The insufficient interfacial adhesion between carbon fibers and the PEEK matrix remains a key obstacle to realizing the full mechanical and thermal performance of CF/PEEK composites. This work proposes a biphenyl-containing branched poly(aryl-ether-nitrile) (BPEN) with controlled branching degree as an interfacial compatibilizer and subsequently processed with PEEK via a powder-impregnation assisted hotpressing method to fabricate CF@BPEN/PEEK laminated composites. When the BPEN branching degree is 10 %, the CF@BPEN/PEEK laminated composites exhibit interlaminar shear strength of 39.7 MPa and a flexural strength of 506.5 MPa, which are 66.1 % and 39.2 % higher than pristine CF/PEEK laminated composites (23.9 and 363.9 MPa), respectively. In addition, the modified laminated composites show enhanced thermal conductivity (1.45 W m-1 K-1), an elevated glass transition temperature by approximately 4 degrees C, and a remarkable X-band electromagnetic interference shielding effectiveness of 41.0 dB. These multifunctional enhancements originate from a robust, diffusion-driven interphase, constructed through pi -pi stacking interactions between BPEN biphenyl units and PEEK chains, as well as hydrogen bonding between cyano groups and oxygen-containing sites on the fiber surface. Furthermore, the polarization induced by the strong polar BPEN structure contributes to effective EMI performance. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Constructing ordered thermally conductive pathways within polymer-based composites can optimize heat transfer routes, thereby significantly enhancing the thermal conductivity of the composites. In this work, polydimethylsiloxane (PDMS) was employed as the matrix, while magnetically responsive boron nitride nanosheets (BNNS@Ni) and surface-functionalized gallium-indium liquid metal (f-LM) were utilized as hybrid thermally conductive fillers to fabricate H-‍BNNS@Ni/f-LM/PDMS composites with bidirectional thermally conductive pathways in both the in-plane and through-plane directions via magnetic field orientation. At a H-BNNS@Ni to f-LM mass ratio of 4:1 and a total filler loading of 50 wt%, the in-plane thermal conductivity (λ∥) and through-plane thermal conductivity (λ⊥) of the H-‍BNNS@Ni/f-LM/PDMS composites reached 6.31 W/(m·K) and 0.98 W/(m·K), corresponding to 33.2 and 9.8 times those of pure PDMS, respectively. The H-BNNS@Ni/f-LM/PDMS composites also exhibited outstanding thermal stability (thermal resistance index of 261.8°C), photothermal conversion capability (surface temperature reaching 161.4°C after 30 s of near-infrared light irradiation at 0.95 W·cm−2), and hydrophobicity (water contact angle of 120.0o), indicating their considerable potential for applications in next-generation flexible electronic devices.

Polyimide (PI) films are limited by the low intrinsic thermal conductivity (lambda) during their application in flexible electronics. This work proposes a strategy to enhance the intrinsic lambda of PI by regulating the aggregation structure. Highly crystalline PI films with improved intrinsic lambda are synthesized by optimizing the molar ratio of 4,4-oxydiphthalic anhydride (ODPA) to pyromellitic dianhydride (PMDA). At an ODPA to PMDA molar ratio of 1:9, the PI film crystallizes from solution and further develops during thermal imidization, exhibiting uniform spherulite distribution with the crystallinity up to 35.8%, 5.4 times higher than that of conventional PI films (5.6%). The in-plane lambda (lambda parallel to ) and through-plane lambda (lambda perpendicular to ) of the highly crystalline PI film reach 2.58 and 0.18 W/(mK), respectively, significantly higher than those of conventional low-crystallinity PI films (1.65 and 0.09 W/(mK)). The highly crystalline PI film also exhibits excellent mechanical properties, demonstrating great potential for advanced flexible electronics.

Electromagnetic wave absorbing materials (EMWAMs) are evolving from conventional passive electromagnetic (EM) absorber toward multifunctional and intelligent regulation systems to meet the demands of increasingly complex EM environments and application...

