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Multifunctional materials with high electromagnetic interference (EMI) shielding effectiveness and thermal conductivity (TC) are an essential guarantee for the rapid advancement of next-generation electronic products. Herein, the three-dimensional porous conductive/thermal network of carbon nanotubes (CNT)/cellulose is prefabricated by "solution-gelation-solvent exchange-freeze drying". Using "impregnation and high-pressure compression molding", CNT/cellulose-boron nitride/polyvinyl alcohol (CNT/cellulose-BN/PVA) composite films with three-dimensional dual-continuous network structure are constructed to provide a perfect pathway for both electrons and phonons transportation. Comprehensive performance of the composites before and after hot-pressing including the microstructure, electrical conductivity, EMI shielding and thermal conductivity is investigated. Benefiting from the high-pressure compression molding process, the composite is densified and a close contact between fillers is achieved, which effectively improves the electrical and thermal conductivity. The finally obtained CNT/cellulose-BN/PVA composite film exhibits satisfactory EMI shielding performance, high in-plane and cross-plane TC, as well as excellent Joule heating performance, demonstrating enormous potential as high-performance EMI shielding and thermal management materials in practical applications. The significance of this work is to give an inspiration for improving the comprehensive performance of electromagnetic shielding and thermal conductive materials. [ABSTRACT FROM AUTHOR]

Highlights: A multi-scale conductive network was constructed in flexible PDMS/Ag@PLASF/CNT composite with micro-size Ag@PLASF and nano-size CNT. The PDMS/Ag@PLASF/CNT composite showed outstanding electrical conductivity of 440 S m-1 and superior electromagnetic interference shielding effectiveness of up to 113 dB. The PDMS/Ag@PLASF/CNT composites owned good retention (> 90%) of electromagnetic interference shielding performance even after subjected to a simulated aging strategy or 10,000 bending-releasing cycles. Highly conductive polymer composites (CPCs) with excellent mechanical flexibility are ideal materials for designing excellent electromagnetic interference (EMI) shielding materials, which can be used for the electromagnetic interference protection of flexible electronic devices. It is extremely urgent to fabricate ultra-strong EMI shielding CPCs with efficient conductive networks. In this paper, a novel silver-plated polylactide short fiber (Ag@PLASF, AAF) was fabricated and was integrated with carbon nanotubes (CNT) to construct a multi-scale conductive network in polydimethylsiloxane (PDMS) matrix. The multi-scale conductive network endowed the flexible PDMS/AAF/CNT composite with excellent electrical conductivity of 440 S m−1 and ultra-strong EMI shielding effectiveness (EMI SE) of up to 113 dB, containing only 5.0 vol% of AAF and 3.0 vol% of CNT (11.1wt% conductive filler content). Due to its excellent flexibility, the composite still showed 94% and 90% retention rates of EMI SE even after subjected to a simulated aging strategy (60 °C for 7 days) and 10,000 bending-releasing cycles. This strategy provides an important guidance for designing excellent EMI shielding materials to protect the workspace, environment and sensitive circuits against radiation for flexible electronic devices. [ABSTRACT FROM AUTHOR]

This study has developed a carbon nanotube (CNT)/ethylene vinyl acetate (EVA)/ultrahigh molecular weight polyethylene (UHMWPE) composite with a unique double percolated conductive structure, in which only 20 wt% of CNT enriched EVA is needed to form a continuous conductive network. Compared with conventional double percolated conductive polymer composites (CPCs) which require filler-enriched polymer content up to 50 wt%, the low CNT/EVA content gives rise to an unprecedentedly increased effective CNT concentration in the CNT/EVA/UHMWPE composite. The double percolated composite exhibits electrical conductivity comparable to that obtained in CNT-loaded single EVA composite with five times of CNT content. Only 7.0 wt% CNT gives the composite an electromagnetic interference (EMI) shielding effectiveness of 57.4 dB, much higher than that of mostly reported CNT and graphene based CPCs. Absorption is demonstrated to be the primary shielding mechanism due to the numerous interfaces between UHMWPE domains and CNT/EVA layers facilitating multiple reflection, scattering, and absorption of the incident microwaves. The construction of unique double percolated structure in this work provides a promising strategy for developing cost-effective and high-performance CPCs for use as efficient EMI shielding materials. [ABSTRACT FROM AUTHOR]

A high-performance electromagnetic interference shielding composite based on reduced graphene oxide (rGO) and polystyrene (PS) is realized via high-pressure solid-phase compression molding. Superior shielding effectiveness of 45.1 dB, the highest value among rGO based polymer composite, is achieved with only 3.47 vol% rGO loading owning to multi-facet segregated architecture with rGO selectively located on the boundaries among PS multi-facets. This special architecture not only provides many interfaces to absorb the electromagnetic waves, but also dramatically reduces the loading of rGO by confining the rGO at the interfaces. Moreover, the mechanical strength of the segregated composite is dramatically enhanced using high pressure at 350 MPa, overcoming the major disadvantage of the composite made by conventional-pressure (5 MPa). The composite prepared by the higher pressure shows 94% and 40% increment in compressive strength and compressive modulus, respectively. These results demonstrate a promising method to fabricate an economical, robust, and highly efficient EMI shielding material. [ABSTRACT FROM AUTHOR]

An in situ thermally reduced graphene/polyethylene conductive composite with a segregated structure was fabricated, which achieved a high electromagnetic interference shielding effectiveness of up to 28.3–32.4 dB at an ultralow graphene loading of 0.660 vol.%. Our work suggests a new way of effectively using graphene. [ABSTRACT FROM AUTHOR]

