ACS Applied Polymer Materials最新文献

Organic polymers featuring donor−acceptor(D-A) molecularstructures are promising photocatalysts for solar-driven H₂ production. Unfortunately, most D-A-type polymeric photocatalystsstill suffer from sluggish charge dynamics and deficient active sites.Herein, two organic porous polymers with different molecular structuresare reported using triazine ring (Tz, A₁) and dithieno[3,2-b:2′,3′-d]thiophene-S,S-dioxide (DTDO, A₂) as acceptors.Compared to TPH-DTDO with the D-A structure, TTZ-DTDO possesses anextra charge transfer channel, more active sites, and stronger chargeseparation ability due to its A₁-D-A₂ structure,achieving the dual regulation of charge dynamics and active sites.These advantages enable TTZ-DTDO to realize an excellent H₂ generation rate of 21.15 mmol h⁻¹ g⁻¹ under full arc light (320 nm < λ < 780 nm), which isapproximately 5.5 times higher than that of TPH-DTDO (3.83 mmol h⁻¹ g⁻¹), demonstrating the positiveinfluence of the A₁-D-A₂ molecular design onupgrading the photocatalytic efficiency of organic polymers.

SubmicronNaCl aerosol particles, characterized by their high penetratingability and associated environmental health risks, present a significantchallenge to conventional filtration materials. Traditional nanofibermembranes, which primarily rely on physical interception, often struggleto simultaneously achieve high filtration efficiency and low airflowresistance. To address this, we propose a strategy for the in situloading of the TpPa-1 covalent organic framework (COF) onto PVA, PAN,and PCL nanofiber membranes via needle-based electrospinning. Theresulting TpPa-1@PVA, TpPa-1@PAN, and TpPa-1@PCL composite membraneswere fabricated and systematically evaluated for their filtrationperformance against 0.3 μm NaCl aerosols. Notably, the TpPa-1@PCLcomposite membrane achieved a removal efficiency of 99.89%, alongsidea 28.05% reduction in pressure drop, yielding a quality factor of0.1157 Pa^–1. To elucidate the capture mechanismat the molecular scale, we performed CP-BSSE-corrected DFT calculationsusing the upgraded def2-TZVP basis set. The results indicate thatthe C═O group in the β-ketoeneamine structure forms astrong noncovalent interaction with Na⁺ via ion–dipoleinteractions (E_ads = −87.49 kJ/mol;verified to be −84.56 kJ/mol by ωB97X-D calculations).This interaction exceeds the threshold for physical adsorption butstill falls within the category of strong noncovalent ion–dipoleinteractions. Furthermore, NBO natural population analysis providesquantitative evidence of charge transfer (ΔqNa = −0.062e, E(2) = 78.5 kJ/mol), indicating that such transfer is largely independentof specific functional groups. Collectively, our multiscale analysesdemonstrate that the TpPa-1 composite fiber membrane effectively reducespressure drop while maintaining superior filtration efficiency, offeringrational design guidance for the development of next-generation high-performance,low-resistance air filtration materials.

High-frequency dielectric dissipation in aromatic polyimides(PIs)is generally discussed in terms of monomer polarity, while the roleof field-induced chain conformation remains less clear. In this study,statistical learning and molecular dynamics simulations under alternatingelectric fields were combined to elucidate linkage-dependent dielectricdissipation in BPDA-based PIs. A random forest model indicated thatether- and ester-containing fragments were associated with low dielectricdissipation, as identified by SHAP analysis. Guided by this result,BPDA-based PIs containing ether (BPDA-ODA), ketone (BPDA-DABP), ester (BPDA-APAB), and amide (BPDA-DABA) linkages were constructed and examined in termsof chain conformations and dielectric properties at 10 and 50 GHz. BPDA-ODA and BPDA-DABP exhibited coiled shapes,while BPDA-APAB and BPDA-DABA exhibitedextended shapes. Under alternating electric fields, the PIs with flexiblelinkages and coiled shapes exhibited symmetric expansion, while thePIs with rigid linkages and extended shapes mainly exhibited anisotropicexpansion. Compared with BPDA-ODA and BPDA-DABP, which have flexible linkages, BPDA-DABA showed thehighest induced polarization density because of its rigid, polar amidelinkage. The maximum induced polarization density indicated a strongpositive linear correlation with dielectric dissipation at 10 and50 GHz. In addition, the calculation showed that PIs with flexiblelinkages and coiled shapes exhibited larger increases in dielectricdissipation from 10 to 50 GHz than PIs with extended shapes. Thesefindings establish a molecular-level framework linking functionalizedlinkage, chain conformation, field-induced anisotropy, induced polarization,and dielectric dissipation, suggesting that PIs with low dielectricdissipation require suppressing excessive anisotropic expansion andinduced polarization under alternating electric fields.

