PROTECTIVE SUIT FOR HOSTILE ENVIRONMENTS WITH ELECTROMAGNETIC RADIATION SHIELDING EFFECT AND NANOGENERATOR OF ELECTRICITY THROUGH TRIBOELECTRIC EFFECT

Abstract

Protective suit for harsh environments made of a fabric containing at least one triboelectric nanogenerator comprising at least one low electronegativity layer and at least one high electronegativity layer, wherein friction between the layers generates voltage pulses whose amplitude and waveform depend on the frequency, speed, acceleration, force, and displacement of said layers, and wherein the fabric further comprises sensors configured to collect the voltage pulses emitted by friction between the high and low electronegativity layers of the triboelectric nanogenerator.

Description

PROTECTIVE SUIT FOR HOSTILE ENVIRONMENTS WITH ELECTROMAGNETIC RADIATION SHIELDING EFFECT AND NANOGENERATOR OF ELECTRICITY THROUGH TRIBOELECTRIC EFFECT Field of invention The invention relates to a suit or, more generally, personal protective equipment for hostile environments, such as a spacesuit or a CBRN (chemical, biological, nuclear, and radiological) suit, which offers the user protection against, among other things, ionizing and non-ionizing radiation. The suit or garment of the invention has an electromagnetic radiation shielding effect, generates electricity via the triboelectric effect, and can optionally be flame retardant. This suit can be used in space applications, as well as in environments where ionizing and non-ionizing radiation, electromagnetic radiation, and / or particle jets may be present, where monitoring the movement of objects and people is required, and in environments that may be explosive, exposed to fire, and / or subjected to high levels of radiation. State of the art The invention relates to a suit or, more generally, personal protective equipment for harsh environments. The fabric, which can be either rigid or soft, has a shielding effect and therefore acts as a barrier against electromagnetic radiation. It can generate electricity based on the triboelectric effect and may also be flame retardant. Thanks to the triboelectric effect, the material can monitor the wearer's movement, optionally emitting warning signals based on readings from various integrated sensors. This invention is considered necessary and highly useful for space applications and in environments where ionizing or non-ionizing radiation, as well as electromagnetic radiation and / or particle jets, may be present. It is also relevant where monitoring the movement of objects and people is necessary, and in environments that may be explosive or exposed to high temperatures or fire. The objective is to provide a material that, at a minimum, provides electromagnetic shielding and generates a riboelectric effect by producing nanoelectricity on its own. Additionally, as an advantageous optional effect, the suit also desirablely possesses the ability to extinguish flames in the presence of fire. In this way, the suit protects against electromagnetic radiation from cosmic rays and electromagnetic radiation in different regions of the radiofrequency spectrum. Furthermore, this suit can also be used by nuclear power plant operators, for which it must be flame retardant. Therefore, flame retardant elements are incorporated into the polymer material or fabric during its manufacture. Numerous examples of useful materials for electromagnetic radiation shielding in suits of the type used in the present invention can be found in the literature. In [1], a review of different radiation-shielding materials is presented: Mu-metal, a high-permeability alloy composed of 14% iron, 5% copper, 1.5% chromium, and 79.5% nickel; brass; aluminum; silver; nickel; stainless steel; metallized plastics; and conductive carbon / graphite composites. These latter materials present problems such as corrosion, high density, or brittleness. Also included are plastics, such as those with conductive coatings, others with internal conductive fillings, and still others that are intrinsically conductive polymers. All of these latter materials utilize an internal metallic foil as a radiation shield.Regarding polymers with metals or metallized materials, we have PPY or poly(3,4-ethylenedioxythiophene) PEDOT fabric compounds, with a shielding of 36 dB for the 300 MHz frequency range [2]; PPY based on intrinsically hot adhesives [3], with more than 30 dB and for an absorption frequency of 300 MHz; PPY / p-toluenesulfonate compounds with more than 40 dB, for an absorption band from 300 MHz to 2 GHz; PPY compounds impregnated with conductive polymers [4], with 26 dB in the 1 to 2 GHz frequency range; with PPY impregnated with microporous polyethylene [5], which in the 10 kHz to 1 GHz frequency range presents 40-50 dB. Regarding shielding, no materials have been found in the literature that function as sensors with shielding values ​​up to 140 dB within a measurement frequency range of 30 MHz to 1.5 GHz (and less so from 1 MHz to 3 GHz) according to the ASTM D4935 standard, along with free-space shielding measurements with minimum values ​​from 2.6 GHz to 40 GHz. Furthermore, no materials possess the characteristic of being triboelectric, such that by combining the layers they can generate electricity and thus monitor movement while shielding electromagnetic radiation. Nor do they include flame-retardant materials that would make them fireproof or highly resistant to fire. In addition to all of the above, no materials have been found that shield high-energy radiation such as gamma rays, X-rays, or neutrons. There are some triboelectric generators in the literature that may have a flame-retardant component [6][7], however, none have been shown to possess shielding properties, fire protection, and high electrical generation efficiency. Similarly, alarm sensor materials exist, but none have been found to have shielding properties [8][9]

