structures with 3 wt.% LDPE-g-MA and 4.5 wt.% SEBS, enhancing impact strength from 2.9 to 11.7 kJm(-2). This work offers an effective, industrially relevant route to tailor morphology and upgrade the performance of heterogeneous plastic waste toward sustainable recycling.
Hydrogen bonding plays a pivotal yet often overlooked role in shaping the structure and dynamics of alginate-based materials. In this study, we use molecular dynamics (MD) simulations to investigate how hydration and solvent environment influence the organization of neutral alginate at the molecular and mesoscale levels. Starting from short isolated chains and progressing toward periodic and entangled systems, we systematically vary water content and examine structural responses using radial and minimal distance distribution functions, as well as geometric analysis based on Alpha Shapes. We find that hydration transforms the polymer matrix from compact, rigid bundles into layered and porous nanostructures, with water acting not merely as a plasticizer but as an active mediator of hydrogen bonding. Even small amounts of water accelerate supramolecular aggregation and promote internal flexibility. At higher hydration, polymer-polymer contacts become more diffuse yet remain structurally coherent. A comparison with ethanol reveals solvent-specific effects on porosity and tortuosity, while the functional surface composition remains robust across all conditions, closely reflecting the molecular stoichiometry of the polymer. These results provide a detailed molecular-level understanding of solvent-mediated self-assembly in alginate and offer general design principles for soft, bioinspired materials where hydrogen bonding is the key structural motif.
Perfluorinated ionomers are specialty polymers with invaluable thermal and proton transport properties that make them greatly appreciated on the market, mainly for the realization of membranes for fuel cells and water electrolyzers. Among the different materials, the short side-chain perfluorosulfonic acid (PFSA) Aquivion was demonstrated to efficiently work in a broader temperature range compared to its longer side-chain counterparts, enabling high performance and mechanical strength at high temperatures. This appealing property stimulated extensive research on its synthesis from gaseous tetrafluoroethylene and a liquid perfluoro-sulfonyl fluoride vinyl ether, and its applications. Since a recent and comprehensive report on the latest advances in this direction is missing, this review aims to discuss the recent studies in order to elucidate the polymerization mechanism and innovations in reactor technology for Aquivion. Then, the state-of-the-art of its applications, spanning from proton and anion exchange membrane fuel cells (PEMFC and AEMFC) and water electrolyzers (PEMWE) to membranes for gas separation to superacid heterogeneous catalysis, is presented, to highlight the possibilities enabled by this material while taking into account also the major limitations.
ABSTRACT Metal complexes are utilized in numerous medical and biological applications. However, their direct use as small‐molecule agents is often challenging due to rapid systemic clearance, unfavorable biodistribution, and loss of catalytic efficacy under the diluted conditions of a biological milieu. Incorporating the metal complexes into a polymer addresses these issues, providing three key advantages. First, it significantly improves pharmacokinetics by leveraging the size, which leads to a prolonged circulation and an enhanced therapeutic index for systemically administered medicines. Second, the polymer matrix creates a locally concentrated environment for the metal complexes. Neighboring metal complexes allow for efficient reactions, such as the generation of reactive oxygen species, even under biologically dilute conditions. Third, the multivalent effect of multiple binding sites on the polymer chain dramatically increases molecular recognition and binding affinity. This can be the driving force for supramolecular formation, including nanoparticles and hydrogels. Combining these merits could advance a new generation of biomaterials, enabling various types of theranostics. The polymer matrix also promotes catalytic reactions of metal complexes that cannot feasibly proceed in an ordinary aqueous solution state, mirroring a biological system. Thus, we believe that polymer‐metal complexes will further promote biomaterial development, including in medicines and artificial tissues.
The effect of deformation on the oriented crystal structure of polypropylene, specializing in capacitor film during stretching at high temperature, was verified. Two kinds of polypropylene with different isotacticity were stretched to different deformation ratios at the same temperature, and the microstructures of the oriented crystals were analyzed by synchrotron 2d wide-angle/small-angle X-ray scattering technique. Results showed that during partial melting stretching, the thickness of lamellar stacks remained constant at a fixed temperature, and the thicknesses of the lamellae crystals, and the amorphous region were invariable over a wide range of stretching deformation. However, the increased deformation led to a decrease in the lateral dimensions of the lamellar stack, indicating that the oriented crystals slipped and broke up along the stretch direction, resulting in the formation of microfibrillar structures. This increase was accompanied by an increase in crystal orientation induced by external forces. Additionally, higher isotacticity facilitated the acquisition of a high degree of orientation and crystallinity, but it had less effect on the lamellar stack thickness. This paper elucidated the relationship between the oriented crystal structure and the deformation behavior of polypropylene, thereby providing a fundamental theoretical basis for optimizing the properties of films based on the hot-stretching process.