An efficient electromagnetic interference (EMI) shielding paper with excellent water repellency and mechanical flexibility has been developed, by assembling silver nanowires (AgNWs) and hydrophobic inorganic ceramic on the cellulose paper, via a facile dip-coating preparation. Scanning electron microscope (SEM) observations confirmed that AgNWs were interconnected and densely coated on both sides of the cellulose fiber, which endows the as-prepared paper with high conductivity (33.69 S/cm in-plane direction) at a low AgNW area density of 0.13 mg/cm2. Owing to multiple reflections and scattering between the two outer highly conductive surfaces, the obtained composite presented a high EMI shielding effectiveness (EMI SE) of up to 46 dB against the X band, and ultrahigh specific EMI SE of 271.2 dB mm–1. Moreover, the prepared hydrophobic AgNW/cellulose (H-AgNW/cellulose) composite paper could also maintain high EMI SE and extraordinary waterproofness (water contact angle > 140°) by suffering dozens of bending tests or one thousand peeling tests. Overall, such a multifunctional paper might have practical applications in packaging conductive components and can be used as EMI shielding elements in advanced application areas, even under harsh conditions. [ABSTRACT FROM AUTHOR]

The utility of current electromagnetic interference (EMI) shielding textiles (EMISTs) for protecting the human body from high‐intensity electromagnetic radiation is limited by their high cost, low manufacturing efficiency, and poor stability under mechanical deformation. More importantly, no existing EMISTs are truly washable, which is critical for optimized protection with direct and conformal contact with human skin. In this paper, by integrating silver nanowire (AgNW) networks and a polyurethane (PU) protective layer onto a commercial textile, a machine‐washable EMIST with excellent EMI shielding effectiveness (EMI SE) (63.9 dB @ 3.0 wt% AgNW) is demonstrated. Here, the EMIST has several key advantages, which include the following: 1) remarkable washing durability (89% EMI SE retention after 20 machine‐washing cycles), 2) outstanding long‐term mechanical reliability, remaining stable under various deformation conditions (e.g., EMI SE retention of at least 82% after 5000 stretching cycles), and 3) excellent chemical stability. The research provides a high‐quality, affordable, and fully wearable EMIST that can protect engineers, soldiers, and civilians who work with, live near, or pass by electromagnetic or radioactive sources. A machine‐washable electromagnetic interference (EMI) shielding textile with excellent EMI shielding effectiveness (63.9 dB @ 3.0 wt% AgNW) is realized by designing silver nanowire (AgNW) networks and a polyurethane (PU) protective layer onto a commercial textile. The EMI shielding textile shows highly reliable EMI shielding even after 20 machine‐washing cycles and thousands of stretching‐release cycles. [ABSTRACT FROM AUTHOR]

Designing lightweight polyimide (PI) foam with low density, high heat resistance, excellent electromagnetic interference (EMI) shielding ability and good compressibility is urgent in practical application of aeronautics and aerospace. However, to guarantee high EMI shielding effectiveness (EMI SE), high conductive filler content was always required, which would lead to high stiffness and poor compressibility of the composite foam, because of the agglomerations and the limitation of the interaction force between conductive filler and PI matrix. Herein, desirable CNT dispersion could be achieved with the assistant of the functional group on graphene oxide surface and the "π-π" conjugation between graphene and CNT. The resultant composite foam exhibits an average EMI SE of 28.2 dB and specific EMI SE (SSE) of 7050 dB cm2 g−1 at an only 0.02 g cm−3 density. Meanwhile, the multi-layer structure formed in cell wall and chemical bonding between PI matrix and graphene flakes endow the composite foam with good cycling compression stability. Moreover, the high decomposition temperature (T d , 10%) of 630.9 °C exhibits great competition with other previously reported PI-based composites. These features confirm the potential of the CNT/graphene/PI foam as a lightweight, compressive, heat-resistant material for efficient EMI shielding and electromagnetic wave absorption. [Display omitted] • A facile approach for developing lightweight polyimide foam with uniform dispersion of carbon nanotube was designed. • Desirable dispersibility of carbon nanotube in polyimide matrices was achieved with the aid of graphene oxide. • The as-prepared polyimide foam exhibits excellent electromagnetic wave shielding ability and good compressibility. [ABSTRACT FROM AUTHOR]

In this work, we propose novel layer-structured polymer composites (PCs) for manipulating the electromagnetic (EM) wave transport, which holds unique electromagnetic interference (EMI) shielding features. The as-prepared PCs with a multilayered structure exhibits significant improvement in overall EMI shielding effectiveness (EMI SE) by adjusting the contents and distribution of electrical and magnetic loss fillers. The layer-structured PCs with low nanofiller content (5 wt % graphene nanosheets (GNSs) and 15 wt % Fe3O4) and a thickness of only 2 mm exhibited ultrahigh electrical conductivity and excellent EMI SE, reaching up to 2000 S/m and 45.7 dB in the X-band, respectively. The increased EMI SE of the layer-structured PCs was mainly based on the improved absorption rather than the reflection of electromagnetic waves, which was attributed to the "absorb-reflect-reabsorb" process for the incident electromagnetic waves. This work may provide a simple and effective approach to achieve new EMI shielding materials, especially for absorption-dominated EMI shielding. [ABSTRACT FROM AUTHOR]