[10] . Summary of the invention Therefore, it remains a great challenge to design and manufacture a suit, which may be for space (20) or simply for use in hostile work environments, that combines the characteristics of having a high electromagnetic shielding and making use of the triboelectric effect, overcoming the disadvantages of known suits. The inventors of the present invention have identified that it is possible to achieve this objective by means of a protective suit or garment for hostile environments that is made at least partially of a fabric comprising at least one triboelectric nanogenerator composed of a layer of low absolute electronegativity having a charge density of less than 100 C / m2 and at least one layer of high electronegativity having an absolute charge density greater than 200 C / m2, with a dynamically generated charge density and for a pressure of 1.6 kPa between layers less than 0.35 mC / m2, where both layers are in contact and the friction between the layers generates voltage pulses whose amplitude and waveform depend on the frequency, speed, acceleration, force and relative displacement of said layers, and where the suit also comprises sensors configured to collect the voltage pulses emitted by the friction between said layers and send them to signal acquisition, processing and / or communication systems. With regard to electromagnetic shielding, the material of the invention is preferably based on graphene, and a large quantity of it can be incorporated. In particular, graphene oxide and reduced graphene oxide are preferably used, as these are conductive particles that increase the dielectric constant, thus shielding electromagnetic radiation. Similarly, an increase in porosity will also enhance this shielding by allowing radiation to interact with the material. Furthermore, the inclusion of metallic nanoparticles, along with the metal electrodes that extend as flexible sheets wrapping the suit's bilayer on each side (Al or Cu), will also increase shielding. For the triboelectric characteristic, materials such as nylon and PVA (polyvinyl alcohol), which are highly electropositive, are used, as well as others such as PVDF (polyvinylidene fluoride), which are highly electronegative, or PDMS (polydimethylsiloxane), which are somewhat less electronegative but harder. All of these are ideally mixed with the appropriate proportions of chemicals to be flexible and conform to the suit. Only when buttons are used to signal emergencies can they be made more rigid and function as electrical triggers. The material used in the suit of the invention combines an electropositive face with an electronegative face. Materials are sought that meet the shielding requirements in the frequency range of the ASTM D4935 standard, that is, from 30 MHz to 1.5 GHz, and, outside of this standard, from 1 MHz to 3 GHz for coaxial waveguide measurements and from 2.6 GHz to 40 GHz for free-space measurements. Shielding is also required for gamma, X-ray, or neutron radiation. Different possibilities for the electropositive and electronegative faces of the material of the invention would be summarized in the following table: Table 1: where the meaning of the acronyms is as follows: PVA: Polyvinyl alcohol PVDF: Polyvinylidene fluoride PANI: APS (8-aminopyren-1,3,6-trisulfonic acid) + (3-aminopropyl)triethoxysilane + aniline. The combination of aniline with APS and (3-aminopropyl)triethoxysilane results in a material called PANI with specific properties, including improved conductivity and controlled morphology due to the presence of the sulfonic dopant and the potential additional functionality of the silane. PDMS: Polydimethylsiloxane. GMP: Graphene. GO: graphene oxide. The material used in the suits of the present invention therefore has a high electronegativity layer and a low electronegativity layer, also referred to as the electropositive face, such that friction between them produces voltage pulses whose amplitude and waveform depend on the frequency, speed, acceleration, force, and displacement of the layers. These parameters can therefore be calculated from the indicated voltage pulses. In the present invention, "high electronegativity" means an absolute charge density greater than 200 C / m², while "low electronegativity" means a charge density less than 100 C / m², with a dynamically generated charge density for a pressure of 1.6 kPa between layers of less than 0.35 mC / m².Therefore, from these pulses it is possible to calculate the user's movement data, which can be very important, for example, in cases of astronauts or any other operator who has to work in restricted and / or dangerous areas. Finally, to achieve the optional flame retardant characteristic, these materials can optionally contain phosphorus compounds, if this function is necessary or recommended. The compounds used for this purpose are of the PO type, with phosphorus in its oxidized state. These materials do not change the shielding, but they do reduce the efficiency in electrical generation, which decreases by a maximum of 3% in most cases. One compound with these characteristics is ammonium polyphosphate (APP). The fact that these materials can be used as nanotriboelectric energy generators makes them suitable for motion monitoring and as triggers to initiate the operation of an electronic circuit. This allows them to be used as long-range remote warning devices, utilizing communication protocols such as LoRa. These motion-generated signals can also be monitored locally or remotely. Because the triboelectric generators do not use batteries and the communication chips operating under the LoRa protocol have very low power consumption, the system is self-sufficient for years, operating in standby mode when inactive. Ideally, the battery-free energy generator could operate indefinitely. On the other hand, the material used in the suits of the invention can be manufactured with a hard polymer such as PLA, allowing for applications such as aircraft or helmet protection. However, if these materials are softer, such as very thin polymers, they