RU2803465C2 - Fibrous products coated from aqueous polymer dispersions - Google Patents

Abstract

FIELD: fibrous materials.

SUBSTANCE: invention is related to a composite fibrous material made from a textile fibre product having a coating containing from 5 wt.% up to 100 wt.% of the applied material, based on the total weight of the fibrous product, and the material contains from 20 to 100 wt.% polymers based on ethylene polymerizable monomers having a glass transition temperature from 60 to 115°C, from 0 to 80 wt.% of cross-linking components and from 0 to 20 wt.% of other additives in a cement-bound matrix, where the polymers are derived from a monomeric composition, and the monomeric composition contains from 5% to 100% basic monomers A, from 0% to 50% functional monomers B and from 0% to 30% cross-linking monomers C, respectively, based on the total weight of the monomeric composition, with the main monomers A selected from the group of C1-C24 alkyl(meth)acrylates. The use of the fibrous product for cement-bonded materials is also described.

EFFECT: provision of a textile-concrete composite with an extraction resistance value in concrete comparable to textile-concrete composites coated with epoxy textile reinforcement.

13 cl, 3 tbl, 1 dwg, 1 ex

Description

The present invention relates to coated textile fiber products containing polymers based on ethylene polymerizable monomers having a glass transition temperature of at least 60°, and to a coating method for coating the fibrous products with an aqueous polymer dispersion, in which the aqueous polymer dispersion is first coated with an aqueous polymer dispersion based on ethylene, in particular vinyl, polymerizable monomers having a glass transition temperature of at least 60°C, then brought into contact with the fibrous product, followed by drying.

The invention further relates to the use of corresponding polymer dispersions for coating fibrous products, to corresponding coated fibrous products, to their use for reinforcing mineral matrices and to corresponding fibrous composite materials, especially textile-concrete composite materials. In particular, the invention relates to a coating agent that can be applied to a textile sheet in a continuous water-based process, providing optimal force dissipation from the mineral matrix into the textile reinforcement.

Steel reinforced concrete has become indispensable in the modern construction industry. It offers high reliability at an affordable price. The disadvantage of this material is the tendency of reinforcing steel to corrosion. In the 1990s, fiber-reinforced concrete also became an alternative to steel-reinforced concrete. In this case, mostly steel or plastic fibers are mixed with concrete. These fibers are not oriented within the matrix. The approach of using oriented fibers in the form of reinforcement structures is relatively new: fundamental research has been conducted on this textile-reinforced concrete composite material for almost 20 years.

Textile-reinforced concrete uses continuous fibers (filaments), such as glass, basalt and carbon, in the form of two- or three-dimensional textile sheets or steric structures. In principle, suitable fibers include those having high strength and high stiffness, or having a modulus of elasticity comparable to that of steel, such as alkali-resistant glass fibers or carbon fibers. Technical textile materials can be tailored to the stress they experience using the geometry of non-woven scrims. Variable distances between threads in non-woven canvases lead to a specific grain composition of concrete. It has a smaller maximum grain diameter compared to conventional cements. Therefore, fine-grained concrete is used in combination with textile reinforcement. The spacing of the carbon fiber threads in the canvas is important to the size of the components. The reduced grain size improves the permeability of the canvas, and stable composites between multiple layers of textile concrete can be realized.

The use of textile reinforcements allows some interesting improvements to be achieved in terms of processing as well as properties of composites. The biggest advantage is that there is no additional coating of the concrete as protection against corrosion, as is usual in reinforced concrete. In textile reinforced concrete, the thickness of the concrete layer is determined, in addition to the properties of the concrete, only by the geometry and strength of the yarns and fiber composites used to provide the minimum load requirements for the composite. In this way, the overall thickness of the component can be reduced to approximately a quarter of the mortar thickness of the reinforced concrete component, and material savings of up to 80% have been reported. This allows for easier design and implementation of forms and applications that have been considered impossible with incompressible reinforcement systems to date, since components can be made thinner while maintaining the same stability.

Textile reinforcement structures are more effective in improving composite properties if they are presented in the form of geometric structures. They have found commercial application as reinforcement elements in concrete elements or as reinforcement structures in the field of building maintenance. Because the requirements for textile reinforcement structures are varied, a wide variety of fiber types are used. The range includes inorganic fibers such as carbon, glass and basalt fibers, as well as organic fibers from aramid, polyethylene or polypropylene. Already today, textile reinforced concrete structures have many interesting applications, for example for later reinforcement and maintenance of buildings or as façade elements.

WO 2004/007161 A1 describes the use of textile reinforced concrete structures for the reinforcement of concrete sewer pipes. Reinforcement of road surfaces made of asphalt and concrete is known from US 6632309 B1. The preparation of ready-mixed concrete parts is disclosed in EP 2894272 A2 as well as in WO 2014/106685 A1.

