The Field of the Invention

The invention relates to a nano additive coating method for increasing the electrical conductivity of fibers and I or their fabrics using coating solutions with adjusted surface tension and nanomaterial content by the application of two-dimensional nano materials such as graphene and one-dimensional nano materials such as carbon nanotubes to the surfaces of electrically non-conductive glass/quartz/basalt, polyester, nylon-based continuous or chopped fibers and / or their woven/nonwoven fabrics in single or hybrid configurations, without changing the surface chemistry.

Background of the Invention

In radar absorber systems, lossy dielectric (resistor) and I or magnetic composite materials are used to prevent back reflection of microwave radiation. It is observed that functional surfaces are being developed to achieve high performance for adjusting the electrical interactions, which is one of the most important problems in this field. In recent years, graphene began to be used as a conductive filler in resin and fabric interface due to its high surface area, high electrical conductivity, high thermal stability and mechanical properties [1 ].

In the literature, studies on various surface applications are known to increase the compatibility of graphene with glass, quartz, basalt based continuous or chopped fiber or woven, multiaxial, uniaxial form fabrics, textiles or tapes. In one of these studies, chopped glass fibers are calcined at 500 ^< C, then activated by immersing in silane bonding agent and bovine serum albumin solution, followed by immersion in graphene oxide (GO) solution to exhibit electromagnetic shielding in polyester resin [2], However, this type of applications may cause deterioration in mechanical properties by removing the sizing of glass fibers. In another study, GO sheets are covalently bonded to the glass fibers after increasing the glass fiber-polymer composite interface compatibility by applying silane bonding agent to the glass fibers [3]. In another study, the mechanical properties of the composite are examined by applying graphite nano-sheets exfoliated in 2-isopropanol to glass fibers with a brush, but the electrical conductivity values are not examined [4], Further, Yin et al. reported high mechanical performance, good interfacial crystallization and excellent intrinsic properties by coating the glass fiber with graphene by electrostatic self-assembly and embedding it in polylactic acid using silane bonding agents and GO [5]. However, most of these studies remain silent about the electrical conductivity or resistance values of fibers or fabrics. In the literature, there are limited studies on increasing the electrical conductivity of glass, quartz, basalt-based fibers and I or braided/nonwoven fabrics with graphene coating.

For example, it has been reported that by coating E-glass fibers with GO and reduced graphene oxide (rGO) using the electrophoretic coating method, the electrical conductivity of epoxy composites increases, and electromagnetic shielding is achieved by reducing the resistivity of the entire composite system to 450 Q.cm [6]. In one of the recently published studies, Fang et al. prepared continuous graphene-coated glass fibers using sol-gel and dip coating techniques and reported a minimum electrical resistance of 11 kQ after 20 cycles [7], Cao et al. successfully obtained rGO-coated silk fiber. The surface resistance decreased depending on the number of applications and the lowest resistance value was reported as 3.24 kQ cm- ¹ after 9 applications [8]. As hybrid materials, Kwon et al. coated carbon fibers with GO from a single solution using a surfactant and multi-walled carbon nanotube by anodic electrophoretic coating method [9],

On the other hand, a study is proposed in which carbon nanotube (CNT) and GO hybrid coating is performed using silane bonding agents on glass fibers [10]. However, no results have been published on the electrical conductivity of the hybrid structure. In this method, it is important to perform an effective reduction process to achieve high electrical conductivity.

Considering the present studies in the known state of the art, it is still important to design and manufacture broadband high-performance radar absorber structures with improved mechanical and electrical properties with 1 -dimensional (1 D) (for example CNT) and 2- dimensional (2D) (for example graphene) nano materials and it seems to be a subject that remains difficult. Compatibility of carbon-based nano materials with glass/quartz- based fibers, improving the interface properties and covering a large amount of surface area with the appropriate system can be cited among the important problems. Also, it is seen that the amount of carbon nanomaterial to be used in the production of radar absorbing structural fiber reinforced laminated composite structures; the appropriate electrical resistance level and the surface composition of the carbon material have not been clarified yet. It is important to use graphene-containing structures as a finishing material and as lossy material in order to preserve the mechanical properties of composite structures.

To summarize, it is seen that there are various studies on GO and CNT coating of glass fiber and carbon fibers in the known state of the art. On the other hand, the application of rGO, and especially the rGO/single-walled CNT (SWCNT) hybrid structure on glass/quartz/basalt based continuous or chopped fibers or woven/nonwoven fabrics by scalable manual/semi-continuous/continuous dipping method to provide them with high electrical conductivity is not yet known in the known state of the art.

