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With the advent of the 5G era, electromagnetic pollution has become increasingly severe. Developing high-performance electromagnetic shielding materials that are flexible and possess excellent mechanical properties is an ideal choice for modern integrated electronic devices and microwave protection, particularly for low-frequency electromagnetic waves. Herein, single-layer and double-layer composite fabrics coated with Barium ferrite (BaFe 12 O 19) and Graphene oxide (GO) were prepared using a coating strategy to achieve high shielding and wave absorption capabilities in the low-frequency band. The layered structure of BaFe 12 O 19 and GO enhances interface loss for reflecting and absorbing microwaves. The double-layer coated composite fabric, with GO as the surface coating material and BaFe 12 O 19 as the bottom coating material, achieved a shielding efficiency (SE) of 66.57 dB with a thickness of only 1.1 mm. Additionally, the minimum reflection loss (RL) reached −11.41 dB at 1.33 GHz, demonstrating exceptional electromagnetic protection at low frequencies. Moreover, the GO-BaFe 12 O 19 coated composite fabric exhibited excellent UV resistance, mechanical stability, and infrared stealth protection. The material holds significant implications in the field of electromagnetic protection, especially for personal protective equipment and equipment protection. • Single-layer and double-layer composite fabrics coated with BaFe 12 O 19 and GO were prepared using a coating strategy to achieve high shielding and wave absorption capabilities in 0.01∼3 GHz. • The double-layer structure of BaFe 12 O 19 coating and GO coating enhances interface loss for reflecting and absorbing microwaves. • The uniform conductive network of the conductive fabric helps to reflect the waves. • The SE of the GO-BaFe 12 O 19 coated composite fabric can reach 66.57 dB at 2.9 GHz, and the RL can reach -11.41 dB at 1.33 GHz. • The composite fabric also has good mechanical firmness, flexibility, and anti-ultraviolet properties, which is of great significance in the field of electromagnetic protection. [ABSTRACT FROM AUTHOR]

In this project, polyaniline powder was firstly prepared by in situ polymerization using aniline as the monomer, ammonium persulfate as the oxidant, and camphor sulfonic acid as the dopant. Next, polyester-cotton fabrics were used as the base fabrics, polyaniline, cobalt ferrite, and carbon fiber powder as the functional particles, and PU-2540 type polyurethane as the base, and single-layer coated polyester-cotton fabrics were prepared by the textile coating process. Finally, the effects of the polyaniline, cobalt ferrite, and carbon fiber powder doping ratio and functional particle content on the shielding effectiveness, reflection loss, real and imaginary parts of the dielectric constant, and loss angle tangent of single-layer coated polyester-cotton fabrics were focused on using the controlled variable method. The results show that in the frequency range of 0.01–3 GHz, when the doping ratio of polyaniline, cobalt ferrite, and carbon fiber powder is 1:0:3, and when the content of functional particles is 40%, the minimum reflection loss of single-layer coated polyester-cotton fabrics is –22.1 dB at 1.6 GHz, and the effective absorption bandwidth is 1.14 GHz. [ABSTRACT FROM AUTHOR]

The double-layer coated basalt fiber fabric was prepared using polyurethane as the matrix and adopting a coating technology on the basalt fiber fabric. Firstly, the influence of two types of functional particles, graphite and graphene, on the dielectric properties (the real and imaginary parts and the loss tangent value), shielding effectiveness and mechanical properties of the double-layer coated basalt fiber fabric was analyzed. Then, the double-layer coated basalt fiber fabric of two types of structures, graphite/fabric/graphite and graphene/fabric/graphite, were prepared. Secondly, the influence of the contents of graphite and graphene on the electromagnetic properties and mechanical properties of the double-layer coated basalt fiber fabric using the method of controlling variables was studied. The results showed that the polarizing ability, the loss ability, the attenuating ability and the shielding ability of the double-layer coated basalt fiber fabric for the graphene coating were all superior to those of the graphite coating. Within the range of 0–1100 MHz, when the graphite content was 20%, the polarizing ability, the loss ability and the attenuating ability of the double-layer fabric were the strongest. When the graphene content was 20%, the polarizing ability to electromagnetic waves of the double-layer fabric was the strongest; when the graphene content was 15%, both the loss ability and attenuating ability to electromagnetic waves of the double-layer fabric were the strongest; and when the graphene content was 5%, the shielding ability to electromagnetic waves of the double-layer fabric was the strongest. When the graphite content was 20% and the graphene content was 10%, the displacement was within the range of 0–4.7 mm, and the load was 3411.1 N. [ABSTRACT FROM AUTHOR]