To produce textile reinforcing structures, filamentary fibers of a certain size are usually first processed into yarn or rovings (tow, multifilament yarn, similar to DIN 60 001 part 2) of several thousand threads and knitted. They are subsequently processed by textile processes into reinforcing textiles with specific geometries. After processing, these fabrics are impregnated with a polymer material. This absorption/covering possibly includes all the individual threads and thus provides an internal bond between the fibers or roving and a bond between the edge fibers and the concrete, the so-called external bond. In addition, the coating causes stabilization of the shape of the meshes and ensures the geometric accuracy of the reinforcement. This process step can be carried out, on the one hand, in the form of an intermittent textile process by impregnation and curing with a reactive resin. These processes use, for example, epoxy resins or unsaturated polyester resins. On the other hand, the composite textile can be impregnated with a coating agent during a continuous textile coating process, such as padding.

Today, for example, carboxylated styrene-butadiene copolymers (so-called X-SBR) are used in such processes. After impregnation, the coated sheets undergo drying and curing stages. Composite textiles prepared in this way can be used as draped rolled products for maintenance applications or as sheet rolled products in new construction or finished construction parts, depending on the properties of the textile geometry and the coating used. The corresponding composite material is obtained by appropriately incorporating these textile sheets into the matrix material. When concrete or cement-like and/or mineral matrix materials are used as matrix materials, the composites are referred to as concrete components or textile reinforced structures.

Textiles used as reinforcement in concrete have the function of carrying external loads, especially tensile forces, through the concrete interface. Inside the composite structure, i.e. especially within each individual roving, such tensile forces must be transferred to the individual threads. Full utilization of the fiber properties is only possible by impregnating the roving with a suitable material and allows for significantly higher achievable tensile strength values (>40%) compared to unimpregnated roving. In this composite material, the coating agent has the function of providing optimal bonding of the composite from the concrete matrix to the composite textile. The covering polymer material is therefore of key importance in terms of the properties of the entire component: it ensures optimal force application both at the concrete/composite textile interface and between the respective individual roving fibers in the composite textile.

The performance of a composite material such as textile reinforced concrete is determined by the transfer of force at said interfaces. In particular, this means that these properties must be maintained under the required environmental conditions and throughout the entire service life of the component. Thus, the textile is exposed to temperature conditions during outdoor use, for example from 30°C to +100°C, must withstand the alkaline solution in the pores of the concrete or also be resistant to salt depending on the application. This leads to high requirements for the selection of coating materials.

In the field of reinforcement, the commercial product TUDALIT® (Z-31.10-182) has a general construction permit developed by the German Bautechnik in der Bundesrepublik Deutschland (abZ). It describes an aqueous coating material based on a dispersion of carboxylated styrene-butadiene copolymer (so-called X-SBR), which is cross-linked with melamine-formaldehyde resins. The systems thus obtained exhibit sufficient resistance to the alkaline environment of the solution in the pores of concrete and have a moderate level of yarn tensile strength, close to 1700 N/mm ² . Additionally, a binder system can be applied through a continuous impregnation and/or casting process, and the fabricated meshes can be wound onto rolled products due to their property profile and tailored to the required geometry by bending/converting on site within certain limits. However, it may be mentioned that the processing time (processing time) is very narrow, due to the use of a reactive melamine/formaldehyde cross-linker, which greatly limits the practical applicability of this system. In addition, the disadvantage is that the strength of composites that can be achieved with this system requires long anchorage lengths. In addition, the composite properties measured in a textile reinforced concrete component are very dependent on temperature: due to the low glass transition temperature of X-SBR, its use in exterior applications is not possible, and accordingly, approval was only granted for the interior area and for temperatures up to 40°C. A similar system is used in DE 102005048190 A1.

In addition, the use of aqueous polymer dispersions as a coating for textile reinforcement in concrete is described in EP 2004712 B1. Here, an aqueous polychloroprene dispersion is used in combination with inorganic particles for fiber reinforced concrete. The production of rigid textiles is achieved by the crystallinity of the polychloroprene coating after film formation or drying. However, truly relevant improvements in mechanical properties in a composite are only achieved by adding inorganic particles to the same coating. In addition, AR glass fibers were coated with polyacrylate dispersions as early as 2001 in order to test them for use in textile-reinforced concrete components (doctoral dissertation by M. Schleser "Einsatz polymerimprägnierter, alkaliresistenter Glastextilien zur Bewehrung zementgebundener Matrices", Aachener Berichte) Fügetechnik, vol. 06/ 2008, editor: Prof. Dr. Ing. U. Reisgen, November 1, 2008, Shaker Verlag). However, only polymers with a glass transition temperature clearly below 60°C were used, and the properties of the components at higher application temperatures were not studied.

For use in the higher temperature range, curable reactive resin systems, especially epoxy resins, are used as polymer matrix materials in textile reinforced materials. Such systems are described, for example, in DE102008040919 A1 and EP2530217 B1. The composite materials mentioned here consist of reinforcing textiles made from industrial fibers such as glass, carbon, basalt or aramid, bonded to cementitious systems. Reinforcing structures of high rigidity and strength are obtained using epoxy resins. The tensile strengths that can be achieved with carbon fibers are close to 3500 N/mm ² . Bond strength, anchorage length and resistance to alkaline mineral matrix in cement bonded systems are described as good. These systems maintain the properties of the joint at temperatures up to 100°C, making it suitable for outdoor applications. However, reinforcing textiles coated with a reactive resin, especially epoxy resin, can only be produced periodically, and due to their rigidity they can no longer be wound onto rolls or wound around existing geometric shapes.