The Chinese patent document with publication numbered CN1 11073222A in the state-of- the-art mentions a method for the preparation of graphene oxide/carbon nanotube reinforced glass fiber laminate. The said method comprises the steps of preparing the graphene oxide solution, obtaining the curing agent by grinding into the graphene oxide solution to obtain the composite material from the prepared solution, mixing and drying the obtained mixture, adding carbon nanotubes to a polyvinylpyrrolidone aqueous solution to obtain the coating solution and form the glass fiber fabric, coating the surface of the glass fiber fabric by immersion in the coating solution and drying it to obtain carbon nanotube modified glass fiber fabric. However, the reduction reaction with hydrazine hydrate is not performed in the said document. In the invention, which is the subject of the application, it is ensured that the electrical conductivity is increased, and the surface resistance value is decreased as a result of the reduction reaction performed by a reducing agent such as hydrazine hydrate.

The European patent document with the publication numbered EP3776728A1 in the known state of the art, mentions radar standing wave damping systems. In the said document, it is explained that the absorbent composite includes conductive filler materials. It is explained that the conductive filler material can also be graphene, carbon nanotube. However, it is stated that the absorber composite is also applied by dipping process. However, the reduction reaction with hydrazine hydrate is not performed in the said document. In addition, there is no step in the method for immersing the GO coated fabric in the carbon nanotube aqueous solution after reduction and drying.

Therefore, it is seen that in the known state of the art, there is a need for a homogeneous single or hybrid graphene/carbon nanotube coating method on glass/quartz/basalt based fiber and fabric having high electrical resistance in order to increase the electrical conductivity of glass/quartz/basalt based continuous or chopped fibers and woven/nonwoven fabrics and to reduce the surface resistance value by controlling the surface tension of the coating solution, the amount of nano materials in suspension and the coating thickness to achieve low surface electrical conductivity.

The term "non-conductive textile/fabric", which will be used for simplicity in the following descriptions and claims, refers to electrically non-conductive glass/quartz/basalt, polyester, nylon-based continuous or chopped fibers and / or their woven/non-woven fabrics.

The term "conductive textile/fabric", which will be used for simplicity in the following descriptions and claims, refers to glass/quartz/basalt, polyester, nylon-based continuous or chopped fibers and / or their woven/non-woven fabrics, which are made electrically conductive by the method of the invention.

Aim of the Invention

The aim of the present invention is to provide a nano additive coating method that enables to increase the electrical conductivity of non-conductive textile/fabric and decrease the surface resistance value without damaging the surface coating material (sizing) on the said non-conductive textile/fabric. In one application to achieve this aim the following steps are performed: GO coating is applied on the non-conductive textile/fabric using techniques of manually dipping/drying, semi-continuous coating/drying or coating/drying in a continuous system with a stable water-based suspension containing a single layer of GO with a progressively high hydrophilic level and at least 20% oxygen functional group, a hybrid structure is formed by establishing chemical bridges between functionalized SWCNT and GO and at the final step a reduction process is performed to increase the electrical conductivity of the non-conductive textile/fabric and to reduce the surface resistance value. It is also possible to coat a non-conductive textile/fabric with a single graphene or SWCNT coating using the methods and mechanisms described in the present invention. Coating performance is adjusted by the textile/fabric thickness and the design of the coating baths. In the manually immersion coating method, the coating baths are separated from each other by separators, so that the amount of nano materials in each compartment can be kept under control, and electrostatic interactions between non- conductive textiles/fabrics are prevented. Likewise, in semi-continuous and continuous immersion coating methods, the amount of nanomaterial in the bath must remain constant in each coating cycle.

The nano additive coating method developed to impart high electrical conductivity up to 100000 ohm/sq to 10 ohm/sq surface resistance levels to the non-conductive textiles/fabrics defined in the first claim realized to achieve the purpose of this invention and in the other claims depending on this claim includes the following steps: coating of non-conductive textile/fabric by immersing in a water-based suspension of at least one two-dimensional carbon nanomaterial (e.g. graphene derivatives) and I or immersing in a water-based suspension of at least one one-dimensional carbon nanomaterial (e.g. carbon nanotubes, nanowires) and I or coating with at least one two-dimensional carbon nanomaterial; drying the textile/fabric coated with two-dimensional carbon nanomaterial and I or one-dimensional carbon nanomaterial; reducing the textile/fabric coated and dried with two-dimensional carbon nanomaterial and I or one-dimensional carbon nanomaterial using at least one reducing agent, and drying of reduced textile/fabric.