Aromatic polyesters are widely used in microelectronics, medical devices, and new-energy vehicle batteries. However, their low intrinsic thermal conductivity (λ) limits their effectiveness in dissipating heat from high-power components. Intermolecular interactions such as hydrogen bonds and π-π stacking are effective for enhancing the λ of aromatic polyesters. In this work, 5-(n-alkoxy-Cam-AmBiph)IPA (IPA) with an amide bond, biphenyl unit and varying-length alkyl is synthesized first. Three types of intrinsically thermally conductive side-chain poly(4,4′-dihydroxybiphenyl isophthalate) (S-PDI) are prepared using IPA and 4,4′-biphenol as the main monomers through solution polycondensation and “solution coating-stacking-hot pressing” process. The results demonstrate that the length of the side-chain alkyl spacer effectively controls the hydrogen-bond density. The seven-methylene spacer promotes the densest hydrogen-bonding network in S-PDI, and the combined effect of hydrogen bonding and π-π stacking thus significantly enhances its intrinsic thermal conductivity. The highest λ of S-PDI reaches 0.36 W/(m K), representing a 140.0

As electronic devices trend toward miniaturization and higher performance, effective heat dissipation and electromagnetic interference suppression have become critical challenges. The development of thermally conductive/microwave absorption polymer composites is urgently required. In this work, carbon nanotube (CNT) is grown in-situ on Co-C surface through pyrolysis of thermally robust, large-particle zeolitic imidazolate framework-67 (ZIF-67) and melamine (MF). The obtained core-shell Co-C@CNT is blended with a self-synthesized side-chain poly(4, 4′-dihydroxybiphenyl isophthalate) (S-PDI) to prepare Co-C@CNT/S-PDI composites using “solution coating-stacking-hot pressing” process. When the MF:ZIF-67 mass ratio is 1.5:1, an optimal core-shell morphology and the highest thermal conductivity of Co-C@CNT are achieved. 25 wt% Co-C@CNT/S-PDI composites exhibit thermal conductivity of 0.84 W/(m·K), which is 133.3% higher than that of S-PDI (0.36 W/(m·K)). Moreover, corresponding minimum reflection loss, elasticity modulus and heat resistance index reach −53.8 dB (8.08 GHz), 5.3 GPa and 185.0 °C, respectively.

The development of intelligent electromagnetic skins demands scalable films integrating gigahertz (GHz)-terahertz (THz) wave absorption, electromagnetic interference (EMI) shielding, and programmable actuation. Here, we report a bioinspired bamboo-like layered-gradient system fabricated via scalable vacuum filtration, in which two types of films are constructed with distinct functionalities: a low-poly(3,4-ethylenedioxythiophene) (PEDOT) content film for microwave absorption and a high PEDOT content film for conductive network-enabled EMI shielding.The films precisely assemble Al-Fe3O4 nanosheets, aramid nanofibers, and PEDOT into an asymmetric architecture. A monotonic through-thickness gradient in composition creates a tailored impedance profile and strong anisotropy while minimizing conductive filler content. This design achieves effective microwave absorption at low PEDOT loading (minimum reflection loss: − 56.6 dB at 2.2 mm in the X-band). With increased PEDOT content, a percolative network is constructed, enabling Joule heating (233 °C at 20 V) and efficient EMI shielding (42.0 dB in the GHz band and 57.8 dB in the THz band). Beyond electromagnetic performance, the gradient architecture enables programmable, ethanol-triggered anisotropic actuation via differential swelling. The films also exhibit excellent thermal stability, mechanical robustness, and flexibility, ensuring reliability in harsh environments. Collectively, this gradient architecture provides a scalable platform for intelligent electromagnetic skins integrate magnetic-dielectric coupling, conductive network tuning, and stimuli-responsive actuation.