The present work explores the use of acrylonitrile butadiene styrene (ABS) + thermoplastic elastomer (TPE) core-shell composite filaments to enable additive manufacturing of soft structures with tunable mechanical response. It investigates the effect of core/shell ratio of the filament, and raster orientation via printing, to control the mechanical anisotropy of 3D-printed structures. Load frame experiments demonstrate control over a wide range of tensile modulus (50-2200 MPa) and flexural modulus (50-2600 MPa), by varying the number and sequence of 0 degrees, +/- 45 degrees, and 90 degrees raster orientations (plies) within 16-layer test coupons. Asymmetric (with respect to the sample mid-plane) ply stacks are shown to exhibit a bending response that is sensitive to bending direction. Segmented designs, in which print orientation is varied along the length of a test coupon, are fabricated and exhibit localized bending. Analytical composite laminate theory and finite element simulations are shown to capture the broad trends in mechanical response for these 3D printed soft composites, although these models overpredict structural stiffness as ABS volume fraction increases due to strain localization and softening in the TPE phase.
Aramid fibers such as Kevlar are frequently used in protective applications due to their mechanical strength and thermal stability. However, the low surface reactivity of aramid has limited its functional modifications, particularly for enhancing water resistance, an increasingly important requirement in protective textiles. This study presents a surface functionalization approach that imparts durable hydrophobicity to Kevlar fabric. Polyacrylic acid (PAA) was used as a coupling agent to improve the adhesion of nanodiamonds (ND), including detonation (DND) and hydroxylated forms (ND-OH), to the fiber surface. Subsequent treatment with n-dodecyl tri-methoxy silane generated a robust hydrophobic finish. The PAA-DND-silane system exhibited the highest water contact angle and retained its performance after repeated washing and abrasion cycles. The enhancement in hydrophobicity was attributed to nanostructured roughness promoting a Cassie-Baxter wetting regime. Crucially, the modification did not compromise the fabric's flexibility, although it reduced the air permeability 50%. This scalable strategy offers a pathway to multifunctional aramid textiles that meet the stringent demands of modern protective gear.
The potential of aminoterminated hyperbranched polyglycerol (hPG-NH2) crosslinked by polyethylene glycol dialdehyde (DA) hydrogel as a bone adhesive is presented in this proof-of-concept study. The hydrogel system, crosslinked by Schiff base bonds, is designed to degrade hydrolytically when applied internally. To elaborate the relationship between the crosslinker length and the material properties, three different DAs with different molecular masses were used, as well as glutaraldehyde, and also blends of those components. It was shown that the hydrogel's properties could be adjusted by application of these aldehydes and their mixtures. In general, the gelation time decreases with lower molecular mass of the dialdehyde crosslinker, whereas the gel strength increases. The hydrogel model adhesives lead to a bond strength of up to 800 kPA on bone substrates.
Traditional wound dressings lack advanced wound-healing functionalities, with added difficulties of frequent replacements. Electrospinning is an exciting avenue for fabricating biomedical dressings with improved performance. This study presents the development of a novel electrospun nanocomposite scaffold composed of sodium alginate (SA) and polyethylene oxide (PEO), crosslinked with calcium ions and subsequently coated with bacterial cellulose (BC) for prospective wound dressing applications. A post-electrospinning dip-coating strategy was employed to preserve the structural integrity of both SA and BC, addressing limitations of traditional BC-polymer composites. SEM analysis revealed uniform, bead-free nanofibers with interconnected porosity, promoting breathability and moisture exchange. FTIR confirmed functional group retention post-coating, while DSC indicated thermal stability above physiological temperatures. Mechanical testing showed a Young's modulus of 1.99 MPa and strain-at-break of 2.27%, comparable to commercial dressings such as Aquacel Extra and Kaltostat. Coating consistency was validated through thickness analysis, with over 92% retention after aqueous immersion. Solubility tests demonstrated hydrolytic responsiveness and coating stability under moist conditions. These results highlight the scaffold's mechanical resilience, structural compatibility, and process scalability. The developed SA/PEO-BC composite presents a promising, cost-effective platform for wound care. Future investigations will explore its biological activity, antibacterial performance, and in vivo efficacy for clinical translation.
Transparent wood and translucent wood are attracting attention as promising sustainable optical materials. Typically, translucent wood is prepared through chemical treatments (bleaching, etc.); thus, there is a need for more ecofriendly, sustainable preparation methods. In this study, translucent wood was prepared by precisely controlling the compression conditions. Natural wood was densified to reduce internal voids that cause light scattering, resulting in a light transmittance of more than 60% for visible light (@600 nm, sample thickness: similar to 0.3 mm). This method was particularly effective for softwood and can be applied to hardwood, accelerating the development of ecofriendly optical materials.