Additionally, these reactive resins, especially epoxy resins, have short processing times, typically below 90 minutes. The composite properties in the concrete component and the temperature dependence of the composite properties are well studied and have been published within the special research areas 528 and 532 of the Deutsche Forschungsgemeinschaft (DFG) (e.g. Manfred Kerbach, Regine Ortlepp (Eds.) SFB 528 Textile Bewehrungen zur bautechnischen Verstärkung und Instandsetzung, Final report - abridged version - for the period 2008/2-2011/1). In any case, the use of reactive resin systems to impregnate textile reinforcement for concrete structures is state of the art. This is also described in EP2666922 B1, in which plastic-reinforced rovings, such as long glass fibers impregnated with epoxy resin and dried at 80°C (so-called prepregs), are used as reinforcement structures. Lightweight concrete reinforcing elements made from resin-impregnated fibrous materials are also described in EP 0227207 B1; here, in addition to epoxy resins, virtually all commercially available reactive resin systems are used. US Pat. No. 4,910,076 A combines two different approaches and a network of fibers impregnated with a reactive resin (polyurethane or epoxy) is subsequently coated with a self-crosslinking SBR dispersion.

When curable reactive resins, such as epoxy resins, are used as polymeric coating materials, meshes are obtained that have high levels of tensile strength of up to 3500 N/mm ² of carbon fiber yarn and high alkali resistance. In addition, the composite properties in textile-concrete composites are thermally stable up to 100°C. However, the disadvantage is that continuous application of impregnating material is not possible in these systems due to limited processing time. In addition, only rigid grids that do not drape can be produced, and therefore it is not possible to prepare rollable reinforcing textiles from which easily transportable roll products can be produced. Another disadvantage is the health risk of processing epoxies and amines on a large scale.

Although an alternative coating agent based on carboxylated styrene-butadiene copolymers produces rollable and draped reinforcement fabrics, which in principle can be further produced in a continuous process, the resulting reinforcement fabrics exhibit a low tensile strength of 1700 N/mm ² of carbon fiber yarn. In addition, to achieve sufficient composite properties in textile-concrete composite, long fastening lengths are required, which is mainly a disadvantage with regard to the size and design of building components. Additionally, composite properties can only be achieved at temperatures up to 40°C with this coating system, which is a significant limitation for commercial applications, especially outdoors.

According to the prior art, coating systems based on polychloroprene dispersions provide sufficiently good composite properties only in combination with inorganic substances. The properties relating to heat resistance and alkali resistance are not substantiated by examples.

Therefore, compared with the described prior art, the object of the present invention is to provide a polymeric coating agent that can be applied to a fibrous product in a continuous water-based process and ensures optimal application of force from the mineral matrix to the textile reinforcement. Suitable coated textile reinforcement structures must be suitable for use in cement-like matrices and be capable of being wound onto rollers (roller diameter from 20 cm). In particular, the tensile strength of 48K carbon fiber rovings impregnated with the coating agent according to the invention should be in the temperature range from -30 to +100°C and in the range above 3000 MPa. In addition, the composite properties of the coated reinforced structure in the textile-concrete composite should be maintained from -30°C to +100°C, and there should be sufficient resistance to alkaline environments in cement-like or mineral-bound matrices.

In a first embodiment, the object of the invention is achieved by using a textile fiber product having a coating containing from 5 to 100 wt. % of material applied, based on the total weight of the fibrous product, wherein the material contains

from 20 to 100 wt. % polymers based on ethylene polymerizable monomers having a glass transition temperature of at least 60°C,

from 0 to 80 wt. % cross-linking components; And

from 0 to 20% by weight of other additives.

Preferably, the coating contains from 10 to 60 wt. % of applied material.

Preferably, the polymerizable monomers are vinyl polymerizable.

In a preferred embodiment, the polymers can be prepared from a monomer composition, wherein said monomer composition contains from 5 to 100% basic monomers A, from 0 to 50% functional monomers B and from 0 to 30% cross-linking monomers C, respectively, based on the total the mass of the composition of monomers, where, in particular, the main monomers A are selected from the group of vinyl aromatic monomers and C ₁ -C ₂₄ alkyl (meth) acrylates, specifically, the functional monomers B are selected from the group of (meth)acrylic acid, C ₂ -C ₈ hydroxyalkyl ( meth) acrylates, C ₂ -C ₈ (alkyl)aminoalkyl(meth)acrylates, sulfonated monomers, phosphated monomers and vinyl pyridines, specifically the C cross-linking monomers contain at least two ethylenically unsaturated non-conjugated groups, N-methylol groups and/or epoxy groups.