With the extensive production of current multifarious electronic devices, corresponding electromagnetic pollution issues have been increasingly exacerbated. In response to these challenges, herein, VS2 nanorods were uniformly grafted on graphene nanosheets (GNSs) fabricated through a facile ball milling method to construct 1D/2D hierarchical VS2@GNSs composites with terrific electromagnetic wave (EMW) absorption properties. Specifically, the minimal reflection loss (RLmin) of VS2@GNSs composites could reach −49.83 dB at 1.83 mm, and an ultra-broad effective absorption bandwidth (EAB) of 6.72 GHz was attained when the matching thickness was 1.96 mm, attributable to the distinguished impedance matching characteristics and EMW attenuation capacities of 1D/2D VS2@GNSs composites. In addition, computer simulation technology (CST) full-wave simulation further confirmed VS2@GNSs composites manifested remarkable radar scattering cross-section (RCS) suppression in real-world application scenarios, with the RCS reduction value of up to 20.38 dB m2 compared to metallic substrate. This work proposed the theoretical instruction and experimental basis for the design and fabrication of high-performance stealth materials.

ABSTRACT Polymer‐based electromagnetic interference (EMI) shielding composite fibers have gradually become a research hotspot in the field of EMI shielding due to their advantages of being lightweight, corrosion‐resistant, highly flexible, and easily weavable. This review focuses on the preparation strategies of polymer‐based EMI shielding composite fibers, systematically reviewing the research progress and characteristics of wet spinning, electrospinning, and other methods such as chemical deposition and template methods. Starting from the structural design principles of fibers, it specifically analyzes the construction strategies, preparation methods, and development status of solid, core–shell, and hollow structures of polymer‐based EMI shielding composite fibers. It summarizes the effects of different preparation processes and structural morphologies on the EMI shielding performance and mechanical properties of polymer‐based EMI shielding composite fibers, identifies key scientific and technical issues that need to be resolved in current preparation methods, and looks ahead to the future development trends of polymer‐based EMI shielding composite fibers. This review aims to provide theoretical guidance for the innovation of preparation strategies and performance improvement of polymer‐based EMI shielding composite fibers, promote their applications in aerospace, smart wearables, medical electronics, and other fields, and open up new directions for the development of electromagnetic protection materials.

Cross-wavelength near-perfect light capture technology is crucial in various fields, including spectroscopy, energy conversion, and electromagnetic control. Nevertheless, the primary challenge in broadband absorption is effectively coordinating the intrinsic response behavior of various electromagnetic waves across the nanometer-centimeter scale when interacting with matter. By adopting a multi-scale structural design strategy, the carbon-zirconium heterointerface is integrated into the macroscopic periodic unit cell (PUC) to develop an ultra-wideband light capture material. The optical coupling effect, strengthened by electronic transitions, molecular motion, and spatial scattering effects, endows ZC-PUC with exceptional light-capture performance ranging from ultraviolet to microwave frequencies. Specifically, the ZC-PUC absorber possesses a near-perfect absorption rate of 95.7

The rapid expansion of the low-altitude economy has driven growing demand for carbon fiber/epoxy composites in applications including unmanned aerial vehicles and electric vertical take-off and landing aircraft. However, the characteristically low through-plane thermal conductivity (lambda perpendicular to) of these composites poses a critical thermal conduction limitation, which adversely affects the performance and reliability of onboard electronic systems. In this work, we present an architectural design to improve the lambda perpendicular to of mesophase pitch-based carbon fiber (MPCF)/epoxy composites by incorporating precisely engineered spherical thermally reduced graphene (s-TRG) as a bridging filler. At a loading of 10 wt% s-TRG and 60 wt% MPCF, the MPCF/s-TRG/epoxy composite achieves a lambda perpendicular to of 2.73 W m-1 K-1, representing a 173.0% improvement over the MPCF/epoxy composite (1.00 W m-1 K-1) and about 1.71 times the lambda perpendicular to of its conventional TRG-filled analogue (1.60 W m-1 K-1). Monte Carlo simulations reveal that the enhancement originates from the isotropic spherical architecture of s-TRG, which facilitates efficient multi-point bridging within the three-dimensional interlaminar space, thereby overcoming the limited through-plane contact characteristic of planar graphene sheets. This work not only provides an efficient filler structural design strategy for thermal enhancement but also suggests a feasible route toward managing heat in high power density electronics for next-generation lightweight low-altitude aircraft.image