In the preferred application of the method of the invention, single-walled carbon nanotube or oxidized single-walled carbon nanotube is used as a one-dimensional carbon nanomaterial. In the preferred application of the method of the invention, graphene oxide or single-layer nano layers with high oxygen ratios are used as two-dimensional carbon nanomaterial.

In an application of the invention, the nano additive coating method of the invention consists of repeating the following process steps more than once in the same order to form a loop: coating of non-conductive textile/fabric by immersing in a water-based suspension of at least one two-dimensional carbon nanomaterial (e.g. graphene derivatives) and I or immersing in a water-based suspension of at least one one-dimensional carbon nanomaterial (e.g. carbon nanotubes, nanowires) and I or coating with at least one two-dimensional carbon nanomaterial; drying the textile/fabric coated with two-dimensional carbon nanomaterial and I or one-dimensional carbon nanomaterial; reducing the textile/fabric coated and dried with two-dimensional carbon nanomaterial and I or one-dimensional carbon nanomaterial using at least one reducing agent, and drying of reduced textile/fabric;

With the method of the invention, the following are provided: using core-shell structures which are non-conducting inside and conducting outside, to control the absorption/reflection mechanisms of electromagnetic waves, changing the conductivity of the outer shells, using graphene and CNT hybrid structures as absorbers, using waterbased solutions of nano-materials without the need for refinishing, and minimizing environmental impact while maintaining the mechanical strength of the fiber/fabric.

Contrary to the studies for coating fiber, yarn and cord, this invention makes it possible to coat non-conductive textiles/fabrics with large surface area with nano additives such as graphene and SWCNT, and it is a method suitable for upscaling. The amount of nano additives on the surface of non-conductive textiles can be controlled by the coating time.

In the applications of the invention using immersion coating methods, in order to keep the coating quality the same and repeatable in the coating process step, it is ensured that each coating bath is separate, that non-conductive textiles/fabrics enter the baths separated by separators in the manual coating method to prevent electrostatic interaction and that the amount of nano additives in each bath remains the same. In order to make a homogeneous coating during the immersion and extraction processes, the textile/fabric is stretched in U-shaped cages hanging upside down. In addition, all chemical coating processes described prior to this patented technology are also suitable for semi- continuous and fully continuous coating methods.

With the invention, it is made possible to use woven/non-woven fabrics coated with single or hybrid nano additives and thermoset and thermoplastic polymer composite structures with high conductivity and high performance in the production of prepregs and composites, which are the intermediate products.

Detailed Description of the Invention

Preferred embodiments of the invention are described in this detailed description only for a better understanding of the subject and without causing any limiting effect.

In the method of the invention, at least one two-dimensional carbon nanomaterial and / or at least one two-dimensional carbon nanomaterial is coated on non-conductive textile/fabric by sequential immersion coating method. GO with preferably high surface oxygen groups is selected as a two-dimensional nanomaterial, and its stable suspensions are prepared in water-based solvent systems such as surfactants and water, water-ethyl alcohol mixtures to impart high wetting properties. In an application of the invention, a hybrid lossy material is formed with GO on a non-conductive textile/fabric surface, preferably by choosing SWCNT as a one-dimensional nanomaterial. Afterwards, reduced graphene oxide (rGO) and carbon nanotubes are obtained by reducing oxidized carbon nano materials to increase electrical conductivity. In the method of the invention, SWCNT can be used both in its oxidized form and with its high-carbon grade variety to hybridize with GO. In the method of the invention, the reducing step must be applied in order to obtain high electrical conductivity in the last stage of the single or hybrid coating process.