can be used as part of the fabric in suits exposed to radiation and fire (if they have flame-retardant coatings), such as an astronaut's suit or the suit of a radioactive facility operator. The wearer's movement can be monitored thanks to the triboelectric effect. Brief description of the figures To complete the description and provide a better understanding of the invention, a set of drawings is provided. These drawings form an integral part of the description and illustrate preferred embodiments of the invention. The drawings comprise the following figures. Figure 1 shows various material embodiments according to the present invention, using different triboelectric generators with different electrical generation properties, their flame retardant characteristics where applicable, and their various electromagnetic shielding properties. These triboelectric generators are as follows: PVDF (2), PVA (3), PVDF-GO15% (4), PVA-GO100% (5), PDMS (6), PDMS-m (7), PVA-PANI (8), PET (9), Cu (10), PVA+PANI+GO15% (11), PDMS+PVA+PANI (12), PVA-GO30% (13), PVA+gmp (30%) (15) (16). The numbers in parentheses refer to the layer numbers shown in Figure 1. All may contain phosphorus compounds as flame retardants, such as APP. Furthermore, for suit applications, PDMS, PVA, PCDF, PANI, etc., polymers should preferably be very thin layers and may be substituted with nylon or cotton, among other fabrics. PLA (polylactic acid) fibers are also an option.The materials used in the present invention, including oxidized (GO) or reduced (gmp) graphene, shield both non-ionizing and ionizing radiation, particularly gamma, X-rays, and neutrons. Metallic nanoparticles can be added to shield radio waves in the spectra discussed in the manuscript, as well as high-energy ionizing radiation. Figure 2 shows the example of a suit, such as an astronaut's spacesuit, that shields against cosmic radiation and is fire-resistant with a triboelectric double layer that will allow the monitoring of certain physical parameters. Figure 3 shows examples of triboelectric pulses for PVA-GO 100% / PDMS with an applied force of 600 N and a frequency of 0.2 Hz (28) and the same but PDMS / PVA+PANI GO 100% with a force of 1000 N (29). Figure 4 shows examples of a Voltage vs. Force calibration curve such as that made with the PDMS / PVA-PANI-GO15% bilayer. Figure 5 shows spacesuit fabrics over the person and their radiation shielding, as well as the design needed to remotely inform (with LoRA protocols, for example) any internet-enabled device about the movement of the astronaut or user and / or if there is an emergency situation due to fire, heat, or excess humidity. Figure 6 shows the use of DL (Deep learning) to classify physical magnitudes such as amplitude and frequency, which involve speed, acceleration, displacement, and force of the detected motion. Detailed description of the invention The garment or clothing of the invention can be made using different triboelectric energy nanogenerators made from the materials listed in Table 1 above, with varying electrical self-generation efficiencies, shielding properties, and flame retardancy. In the present invention, a "triboelectric nanogenerator" is understood to be a device that converts mechanical energy into electrical energy by harnessing the triboelectric effect, that is, by generating static electricity when different materials are rubbed or brought into contact. Therefore, in its simplest form, a triboelectric nanogenerator is simply composed of two layers of different materials in contact with each other, having a substantial difference in electronegativity. In the present invention, the materials used to make these triboelectric nanogenerators are selected from those listed in Table 1 above. Accordingly, in one aspect, the invention relates to a protective suit for harsh environments made at least partially of a fabric comprising at least one triboelectric nanogenerator composed of a high electronegativity layer having a charge density greater than 200 C / m2 and a low electronegativity layer having a charge density less than 100 C / m2, with the charge density generated dynamically and for a pressure of 1.6 kPa between layers less than 0.35 mC / m2, wherein both layers are in contact and where the friction between the layers caused by the movement of the suit user generates voltage pulses, characterized in that the suit further comprises sensors configured to collect the voltage pulses emitted by the triboelectric nanogenerator and send them to signal acquisition, processing and / or communication systems. The following materials have been manufactured that can act as triboelectric energy generators with shielding properties. The list below indicates the materials that constitute the electronegative and electropositive layers, respectively, for each triboelectric generator. The number following the acronym for graphene (gmp) or graphene oxide (GO) is the weight percentage of graphene or graphene oxide relative to the weight of the corresponding layer. 1) PVA / PVDF-GO 15%, 2) PVA-GO 100% / PVDF, 3) PVA-GO 15% / PVDF-GO 15%, 4) PVA-GO 100% / PVDF-GO 15%, 5) PDMS (m) / PVA, 6) PDMS / PVA-PANI, 7) PDMS / PVA-PANI-GO 15%, 8) PDMS / PVA-GO 100%, 9) PVA+GMP 30% / PDMS, They all have shielding properties and high electrical efficiency. Graphene and graphene oxide in varying proportions are embedded in the fabric to provide electromagnetic shielding in the frequency range specified by ASTM D4935, i.e., from 30 MHz to 1.5 GHz, and outside this standard, from 1 MHz to 3 GHz for coaxial waveguide measurements and from 2.6 GHz to 40 GHz for free-space measurements. The fabric with monolayer and bilayer graphene shields high-energy radiation (gamma, X-rays, and neutrons). Metallic nanoparticles can be added to further enhance the shielding. In these types of materials, the order of electrical efficiency is inversely related to that of electrical shielding, as graphene reduces electrical efficiency. Shielding is primarily determined by the amount of graphene and graphene oxide present in the sample. Graphene generally