Carbon fibers (CF)/epoxy composites are widely utilized in aerospace and transportation due to their light weight and high specific strength/modulus. However, poor interfacial binding between CF and the epoxy matrix leads to phonon scattering and inefficient load transfer, causing heat accumulation and reduced service life in high-power electronic systems. In this study, CF was coated with a styrene, benzocyclobutene, and methyl methacrylate units containing polymer layer mixed with carbon nanotubes (CNT) through impregnation and drying. The polymer layer was then thermally crosslinked to obtain the polymer and CNT coated CF (CF@(CNT/P)). CF@(CNT/P) was then applied as reinforced fibers and epoxy resin containing a liquid crystal structure as the matrix to prepare CF@(CNT/P)/epoxy composites. The π-π interactions and hydrogen bonds between CF and epoxy resin were enhanced by the benzene ring and ester groups in the polymer, thereby improving the interfacial binding between epoxy resin and CF. CF@(CNT/P)/epoxy composite showed enhanced load-bearing and thermal conduction performance. When the mass fractions of CNT and copolymer in CNT/P/dichloromethane (DCM) solution were 0.03 wt% and 0.1 wt%, respectively, the CF@(CNT/P) had the best interfacial binding to the epoxy resin. The interlaminar shear strength and flexural strength of the CF@(CNT/P)/epoxy composite increased from 23.7 and 252.5 MPa of CF/epoxy composite to 31.4 and 369.1 MPa, respectively. Meanwhile, the in-plane (λ∥) and through-plane (λ⊥) thermal conductivity values were improved from 7.15 and 0.31 W/(m·K) of CF/epoxy composite to 10.08 and 0.58 W/(m·K), respectively. The CF@(CNT/P)/epoxy composite also demonstrated an electromagnetic interference shielding effectiveness of 38.6 dB which has broad application in high-power electronic information systems.

Highly thermally conductive polymers are playing essential roles in various electronics-related fields. However, the mechanism underlying thermal conduction remains hitherto elusive. Herein, the intrinsic thermal conduction mechanism of polymers is disclosed by rational molecular structural design and precise synthesis through reversible addition-fragmentation chain transfer (RAFT) polymerization. By precisely controlling the spatial distribution and sequence of the cyanobiphenyl-based liquid crystalline (LCx) monomer and glycidyl methacrylate (GMA, epoxy-containing unit), as well as the length of the flexible segment (-CH2-) x in LCx, block copolymers PLCx m -b-PGMA n with multi-level long-range ordered structures were generated. Specifically, hexagonally packed cylinder-like (HEX-like), lamellar-like (LAM-like), and inverted hexagonally packed cylinder-like (inverted HEX-like) microstructures were effectively constructed as the flexible segment of -CH2- was increased to 11 ((-CH2-)11, LC11). It is noteworthy that increasing the ratio of LC11 was highly beneficial for enhancing thermal conductivity. Moreover, compared with HEX-like and inverted HEX-like morphologies, which exhibited numerous thermal interfaces, the LAM-like morphology was able to construct long-range phonon transport pathways and reduce phonon scattering through the synergistic effect of microphase separation-driven confined assembly with a semicrystalline structure and supramolecular assembly, thereby exhibiting higher thermal conductivity. This study elucidates the thermal transport mechanism at molecular levels by experiments and simulations, highlighting the crucial role of multiscale chain alignment and long-range ordered structures synergistically enhancing phonon propagation in polymers.

Thermal management smart windows can regulate indoor temperature by adjusting the intensity or spectral distribution of incoming solar radiation. This functionality helps reduce the energy demand of heating, ventilation, and air-conditioning (HVAC) systems, thereby contributing to energy conservation, emission reduction, and the achievement of carbon neutrality. Thermochromic hydrogels, with their intrinsic temperature responsiveness, broadband optical modulation capability, facile tunability, and low cost, have become ideal thermochromic materials for thermal management smart windows. This review focuses on thermochromic hydrogels for thermal management smart windows and introduces the research progress of intrinsic thermochromic hydrogels and their thermal management smart windows from the perspectives of chemical modification strategies and physical modification strategies. Then, the research progress of composite thermochromic hydrogels and their applications in thermal management smart windows is systematically reviewed, with particular emphasis on the incorporation of photothermal conversion fillers and thermochromic components. Moreover, current challenges and potential improvement strategies of thermochromic hydrogels for thermal management smart windows are identified and discussed. The aim of this review is to systematically summarize the optimization strategies for thermochromic hydrogels in thermal management smart windows and to provide guidance for future in-depth research, thereby promoting the advancement and application of thermochromic hydrogels for smart windows.