The single-layer coated fabric was prepared using the polyurethane and the coating technology on the nylon. The influence of the wave-absorbing functional particles (graphene, graphite, hydroxy nickel powders, micron iron powders, silver-coated copper powders, silver-coated hollow glass beads) on the electromagnetic properties and the mechanical properties of coated fabrics was explored. Results showed that within the frequency range of 0 MHz∼1000 MHz, when the ratio of contents of the graphite as the wave-absorbing functional particle and the graphene was 1:1, the real and imaginary parts and the loss tangent of the dielectric constant of the graphene single-layer coated fabric were all the largest, namely the material's polarizing ability, the loss ability and the attenuation ability to electromagnetic waves were all the strongest; within the frequency range of 0 MHz∼40 MHz, when the ratio of contents of the micron iron powder as the wave-absorbing functional particle and the graphene was 1:1, the shielding effectiveness of graphene single-layer coated fabric was the largest, the shielding ability to electromagnetic waves was the the strongest. [ABSTRACT FROM AUTHOR]

The coated composite was prepared by using the graphite and silver-coated copper powders as functional filler and adopting the coating-finishing method on the continuous basalt fiber fabric. The influence of the proportion of functional fillers in the coating on the dielectric properties, wave-absorbing properties, shielding properties and conductive properties of the coated composite was studied, in the meanwhile, tensile strength of the coated composite was tested, and tensile properties was studied. Results showed that the basalt fabric with a pure graphite coating had the largest value of the real and imaginary parts of the dielectric constant in the frequency band of 0.08 ∼ 1.0 GHz. And when the sample with a matching ratio of the graphite and silver-coated copper powder of 2:8 was in the frequency band of 1.5 ∼ 1.7 GHz, its reflection loss was larger than −10 dB. For the continuous basalt fabric coated with the pure silver-coated copper powders, the shielding efficiency (SE) was larger than 20 dB and it had a good shielding effect. [ABSTRACT FROM AUTHOR]

In this experiment, the polyaniline coated fabrics were produced using aniline as the monomer by in-situ polymerization, p-toluenesulfonic acid as the doping agent and ammonium persulfate as the oxidant on the polyester fabric. The influence of different process conditions on the dielectric properties of the polyaniline coated fabric was explored. The fastness to rubbing of the coated fabrics was tested. The results show that the concentration of aniline and the oxidant both influence the dielectric properties of the fabrics. An appropriate aniline concentration is beneficial to increase the output of the polyaniline and reduce sudden and violent polymerization. A suitable oxidant concentration is beneficial to form polyaniline with a complete structure, reducing the occurrence of peroxide. When the aniline concentration was 0.4 mol/L and the oxidant concentration was 0.4 ∼ 0.5 mol/L, the polarizing ability, loss ability and absorbing-attenuation ability of the fabrics to electromagnetic waves are all stronger. The dielectric properties of the obtained polyaniline coated fabrics varied corresponding to different types of dopants and doping levels. Compared to glacial acetic acid, hydrochloric acid and nitric acid, the dielectric properties of the prepared coated fabric were optimal when using p-toluenesulfonic acid as the dopant. When the concentration of the p-toluenesulfonic acid was 0.2 mol/L, the polarizing, loss and absorbing-attenuation abilities of the fabrics to electromagnetic waves are all stronger. [ABSTRACT FROM AUTHOR]

Three-layer coated composites with good electromagnetic properties were prepared on a plain polyester–cotton blended fabric with PU2540 polyurethane resin as a matrix; graphene, graphite and bismuth oxide were used as coating functional particles; and the influences of types of surface-layer functional particles, middle-layer functional particles and bottom-layer functional particles on electromagnetic properties of three-layer composites were explored. Results showed that when graphite, graphene and graphene were respectively used as bottom-layer, middle-layer and surface-layer functional particles, within the range of 1–1000 MHz, the polarization, dissipation and absorption-attenuation ability of the coated composite to electromagnetic waves was the strongest, and within the range of 10–3000 MHz, the wave-absorbing properties and shielding properties to electromagnetic waves of the coated composite were the strongest. When the frequency was 1600.7 MHz, the value of the reflection loss of the sample was the minimum, which reached –7.15 dB. [ABSTRACT FROM AUTHOR]