Stimuli-responsive hybrid nanosystemshave attractedincreasingattention because they enable adaptive behavior through the integrationof multiple functional nanobuilding blocks. Herein, we report on theengineering of environment-responsive nanosystems through the developmentof reproducible and potentially scalable synthetic routes, while providinginsight into how nanoarchitecture influences their stimulus-responsebehavior. We produced multilayer core–shell copolymers colloidscomposed of three modular components: Au (plasmonic heating module),silica (providing metal stabilization and surface chemistry compatibility),and P(NIPAM-co-AA) (thermo- and pH-responsive domain).To elucidate the impact of the nanoarchitecture on the dual responsebehavior, we methodically varied the silica shell structure (denseversus mesoporous) and the copolymer architecture (cross-linked networkversus brushlike structure), enabling a systematic evaluation of howthese structural features govern stimulus-responsive behavior andtheir capability in loading and controlling molecule release. Theresulting nanosystems were monodisperse and colloidally stable, whiletheir thermo- and pH-responsive behavior could be precisely tunedthrough the silica and polymer nanoarchitecture. The nanosystems werestudied as carriers for doxorubicin (DOX), which is a well-known chemotherapeuticdrug. We demonstrated that the nanosystems efficiently loaded DOX,particularly when porous domains were present in either the silicaor polymer shell. DOX release was controlled by the combined effectsof the tumor microenvironment and plasmonic heating. In vitro assays performed on a human melanoma cell line (Mel-J) proved thatthe DOX release from the nanosystems exhibited cytotoxicity comparableto that of free DOX, reducing the cell viability to approximately50%. These findings highlight the potential of the developed smarthybrid nanosystems as an alternative strategy for DOX-based chemotherapy.

Integrating thermal and mechanical sensing into simplefiber platformsremains challenging because of cross-influence between sensing channels.Here, a fiber-shaped bimodal temperature-mechanical sensor is developedby combining a thermoresponsive SEBS/acrylate copolymer (AC)/carbonblack (CB) conductive core with a silicone rubber dielectric shelland an orthogonally crossed-fiber architecture. The composite coreprovides a pronounced positive temperature coefficient (PTC) response,while deformation of the crossed junction enables capacitive forcesensing. The sensor operates over 25–45 °C and 0.0025–0.98N. Quantitative analysis shows that resistance is predominantly governedby temperature, whereas capacitance is influenced by both temperatureand force. A temperature-dependent baseline correction improves forcediscrimination, although residual thermal-mechanical coupling remains.Repeated thermal and DSC cycling demonstrate reproducible sensingand phase-transition behavior. A localized thermal-touch demonstrationfurther verifies simultaneous thermal and mechanical sensing, highlightingthe potential of this compact fiber platform for textile-integratedthermal-touch applications.

Lightweight elastomeric composites with tunable viscoelasticresponseare essential for advanced energy-management cushioning applications.However, achieving controlled modulation between damping and elasticrecovery remains challenging in silicone-based polymeric systems.Herein, polydimethylsiloxane (PDMS) was structurally engineered througha synergistic multiphase approach encompassing: (i) reinforcementwith collagen fibers (CF) derived from leather waste, (ii) incorporationof polyphenylmethylsiloxane (PPMS) to modulate segmental dynamics,and (iii) surfactant-assisted (S) morphological control. This integratedstrategy enabled systematic regulation of composite density, mechanicalcompliance, and cyclic hysteresis behavior, offering a route to tunableviscoelastic response in silicone-based systems. Scanning electronmicroscopy revealed a highly porous structure with uniform sphericalpores in the optimized CF-PD-PP-S composite, while magnetic resonanceimaging confirmed a partially open-cell structure with enhanced poreaccessibility throughout the bulk. X-ray photoelectron spectroscopyverified the successful incorporation of collagen fibers, PPMS, andsurfactant, indicating optimal formulation. The progressive modificationinduced a transition from damping-dominant to resilience-dominantmechanical response, with the optimized CF-PD-PP-S composite exhibitinglow hardness (26 ± 2 Shore OO), reduced density (0.55 g/cm³), controlled cushioning energy (128–205 mJ), minimalcompression set (2.77%), and stable cyclic recovery (85% resilience;15% dissipation). The reduced hysteretic loss during repeated short-termloading suggests that the composite retained a stable mechanical responseafter repeated loading. The results establish a materials design strategyfor tailoring energy dissipation and recovery balance in PDMS-basedelastomeric composites for footwear cushioning applications.

Accessing telechelic polymers from renewable resourcescan be challengingbut is nonetheless an essential goal as we increase sustainabilityin polymer and materials science. With this objective, we report theanionic oligomerization of biobased myrcene using a versatile dilithiatedinitiator. Use of the dilithiated initiator in a microflow reactorresulted in excellent control over the polymerization as well as thetrapping of various electrophilic species (aldehyde, ketone, imine,amide, disulfide, and carbon dioxide) in liquid or gas phase, witha high functionalization degree to afford end-capped telechelic oligomerswith α,ω-dihydroxy, amino, carbonyl, sulfide, and carboxylicacid functionality.