Preferably, the cross-linking components contain monomers C and/or external cross-linkers having reactivity with functional monomers B, especially those selected from the group of di-, tri- and/or polyfunctional unblocked or blocked isocyanates, epoxysilanes, formaldehyde resins, melamine resins, carbodiimides and epoxy resins. These components react with other coating components and undergo cross-linking.

The fibrous product according to the invention preferably contains one-dimensional textile structures, two-dimensional textile sheets and/or three-dimensional textile steric structures.

Preferably, the fibrous product of the invention contains, or consists of, carbon fibers, glass fibers, basalt fibers, aramid fibers, polyethylene fibers and/or polypropylene fibers, including mixtures thereof.

In an alternative embodiment, the object of the invention is achieved by a method of coating fibrous articles with an aqueous polymer dispersion, especially to produce fibrous articles of the invention, comprising

i) providing an aqueous polymer dispersion that contains a polymer based on ethylene, especially vinyl, polymerizable monomers having a glass transition temperature of at least 60° C., and optionally a suitable material for cross-linking the polymer;

ii) bringing the fibrous article into contact with said aqueous polymer dispersion; And

iii) drying the thus coated fibrous product, specifically at room temperature or at elevated temperature up to 220°C.

The prior art to date has used almost exclusively SBR and polychloroprene types to coat fiber products with aqueous polymer dispersions, based on the argument that they have high stability in alkaline environments. It has now unexpectedly been found within the scope of the present invention that certain polymer dispersions, for example based on (meth)acrylic monomers and/or styrene monomers, also have sufficiently high alkali resistance. Surprisingly, aqueous polymer dispersions having a glass transition temperature of at least 60° C. based on vinyl polymerizable monomers, optionally in combination with external crosslinkers, are well suited for coating fibrous products for use in textile concrete composite systems that have the above properties.

Preferably, the glass transition temperature of the polymers in the dispersion used is at least 70°C.

In a preferred embodiment of the method according to the invention, one-dimensional textile structures, two-dimensional textile sheets and/or three-dimensional textile steric structures are used as the fibrous product.

Suitable one-dimensional textile structures include, for example, but are not limited to yarns, rovings, threads and/or ropes. Suitable substantially two-dimensional textile sheets include, for example, nonwoven meshes, woven fabrics, loop-pattern knitted fabrics, loop-patterned knitted fabrics, stitched fabrics, non-woven fabrics, and/or felts, but are not limited to.

In a preferred embodiment of the method according to the invention, said fiber product includes carbon fibers, glass fibers, basalt fibers, aramid fibers, polyethylene fibers and/or polypropylene fibers. In particular, the fibrous product consists of fibers from one of these types of fibers or mixtures thereof.

Said bringing into contact of the aqueous polymer dispersion and the fibrous article according to the invention can be carried out by any method known in the art. Preferably, the fibrous article is brought into contact with the aqueous polymer dispersion using a continuous or intermittent textile application method of the prior art. In particular, preferred application methods include soaking, fine spraying, dipping, casting and/or jet spraying, but the invention is not limited to such methods. The applied mass of material thus obtained, based on the total mass of the fibrous product, ranges from 5 to 100 wt. %, preferably from 10 to 60 wt. %, more preferably from 25 to 50 wt. %, even more preferably from 30 to 40 wt. %.

In a preferred embodiment of the method according to the invention, the proportions of the components of said aqueous polymer dispersion are selected so as to obtain a solids content of from 10 to 70 wt. %, more preferably from 25 to 60 wt. %., even more preferably, from 40 to 50 wt. % based on the total weight of the polymer dispersion. The proportion of solid particles of the dispersion preferably contains from 20 to 100 wt. % polymer, from 0 to 80 wt. % crosslinking agent and from 0 to 20 wt. % of other additives based on the proportion of solid particles of the dispersion, percentages add up to 100%.

In addition to the main components described, the aqueous dispersion according to the invention may further contain additional auxiliaries and additives known in the construction, textile and coating industries, including, but not limited to, leveling auxiliaries, wetting agents, defoamers, defoamers, organic and inorganic thickeners, resin tackifiers, fillers, pH adjusters and/or preservatives.

In a preferred embodiment of the method according to the invention, the aqueous polymer dispersion based on vinyl polymerizable monomers is provided by suitable continuous, semi-continuous or discontinuous polymerization processes known in the art. Particularly preferred are emulsion polymerization, suspension polymerization or dispersion polymerization. Even more preferably, the polymer dispersion is produced by emulsion polymerization, which is technically justified and described many times (Hans-Georg Elias, Makromoleküle, volume 3, "Industrielle Polymere und Synthesen", 6th edition, Wiley-VCH). The polymer dispersion can be stabilized with surfactants commonly used in the prior art, such as anionic surfactants, nonionic surfactants and/or protective colloids and mixtures thereof, without limiting the invention. Any suitable type of initiator may be used to initiate the polymerization reaction, including, but not limited to, peroxides, azo compounds, and/or redox initiator systems. In addition, reagents that are commonly used in such a process may be used, including, but not limited to, electrolytes, pH adjusting agents, and/or chain regulators/transfer agents.