reduces triboelectric efficiency slightly. Thus, the order from highest to lowest shielding efficiency would be as follows: PDMS / PVA+gmp (30%) > PDMS / PVA-GO-100% > PDMS / PVA-PANI-GO 15% > PDMS / PVA-PANI > PVA-GO100% / PVDF-GO15% > PVAGO100% / PVDF > PVA / PVDF-GO15% > PVA-PANI-GO 15% / PVDF > PDMS (m) / PVA. For the compounds described, electromagnetic shielding values ​​above 20 dB are considered high, and values ​​below 12 dB are considered low for frequencies below 3 GHz. For frequencies between 3 GHz and 40 GHz, electromagnetic shielding values ​​above 60 dB are considered high, and values ​​below 40 dB are considered low. Thus, PDMS / PVA+gmp (30%) will have a high level of shielding, while PVA-PANI-GO 15% / PVDF will have a low level of shielding. With metallic strips, the shielding is superior and can reach more than 50 dB for all TENGs across the entire frequency range (1 MHz - 40 GHz). However, the more graphene / GO there is in the layers, especially with PVDF, the lower their electrical efficiency will be compared to those with only PDMS or PVDF. Thus, the electrical efficiency, characterized by the difference in electronegativity between layers, will be as follows: PVA-PANI-GO15% / PVDF > PVA-GO100% / PVDF > PVA-PANI-GO15% / PDMS > PDMS / PVA+gmp 30% > PDMS / PVA-GO-100% > PDMS / PVA-PANI > PDMS (m) / PVA > PVA / PVDF-GO15% > PVA-GO 100% / PVDF-GO15%. One way to evaluate its electrical efficiency is by assessing its response when pressures of specific values ​​are applied, such as 100 N per 25 cm² (1.6 kPa). Its electrical efficiency would then be as follows: PVA-PANI-GO15% / PVDF (<0.7 mC / m2) > PVA-GO100% / PVDF (<0.6 mC / m2) > PVA-PANI-GO15% / PDMS (<0.5 mC / m2) > PDMS / PVA+gmp 30% (0.4 mC / m2) > PDMS / PVA-GO-100% (<0.3mC / m2) > PDMS / PVA-PANI (<0.2 mC / m2) > PDMS (m) / PVA (<0.15 mC / m2) > PVA / PVDF-GO15% (<0.1mC / m2) > PVA-GO 100% / PVDF-GO15% (<0.08 mC / m2) . With these materials, the following triboelectric generators have been produced according to the invention, using the electropositive and electronegative layers indicated, where the numbers in parentheses correspond to the numbering of the layers in Figure 1: • The triboelectric generator B has an electropositive layer of PVA (3) and an electronegative layer PVDF-GO 15% (4). • The triboelectric generator C has a 100% PVA-GO electropositive layer (5) and a PVDF electronegative layer (2). • The triboelectric generator E has an electropositive layer of 100% PVA-GO (5) and an electronegative layer of 15% PVDF-GO (4). • The triboelectric generator F has an electropositive layer of PVA+PANI+GO 15% (11) and an electronegative layer of PVDF (2). • The triboelectric generator G has an electropositive layer of PVA (7) and an electronegative layer of PDMS-m (3) (modified with nanohorns). • The triboelectric generator H has an electropositive layer of PVA-PANI (12) and an electronegative layer of PDMS (6). • The triboelectric generator I has an electropositive layer of 100% PVA-GO (5) and an electronegative layer of PDMS (6). • The triboelectric generator J has an electropositive layer of PVA+gmp 30% (15) and an electronegative layer of PDMS (6). When PVDF is used, it can be replaced by PDMS (as in the triboelectric generator F). All these materials have shielding properties and high electrical efficiency. Optionally, copper or aluminum sheets and PET for protection can be added to all of these materials. And in certain cases, lead. In a preferred embodiment, the triboelectric nanogenerator has an absolute charge density not exceeding 350 C / m2 in dynamic conditions and for a pressure of 1.6 kPa between layers less than 0.35 mC / m2. In another embodiment, the low electronegativity layer comprises at least one fabric selected from the group consisting of nylon, cotton, PDMS, PLA or nanohorn-modified or unmodified PVA, which is impregnated in a material selected from polyvinyl alcohol (PVA), graphene (gmp), graphene oxide (GO) and PANI (8-aminopyren-1,3,6-trisulfonic acid (APS) + (3-aminopropyl) triethoxysilane) + aniline) and mixtures thereof. In another embodiment, the fabric is impregnated in one of the following combinations of materials: PVA, PVA-gmp 30%, PVA-GO 100%, PVA-PANI GO 15% and PVA-PANI or combinations thereof, where the percentages indicated refer to the percentage by weight of the respective component on the weight of the layer. In another embodiment, the high electronegativity layer with a charge density greater than 200 C / m2 for a strength greater than 1.6 kPa comprises at least one fabric selected from nylon, cotton, PDMS, PLA or PVA modified with nanohorns or unmodified, which is impregnated in a material selected from polyvinylidene fluoride (PVDF), polydimethylsiloxane (PDMS), graphene oxide (GO) and mixtures thereof. In another embodiment, the fabric is impregnated in one of the following combinations of materials: PVDF, PVDF-GO 15%, PDMS or combinations thereof, where the percentages refer to the percentage by weight of the respective component on the total weight of the layer. In another embodiment, the combinations of materials that impregnate the fabrics of the high and low electronegativity layers are selected from the group consisting of the following combinations: PVA / PVDF-GO 15%, PVA-GO 1% / PVDF, PVA-GO 15% / PVDF-GO 15%, PVA-GO 100% / PVDF-GO 15%, PDMS (m) / PVA, PDMS / PVA-PANI, PDMS / PVA-PANI-GO 15%, PDMS / PVA-GO 100%, PVA+GMP 30% / PDMS. In another embodiment, at least one of the fabrics is additionally impregnated with metallic nanoparticles. In another embodiment, the sensors that collect the voltage pulses emitted by at least one triboelectric nanogenerator are metal sheets that wrap the layers of the triboelectric nanogenerator. In another embodiment, in the near field of frequencies below 3 GHz, the suit has a low shielding level that is less than 12 dB and a high shielding level that is greater than 20 dB. In another embodiment, in a non-near field of frequency between 3 and 40 GHz, the suit has a low shielding level that is less than 40 dB and a high shielding level that is greater