Graphical abstract We fabricate the ultrathin and flexible four corners needle zinc oxide whiskers/silver/waterborne polyurethane (T-ZnO/Ag/WPU) conductive films to satisfy different EMI shielding demand by tuning the shielding network structure. Highlights • The specially designed 3D T-ZnO/Ag nanofiller is synthesized successfully. • The ultrathin and flexible T-ZnO/Ag/WPU EMI shielding film is fabricated. • The film with uniform structure shows an EMI SE of 42 dB at thickness of 0.02 mm. • The film with deposited layer structure exhibits an ultra-high EMI SE of 87 dB. Abstract With recent emergence of portable and wearable electronics, it is imperative to design a novel electromagnetic interference (EMI) shielding material which possesses flexibility, ultra-thinness and excellent EMI shielding effectiveness (SE) to prevent the adverse effect of electromagnetic radiation. Herein, we fabricate the ultrathin and flexible four corners needle zinc oxide whiskers/silver/waterborne polyurethane (T-ZnO/Ag/WPU) conductive films to realize different EMI shielding demand by tuning the nanofiller dispersion morphology. The T-ZnO/Ag/WPU composite film with uniform structure (prepared by blade coating method) shows excellent flexibility and EMI SE of over 42 dB at a thickness of only 0.02 mm. Highly reliable shielding ability is achieved with 92% EMI SE retention after 1000 folding cycle tests. The T-ZnO/Ag/WPU composite film with deposited layer structure (prepared by casting method) exhibits an ultrahigh EMI SE of over 87 dB at a thickness of 0.25 mm. At the same time, the T-ZnO/Ag/WPU composite shows great potential in printable circuit. The ultrathin and flexible T-ZnO/Ag/WPU composite films with excellent EMI SE are highly promising for applications in next-generation flexible electronics, especially the portable and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Conductive polymer composite with segregated structure has been well demonstrated to achieve high electromagnetic interference shielding effectiveness (EMI SE) due to the selectively distributed electrical nanofillers to establish desirable conductive networks. Nevertheless, the formation of segregated structure in low-melt-viscosity semi-crystalline polymer is still challenged and the segregated composite always suffers poor mechanical performance. Herein, elevated pressure and temperature were utilized to make a typical semi-crystalline polymer, polypropylene (PP), hold solid phase to restrict the diffusion of carbon nanotube (CNT) into its interior. Segregated CNT networks were facilely constructed in the resultant CNT/PP composite and imparted it with a superior EMI SE of 48.3 dB at 2.2 mm thickness and 5.0 wt% CNT loading, the highest EMI shielding level among the reported CNT/polymer composites at equivalent material thickness and CNT loading. Moreover, the elevated pressure and temperature effect dramatically increase the compressive, tensile, and flexural strength (modulus) of the CNT/PP composite by 133% (65%), 74% (130%) and 53% (50%), respectively, in comparison to those for conventional segregated CNT/PP composite, really overcoming the major mechanical shortcoming in the development of segregated composites for EMI shielding. Our work provides a facile strategy to fabricate the efficient EMI shielding and robust material with the construction of typical segregated structure in low-melt-viscosity semi-crystalline polymers. [ABSTRACT FROM AUTHOR]

Low-cost flexible EMI shielding materials have great market potential due to the rapid development of flexible electronics such as wearable health monitoring systems, flexible displays, and flexible power supply systems. Here, by fully exploiting its three-dimensional (3D) cross-linked structure, the ground tire rubber (GTR) in industrial waste was converted into a valuable and high-performance electromagnetic interference (EMI) shielding material. A carbon nanotube (CNT)/GTR composite with typical segregated structure was designed, with CNTs selectively localized at the boundaries of GTR domains. The composite containing only 5.0 wt% CNT exhibits a high electrical conductivity of 109.3 S/m and an EMI shielding effectiveness (SE) of 66.9 dB, superior to most of the reported CNT/polymer composites. Additionally, the CNT/GTR composite shows excellent flexibility and stability with 93% retention of EMI SE even after repeatedly bending to the radius of 2.0 mm for 5000 times. Our flexible EMI shielding material will benefit the fast-growing next-generation flexible electronic devices by providing low cost and reliable protection. [ABSTRACT FROM AUTHOR]

As a result of the characteristic of lightweight, outstanding chemical stability and corrosion resistance, carbon-based aerogels and foams have made great progress in electromagnetic protection. In this paper, the latest research progress in carbon-based aerogels and foams for electromagnetic interference (EMI) shielding is summarized and analyzed, including the mechanisms of different carbon nanostructures and the factors of electrical conductivity and dielectric properties, magnetic property, density, thickness and structural morphology on the EMI shielding performance of the carbon-based materials. In the end, the development trend and future prospect of carbon-based aerogels/foams are also outlined. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of structure-function integrated materials is an important trend in military field. How to achieve the enhanced interfacial property and electromagnetic interference (EMI) shielding property of carbon fiber (CF) reinforced polymer (CFRP) simultaneously is the main challenge at present. Herein, the mechanically strengthened CFRP with superior EMI shielding property was developed by the introduction of reduced graphene oxide/Fe 3 O 4 , i.e. , RGF into epoxy resin, combined with CF modified by uniform polyaniline (PANI) shell. The interlaminar shear analysis indicated that the RGF nanofiller in resin matrix and uniform PANI shell on CF could effectively optimize the interlaminar shear behavior due to the enhanced cohesive strength and adhesion strength among interface phase. Notably, the resultant composite achieved an interlaminar shear strength of 80.4 MPa, 37.4% higher than that of virgin CF/epoxy composite. Additionally, thanks to the excellent electromagnetic wave loss of RGF as well as the unique alternating multilayer, the super EMI shielding effectiveness of 78.5 dB with was achieved when the RGF content was 4.0 wt%, much higher than 34.7 dB of virgin CF/epoxy composite. The excellent interlaminar shear and EMI shielding behaviors endow the composite with potential application in military field, which providing a new strategy for the development of high-performance CF/epoxy composite. [Display omitted] • PANI and reduced graphene oxide/Fe 3 O 4 were introduced to improve the adhesion strength and cohesive strength of composite. • The carbon fiber/epoxy composite showed a superior electromagnetic interference shielding effectiveness of 78.5 dB. • The carbon fiber/epoxy composite exhibited excellent mechanical properties, with an interlaminar shear strength of 80.4 MPa. • An interfacial enhancement mechanism was proposed to explain the excellent interlaminar shear property of the composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • The flexural fibers endow the CCT with an intrinsic stretchability of 40% strain. • The CCT exhibits stable EMI SE of 51.7 dB even after 1000 cycles of 100 % strain. • The CCT keeps good air permeability, softness and lightness even after modifications. • The excellent superhydrophobicity enables the CCT to tackle complex environments. • The Joule heating imparts the CCT outstanding thermal management capability. Conductive composite textiles (CCTs) as multifunctional integrated platform provide an effective path for developing flexible electromagnetic interference (EMI) shielding composites. However, conventional CCTs suffer from EMI shielding performance failure or the loss of textile's intrinsic properties under large tensile strain. Hence, in this work, a stretchable EMI shielding CCT that retains the inherent attributes of textile is proposed via weft-knitting and in-situ chemical Ag deposition. The complete and continuous silver nanoparticles (AgNPs) conductive networks bring excellent conductivity (38560 S/m) and ultrahigh EMI shielding performance (80.1 dB) in unstretched state. When tensile strain is applied, the fibers are gradually straightened from flexural state within 40 % strain, and then begin to be stretched at bigger strains, which benefits from the weft-knitting structure. Therefore, the conductive networks on the fiber surfaces are well protected from damage in the initial 40 % strain range, resulting in a stable EMI shielding performance (51.7 dB) even after 1000 cycles of 100 % tensile strain. Crucially, the CCT preserves good air permeability, softness and lightness even though a series of modifications and tensile strains are applied. Other than the EMI shielding perforamnce, the excellent superhydrophobicity (the contact angle of 158°) imparts the textile with the capability to tackle complex environments easily. Moreover, the textile can readily be heated to 73.4 °C at a low voltage of 0.5 V, showing outstanding Joule heating performance. Even after a long period of heating (3600 s), the textile maintains superior thermal stability, indicating potential applications in wearable heaters. In brief, this multifunctional CCT has excellent comprehensive properties and is expected to further expand the applications of EMI shielding textiles. [ABSTRACT FROM AUTHOR]