In a preferred embodiment of the invention, the aqueous polymer dispersion is provided by polymerization of a monomer composition containing from 5 to 100 wt. % main monomers A, from 0 to 50 wt. % functional monomers B and from 0 to 30 wt. % crosslinking monomers C, respectively, based on the total weight of the monomer composition.

Suitable basic monomers A include, in particular, C ₁ -C ₂₄ alkyl esters of acrylic and methacrylic acids, as well as vinyl aromatic monomers such as styrene, methyl styrene or vinyl pyridine. These monomers can be used alone or in any mixture thereof such that the glass transition temperature of the resulting polymer is at least 60°C. The latter can be estimated from the glass transition temperatures of the monomers to be used using the Fox equation (TG. Fox, Bull. Am. Phys. Soc. 1, 123 (1956)) or the Pochan equation (JM. Pochan, CL. Beatty, D .F. Hinman, Macromolecules 11, 1156 (1977)), as is known to one skilled in the art.

In particular, the following monomers having a reactive group can be used alone or in mixture as functional monomers B: (meth)acrylic acid, C ₂ -C ₈ hydroxyalkyl (meth)acrylates such as hydroxyethyl methacrylate, C ₂ -C ₈ (alkyl)aminoalkyl (meth)acrylates such as dimethylaminoethyl methacrylate, sulfonated monomers such as sodium styrene sulfonate, phosphated monomers such as monoacryloxyethyl phosphate, and/or vinyl pyridines. The invention is not limited to the functional monomers mentioned. Any suitable functional monomer in the prior art may be used. Suitable monomers are those in which the glass transition temperature of the resulting polymer is at least 60°C.

Monomers containing at least two ethylenically unsaturated non-conjugated groups, N-methylol groups and/or epoxy groups are preferably used as cross-linking monomers C. Suitable monomers include divinyl and polyvinyl monomers such as divinylbenzene, di- or poly(meth) )acrylates, di- or polyallyl ethers and di- or polyvinyl ethers of diols or polyols. In addition, monomers can be used that can still cross-link after the soaking process and form a coating without the need to add an external cross-linking agent such as N-methylolacrylamide and/or glycidyl methacrylate.

In addition, an external cross-linking agent can be added to the aqueous polymer dispersion prepared in accordance with the invention to improve the mechanical properties of the coated fiber products and the compositional properties of the resulting textile-concrete composites. Preferably, it has a reactivity that matches the reactivity of the functional groups present in the polymer dispersion. For example, but not limited to, blocked and unblocked polyisocyanates, carbodiimides, aziridines, epoxy resins, epoxysilanes, formaldehyde resins, urea resins, reactive phenolic resins, without limitation, can be used. Their application in a coating system is accomplished by mixing the polymer dispersion and the external cross-linking agent immediately before bringing the fibrous product into contact with the aqueous polymer dispersion.

In an alternative embodiment, the object of the invention is achieved by using a coated fibrous article produced by a coating method according to the invention. Preferably, the fibrous product in accordance with the invention can be obtained using one of the preferred embodiments of the method in accordance with the invention. Preferred embodiments of the method steps and reagents used may also be combined.

The coated fiber products of the invention have excellent tensile strength and bond strength in concrete and can thus be used as concrete reinforcement with particular advantage. Thus, carbon fibers coated in accordance with the invention exhibit comparable levels of tensile strength and concrete extraction strength as a prior art epoxy resin system (see Table 1, entry 2, compared to Table 3, entry 1 -5). Thus, the use of such fibrous products is not exclusive, but is particularly advantageous for reinforcing concrete and/or cement products. Other coated fiber products of the invention can be used to reinforce existing concrete structures that are used outdoors (eg, façade slabs or other exterior structures) and are exposed to temperatures or weather conditions up to 100°C.

The coating according to the invention based on said aqueous polymer dispersion is also of great interest for use on hydrolytically sensitive fibrous materials such as glass or basalt fibers. From the measured values shown in Tables 3, items 6 and 7, it is clear that good tensile strength values of the coated rovings are achieved at room temperature and at 100°C. They clearly exceed the values achieved by coating with polymer dispersions not in accordance with the invention (Table 2, items 6 and 7). According to the manufacturer, the glass fiber used in the examples passes class II of the so-called SiC test (Strength of Concrete, EN 14649). In these tests, glass fibers are embedded in concrete and stored at 80°C and 80% relative humidity for 96 hours. In the subsequent test, the residual strength to provide Class II must be at least 350 MPa for an initial strength of 1000 MPa, i.e. the reduction can be a maximum of 65%. If this glass fiber is coated in accordance with the invention (see Table 3, item 6), a significant increase in alkali resistance is achieved, since the reduction in strength is only 35%. With basalt fibers coated according to the invention (Table 3, item 7), the reduction is 60%.

This shows that the aqueous polymer dispersion obtained in accordance with the invention surprisingly has good alkali resistance and is therefore excellent for use as a textile reinforcement coating for cement-bonded matrices. Table 3 shows the extraction resistance values of carbon fibers coated according to the invention in concrete (positions 1-5) at room temperature and at 80°C. In both cases, excellent values are achieved, which are on par with epoxy-coated fibers according to the prior art. Table 3 also shows the corresponding values for alkali-resistant glass fiber (AR glass) (item 6). These values are significantly higher than, for example, the values specified in patent EP2004712 B1.