The rapid rise in chip heat generation places increasing demands on thermal interface materials (TIMs), requiring higher thermal conductivity and more efficient thermal conduction pathways. Here, we introduce a new design strategy for TIMs that directs heat transfer in three stages: horizontal distribution, vertical transfer, and horizontal dissipation. Using the direct ink writing three-dimensional printing technique, we fabricate polydimethylsiloxane (PDMS)-based TIMs with a colonnade-inspired architecture. The top and bottom “corridors” are formed from a boron nitride nanosheet (BNNS)/PDMS composite, where BNNS fillers are aligned in the in-plane direction to enhance lateral heat conduction. The central “pillar” layer is composed of a reduced graphene oxide (rGO)/PDMS composite, with rGO fillers aligned in the through-plane direction to promote vertical heat transfer. Compared with conventional PDMS-based TIMs containing randomly dispersed fillers or sandwich structures with only in-plane alignment, our prepared colonnade-structured PDMS-based TIMs demonstrate significantly improved thermal conductivity and reduced thermal resistance for interfaces.

With the rapid development of highly integrated and miniaturized electronic components, heat accumulation and signal attenuation in devices have become increasingly prominent. This underscores the urgent need to develop polymer-based composite paper with high thermal conductivity and low dielectric constant ( s). In this work, a PBO-analog compound (prePBO) is designed to functionalize boron nitride nanosheets (f-BNNS). Simultaneously, poly(p-phenylene-2,6-benzobisoxazole) (PBO) fibers are converted into PBO nanofibers (PNF) via deprotonation. Subsequently, the f-BNNS/PNF nanocomposite paper is fabricated via vacuum filtration followed by hot pressing. The prePBO enhances interactions between PNF and BNNS, reducing interfacial thermal resistance and suppressing interfacial phonon scattering. At 50 wt% f-BNNS loading, the f-BNNS/PNF nanocomposite paper achieves optimal thermal conductivities (?|| = 10.37 W/(m K), ?perpendicular to= 0.86 W/(m K)), representing 414 % and 480 % improvements over pristine PNF paper. Furthermore, due to the ultralow polarizability of fluorinated groups in prePBO and the nacre-mimetic structure, the nanocomposite paper presents low s (3.15) and dielectric loss tangent (tans, 0.0221) at 1 MHz, alongside a volume resistivity of 3.3 x 1015 Q cm and breakdown strength of 155.6 kV/mm. The nanocomposite paper also exhibits high tensile strength (114.55 MPa) and thermal decomposition temperature (640 degrees C), demonstrating promising potential for thermal management in high-power lithium batteries, ultrahigh-voltage capacitors, and related advanced applications. (c) 2025 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