Developing ultralight, highly conductive carbon aerogels with facilely tunable microscopic structure is still a long-standing issue to effectively shield the electromagnetic interference (EMI). Here, highly porous and conductive all biomass-derived carbon aerogels were first successfully achieved by carbonizing cellulose aerogels, which held excellent structure designability by controlling cellulose content in lithium hydroxide/urea aqueous solution, porogen composition in solvent exchange process, as well as freezing rate during freeze-drying. The as-prepared cellulose-derived carbon aerogels with optimized structure of small pore size and dense three-dimensional sheet-like skeleton network were demonstrated to be highly efficient to greatly prolong the propagation path of electromagnetic waves (EMWs) and dissipate incident EMWs into heat energy, exhibiting the dominant EMI shielding mechanism of EMW absorption. As a result, an impressive EMI shielding effectiveness of as high as 93.1 dB in the X band frequency range at a density of as low as 0.079 g cm−3 was achieved. Of more practical significance is that the new insight into the relationship between microscopic pore structure of carbon aerogels and their EMI shielding performance provides a valuable clue in developing highly efficient EMI shielding carbon aerogels in the application of microelectronics, aircraft and spacecraft. An all biomass-derived carbon aerogel with small pore size and dense three-dimensional sheet-like skeleton network exhibits a density of as low as 0.079 g cm−3 and an impressive EMI shielding effectiveness of as high as 93.1 dB with electromagnetic as the dominant electromagnetic interference shielding mechanism in the X band frequency range. Image 1 [ABSTRACT FROM AUTHOR]

• Segregated structure was firstly regulated in CNT/UHMWPE composites by the solid-phase stretching. • Selective electromagnetic interference shielding performance was obtained by the highly oriented segregated structure. • Mechanical performance was significantly enhanced by the formation of interfacial shish calabash and oriented crystals. Manipulation of the conductive network is essential for the electromagnetic interference (EMI) shielding performance of conductive polymer composites, which have broad application prospects to address the concerns of electromagnetic pollution emitted by modern electronics. In this work, the oriented segregated structure was achieved in carbon nanotube (CNT)/ultrahigh molecular weight polyethylene (UHMWPE) composites via solid-phase stretching and the orientation of segregated network was controlled by adopting different draw ratios. Benefiting from the unique oriented segregated structure, the composites delivered prominent EMI shielding performance with intriguing frequency selectivity, which did not occur in conventional segregated composites. Moreover, remarkable mechanical reinforcement was obtained in the oriented segregated composites, which was attributed to the interfacial crystallization along segregated pathways and the formation of highly oriented lamellae. At a draw ratio of 6, the oriented segregated composite with 2 wt% CNTs showed the maximum EMI shielding effectiveness of 33.5 dB and tensile strength of 216.1 MPa, which surpassed the conventional segregated composite by 69.2% and 455.5%, respectively. This effort demonstrates a simple, feasible, and effective approach for the design and fabrication of mechanically robust, bandwidth-selective EMI shielding composites. [ABSTRACT FROM AUTHOR]