than 60 dB. In another embodiment, when the triboelectric generator is composed of PDMS / PVA+gmp (30%), the suit has a high shielding level, and when it is composed of PVA-PANI-GO 15% / PVDF it has a low shielding level. In another embodiment, the metal sheets are made of Al or Cu, and allow for shielding that can reach more than 50 dB for all triboelectric nanogenerators and in near and far field for frequencies of 0.05-40 GHz. In another embodiment, the triboelectric nanogenerator covers one or more specific areas of the suit located near areas of the user's body that are to be monitored. In another embodiment, the triboelectric nanogenerator covers the entire suit. In another embodiment, the suit also comprises at least one flame-retardant material. In another embodiment, the flame retardant material is a phosphorus compound. In another embodiment, the suit comprises communication systems with signal acquisition, processing and / or communication systems, which are wireless and use Bluetooth, Wi-Fi or LoRA protocols. In another embodiment, the voltage pulses generated by friction between the layers have an amplitude and waveform that depend on the frequency, speed, acceleration, force, and relative displacement of these layers, allowing the calculation of the position and movement state of the suit's user or parts of it. In another embodiment, at least one triboelectric nanogenerator is configured to act as a signal trigger when pressure is applied, so that the user can send a warning signal by pressing it. In another embodiment, at least one triboelectric nanogenerator is configured to act as a temperature sensor by measuring the mechanical amplitude of the signal generated by friction between the layers of the triboelectric nanogenerator compared to the signal generated by another sensor that serves as a reference. And in another embodiment, the suit according to any of the preceding claims is a spacesuit, a suit for use in nuclear facilities, or a suit prepared for nuclear, biological and chemical (NBC) threats. The suits of the present invention include various types of sensors that collect the voltage pulses emitted by the friction of the electropositive and electronegative layers of the triboelectric nanogenerator. The amplitude and waveform of these pulses depend on the frequency, speed, acceleration, force, and displacement of these layers, and from this data, the user's movement patterns can be calculated. In preferred embodiments of the invention, these sensors are metallic sheets, which can be made of any metal, although preferably copper or aluminum, and which envelop the polymer layers of the triboelectric generator. These sheets also increase the shielding of both ionizing radiation (gamma, X-rays, neutrons, electrons, and protons) and non-ionizing radiation (radio waves or microwaves of the spectrum described above).From them come electrodes or thin cables that will go to the different acquisition systems or signal processing and communications chips. In one embodiment of the invention, any of the previously proposed material layers are used in such a way that the entire suit acts as a triboelectric generator: an electropositive layer is provided, which may be on the outer part of the suit, and an electronegative layer on the inner part, sandwiched along the entire length of the suit. In this way, the electropositive layers of different areas of the person's body, upon friction with the negative layers, will be monitored: the elbows (22) (23), legs (24) (25), feet (26) (27), helmet, etc. Their movement will produce voltage and current pulses. There may also be hard areas such as PDMS (-m), PVA (-m) (7), and variants, located on the chest (21), which will allow for the determination of any impacts or blows suffered by the user or astronaut. Preferred embodiment of the invention: First, the following materials with shielding and triboelectric generation properties have been produced: PVA / PVDF-GO 15%, PVA-GO 100% / PVDF, PVA-GO 100% / PVDF-GO15%, PVA-PANI-GO 15% / PVDF, PDMS (m) -PVA, PDMS / PVA-PANI, PDMS / PVA-PANI-GO 15%, PDMS / PVA-GO 100%, PVA+gmp (30%) / PDMS. In general, the more graphene, the more electromagnetic shielding. Next, PLA, nylon, or cotton fabrics were manufactured and impregnated with triboelectric compounds of the same charge. Another identical layer, but impregnated with compounds of the opposite charge, was manufactured in the same shape and adhered to the first. The fabrics thus constructed retain the triboelectric and shielding properties of the impregnated materials, thus acting as a shield against radiation from outer space or in environments with high levels of ionizing and non-ionizing electromagnetic and particle radiation, such as in operating nuclear power plants or accelerators. A suit shaped like an astronaut's spacesuit was designed using these fabrics. Electrodes, which can be a continuous layer of copper or aluminum or insulated sheets, were also attached to the outer layer of the fabric. Thin electrodes or wires of the same metal extend from these sheets and connect to the chips.These thin layers of metal (Al or Cu) also increase the electromagnetic shielding of graphene in the aforementioned radio wave regions of the spectrum. Metallic nanoparticles also contribute to this effect, similar to metallic sheets. Furthermore, graphene, as mentioned, and especially when used with metallic nanoparticles, is used for shielding much higher energies (gamma, neutron, and X-rays). Similarly, instead of nylon, it's possible to use more rigid polymers that form the triboelectric nanogenerators, which are rectangular or square in shape and placed in different areas of the suit. These are generally PDMS and PVA, either modified with nanohorns or unmodified. As with the triboelectric fabrics mentioned earlier, the electrodes will occupy the small areas (squares, rectangles, etc.) of the triboelectric generators' contact zones, which will be connected to the corresponding electronic and communication systems. The spacesuit can be used to monitor a person's movement, using