Carbon fiber conductive coiled material

Abstract

The present invention relates to the field of construction, i.e. Roofing materials, which can be used in the construction of roofs and other similar building structures with waterproof coatings made of asphalt, asphalt polymer or polymer materials in order to check the tightness or continuity (integrity) of shaped waterproof coatings made of dielectric materials by electrospark. The technical effect obtained by implementing the invention is that the strength characteristic of the conductive coiled material which is used as an isolating layer of a dielectric waterproof coating and a conductive substrate in a building structure is improved. An electrically conductive web for use as an electrically conductive substrate within roof structures and other similar building structures is presented. The invention relates to a composite material comprising a web, the composition of which comprises additionally introduced carbon fibers and a synthetic binder, the substrate of which comprises glass fibers, the synthetic binder ensuring that the glass fibers and carbon fibers are bonded into a single block, and wherein the mixture used to make the material comprises 95.1-99.9 wt.% of glass fibers and 0.1-4.9 wt.% of carbon fibers.

Description

[0001] The utility model relates to the field of construction, namely, roofing materials, which can be used for the construction of roofs and other similar building structures with waterproof coatings made of asphalt materials, asphalt polymer materials or polymer materials, so as to facilitate the inspection of the tightness or continuity (integrity) of the formed waterproof coating made of dielectric materials by the electric spark method.

[0002] Russian Federation invention patent No. 2720344 with a priority date of August 29, 2019 discloses a conditionally conductive substrate for diagnosing waterproof tightness. Conditionally conductive substrate refers to any substrate of material modified to be used as a conductive layer. Laths and monolithic materials with a humidity greater than 7%, or a specific electrical resistance less than 10 5 The insulation material and the roll material of Ω·m can be used as a conditionally conductive substrate. The lath and the monolithic material can be a cement bonded particle board characterized by a moisture content greater than 7%. In particular, the insulation material and the roll material can be a composite material based on glass fiber or glass wool.

[0003] Russian Federation Utility Model Patent No. 201323, with a priority date of September 29, 2020, discloses a conductive substrate. The known conductive substrate is made of a foil-coated hydrophobic material consisting of spunbond (non-woven fabric) and aluminum.

[0004] A disadvantage of the known analogues is their short durability due to the use of metals in the conductive layer of the material, these metals being characterized by relatively poor resistance to aggressive media.

[0005] The carbon fiber conductive coil in the Russian Federation Utility Model Patent No. 207852 with a priority date of May 11, 2021 was selected as a prototype, which contains glass fibers (substrate) and additionally introduces carbon fibers and a synthetic binder, which ensures that the glass fibers and the fibers are bonded into a single block. In this case, the mixture used to make the material contains 70-95wt.% of glass fibers and 5-30wt.% of carbon fibers. The disadvantage of the known conductive coils containing carbon 35 fibers is that their strength properties are reduced. For example, for materials containing 80wt.% and 20wt.% of glass fibers and carbon fibers, respectively, the tensile strength of the substrate does not exceed 300N / 50mm.

[0006] The technical task of the utility model is to expand the scope of conductive materials and make them suitable for the surfaces of roofs and other similar building structures to check the tightness or continuity (integrity) of a formed waterproof coating made of dielectric materials by an electric spark method.

[0007] The technical effect achieved by implementing the utility model is to improve the strength characteristics of the conductive coiled material used as the isolation layer of the dielectric waterproof coating and the conductive substrate in the building structure.

[0008] An additional technical effect is improved durability of the conductive web due to an increase in the tensile load required to break the conductive web used as a conductive substrate in building structures.

[0009] The utility model claims protection for a conductive coiled material used as a conductive substrate in roof structures and other similar building structures. The composition of the coiled material comprises additionally introduced carbon fibers and a synthetic binder, the substrate of the coiled material comprises glass fibers, the synthetic binder ensures that the glass fibers and the fibers are bonded into a single block, wherein the mixture used to make the material comprises 95.1-99.9wt.% of glass fibers and 0.1-4.9wt.% of carbon fibers.

[0010] The synthetic binder mainly comprises resin, polymer dispersion and demineralized water.

[0011] Conductive coils with glass fiber and carbon fiber content in the specified range have a density of 85 to 125 g / m 2 , whose resistance does not exceed 10 4 Ω·m, and the tensile strength of the substrate ranges from 350 to 400N / 50mm.

[0012] The conductive web is manufactured by a wet process or papermaking technique, i.e. a mixture consisting of glass fibers (95.1-99.9 wt.%) and carbon fibers (0.1-4.9 wt.%) is continuously dispersed in a "white water" solution (demineralized water, thickener, dispersant and defoamer) in an amount sufficient to open the glass fibers, i.e. not leaving initial glass fiber rods (crushed material) and not forming glass fiber lumps), and the resulting solution is fed to a steel forming net up to 5 meters wide. Once the mixture of glass fibers and uniformly distributed carbon fibers on the forming net or bonding net is dehydrated, a synthetic binder containing the following main components is added to the mixture: resin, polymer dispersion and demineralized water. The impregnated mixture is then moved through furnaces with different temperatures and convection modes. These operations lead to the formation of a reference conductive web with carbon fibers, which is characterized by a density ranging from 85 to 125 g / m 2 And the specific resistance is less than 10 4 Ω·m.