[Display omitted] • In situ AgNPs deposition is used to construct homogeneous conductive networks. • The textile keeps so far the highest EMI SE of 94.1 dB at 100 % tensile strain. • Wrinkles endow the textile with multifunctionality apart from high EMI SE. • The textile keeps a stable EMI SE under chemical exposure and mechanical damage. The soaring growth of flexible electronic devices has boosted the demand for electromagnetic interference (EMI) shielding materials with excellent stretchability, stability and even breathability. However, it is still a challenge to develop conductive materials with outstanding stretchable EMI shielding performance. In this work, we developed a textile with porous wrinkled conductive network through in situ polydopamine-assisted deposition of silver nanoparticles (AgNPs) on wrinkled fiber mat and polydimethylsiloxane post modification. This unique wrinkled conductive networks endows the textile with excellent electrical conductivity (103700 S/m), good breathability, superhydrophobicity, and ultra-high stretchable EMI shielding properties. The EMI shielding effectiveness (EMI SE) of the textile reaches 101.1 dB in unstretched state and still maintains at 94.1 dB at 100 % tensile strain. The superhigh EMI SE under such a high strain is much higher than the previously reported results so far. Moreover, the textile shows exceptionally good cyclic tensile durability under 100 % stain. After 1000 tensile cycles with 100 % strain, the EMI SE of sample only drops by 3.8 %. This work provides a new path for developing stretchable high EMI shielding performance materials, which is of great significance to solve the EMI problems of emerging flexible and wearable electronic devices. [ABSTRACT FROM AUTHOR]

Lightweight and robust carbon nanotube (CNT)/chitosan (CS) foams were assembled by a facile unidirectional freeze-drying method in this work. The CNT/CS foam exhibited an excellent electromagnetic interference (EMI) shielding effectiveness (SE) of 37.6 dB while the density was only 17.6 mg·cm −3 , and thus the corresponding specific SE was up to 8556 dB·cm 2 ·g −1 . The superior EMI shielding performance was mainly attributed to the perfect conductive networks. Additionally, the absorption coefficient of CNT/CS foam was up to 81.73% under high EMI SE of 37.6 dB, which was remarkable among the reported EMI shielding materials with comparable EMI shielding level. More importantly, the addition of CS significantly increased the compressive strength and modulus of CNT/CS foam to 34.1 KPa and 177.1 KPa, which were 84% and 149% higher than those for the pure CNT foam, respectively. These results indicate that the CNT/CS foam is an ideal high-efficient EMI shielding material, which has high potential applications in the fields of aerospace, automotive, and electronic devices. [ABSTRACT FROM AUTHOR]

Abstract Conductive polymer composites (CPCs) with segregated structure exhibit outstanding electromagnetic interference (EMI) shielding performance at low filler loadings. However, the mechanical performance is compromised due to poor interfacial adhesion resulting from the selective distribution of conductive fillers. Herein, a simple and effective approach, i.e. solid-phase extrusion (SPE), was proposed to fabricate segregated carbon nanotube (CNT)/poly(vinylidene fluoride) composites with high mechanical performance. Morphology examination revealed that both the matrix and segregated conductive network were highly oriented along the extrusion direction under the forceful flow field of SPE. The resultant SPE composites showed an excellent electrical conductivity of 74.5 S/m and a high EMI shielding effectiveness of 36.8 dB with only 4 wt% CNTs. More notably, simultaneous enhancement of the strength and fracture toughness was achieved. Compared to the counterparts with conventional segregated structure, tensile strength and elongation at break of SPE composites were significantly increased by ∼100% and ∼900%, reaching 120–140 MPa and 60%, respectively. This work demonstrates a valuable approach to prepare high-performance CPCs for EMI shielding applications. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

A flexible and highly conductive nylon porous membrane (NPM)/nickel (Ni) composite film with outstanding electromagnetic interference (EMI) shielding performance is fabricated via a facile electroless deposition method. The NPM, with a large specific surface area, is amenable to the electroless deposition of Ni and the enhancement of interaction between Ni and NPM. Highly conductive Ni layers are uniformly deposited on the upper and lower surfaces of NPM to construct a sandwich structure that provides numerous interfaces to reflect, scatter, and absorb electromagnetic waves. The resultant NPM/Ni film exhibits an ultra-high EMI shielding effectiveness (EMI SE) of 77 dB with a film thickness of only 100 μm. Moreover, the NPM/Ni film shows cyclic EMI shielding stability under repeated mechanical deformation, with 85% retention after 300 bending cycles. Our work provides an effective approach to fabricate reliable metal-polymer composite films that show potential for applications in EMI shielding. [ABSTRACT FROM AUTHOR]

Polymer composites embedded with high filler loads (≥50 wt%) are urgently needed to address the electromagnetic interference (EMI) shielding and thermal barrier problems for the high-power integrated electronic devices. However, designing polymer composites with high filler loads remains a challenge due to difficulties in processability and poor flexibility. Herein, high graphene nanoplates-loaded polyurethane (GNP/PU) composites were enabled by a tractable and scalable polymer-infiltrated technique, in which GNPs were in compact contact face to face and arranged along the in-plane direction. The formation of such structure provided good channels for the transmission of electrons and phonons in the GNP/PU composites. Impressively, the GNP/PU composites showed strong EMI shielding and thermal conductivity, with a superior EMI shielding effectiveness of 67.6 dB (0.4 mm thickness), and extremely high thermal conductivity of 41.60 W/(m·K). Moreover, the GNP/PU composites were proven to have excellent mechanical flexibility, EMI shielding stability, and thermal management capability. With good comprehensive performance and high processability, the GNP/PU composites hold great promise for EMI shielding and thermal management applications in the field of highly integrated electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