Fiber products made from carbon fibers and coated according to the invention have also been found to be suitable for winding onto a 20 cm diameter roller in the processing direction of 12k roving.

In another embodiment, the object of the invention is achieved by using an aqueous polymer dispersion, as provided in the above-described method according to the invention, as a coating agent for fibrous products. The aqueous polymer dispersion used may have all the advantageous features of the polymer dispersion used in the method according to the invention. Use according to the invention makes it possible to obtain fibrous products according to the invention with the described advantages.

In another embodiment, the object of the invention is achieved by using a composite material comprising a coated fibrous article according to the invention and a mineral matrix, specifically a concrete matrix. More preferably, the composite material is made from a fibrous product according to the invention in a mineral matrix, specifically a concrete matrix. In particular, the composite material according to the invention is a textile-concrete composite with the above-described advantages of the invention. In particular, the composite material contains a fibrous article according to the invention in the form of a one-dimensional textile structure, a two-dimensional textile sheet and/or a three-dimensional textile steric structure.

In another embodiment, the object of the invention is achieved by using coated fibrous products according to the invention, especially in the form of one-dimensional textile structures, two-dimensional textile sheets and/or three-dimensional textile steric structures for the reinforcement of mineral materials, especially for the reinforcement of concrete elements. Use in accordance with the invention makes it possible to provide composite materials in accordance with the invention with the technical advantages described above.

Examples

Using the method according to the invention, coated fibrous products and corresponding textile and concrete composite materials obtained from them are obtained. To do this, polymer dispersions according to the invention were first applied to 3200tex type carbon fibers from TohoTenax by soaking followed by drying at 160°C. From the fibrous products obtained in accordance with the invention, samples were prepared to determine the tensile strength at room temperature (RT), at 100°C, and after storage in alkali (see characterization methods/tensile testing). In addition, textile-concrete composite materials were prepared by embedding fiber products coated according to the invention into fine-grained concrete (test sample, see FIG. 1) and subjected to extraction test (see characterization methods/extraction test).

In the same way, Examples with glass and basalt fibers were carried out, as well as Comparative Examples with polymer dispersions not corresponding to the invention and polymers from the prior art.

The following measurements were carried out: Tensile tests with coated rovings at room temperature RT, at 100°C, and after storage in an alkaline environment (ETAG004), tests by extraction method with textile-concrete composites at room temperature RT and at 80°C. Table 1 shows the results of these tests for examples of the prior art. Table 2 shows the test values obtained for samples not prepared in accordance with the invention. Table 3 summarizes the corresponding test values for samples prepared in accordance with the invention.

Next, the materials used and the results of the tensile and extraction tests are described in more detail.

Materials used :

Rovings/yarn :

- carbon fiber type 3200tex from TohoTenax

- basalt fiber type 2400tex from Deutsche Basalt Faser GmbH

- alkali-resistant glass fiber type 2400tex from Owens Corning

Fine-grained concrete :

115 g of water and 1 kg of Pagel TF 10 fine concrete made from Portland cement were loaded into a planetary mixer and mixed for 5 minutes (according to the technical data sheet of the concrete used).

Polymer dispersions :

Commercially available products can be used as polymer dispersions. In the examples given, model polymers were prepared using the classical semi-continuous emulsion polymerization method. All polymer dispersions have a solid content of 47 wt. %. In order to obtain polymers having a high glass transition temperature of 60° C. or more, according to the invention, monomer compositions were selected having a high proportion of monomers that lead to solid polymers, for example styrene. Accordingly, polymers not according to the invention contained higher proportions of soft comonomers, for example, ethylhexyl acrylate. The exact composition for a specific glass transition temperature was calculated using the Fox equation and confirmed by post-synthesis DSC measurements. The amount applied to the fibers used was approximately 30 wt. % for all aqueous binder dispersions used.

The epoxy resin system components are based on a commercially available cycloaliphatic epoxy with a cycloaliphatic amine as the hardener. The system did not contain solvent or water. The amount of coating applied was about 50 wt. % solids on fiber after drying.

Crosslinking agents :

Crosslinker 1: Blocked polyisocyanate from Covestro

Crosslinker 2: Reactive polyisocyanate from Covestro

Methods for obtaining characteristics

Yarn coating

Yarns made from carbon, glass or basalt fibers can be used as finishing yarn. The yarn is covered or impregnated by hand. During coating, from 10 to 60 wt. is applied to the fiber. % polymer. The yarn thus coated is then dried at 160°C.

Tensile test

DIN EN ISO 527-4 and DIN EN ISO 527-5 are standards for fiber reinforced materials (FRM) valid in Europe. Two standards cover only FRM tensile testing. This test measures the stress/strain behavior at the 0° and 90° fiber orientation limit states to determine properties such as Poisson's ratio v, tensile strength σM, elongation at break εM, and modulus of elasticity.