In the preferred embodiment, a high homogeneity suspension is prepared in 0.1 %-1 % by weight GO water and I or water-ethyl alcohol mixtures (varying ratios by volume 50:50- 95:5) using an ultrasonic probe. Solvent systems are optimized to control surface tensions and prevent textiles/fabrics from wrinkling during immersion coating. Single layer GO layers, preferably produced by chemical exfoliation method, containing 20-50% surface oxygen groups, are applied to non-conductive textiles/fabrics by immersion coating method for 1 -180 minutes. Afterwards, the textiles/fabrics soaked in the said suspension are dried at 50-150 ‘C for 5-150 minutes. Then, the reduction reaction is carried out at 50-90 <0 for at least 2 hours, preferably using a s trong reducing agent such as hydrazine hydrate, in order to reduce the oxygen groups on the surface preferably to 5-20% and increase the electrical conductivity. In alternative embodiments of the invention, it is also possible to use reducing agents such as NaOH, L-ascorbic acid or hydroquinone as reducing agents. Surfactants such as sodium dodecyl sulfate (SDS), sodium dodecyl benzene sulfate (SDBS) and sodium naphthalene sulfonate affect the concentration and solvent system coating quality. Lower conductivity values were measured on the coatings made with GO- based suspensions prepared in distilled water-ethyl alcohol mixture (volume varying water/ethyl alcohol ratio: 50:50-95:5) and GO:surfactant ratios of 1 :1 -1 :10 by weight compared to aqueous suspension without surfactant. Surface tension of GO suspensions directly affects drying processes and surface resistance values. For the homogeneous drying process, the ethyl alcohol ratio in the suspension is preferably adjusted between 1 % and 40%.

In the method of the invention, in order to increase conductivity, GO-CNT hybrid coatings can be made instead of only single GO coating. For this purpose, firstly, 0.1 -0.6 grams of SWCNT is oxidized under reflux in a mixture of sulfuric acid (H2SO4)/nitric acid (HNO3) (5:1 -2:1 by volume) preferably at 30-80 <0 for 12-48 hours. At the end of the reaction, the acid mixture is diluted with water and the separation stage is started. Oxidized SWCNT (ox-SWCNT) separated by filtration or centrifugation is dried at 50-100 ‘C for 12-48 hours.

After oxidation and drying of the SWCNT, 0.1 -0.5 grams of ox-SWCNT is dispersed in distilled water with an ultrasonic probe for 30-180 minutes, after which ox-SWCNT suspension is prepared by adding surfactant to obtain an ox-SWCNT:surfactant (e.g. SDS) ratio of 1 :1 -1 :10 by weight and mixed with a magnetic stirrer at the lowest speed for 10-60 minutes until the foaming ends. Textiles/fabrics previously coated with GO are immersed into this prepared suspension and coated for 10-60 minutes at room temperature. Textiles/fabrics coated with GO and ox-SWCNT are hung vertically and dried at 90-150 <C for 5-30 minutes.

The textile/fabric coated with GO and ox-SWCNT/SWCNT is reduced by a strong reducing agent, preferably hydrazine hydrate, for 1 -5 hours at 30-90 ‘C. The hydrazine hydrate ratio used in the invention is adjusted according to the amount of GO, and preferably the GO:hydrazine hydrate ratio is adjusted as 1 :1 -1 :3 by weight. Reduced fabrics are hung to dry for 5-30 minutes at 90-150 ‘C.

In an embodiment of the invention, low surface resistivity values can be obtained by coating and reducing SWCNT on the textile/fabric surface independently of GO. Likewise, in SWCNT water-based solvent systems smaller than 2 nm in diameter, 1 -60 minutes of coating is carried out with SWCNT/ox-SWCNT:surfactant varying ratio of 1 :1 -1 :10 by weight. Then, hydrazine hydrate ratio used as the reducing agent is adjusted according to the amount of SWCNT, and the reduction process is carried out at 50-90°C for at least 3 hours, preferably by adjusting the SWCNT/ox-SWCNT: hydrazine hydrate ratio as 1 :1 - 1 :3 by weight.

It is possible to use natural or heat-assisted drying approaches, such as infrared drying, to eliminate fluctuations and marks caused by gravitational fluid flow during drying of textiles/fabrics. Within the scope of this patent, they can be hung horizontally, vertically or diagonally, while drying textiles/fabrics, depending on the coating direction.

Example 1 : GO and rGO Coating Steps on Non-Conductive Textile/Fabric:

The method for coating only rGO non-conductive textile/fabric according to an exemplary embodiment of the invention is described in stages below. In the said method, the textile/fabric weight is preferred as 100-300 grams/ m ² (gsm) to provide a homogeneous coating. As an example, 1 10 gsm glass fabric by weight was chosen for coating studies. i) GO Coating Step:

GO with high oxygen groups is preferably prepared by Hummer's modified method [1 1 ]. A suspension is prepared by dispersing 0.5 grams of GO in 200 mL of distilled water for 15 minutes with an ultrasonic probe. It is also possible to use surfactants such as water- ethyl alcohol mixtures to reduce the surface tension in the suspension preparation and sodium dodecyl sulfate (SDS) and sodium dodecyl benzene sulfate (SDBS) to adjust the viscosity. The GO coating process is carried out by immersing the textile/fabric in 0.25% suspension at room temperature for at least 30 minutes. The textile/fabric coated with GO is dried at 120 <0 for 15 minutes. ii) Reduction Step with Hydrazine Hydrate

0.50% by weight hydrazine hydrate solution (d=1 .029 g/mL) is prepared in distilled water and the prepared solution is heated to 50 ^< C. Then, the GO coated textile/fabric is kept in hydrazine hydrate solution at 50 <0 for 3 hours. Th e hydrazine hydrate ratio is adjusted according to the amount of GO and the ratio of 1 :2 by weight is maintained.