Inserting aramid fiber (AF) fabric is an effective strategy to improve the impact resistance of carbon fiber reinforced polymer composite (CFRP) when it was used as a material integrated with electromagnetic interference (EMI) shielding and structural functions. Unfortunately, due to the smooth and inert surface of AF, achieving the desirable heterogeneous interface on the surface of AF fabric to simultaneously improve the impact resistance and EMI shielding of CFRP remains a challenge. In this work, a mechanically reinforced carbon fiber (CF)/epoxy composite with efficient EMI shielding effectiveness (SE) was developed via intercalating aramid fiber (AF), which is modified through the "flexible-rigid" structure formed by carbon nanotube (CNT) and polyacrylic acid (PAA). Due to the impressive roughness and wettability of the modified AF, the impact strength of the resultant CF/AF/epoxy composite can reach 80.3 KJ/m2, which is 20.6 % higher than that of the composites without modification. Additionally, thanks to the excellent electromagnetic wave loss of "flexible-rigid" heterogeneous interface as well as the unique Jaumann-like structure, the composites also exhibit an efficient EMI shielding effectiveness of 34.4 dB. The desirable impact strength and efficient EMI shielding performance endow the resultant CFRP with a great application potential in electromagnetic protection field. [Display omitted] • Aramid fiber (AF) was introduced by intercalation toughening to improve the impact resistance of composites. • AF was modified with the "flexible-rigid" structure of PAA/CNT to enhance the interfacial interaction. • The carbon fiber/epoxy composites exhibited excellent mechanical properties, with an impact strength of 80.3 KJ/m2. • The composites showed an excellent electromagnetic shielding effectiveness of 34.3 dB that can meet commercial requirements. [ABSTRACT FROM AUTHOR]

The formation of segregated structure in conductive polymer composite is an effective strategy to improve electromagnetic interference (EMI) shielding performance. However, inferior mechanical properties always existed in the segregated composite due to weak interfacial adherence or defects. Herein, an interface-reinforced segregated structure was constructed in a carbon nanotube (CNT)/polydimethylsiloxane (PDMS) composite by creating chemical bonds between PDMS microcells and the continuous PDMS interfacial phase embedded with CNT. The interface-reinforced segregated composites achieved the integration of excellent EMI shielding and good mechanical properties. Specifically, the resultant composite exhibited a superior EMI shielding effectiveness (EMI SE) of 47.0 dB at only 2.2 vol% CNT content. The tensile strength and elongation at break of the composite were 3.6 MPa and 87.0%, increased by 35.0 and 7.0 times in comparison to the conventional segregated composite. The interface-reinforced segregated composite also demonstrated excellent reliability with high EMI SE retention of 80% even after suffering from 1000 stretching-releasing cycles at a terminal strain of 30%. This work provides an important guideline for the development of high-performance polymer composite with efficient EMI shielding and good mechanical performances. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A flexible EMI shielding film is fabricated with electroless Ag plating assisted by PDA adoption and Sn2+ activation. • The films exhibit continuous coating of Ag nanolayer and perfect electrical conductivity of up to 168,060 S/m. • Ultrahigh EMI SE of up to 91.6 dB is obtained with only 1.38 vol% of Ag loading and 100 μm thickness. • Impressive EMI SE enhancement per unit filler and thickness (4078 dB/vol%/mm and 240.9 dB/wt%/mm) is achieved. • The film also have excellent mechanical flexibility, tensile property, water-proof, breathable and antibacterial ability. The explosive development of flexible precision electronic devices necessitates materials with ultrahigh electromagnetic interference shielding effectiveness (EMI SE) and excellent mechanical flexibility to suppress unnecessary electromagnetic radiation. Herein, we report a feasible strategy to fabricate a flexible and water-proof porous film for high-efficiency EMI shielding, by utilizing electroless plating of silver (Ag) with the assistance of polydopamine (PDA) and Sn2+ on a commercial nylon mesh (CNM), followed by razor-thin polydimethylsiloxane (PDMS) coating. Results indicate that the fabricated CNM/PDA/Ag/PDMS (CNMAAS) films exhibit continuous coating of Ag nanolayer, which imparts the films perfect electrical conductivity up to 168,060 S/m and ultrahigh EMI SE of up to 91.6 dB, with only 1.38 vol% of Ag loading and 100 μm thickness. The films also exhibit impressive EMI SE enhancement per unit filler and thickness (eg: 4078 dB/vol%/mm and 240.9 dB/wt%/mm for the CNMAAS2 film), owing to the increased interfacial polarization and the conduction loss. Outstanding EMI SE reliability is also achieved for the films, with retentions as high as 96% even suffering 5000 cycles of bending deformation, ascribing to the good mechanical flexibility of porous CNMAAS films. Finally, water-proof, breathable and antibacterial ability of the CNMAAS film were demonstrated. This work provides a facile approach to effectively design and fabricate conductive nanolayers for ultrahigh-performance EMI shielding materials that can be applied in flexible smart electronic devices. [ABSTRACT FROM AUTHOR]

In this work, a novel self-writing visible light processing method is employed to fabricate self-propagating polymer waveguide based porous epoxy matrix, which subsequently turns into micro-truss structured carbon nanotube (CNT)/epoxy conductive composites through CNT dip-coating. It is discovered that, by illuminating a photosensitive epoxy pre-polymer with intersecting blue LED beams simultaneously for only 15 min, 3D micro-truss structured epoxy matrix with thickness of ∼1.8 mm is obtained. When incorporating CNTs with a low content of 1.20 vol%, the micro-truss structured CNT/epoxy composites exhibit high electrical conductivity of 62.93 S/m. These composites show absorption-dominated shielding mechanism, and high electromagnetic interference (EMI) shielding efficiency (SE) of 34.5 dB is obtained in the X band with 1.20 vol% of CNT. The specific shielding efficiency (SSE) of the CNT/epoxy composites is up to 100 dB cm3 g−1, and the corresponding SSE/t eliminating the effect of thickness is up to 535 dB cm2 g−1, which is much higher than that reported in other studies with the same CNT contents. This work provides a quick and scalable technique to prepare polymer matrix with ordered porous structures, and would also inspire and guide the fabrication of well-ordered porous conductive polymer composites with superior EMI shielding performances. [Display omitted] [ABSTRACT FROM AUTHOR]