In plastics testing, the tensile test has priority and is considered the basic experiment under quasi-static or static test conditions. In accordance with DIN EN ISO 527-4, the crosshead is launched at a constant speed. FRMs typically exhibit rigid and brittle behavior. Therefore, the tensile strength σM and the yield strength σY are the same. The breaking stress σB can occur at the same point. Test specimen type 1B from DIN EN ISO 527-4 is mainly used for fiber-reinforced thermoplastics and thermosets. The test sample used is oriented towards it.

The materials are tested under three conditions: at room temperature, at 100°C and after storage in an alkaline environment. For the final test, samples were stored at 45°C in a pH 13.7 solution for 14 days and tested at 45°C without pre-drying. The test solution is based on the solution in the composition described in ETAG004.

Test by extraction method

In the general building permit of the German Institute for Construction Technology in Germany (abZ) No. Z-31.10-182 describes testing the adhesion strength of textiles to fine-grained concrete. In this test, a textile reinforced test specimen is loaded. The force is introduced by clamping on the top and bottom sides of the test piece. The textile reinforcement is oriented in the load direction in the test specimen (0° with the load direction). The maximum force of the machine F _max is used for evaluation. To characterize the strand samples, a method similar to that described above is used. It is also described elsewhere (current RILEM Technical Committee Report TC 201-TRC; EP2004712 B1) to characterize the bond strength between yarn and textile. The coated strands were immersed in concrete with dimensions width x thickness = 5 cm x 6 cm with a concrete thickness of 1 cm halfway, as shown in Fig. 1. A 0.5 cm concrete cover was used similar to abZ No. Z-31.10-182. The coated strands were prepared with an overhang of 1.5 cm beyond the concrete in the extraction direction to ensure that the bonding area on the concrete always remained the same during testing. Test conditions were chosen similar to abZ No. Z-31.10-182. The test speed is from 1 mm/min to 3 mm of extraction length and 5 mm/min from 3 mm of extraction length to completion of extraction. Test samples are measured at room temperature and at 80°C. The maximum extraction force _Fmax is estimated.

Table 1 - References to prior art

Fiber type Chemical structure ¹ T _g [°С] Polymer functionality Internal stapler External stapler Tensile strength RT [MPa] Tensile strength 100°C [MPa] Tensile strength ETAG004 [MPa] ⁴ Extraction force F _max RT
[H] Extraction force F _max 80°C [N] 1 ² carbon SBR -10 carboxy - melamine resin 2500 2400 2400 ^4* 660 180 2 ³ carbon E.P. 100 - - - 3500 2700 3300 > 1500 ⁵ > 1500 ^{5 1} SBR=styrene butadiene rubber, EP=epoxy resin
² aqueous SBR dispersion Lefasol VL 90/1 (Lefatex)
³ cycloaliphatic epoxide, cured with cycloaliphatic amine, T _g =100°C
⁴ tensile strength at 45°C after storage in a solution in the pores of concrete, pH 13.7, for 14 days without drying
^4* tensile strength at room temperature for coated roving after storage in a solution in the pores of concrete (pH 12.8) for 7 days with drying
⁵ concrete cracked along the load during testing due to too high adhesive strength

Table 2 - Examples not in accordance with the invention

Fiber type Chemical structure ¹ T _g [°C] Polymer functionality Internal stapler External stapler Tensile strength RT [MPa] Tensile strength 100 °C [MPa] Tensile strength
ETAG0
04 [MPa] ³ Extraction force F _max RT [N] Extraction force F _max 80 °C [N] 1 carbon ACR 10 - - - 2900 2200 2800 520 78 2 carbon ACR 40 - - - 3700 2400 2900 580 170 3 carbon ACR 5 Hydroxy - - 3100 2400 2800 800 410 4 carbon ACR 5 Hydroxy - stapler 1 2900 2500 3100 680 340 5 carbon ACR 8 - PETA ² - 2600 2000 2200 700 280 6 AR glass ACR 5 Hydroxy - stapler 1 950 560 580 660 360 7 basalt ACR 5 Hydroxy - stapler 1 990 930 360 220 96 ¹ ACR=pure acrylate, SAC=styrene acrylate
² PETA=pentaerythritol triacrylate
³ tensile strength at 45ºC after storage in a solution in the pores of concrete, pH 13.7, for 14 days without drying