Hi) Drying Step:

Textiles/fabrics subjected to coating processes are dried by hanging vertically for 15 minutes at 120 <0 after the said coating processes. iv) Sequential GO-rGO Coating-Reduction Cycles:

At the end of the coating-reduction-drying cycle described above, hereinafter referred to as the first cycle, the second and third cycles are carried out by applying the same method. The same GO suspension can be used in 3 cycles. On the other hand, due to the decrease in the amount of GO in the same GO suspension in the fourth cycle, an increase in surface resistance was observed. In addition, the hydrazine hydrate solution, the preparation process of which is described above, can be used for 3 cycles.

Table 1 : Surface resistivities of rGO coated glass fabrics (110 gsm) prepared with GO suspensions with different solvent systems

Electrical resistivities are measured with a 5 ¹ /2 digit multimeter with a 2-lead.

As a result of the conducted studies, the following findings have been reached for non- conductive textiles/fabrics that have been made conductive by rGO coating:

• It has been found that the thickness of the non-conductive textile/fabric affects the coating quality and surface resistance. For example, better results were obtained with 1 10 gsm textiles/fabrics than with 163 gsm textiles/fabrics. Most measurements with 1 10 gsm textiles/fabrics are in the kilo-ohm range. The highest conductivity was observed in 1 10 gsm textiles/fabrics.

• It was found that the conductivity increased with the GO coating time and the coatings made in less than 10 minutes did not create high conductivity.

• For textiles/fabrics of 110 gsm and less, 30 minutes of GO coating time was found to give the best results. The hydrazine hydrate reduction time for these samples was optimized as 3 hours at 50 ^< C. For denser and heavi er textiles/fabrics, reduction time needs to be increased

• It was found that the coatings were homogeneous and stable for each sample.

• The highest performance coating was obtained by optimizing the following parameters. o GO concentration o Number of GO coating cycles o hydrazine hydrate concentration o Number of reduction cycles

• When the GO/hydrazine hydrate ratio exceeds 1 :4 by weight, shedding from the rGO coated textile/fabric surface was observed due to the high amount of reducing agent. GO/hydrazine hydrate ratio 1 :2 by weight was determined as the most ideal.

• As the number of GO coating and reduction cycles increased, the surface resistance value decreased.

• As the GO concentration in the prepared suspensions decreased, the surface resistivity increased and the conductivity decreased.

• The same GO suspension can be used for three cycles, reducing the cost.

• Graphene should be used as a sheet in suspension; plate graphene structures are not suitable for achieving high electrical conductivity values.

Example 2: Hybrid rGO-SWCNT Coating Steps on Non-Conductive Textile/Fabric:

According to an exemplary embodiment of the invention, the steps of coating and reducing GO and SWCNT/ox-SWCNT on non-conductive textile/fabric, are described. In this example, the non-conductive textile/fabric is first immersed in a water-based GO suspension for 30 minutes to coat the surface with GO. The textile/fabric coated with GO is dried at 120 <0 for 15 minutes. The textile/fabr ic dried by coating GO is then immersed into the supplied SWCNT water-based suspension and the suspension made with ox- SWCNT to detect the effect of oxygen groups and increase bonding interactions.

Two different coating methods developed to reduce the surface resistance of non- conductive textiles/fabrics were validated using a 1 10 gsm glass fiber fabric, and these alternative methods are explained below: 1. Phased hybrid coating method using GO and functional SWCNT:

• GO suspensions are prepared in 0.25% water and water-ethyl alcohol mixtures and non-conductive textiles/fabrics are coated by immersion method at room temperature for 30 minutes. Graphene oxide coated textiles/fabrics are dried at 120 <0 for 15 minutes.

• A minimum of 0.30 grams of SWCNT (increasing the amount will vary depending on the specific gravity of the SWCNT) in 100 mL of H2SO4/HNO3 (v:v= 3:1 ) mixture is oxidized under reflux for 24 hours at 50 ^< C. The acid mixture obtained at the end of this reaction is diluted with water, passed through the filtration or centrifugation stages, and then oxidized ox-SWCNT is obtained and dried at 80 <C for 24 hours.