Graphene was compounded with polyaniline to prepare a polyaniline/graphene composite coated fabric. The influence of the graphene on a series of properties of coated fabrics was discussed, and the results show that when the graphene content was 10 to 15% that of the polyaniline, the polarizing ability, loss ability and absorbing-attenuation ability of fabrics to electromagnetic waves were all stronger. As the coating thickness increases, the breaking strength and elongation at break of the fabric both showed an increase initially before decreasing; when the thickness was 0.5 mm, both fabrics were at their maximums, and the mechanical properties were at their best. The thermal decomposition temperature of the polyaniline/graphene composite coated fabric (411.3 °C) was higher than for the polyaniline coated fabric (402.9 °C) by 8.4 °C. The residue rate at 800 °C for the polyaniline/graphene composite coated fabric (18.83%) was larger than for the polyaniline coated fabric (14.17%) by 4.66%; the fabric had better thermal stability after the graphene was added. The graphene, with high thermal conductivity, was added to the polyaniline matrix as a filler, which can effectively fill the gaps between the polyaniline molecules, and an effective heat-conduction pathway forms and the heat-dissipation performance for the polyaniline/graphene composite coated fabric is improved. When the graphene content was 15% that of the polyaniline, the coefficient of thermal conductivity increases from 0.1011 W/mK to 0.1843 W/mK, an increase of nearly 82%. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to investigate the effects of structural parameters of fabric on thermal insulation properties of the coated fabric. Design/methodology/approach: The authors established a numerical model for the ablation of silicone resin-coated fabric under high heat flow, and the simulation results have been validated by quartz lamp ablation experiment. The model was used to investigate the effects of structural parameters of glass fiber fabrics on the heat transfer process of the coated fabric. Findings: The numerical values were in agreement with the experimental values. The thermal insulation of the coated glass fiber fabric was better than coated carbon fabric. Thermal insulation performance of the coated glass fiber fabrics was in order plain < 2/1 twill < 3/3 twill < 5/3 stain fabric. Increasing the warp density, from 100 to 180 ends/10 cm, the temperature of the back surface of the coated glass fiber fabric was reduced from 601°C to 553°C. Thermal insulation performance dramatically increased as yarn fineness went from 129 to 280 tex, and the temperature difference was 63°C. Research limitations/implications: In the ablation process, to simplify the calculation, the combustion reaction of silicone resin was ignored, which can be added in the future research. Originality/value: This paper provides the ablation model of the silicon-coated fabric based on the 3D geometry model to explore the influence of the structural parameters of coated glass fiber fabric on its thermal protection performance. [ABSTRACT FROM AUTHOR]

The single-layer graphene-coated fabrics was prepared using polyurethane as the matrix, graphene as the functional particle and the coating technology on the nylon. The influence of the content and coating thickness of graphene on the the electromagnetic property of single-layer graphene-coated fabrics were studied using the method of controlling variates. The result showed that when the graphene content was 20%, the real and imaginary parts of dielectric constant, the loss tangent, and the shielding effectiveness of the single-layer graphene-coated fabrics were all the largest. The coating thickness was 1.5 mm, the real part of the dielectric constant of the single-layer graphene-coated fabrics was the largest; when the coating thickness was 2 mm, the imaginary part and the shielding effectiveness of the dielectric constant of the single-layer graphene-coated fabrics was the largest; when the coating thickness was 1 mm, the loss tangent of the single-layer graphene-coated fabrics was the largest. [ABSTRACT FROM AUTHOR]

A glass fiber bulk yarn fabric with a graphite coating was produced, with the glass fiber bulk yarn fabric used as the base material, E44 epoxy resin as adhesive, low molecular 650 polyamide as curing agent and graphite, due to its low cost and low density, as the absorbing material. The influences of the graphite content, coating thickness and drying temperature on the dielectric constant and conductivity were the main focus of the investigation. The results showed that the glass fiber bulk yarn fabrics prepared with the graphite coating have good dielectric properties. In the frequency range used in the study, the content, drying temperature and coating thickness for the graphite coating were found to have a major influence on the real and imaginary parts of the dielectric constant, loss tangent value and the real and imaginary parts of the electrical conductivity. [ABSTRACT FROM AUTHOR]

In the high temperatures experienced in fire, radiant heat accounts for 80% of the total heat flow; therefore, improving the radiation protection is the best way to enhance the thermal protective performance of thermal insulation ablation resistant coated fabrics. To achieve this goal, the coating process and the ingredients used were optimized, spherical nano-SiO2 and other particles were added, and thermal insulation ablation resistant coated fabrics with high radiant heat reflectivity were prepared. The influence of the spherical nano-SiO2 content on the thermal protection performance of the prepared coated fabrics was investigated. Research showed that (1) the radiant heat reflectivity of the prepared coated fabrics improves significantly with increasing content of spherical nano-SiO2; when the mass fraction of spherical nano-SiO2 is 15%, the reflectivity of coated fabrics is at its largest, and its average value was 74.30%. At present, the average size of grains in samples increased 1.9 times; (2) after adding the spherical nano-SiO2, the thermal stability of the thermal insulation ablation resistant coated fabrics is significantly improved; the residual mass is as high as 88.49% at 1200°C, which is 18.77% higher than the residual mass of the coated fabrics with no spherical nano-SiO2 added at the same temperature. [ABSTRACT FROM AUTHOR]