fabric or rigid polymer sensors, as they move while walking or walking. The spacesuit may contain triboelectric generators, which are harder than the fabric and can act as triggers when pressure is applied, allowing the astronaut to send a warning signal by touching a part of the suit. Monitoring can be local or remote. For local monitoring, the astronaut or operator is connected by a cable to a monitor on their arm or one located on the spacecraft.Remotely, different communication protocols will be used: Bluetooth for monitoring at close range, such as to the spacesuit or the systems in the room where it is floating; Wi-Fi for longer distances to different areas of the spacecraft; and LoRa for communication between astronaut / spacecraft or astronaut / astronaut at distances of more than 200 km between transmitter and receiver (communication between users). A RAK (Rapid Access Kit) can also be used to upload all the information to the cloud. These suits can be used in other situations, such as when textiles are used as clothing outside of outer space, on Earth, in nuclear power plants or radioactive facilities where radiation protection is necessary. Protective fabrics can also be applied to robots operating in these facilities to ensure their electronics function in these extreme conditions. Similarly, they can be used in places where there is no harmful radiation, for monitoring people's movements (athletes, elderly people in hospitals, etc.). In this latter case, it may not be necessary to use graphene-based compounds. Depending on the user's movement, we will see different pulse generation due to the triboelectric effect. In the case of a PDMS / PVA+GO 1% (triboelectric generators C) (6) and (3), with slow movement (frequencies of 0.2 Hz), we observe long and wide pulses (27) whose height depends on the impact force on the material (600 N) and the material itself. Similarly, we can observe faster, more impact-driven pulses with higher amplitudes (28) with high-generation materials, such as the triboelectric generator F (layers (6) and (11)), due to the greater electrical generation efficiency when its layers come into friction or contact, and also depending on the applied tensile / compressive force (100 N). We observed other types of pulses for the same triboelectric generators C (29) with layers (6) and (3) but with a lower external force exerted between layers (400 N), although the same speed (70 mm / min).Similarly, other types of pulses appear for the same triboelectric generators F (30) with layers (6) and (11) but with a greater force (1000 N) and with the same speed (70 mm / min) and frequency, where impact is observed. The information in this paragraph refers particularly to soft materials that can be adapted to textiles. All these measurements allow us to obtain calibration curves, making the proposed suit a sensor for motion, speed, acceleration, force, or pressure. The Force vs. Voltage calibration curves vary depending on the material: thus, we have different calibration curves for different types of materials, such as PDMS / PVA-PANI-GO0.15% (30). It is observed that the PANI material has a higher electrical generation efficiency compared to the other textiles or soft materials, and that the forces are high because the materials are soft, suitable for blending with textiles. The tests were performed with a tensile-compression machine that has a 2 kN load cell. A 50 Hz low-pass filter was used.Furthermore, all triboelectric generators with graphene have the property of electromagnetic shielding and the calibration curves show a linear behavior, but generally with two different slopes for two different sections. The suit (9) operates as follows: the user / astronaut moves within their triboelectric suit. Their movement, via their legs (20) (22), feet (25) (26), and elbows (23) (24), is monitored online and locally on a PC (33). In the case of remote communication, this PC must be connected to the internet (via satellite if in space). In space, all chips are shielded from electromagnetic radiation (38). At most, the antenna of the communication devices will emit a signal externally and will be tightly sealed to prevent radiation from entering through the suit. The motion monitoring data will be transmitted via LoRA (31) over distances of hundreds of kilometers (in space) between transmitter and receiver, in the same way as to the cloud (37) using a RAK (32). Other protocols could be used like Wi-Fi, but their range is much shorter, although the amount of information is much greater.The signals can also be viewed locally on a watch, for example. In the case of a flow of radiation particles or electromagnetic radiation (35), the user will be protected by their suit (19), which shields this radiation (38). Similarly, if the user is in a fire (34) or experiences a significant temperature increase, the suit will protect them because it is fireproof and extinguishes the flame. The astronaut (or nuclear plant operator) will also be able to walk on a planet (36) and will be protected from cosmic radiation. Furthermore, they could press a button on their suit, which is a triboelectric generator (21), to send a warning signal. The triboelectric generator's signal would act as a "trigger" to initiate the instructions of the entire electronic and communications chain. The communications technologies to be used will be LoRa, for long-distance transmission and reception, and above all, low power consumption.For shorter distances and higher bandwidth, Wi-Fi, Zigbee, or Bluetooth, among others. It would also be possible to perform triangulation with LoRA transmitters and thus know the position of astronauts wearing suits at a great distance (200 km in outer space), although the error in the measurement would have to be taken into account. In addition to all this, phosphorus compounds can optionally be used as flame retardants to protect the astronaut or operator from radiation and high temperatures. These protective fabrics or coverings can also be used as a means of human-robot interaction. In this case, the