To ensure the normal operation of electronic equipment, electromagnetic interference (EMI) shielding materials are required to mitigate interference from electromagnetic waves (EMWs), whereas, the development of EMI shielding materials with ultra-high EMI shielding effectiveness (EMI SE), excellent flexibility and satisfactory stability under mechanical deformation is still a challenge. In this paper, we constructed a three-dimensional (3D) Ag microfiber sponge (AgMS) with high conductivity and low density using the blow spinning method. We manufactured an AgMS/polydimethylsiloxane (PDMS) composite with extremely high EMI SE and superb flexibility by backfilling PDMS into the AgMS. The EMI SE of the AgMS/PDMS composite can reach 100.4 dB with a thickness of 0.5 mm and an AgMS content of 3.6 vol%. Besides, the AgMS/PDMS composite possesses outstanding mechanical reliability, remaining stable under various deformation conditions. The EMI SE can retain 91% of its initial value after 1600 stretching cycles, 84% after 1600 bending cycles, and 93.5 dB after 1600 compression cycles. Furthermore, the AgMS/PDMS composite also has excellent compression-resilience properties and chemical stability. These key properties suggest that the AgMS/PDMS composite demonstrates great potential for EMI shielding gaskets in the commercial, medical, and aerospace fields. [Display omitted] [ABSTRACT FROM AUTHOR]

• A self-standing liquid metal-based film was prepared for EMI shielding. • The resultant liquid metal-based film achieved a remarkable electrical conductivity of 7752 S/cm. • The EMI SE of the liquid metal-based film could reach 78.2 dB at a tiny thickness of 20 μm. • The liquid metal-based film possessed excellent reliability and superior thermostability. Liquid metals (LM) have a high potential for Electromagnetic interference (EMI) shielding application, due to their soft feature and excellent electrical conductivity. However, it still remains a huge challenge to fabricate a self-standing LM film for EMI shielding, due to the liquid feature of LM. Herein, we designed a self-standing LM-based film by incorporating minute quantities of aramid nanofiber (ANF) to construct a supporting framework via vacuum filtration. Due to the formation of highly conductive LM networks, the resulting LM/ANF film achieved a remarkable electrical conductivity of 7752 S/cm. The promising electrical conductivity endowed the LM/ANF film with an extremely high EMI shielding effectiveness (EMI SE) of 78.2 dB at a mere 20 μm thickness. The LM/ANF film also possessed excellent reliability and superior thermostability, without an obvious decline in the EMI SEs after 5000 folding cycles and thermal treatment (250 °C) for 20 h, respectively. This study offers a novel design strategy to develop ultrathin EMI shielding films combined with high reliability and thermostability for application in modern high-power electronic devices. [ABSTRACT FROM AUTHOR]

Increasingly serious electromagnetic radiation pollution puts forward higher demands on wearable fabrics: high electromagnetic interference (EMI) shielding effectiveness. Besides, the ability for the fabrics to keep the human body warm is also important in a frigid environment. However, there have been few reports on fabrics simultaneously with the two functions so far. Here, a flexible wearable fabric with both excellent EMI shielding and passive radiation heating functions was developed through integrating silver nanowire (AgNW), ferroferric oxide (Fe 3 O 4) nanoparticles, and polydimethylsiloxane (PDMS) onto a commercial fabric. The conductive AgNW networks endowed the fabric with a super-high EMI shielding property of 100.9 dB at the thickness of 450 μm – one noticeable advantage. The passive radiation heating ability was achieved by regulating the spectral selectivity of the fabric (a high solar energy absorptivity of 80.5% at 250–2500 nm, a low mid-infrared emissivity of 0.21 at 7 − 14 μm), so no electric power is needed for the fabric to heat the human body – another prominent advantage. The fabric resulted in a 20.6 °C temperature enhancement of the simulated skin under sunlight in the daytime and a 6.4 °C temperature enhancement in nighttime compared with traditional cotton fabric with the same thickness. Thus, the prepared multifunctional fabric can effectively protect the human body from electromagnetic radiation harm and injury caused by cold climate. This work holds great potential to enlarge the application scope of current EMI shielding fabrics. [Display omitted] • A flexible wearable fabric with both excellent EMI shielding and passive radiation heating functions was prepared. • The fabric possesses a super-high EMI shielding property of 100.9 dB at the thickness of 450 μm. • Warmed the simulated skin by 20.6/6.4 °C in daytime/nighttime environments compared to pristine cotton fabric. • The fabric can protect the human body from electromagnetic radiation and cold environment harm at the same time. [ABSTRACT FROM AUTHOR]

Construction of segregated structures within conductive polymer composites (CPCs) is a prospective strategy to enhance electromagnetic interference (EMI) shielding effectiveness (SE). However, the CPCs of segregated structures frequently experience worsened mechanical performances due to weak interface reactions between adjacent polymer domains, which are hindered by conductive fillers. Herein, 3D-printed segregated carbon nanotube (CNT)/polylactic acid (PLA) composite was firstly exploited to develop high mechanical properties while achieving good performance for electromagnetic interference shielding. Within the final 3D-printed CNT/PLA composite, CNTs coated on 3D-printed PLA scaffold were translated to interconnected conductive network after compression. Thus, EMI SE of composite was as high as 67.0 dB when 5.0 wt% CNTs were loaded. Furthermore, 3D-printed PLA scaffold with a highly continuous structure also benefited the mechanical robustness of the segregated composite, revealing the bending strength (87.8 MPa) and Young's modulus (4.43 GPa), which were 101% and 43% higher than 43.7 MPa and 3.08 GPa for the conventional CNT/PLA composite. Moreover, the regulation of 3D-printed PLA scaffolds results in promising CNT/PLA composites with tunable EMI SE. This work suggests that 3D printing technology is an effective and easy approach to develop the outperformance of CPCs for different radiation source fields and electronic devices. Unlabelled Image • 3D-printing technology was exploited to construct segregated conductive polymer composites for electromagnetic interference shielding. • The segregated structures endow high mechanical properties and good performance of electromagnetic interference shielding. • Electromagnetic interference shielding effectiveness is tunable by controlling the 3D-printed polylactic acid scaffolds. [ABSTRACT FROM AUTHOR]