[0013] The use of the material described herein for the reference layer in a flat roof allows instrumental diagnosis of the waterproof seal by instrumental methods of non-destructive testing (i.e. the electric spark method) and eliminates the risk of losing the material's conductive properties in the aggressive alkaline medium typical of roofs.

[0014] Compared to conductive substrates known in the prior art, the conductive coils described herein are more resistant to acidic and alkaline media, are not subject to the damaging effects of corrosion, mold and rot, low (down to -55°C) and high (up to +120°C) temperatures, and have improved tensile strength properties due to their more uniform structure compared to conductive coils with higher (5 wt.% and more) carbon fiber contents.

[0015] The manufacture of this type of conductive coil is cheaper than the manufacture of composite materials with a conductive layer made of foil (copper, aluminum or other metals). There is no continuous metal layer on the surface of the coil described herein, which ensures the vapor permeability of the coil, preventing rot and mildew and any type of corrosion. At the same time, the technology for manufacturing the material described herein is much simpler. Therefore, the cost of the coil described herein is lower than that of the foil-coated coil. At the same time, since no metal is used, the durability of the material described herein is significantly longer, and the metal has a lower resistance to aggressive media than the coil described herein obtained by introducing carbon fibers into the structure of glass fiber mats during the manufacturing stage. This makes the carbon fibers randomly but evenly distributed in the volume of the coil, ensuring the conductivity of the coil.

[0016] The prepared carbon fibers and glass fibers (a few centimeters long pieces) are continuously mixed in a disperser in an appropriate ratio of (0.1-4.9) / (95.1-99.9) wt.%, obtaining a mixture based on a "white water" solution (demineralized water, thickener, dispersant and defoamer). When the mixture is fed to a forming or bonding web up to 5 meters wide, it is impregnated with a synthetic binder consisting of resin, polymer dispersion and demineralized water. The impregnated mixture on the web is fed to continuous ovens with different temperatures and convection modes, which correspond to the selected composition of the mixture. Once the coil is dry, it is rewound and, if necessary, cut into narrower rolls.

[0017] Once the coil is dry, the carbon fibers evenly distributed throughout its structure form a conductive grid, ensuring the coil's electrical conductivity.

[0018] The coil described herein is intended to be used as a conductive substrate for roof structures and other similar building structures, on top of which a dielectric waterproof material is laid and connected to form a waterproof coating. During the inspection of the waterproof coating, spark breakdown between the conductive coil connected to the spark detector and the flaw detection probe occurs at the defect of the waterproof coating.

[0019] The feasibility of the utility model is demonstrated by the following embodiments.

[0020] Example 1 Glass fiber and carbon fiber scraps are mixed in a ratio of 95.1 / 4.9wt.% with softened water to which a thickener, a dispersant and a defoaming agent are added. The resulting mixture is dispersed using an ultrasonic disperser and then supplied to a forming net up to 4 meters wide, where the mixture is dehydrated. The mixture moving on the bonding net is then impregnated with a synthetic adhesive, and the excess adhesive flows through the screen and returns to the next part of the mixture. The mixture impregnated with the synthetic adhesive is subjected to a series of heat treatment operations in a furnace at a temperature range of 60°C to 130°C. These operations result in the formation of a conductive coil with carbon fibers, which is characterized by a density ranging from 85 to 105 g / m 2 And the specific resistance is less than 10 4 Ω·m, and the tensile strength of the substrate is 350N / 50mm.

[0021] Without the addition of carbon fibers, the web (eg, fiberglass mat) is dielectric.

[0022] Example 2 Glass fiber and carbon fiber scraps are mixed in a ratio of 99.9 / 0.1wt.% with softened water to which a thickener, a dispersant and a defoaming agent are added. The resulting mixture is dispersed using an ultrasonic disperser and then supplied to a forming net up to 2 meters wide, where the mixture is dehydrated. The mixture moving on the bonding net is then impregnated with a synthetic adhesive, and the excess adhesive flows through the screen and returns to the next part of the mixture. The mixture impregnated with the synthetic adhesive is subjected to a series of heat treatment operations in a furnace at a temperature range of 60°C to 130°C. These operations result in the formation of a conductive coil with carbon fibers, which is characterized by a density ranging from 100 to 120 g / m 2 And the specific resistance is less than 10 4 Ω·m, and the tensile strength of the substrate is 400N / 50mm.

[0023] Without the addition of carbon fibers, the web (eg, fiberglass mat) is dielectric.

Claims

1. A conductive coiled material used as a conductive substrate in a roof structure, characterized in that The composition of the roll comprises additionally introduced carbon fibers and a synthetic binder, the base of the roll comprises glass fibers, the synthetic binder ensures that the glass fibers and the fibers are bonded into a single mass, wherein the mixture used to make the material comprises 95.1-99.9 wt. % of glass fibers and 0.1-4.9 wt. % of carbon fibers.

2. The conductive coil according to claim 1, characterized in that: The synthetic binder mainly comprises resin, polymer dispersion and demineralized water.