person interacts with the robot, and the robot responds to the type of contact made: a tap, a sad face, a caress, a smile, etc. All of this depends on the signal generated by the fabric or a triboelectric generator integrated into the robot's casing. It's worth noting that, with this suit, the robot could operate in outer space. The material of the invention could also function as an alarm sensor in the event of a temperature rise or fire. In this case, the electrically generated signal would have a different mechanical amplitude than if there were no high temperature, alerting to an emerging fire or temperature increase due to a programmed voltage vs. temperature threshold known from a prior T vs. V calibration. Furthermore, the conductivity of the graphene-containing material (oxidized and reduced) would increase with temperature and humidity. Depending on the temperature of the suit and the mechanical impulse received, the temperature would be determined by the variation in the amplitude of the generated pulses and the pulses obtained from another sensor (piezoelectric, for example) that serves as a reference and responds differently to temperature. On the other hand, Deep Learning techniques will be used on the server or on an embedded board such as a Raspberry Pi or Pi 5. These techniques will allow us to determine, based on the frequency and amplitude of the pulses, along with their bandwidth, the physical quantities of velocity, acceleration, displacement, and force exerted. These physical quantities, such as frequency, velocity, acceleration, and displacement, can be analyzed with Deep Learning (DL) programs using multiple processing layers. In this way, through controlled environments of pulse amplitude and frequency, it is possible to classify and predict these quantities based on noise, baseline values, and pulses produced by the triboelectric layers used for chip protection. For each suit, fabric covering, or box manufactured, calibration curves can be generated with the selected materials. These curves will allow us to determine the calibrated physical magnitudes as a function of the generated pulse. Deep Learning (DL) algorithms can then be used with the pulses generated by the movement of the fabrics or the walls of the boxes, utilizing the same generated data. The majority of the initial data will be used to train the model, enabling the subsequent use of classification and prediction algorithms. The speed, acceleration, force, displacement, and frequency of the moving and monitored user can be determined from the waveform of the pulses generated by algorithms programmed using Machine Learning and Deep Learning. Similarly, vibrations experienced by more rigid coverings or boxes housing electronic and communication systems can also be analyzed. For the classification of physical quantities, Deep Learning can be used with different neural layers. This involves using datasets related to different frequencies (39), as well as datasets related to different amplitudes (40). Using statistical calculations with the results produced by Deep Learning, it is shown that, in a controlled frequency environment, it is possible to predict frequencies based on the pulse shape and baseline with virtually 100% accuracy. Therefore, in the case of an astronaut's suit or a typical user, we can determine the velocities, frequencies, forces, accelerations, and displacements that occur when they move. Regarding amplitude classification, very similar results are obtained in terms of accuracy, data loss, ROC cure, and confusion matrix. The suit doesn't need batteries to operate because it uses the triboelectric effect as its operating principle. The suit's electronics are powered by the astronaut's movement, which generates electrical energy and simultaneously detects that movement. The communications system will send pulses to a remote server or locally obtained information to that server. It will also send data to a watch or display worn by the astronaut in their spacesuit. References: [1] DDL Chung, "Materials for electromagnetic interference shielding," Mater. Chem. Phys., vol. 255, no. April, p. 123587, 2020, doi: 10.1016 / j.matchemphys.2020.123587. [2] P. Chandrasekhar and K. Naishadham, "Broadband microwave absorption and shielding properties of a poly (aniline), " Synth. Met., vol.105, no.2, pp.115-120, 1999, doi: 10.1016 / S0379-6779 (99) 00085-5. [3] S. K. Dhawan and D. C. Trivedi, "Thin conducting polypyrrole film on insulating surface and its applications, " Bull. Mater. Sci., vol.16, no.5, pp.371-380, 1993, doi: 10.1007 / BF02759550. [4] Y. K. Hong et al., "Electromagnetic interference shielding characteristics of fabric complexes coated with conductive polypyrrole and thermally evaporated Ag, " Curr. Appl. Phys., vol. 1, no. 6, pp. 439-442, 2001, doi: 10.1016 / S1567-1739 (01) 00054-2. [5] K. S. Kim et al., "Large-scale pattern growth of graphene films for stretchable transparent electrodes, " Nature, vol. 457, no. 7230, pp. 706-710, 2009, doi: 10.1038 / nature07719. [6] A. Yusuf, J. S. del Río, X. Ao, I. A. Olaizola, and D. Y. Wang, "Potential energyassisted coupling of phase change materials with triboelectric nanogenerator enabling a thermally triggered, smart, and self-powered IoT thermal and fire hazard sensor: Design, fabrication, and applications, " Nano Energy, vol. 103, 2022, doi: 10.1016 / j.nanoen.2022.107790. [7] J. S. del Río et al., "High-resolution TENGS for earthquakes ground motion detection, " Nano Energy, vol.102, 2022, doi: 10.1016 / j.nanoen.2022.107666. [8] X. Li, J. S. del Río Saez, X. Ao, A. Yusuf, and D. Y. Wang, "Highly-sensitive fire alarm system based on cellulose paper with low-temperature response and ireless signal conversion, " Chem. Eng. J., vol. 431, 2022, doi: 10.1016 / j.cej.2021.134108. [9] X. Li, J. S. del Río Saez, X. Ao, B. Xu, and D. Y. Wang, "Tailored P / Si-decorated graphene oxide-based fire sensor for sensitive detection at low-temperature via local and remote wireless transmission, " Constr. Build. Mater., vol.349, 2022, doi: 10.1016 / j.conbuildmat.2022.128600.