Sulfur-containingpolymers, especially those with sulfur in themain chain, have attracted significant interest owing to their diversestructures and unique properties, making them promising candidatesfor solid-state electrolytes. However, their controllable synthesisin metal-free catalysis remains challenging. Herein, a poly(propylenecarbonate-co-thioether-co-ether)(PPCTE) terpolymer was synthesized by a one-step copolymerizationof carbon dioxide (CO₂), epoxides, and ethylene sulfide(ES) in a metal-free catalytic system. The PPCTE polymers with high-sulfursegments of 5% content in the main chain (PPCTE_0.05) wereobtained by regulating the monomer concentration ratio and the typesof metal-free catalysts, yielding molecular weights of 27 kg mol^–1. PPCTE_0.05 exhibits a relatively low glasstransition temperature of 5.8 °C, good thermal decompositionstability with 5% mass loss at 190 °C, and excellent flexibilityof 647% elongation at break. Notably, the PPCTE_0.05-basedsolid-state polymer electrolyte achieves a low impedance of 99 Ω,high ionic conductivities (5.36 × 10^–5 S cm^–1 at room temperature, 1.77 × 10^–4 S cm^–1 at 60 °C), a low activation energyof 0.29 eV, and a wide electrochemical window of 5.21 V. This workestablishes a simple, economical, and eco-friendly synthetic routefor main-chain sulfur-containing polymers and offers a valuable referencefor designing solid-state polymer electrolytes.

The integration of nanozyme-based catalytic activityinterventionswithin the tumor microenvironment (TME) with phototherapies representsa promising approach for triggering multimodal synergistic cancertherapy. Herein, a protein-mineralized nanozyme was fabricated via in situ biomineralization, utilizing iron ions coordinatedwith glucose oxidase (GOx-Fe). Unlike traditional nanozyme systemsthat rely on passive targeting or a single catalytic function, thedesign uniquely integrates a cascade therapeutic system within a singlebiocompatible platform. This nanozyme possesses dual catalytic propertiesto facilitate glucose oxidation and the conversion of hydrogen peroxide(H₂O₂) into hydroxyl radicals (•OH) andoxygen (O₂). This dual-catalytic mechanism establishesa self-augmenting cascade that concurrently activates starvation therapy(ST) and chemodynamic therapy (CDT) within a signal nanosystem. Toachieve tumor-specific delivery, the GOx-Fe nanozyme was modifiedwith a polymer consisting of Chlorin e6-functionalized PEGylated hyaluronicacid (mHDC). The resulting GOx-Fe@mHDC nanozyme exhibits a uniformspherical morphology with an average hydrodynamic diameter of approximately50 nm and a negative surface charge of about −19 mV. It maintainsstability across diverse physiological environments but undergoesactivation in the enzyme-rich TME, ensuring targeted and selectivetherapeutic effects. The nanozyme demonstrates efficient glucose consumption(approaching the performance of free GOx) and significant intracellularH₂O₂ generation (290% higher than free GOx),leading to enhanced •OH production and O₂ self-supply.In A549 tumor-bearing mice, intravenous administration of GOx-Fe@mHDCfollowed by 660 nm laser irradiation resulted in marked tumor growthinhibition (tumor weight suppression rate of 86%) with negligiblesystemic toxicity. Importantly, the developed GOx-Fe@mHDC system exhibitedstrong catalytic stability, targeted tumor accumulation, effectiveendolysosomal escape, selective cytotoxicity, and substantial in vivo tumor suppression with excellent biosafety. Thisresearch introduces a versatile biomineralization technique for constructingFe-based nanozymes with dual catalytic and tumor-specific capabilities,offering a scalable approach for advancing cancer therapeutics.

Theimproved platelet adhesion resistance of fluorinated polyurethane(PU) is often attributed to the fluorination-induced surface hydrophobicity.Here, we show that superior platelet adhesion resistance can be achievedwith limited changes in the apparent surface hydrophobicity as well.Dual-anchored fluorinated polyurethane prepolymers (FPUPs) with differentnominal fluorocarbon-site densities were synthesized and blended witha biomedical PU matrix. X-ray photoelectron spectroscopy (XPS) showedthat the surface fluorine content varied from 8.7 to 37.3% acrossthe formulations, whereas most films exhibited static water contactangles comparable to the value for the PU matrix. Thus, variationsin the FPUP architecture were associated with substantial differencesin surface composition without proportional changes in the staticwater contact angle. Among the tested formulations, FPUP35 exhibitedthe most favorable overall biointerfacial performance: FPUP35–5.0reduced long-term fibrinogen (Fib) adsorption by 44.4%; FPUP35–2.5reduced platelet adhesion density by 69%, and platelet morphologieson the fluorinated surfaces were qualitatively consistent with reducedactivation-associated spreading; FPUP35–7.5 also exhibitedan HUVEC/L929 adhesion ratio of 1.85 after 24 h in separate monocultures.These results indicate that biointerfacial performance does not simplycorrelate with surface fluorine content but is associated with overallFPUP architecture, including nominal fluorocarbon-site density andcovarying molecular weight and segment composition. Nominal fluorocarbon-sitedensity is therefore a potentially useful component of the moleculardesign space for platelet-adhesion-resistant PU surfaces.