As electronic devices and communication technologies continue to advance, the issue of electromagnetic pollution has become more pronounced. Consequently, there is an urgent requirement for electromagnetic interference (EMI) shielding composites characterized by a low reflection coefficient (R). In this work, MXene/graphene oxide/bacterial cellulose (BC) composite foams (MGCF) featuring a multilayer structure were successfully constructed via layered freezing combined with freeze-drying technology. The multilayer structure of MGCF effectively attenuates electromagnetic waves (EMWs) through a synergistic effect. Specifically, the top impedance matching layer guides EMWs into MGCF, the intermediate absorption layer dissipates the majority of electromagnetic energy as heat via dielectric loss, and the bottom highly conductive reflection layer reflects the transmitted EMWs back to the middle absorption layer. Through this sequential ‘matching–absorption–reflection’ mechanism, electromagnetic energy is thoroughly attenuated, leading to outstanding EMI shielding performance coupled with a minimized R. Due to its unique multilayer structure, MGCF exhibits an EMI shielding effectiveness (SE) of 54 dB, maintaining the R value within the range of 0.22 to 0.38. Moreover, MGCF exhibits an exceptionally low thermal conductivity (λ) of merely 59.58 mW·m ^–1 ·K ^–1 , meeting insulating requirements. Additionally, MGCF can autonomously transition between infrared stealth and infrared response states. The surface temperature of the MGCF during the hot stage at 100 ℃ is only 44.3 ℃. When exposed to simulated solar irradiation at a power density of 120 mW·cm ^–2 , the surface temperature of the MGCF swiftly increased from ambient temperature to 69 ℃. This work presents a novel approach to designing biopolymer composites with excellent shielding performance and minimal reflection, and accelerates the evolution of EMI shielding materials designed for adaptive applications, particularly in radar stealth, infrared camouflage and thermal insulation.

The fast-evolving IT sector necessitates intelligent electromagnetic interference (EMI) shielding materials capable of real-time, environment-responsive. While current approaches based on reconstructing conductive networks through mechanical strain enable dynamically responsive shielding, but face a narrow tuning range, inadequate stability, and practical limitations. To address this, we propose an electric/magnetic field synergistic regulation strategy. This approach enables precise control over the alignment angle between reduced graphene oxide (rGO) and nickel nanowires (NiNWs) by manipulating the external field direction, producing rGO@NiNWs/polyimide aerogels with 3D ordered networks. Leveraging this design, the aerogels achieve reversible, wide-range tuning of EMI shielding performance through simple physical rotation, enabling reliable "on/off" switching capability. The oriented structure also optimizes both filler interconnection efficiency and interfacial polarization. With an rGO@NiNWs content of 80 wt.% and an inter-phase angle of 90°, the aerogels demonstrate excellent ultra-wideband EMI shielding performance across gigahertz and terahertz bands, with an average shielding effectiveness of 85 dB in the terahertz band, alongside good stability in extreme environments. Finite element simulations further reveal how the spatial configuration of rGO@NiNWs governs the shielding behavior and intelligent response mechanism. This study paves the way for next-generation intelligent electromagnetic protection materials, with promising potential for aerospace and wearable applications.

The alignment angle and distribution of thermal conduction pathways are key structural parameters for regulating the thermal conductivity of polymer composites. However, their intrinsic quantitative influence on thermal conductivity remains unclear, limiting the rational structural design and performance optimization of thermally conductive composites. Herein, two-dimensional (2D) copper wire (Cw)/PLA composites were fabricated via 3D printing, in which Cw thermal conduction pathways were embedded within the poly(lactic acid) (PLA) matrix with controllable pathway alignment angle and distribution. The results show that the in-plane thermal conductivity coefficient (lambda(//)) of 2D Cw/PLA composites is positively correlated with the Cw pathway alignment angle theta (0 degrees <= theta <= 90 degrees) and the distribution uniformity factor K (0 <= K <= 1). When the Cw volume fraction is 12.6 vol%, and the Cw pathways are orthogonally aligned (theta = 90 degrees) with uniform distribution (K = 1), the lambda(//) increases to 3.65 W/(m K), which is 40.9 % higher than that of the composites (2.59 W/(m K)) with parallel Cw pathways (theta = 0 degrees) and completely non-uniform distribution (K = 0), and approximately 14 times that of pure PLA (0.26 W/(m K)). Based on the optimized geometric mean thermal conductivity model, a quantitative relationship was established linking theta and K with the lambda(//) of the 2D Cw/PLA composites. The average ratio of the theoretically predicted lambda(//) to the experimentally measured lambda(//) is 1.04, validating the quantitative influence of thermal conduction pathway alignment angle and distribution uniformity on the thermal conduction behavior of the composites. This study deepens the understanding of how thermal conduction pathway geometry governs heat conduction in polymer composites and provides both theoretical and practical guidance for the rational design of thermally conductive composites.