[10] X. Li, J. Sánchez del Río Sáez, S. Du, R. Sánchez Díaz, X. Ao, and D. Y. Wang, "Bio-based chitosan-based film as a bifunctional fire-warning and humidity sensor, " Int. J. Biol. Macromol., vol. 253, no. May, 2023, doi: 10.1016 / j.ijbiomac.2023.126466.

Claims

1. A protective suit for harsh environments, at least partially made of a fabric comprising at least one triboelectric nanogenerator composed of a high electronegativity layer having a charge density greater than 200 C / m² and a low electronegativity layer having a charge density less than 100 C / m², with the dynamically generated charge density for a pressure of 1.6 kPa between layers being less than 0.35 mC / m², wherein both layers are in contact and where the friction between the layers caused by the movement of the suit's wearer generates voltage pulses, characterized in that the suit further comprises sensors configured to collect the voltage pulses emitted by the triboelectric nanogenerator and send them to signal acquisition, processing, and / or communication systems. 2.Suit according to claim 1, wherein the triboelectric nanogenerator has an absolute charge density not exceeding 350 C / m2 in dynamic conditions and for a pressure of 1.6 kPa between layers less than 0.35 mC / m2.

3. Suit according to claim 1 or 2, wherein the low electronegativity layer comprises at least one fabric selected from the group consisting of nylon, cotton, PDMS, PLA or nanohorn-modified or unmodified PVA, which is impregnated in a material selected from polyvinyl alcohol (PVA), graphene (gmp), graphene oxide (GO) and PANI (8-aminopyren-1,3,6-trisulfonic acid (APS) + (3-aminopropyl) triethoxysilane) + aniline) and mixtures thereof.

4. Suit according to claim 3, wherein the fabric is impregnated with one of the following combinations of materials: PVA, PVA-gmp 30%, PVA-GO 100%, PVA-PANI GO 15% and PVA-PANI or combinations thereof, wherein the percentages indicated refer to the percentage by weight of the respective component relative to the weight of the garment. 5.Suit according to any of claims 1 to 4, wherein the high electronegativity layer with a charge density greater than 200 C / m² for a force greater than 1.6 kPa comprises at least one fabric selected from nylon, cotton, PDMS, PLA, or nanohorn-modified or unmodified PVA, impregnated with a material selected from polyvinylidene fluoride (PVDF), polydimethylsiloxane (PDMS), graphene oxide (GO), and mixtures thereof.

6. Suit according to claim 5, wherein the fabric is impregnated with one of the following combinations of materials: PVDF, PVDF-GO 15%, PDMS, or combinations thereof, wherein the percentages refer to the weight percentage of the respective component in the total weight of the layer. 7.Suit according to any one of claims 1 to 6, wherein the combinations of materials impregnating the fabrics of the high and low electronegativity layers are selected from the group consisting of the following combinations: • PVA / PVDF-GO 15%, • PVA-GO 1% / PVDF, • PVA-GO 15% / PVDF-GO 15%, • PVA-GO 100% / PVDF-GO 15%, • PDMS (m) / PVA, • PDMS / PVA-PANI, • PDMS / PVA-PANI-GO 15%, • PDMS / PVA-GO 100%, • PVA+GMP 30% / PDMS.

8. Suit according to any one of claims 2 to 7 above, wherein at least one of the fabrics is further impregnated with metallic nanoparticles.

9. Suit according to any of the preceding claims, wherein the sensors that collect the voltage pulses emitted by the at least one triboelectric nanogenerator are metallic sheets that envelop the layers of the triboelectric nanogenerator. 10.Suit according to any of claims 1-9 above, wherein, in the near field at frequencies below 3 GHz, the suit has a low shielding level of less than 12 dB and a high shielding level of more than 20 dB.

11. Suit according to any of claims 1-9 above, wherein, in the non-near field at frequencies between 3 and 40 GHz, the suit has a low shielding level of less than 40 dB and a high shielding level of more than 60 dB.

12. Suit according to any of claims 10-11, wherein, when the triboelectric generator is composed of PDMS / PVA+gmp (30%), the suit has a high shielding level, and when it is composed of PVA-PANI-GO 15% / PVDF, it has a low shielding level. 13.Suit according to any of claims 9-12, wherein the metal sheets are made of Al or Cu, and provide shielding that can reach more than 50 dB for all triboelectric nanogenerators in the near and far fields for frequencies of 0.05-40 GHz.

14. Suit according to any of the preceding claims, wherein the triboelectric nanogenerator covers one or more specific areas of the suit located near areas of the user's body that are to be monitored.

15. Suit according to any of claims 1 to 14, wherein the triboelectric nanogenerator covers the entire suit.

16. Suit according to any of the preceding claims further comprising at least one flame-retardant material.

17. Suit according to claim 17, wherein the flame-retardant material is a phosphor compound. 18.Suit according to any of the preceding claims comprising communication systems with signal acquisition, processing, and / or communication systems, which are wireless and use Bluetooth, Wi-Fi, or LoRa protocols.

19. Suit according to any of the preceding claims, wherein the voltage pulses generated by friction between the layers have an amplitude and waveform that depend on the frequency, speed, acceleration, force, and relative displacement of said layers, allowing the calculation of the position and movement status of the suit's wearer or parts thereof.

20. Suit according to any of the preceding claims, wherein at least one triboelectric nanogenerator is configured to act as a signal trigger when pressure is applied, so that the wearer can send a warning signal upon pressing it. 21.Suit according to any of the preceding claims, wherein at least one triboelectric nanogenerator is configured to act as a temperature sensor by measuring the mechanical amplitude of the signal generated by friction between the layers of the triboelectric nanogenerator compared to the signal generated by another sensor serving as a reference.

22. Suit according to any of the preceding claims that is a spacesuit, a suit for use in nuclear facilities, or a suit prepared for nuclear, biological, and chemical (NBC) threats.

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