Table 3 - Examples in accordance with the invention

Fiber type Chemical structure ¹ T _g [ºC] Functionality polymer Internal stapler External stapler Tensile strength RT [MPa] Tensile strength 100ºС [MPa] Tensile strength ETAG004 [MPa] ³ Extraction force F _max RT [N] Extraction force F_max
80ºС [N] 1 Carbon ACR 70 - - - 3900 2700 3200 940 930 2 Carbon S.A.C. eleven
⁵ - - - 3300 2800 2900 1000 1000 3 Carbon S.A.C. 10
⁵ Hydroxy - - 3500 3000 3400 > 1500 ⁴ > 1500 ⁴ 4 Carbon S.A.C. 10
⁵ Hydroxy - Stitcher ² 3900 3000 3600 > 1500 ⁴ > 1500 ⁴ 5 Carbon ACR 10
⁵ - PETA
² - 3200 2900 3100 > 1500 ⁴ > 1500 ⁴ 6 AR glass S.A.C. 15 Hydroxy - Stitcher ² 910 790 590 910 760 7 Basalt S.A.C. 10
⁵ Hydroxy - stapler ² 1100 1100 430 1000 1000 ¹ ACR=pure acrylate, SAC=styrene acrylate
² PETA - pentaerythritol triacrylorite
³ tensile strength at 45ºC after storage in a solution in the pores of concrete, pH 13.7, for 14 days without drying
⁴ concrete cracked along the load during testing due to too high bond strength

Claims (25)

1. A composite material made of a textile fibrous product having a coating containing from 5 wt. % up to 100 wt. % of material applied, based on the total weight of the fibrous product, the material containing: from 20 to 100 wt. % polymers based on ethylene polymerizable monomers having a glass transition temperature from 60 to 115°C, from 0 to 80 wt. % cross-linking components; And from 0 to 20 wt. % other additives, in a cement-bonded matrix, characterized in that the polymers are derived from a monomer composition, wherein the monomer composition contains from 5% to 100% basic monomers A, from 0% to 50% functional monomers B and from 0% to 30% cross-linking monomers C, respectively, based on the total weight of the monomer composition, and the main monomers A are selected from the group of C1-C24 alkyl (meth)acrylates. 2. Composite material according to claim 1, characterized in that textile fibrous product is a textile fibrous product with a coating containing from 10 to 60 wt. % of applied material. 3. Composite material according to claim 1 or 2, characterized in that the functional monomers B are selected from the group of (meth)acrylic acid, C2-C8 hydroxyalkyl (meth)acrylates, C2-C8 (alkyl)aminoalkyl (meth)acrylates, sulfonated monomers, phosphate monomers and vinyl pyridines, the C cross-linking monomers contain at least two ethylenically unsaturated non-conjugated groups, N-methylol groups and/or epoxy groups. 4. Composite material according to any one of claims 1 to 3, characterized in that the cross-linking components contain monomers C and/or external cross-linking agents having reactivity towards functional monomers B, preferably selected from the group of two-, three- and/or multifunctional unblocked or blocked isocyanates, epoxysilanes, formaldehyde resins, melamine resins, carbodiimides and epoxy resins. 5. Composite material according to any one of claims 1 to 4, characterized in that the textile fibrous product contains one-dimensional textile structures, two-dimensional textile sheets and/or three-dimensional textile spatial structures. 6. A composite material according to any one of claims 1 to 5, characterized in that the textile fibrous product contains or consists of carbon fibers, glass fibers, basalt fibers, aramid fibers, polyethylene fibers and/or polypropylene fibers, and mixtures thereof. 7. A composite material according to any one of claims 1 to 6, characterized in that the textile fibrous product is produced by a method for producing a textile fibrous product, including i) providing an aqueous polymer dispersion that contains a polymer based on ethylene polymerizable monomers, preferably vinyl polymerizable monomers, having a glass transition temperature of from 60 to 115° C., and optionally a suitable material for cross-linking the polymer; ii) bringing the fibrous article into contact with an aqueous polymer dispersion; And iii) drying the thus coated fibrous product, preferably at room temperature or at an elevated temperature of up to 220°C. 8. The composite material according to claim 7, characterized in that the method includes bringing the fibrous article into contact with an aqueous dispersion of the polymer by using a continuous or intermittent textile application method, preferably impregnation, fine spraying, dipping, casting and/or jet spraying. 9. A composite material according to claim 7 or 8, characterized in that said method includes the use of an aqueous polymer dispersion with a solids content in the range of 10 to 70%, specifically in the range of 25 to 60%, based on the total weight of the dispersion polymer. 10. A composite material according to any one of claims 7 to 9, characterized in that the method includes producing an aqueous polymer dispersion by continuous, semi-continuous or discontinuous polymerization, preferably by emulsion polymerization, suspension polymerization or dispersion polymerization. 11. Composite material according to any one of claims 1 to 10, characterized in that the matrix is a concrete matrix. 12. The use of a fibrous product for reinforcing cement-bound materials, wherein the fibrous material is a textile fibrous product having a coating containing from 5 wt. % up to 100 wt. % of material applied, based on the total weight of the fibrous product, the material containing: from 20 to 100 wt. % polymers based on ethylene polymerizable monomers having a glass transition temperature from 60 to 115°C, from 0 to 80 wt. % cross-linking components; And from 0 to 20 wt. % other additives, characterized in that the polymers are derived from a monomer composition, wherein the monomer composition contains from 5% to 100% basic monomers A, from 0% to 50% functional monomers B and from 0% to 30% cross-linking monomers C, respectively, based on total weight of the monomer composition, and the main monomers A are selected from the group of C1-C24 alkyl (meth)acrylates. 13. Use according to claim 12, wherein the cement-bonded materials are concrete components.

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