• 0.1 -0.5 grams of dried ox-SWCNT is dispersed in 100 mL distilled water with an ultrasonic probe for at least 2 hours. Then, the mixture obtained by adding SDS in a ratio of 1 :1 -1 :10 by weight of ox-SWCNT:SDS is mixed with a magnetic stirrer for at least 30 minutes at the lowest speed until the foaming ends. Textiles/fabrics previously coated with GO are covered with ox-SWCNT by immersing in this suspension obtained at room temperature for 30 minutes. Textiles/fabrics coated with GO and ox-SWCNT are hung vertically and dried at 120 <C for 15 minutes.

• Textile/fabric coated with GO and ox-SWCNT and dried is reduced in hydrazine hydrate solution for 3 hours at 50 ^< C. The hydrazin e hydrate ratio is adjusted according to the amount of GO and the ratio of 1 :2 by weight is maintained.

• Reduced textiles/fabrics are hung vertically to dry at 120 ‘C for 15 minutes.

2. Direct hybrid coating method with a single suspension containing GO and SWCNT:

In the said method, suspensions containing 0.1 %-1 % by weight GO and 0.1 %-0.5% by weight SWCNT are prepared. The non-conductive textile/fabric is immersed in the prepared hybrid nano additive suspension for at least 30 minutes at room temperature. After reducing and drying processes at 50°C for at least 3 hours in hydrazine hydrate solution, hybrid nano additive conductive textile/fabric is prepared. In summary, this invention enables non-conductive textiles/fabrics to gain high electrical conductivity by coating them with nano additives as a single or hybrid coating. In Table 2 and Table 3, the average resistivity values obtained with the coating materials applied to 1 10 gsm and 163 gsm woven glass fabric are given. As the covered fabric area grows, the evaporation rates of the solvents in the suspensions, the surface tensions of the solution and the suspension composition should be optimized in order for the resistance values to be stable and homogeneous.

Table 2: Surface resistivity of rGO/SWCNT coated glass fabrics (1 10 gsm) with GO suspension with different solvent systems according to the coating procedure

Table 3: Surface resistivity of rGO/SWCNT coated glass fabrics (163 gsm) with GO suspension with different solvent systems

As a result of the conducted studies, the following findings were obtained for textiles/fabrics coated with rGO/SWCNT hybrid nanoadditives to impart them conductivity:

• Combining oxidized (functionalized) SWCNTs (ox-SWCNT) with GO layers resulted in the formation of more efficient hybrid structures compared to the direct use of SWCNTs with a high carbon percentage (94% and above). • It has been found that the degree of purity of SWCNTs has a significant effect on the electrical resistivity, and SWCNTs with less than 95% purity increase the resistivity.

• SWCNT amount more than 0.4% causes agglomeration on the surface of non- conductive textiles/fabrics. • SWCNT :GO ratios by weight should be optimized in suspensions prepared against local clumping and crusting on the surface of non-conductive textiles/fabrics in SWCNT and GO mixtures used in direct coating.

• In the hybrid nanomaterial coating system, low resistivity and high conductivity were detected in fabrics of different weights.

• Low resistivity values have been achieved in a single cycle using hybrid additives.

With the method of the invention, the resistivities of textiles/fabrics coated with rGO- SWCNT hybrid nano additives were measured in the range of 10-800 Q. cm ^-1 . In glass/quartz/basalt fabrics coated with rGO only, resistance level of 15-30 kQ. cm ¹ is achieved after 3 times GO coating and hydrazine hydrate reduction cycle.

The present invention also relates to electrically conductive textile/fabric obtained in accordance with the method described above. In an embodiment of the invention, the conductive textile/fabric has a surface resistance of 10000 ohm/sq - 10 ohm/sq and is suitable for use as a radar absorber. In another embodiment of the invention, the conductive textile/fabric has a surface resistance between 100000 ohm/sq - 1000 ohm/sq and is suitable for use as an anti-static layer and I or in embedded defrosters/heaters. In another embodiment of the invention, the conductive textile/fabric has a surface resistance between 10000 ohm/sq - 100 ohm/sq and is suitable for use in embedded sensors. In another embodiment of the invention, conductive textile/fabric has a surface resistance between 100 ohm/sq - 10 ohm/sq and is suitable for use in wearable electronic components.

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