The development of high electromagnetic interference (EMI) shielding composites is significant to practical application of electronic equipment. Nevertheless, there still remains a challenge in achieving durable EMI shielding effectiveness (EMI SE) when the EMI shielding materials suffers external mechanical damage or other diverse harsh circumstances. Herein, a healable EMI shielding composite was facilely developed, with dynamic crosslinking polyurethane holding Diels–Alder bonds (PUDA) as substrate and carbon nanotube (CNT) as electrical fillers. Segregated conductive networks with CNT selectively distributed among the interfaces of PUDA regions were constructed, endowing the CNT@PUDA composite with high EMI SE of 41.2 dB (X-band) at 7.0 wt% CNT loading. Thanks to the reversible Diels–Alder reaction, the CNT@PUDA composites can be repaired effectively and repetitively by heating or subjecting DC electricity. The EMI SE of cracked composite with 5.0 wt% CNT can recover from 17.1 to 33.8 dB (96% retention in comparison to original 35.5 dB) even after repeated cutting/healing process for three times, thanks to the reconstructed segregated CNT networks with the help of healable PUDA domains. The splendid mechanical properties with high healing efficiency of 91% further ensure the reliable EMI SE. The construction of DA dynamic bonds and segregated conductive network in our study offers meaningful guidance to practical construction and development of healable EMI shielding facility. Image 1 [ABSTRACT FROM AUTHOR]

The formation of segregated structure in conductive polymer composites reveals great superiority in gaining improved electromagnetic interference (EMI) shielding performance. Nevertheless, the restricted processing method and seriously deteriorated mechanical properties hamper the practical applications of such segregated composites. Herein, we demonstrate simultaneously improved EMI shielding and mechanical performance in a segregated carbon nanotube/polypropylene (CNT/PP) composite, via a facile and eco-friendly method composed by pre-coating, melt mixing, and injection molding. The segregated CNT/PP composite containing only 3.5 wt% CNT exhibits an average EMI shielding effectiveness (EMI SE) of 32 dB, which shows 130% and 30% improvements in comparison to 14 dB for the CNT/PP composite prepared by conventionally injection molding and 25 dB for the CNT/PP composite prepared by compression molding. Our segregated CNT/PP composite also attains a high elongation at break (EB) of 78%, about 4 and 17 times higher than 16% for the conventionally injection molded one and 4% for the compression molded one, with comparable tensile strength and Young's modulus. This work provides a feasible approach to guide the scaled preparation of segregated composites with satisfactory EMI shielding and mechanical performance. Image 1 • An eco-friendly injection molding method was demonstrated to develop segregated CPC for EMI shielding. • An outstanding elongation at break was achieved. • Favorable expansibility and large-scale production capacity can be implemented. [ABSTRACT FROM AUTHOR]

Electromagnetic interference (EMI) shielding composites are inevitably damaged in the long-term usage which would affect the regular operation of the devices. Hence, the demand for materials with healable and reliable EMI shielding performance has increased. Here, a flexible conductive composite owning both self–healing and EMI shielding functions is facilely developed, with carbon nanotubes (CNTs) as conductive filler and dynamically crosslinked polyurethane bearing Diels–Alder bonds (PUDA) as polymer matrix. The PUDA/CNT composite shows a high EMI shielding effectiveness (EMI SE) of 30.7 dB at 5.0 wt% CNT loading in the range of X-band (8.2–12.4 GHz). And the EMI SE can recover from 16.8 dB for damaged state to 29.8 dB after three times cut/healing cycles, revealing excellent EMI SE retention of 97.1%. The PUDA/CNT composite also exhibits healable tensile properties with an elongation at break up to 571% ± 31% at 2.0 wt% CNT content and self-healing efficiency of 89.2% after the repeatable healing. This work demonstrates a healable EMI shielding composite, which ensures the reliability and long-time use under harsh conditions. Image 1 • The flexible self–healing EMI shielding composite is facilely developed. • The composite exhibits excellent mechanical and EMI shielding properties. • The composite shows highly efficient self-healing performance based on the Diels-Alder bonds. [ABSTRACT FROM AUTHOR]

• An eco-friendly conductive ink was prepared for EMI shielding. • The electrical conductivity of the EMI shielding coating could reach 14,300 S cm−1. • An ultrahigh EMI SE of 74.5 dB was achieved for the EMI shielding coating. • The EMI shielding coating exhibited sufficient EMI shielding reliability. Conductive inks are applied widely in electromagnetic interference (EMI) shielding coating, but the heavy use of organic solvents may cause safety issues and environment pollution. We demonstrated the preparation of an eco-friendly conductive ink that is composed of silver flakes, waterborne polyurethane, and fluorocarbon surfactant (Capstone FS-30), with deionized water as solvent. The conductive ink can be drop-deposited easily on polyethylene terephthalate film to develop a highly efficient EMI shielding coating that achieves an ultrahigh EMI shielding effectiveness (EMI SE) of 74.5 dB at only 10 μm thickness. The shielding coating exhibits sufficient flexibility to ensure an EMI SE retention up to 96%, even after 5000 bending–releasing cycles (bending radius of 2 mm), which reveals an excellent EMI shielding reliability. The shielding coating also possesses a mechanical fastness under ultrasonic treatment and a chemical durability to various organic solvents. These impressive characteristics make our conductive ink attractive for effective electromagnetic protection, especially in high integrated equipment and devices. [ABSTRACT FROM AUTHOR]