CN110578249A

CN110578249A - Fiber profile for high fire protection requirements and method for producing same

Info

Publication number: CN110578249A
Application number: CN201810919019.4A
Authority: CN
Inventors: J·米勒
Original assignee: Individual
Current assignee: Individual
Priority date: 2018-06-07
Filing date: 2018-08-14
Publication date: 2019-12-17
Anticipated expiration: 2038-08-14
Also published as: DE102018113587B8; DE102018113587B4; CN110578249B; DE102018113587A1

Abstract

The invention relates to a fiber profile for high fire protection requirements, which can be used in particular for producing high-strength reinforcements for the construction industry. The object of the invention is to provide a fiber profile and a method for producing the same. The technical properties of the fiber profile should be significantly extended and optimized for new fire safety applications. In particular the surface of the fiber profile should be hardened and protected from damaging heat within a reasonable time. The fiber profile comprises fiber strands embedded in a matrix, which are made of a fiber composite material, in particular carbon fibers, basalt fibers and glass fibers. According to the invention, the fiber strands are surrounded by a matrix made of a metal silicate aqueous solution (water glass). The fiber profile may have a coating made of an alkali-resistant, highly heat-resistant sheet-like coating material applied to the substrate. As coating material sand and/or glass and/or mica sheets are used.

Description

Fiber profile for high fire protection requirements and method for producing same

Technical Field

The invention relates to a fiber profile for high fire protection requirements, which can be used, in particular, as a reinforcing profile for producing high-strength reinforcements for the construction industry. The fiber profiles are particularly suitable for use in concrete structures which have to meet high fire protection requirements, such as skyscrapers or bridges. The invention also relates to a method for producing a fiber profile which is produced during pultrusion from fiber strands embedded in a matrix, said fiber strands being produced from a fiber composite material, in particular from a carbon fiber, basalt fiber or glass fiber material.

Background

in the production of carbon fiber, glass fiber or basalt fiber strands, a plurality of individual fibers are usually combined and encapsulated in a matrix in one or more bundles. In the following, different fibre materials are named with the general term "fibre". The matrix serves to position and fix the fibers and also to protect them. In a known and practiced pultrusion process sequence, different coatings are applied on or locally into the direct surface of the substrate. In one known method, the coating process is carried out after the pultrusion process, partly using a certain residual viscosity of the matrix before its final age hardening or in the case of the application of a suitable, separate binder. This enables the creation of characteristics for specific application purposes. For example special surfaces or reinforcing strips for increasing the circumferential surface.

DE102014212241a1 describes carbon fibers, in particular for carbon fiber composite plastics (CFK). By means of this invention, it is proposed for the first time to apply a thin, hard plasma coating to the carbon fibers, which coating has amorphous siloxane. The carbon fibers thus obtain a surface that can be processed like the surface of glass fibers. The coating serves to better connect the carbon fibers with the encapsulating matrix.

DE102015119700a1 describes a method for adjusting the surface of carbon fiber profiles or carbon fiber surfaces pultruded and/or otherwise combined from carbon fibers by means of resins or adhesives, and a device for carrying out the method. The aim is to achieve a rough or fine structuring and thus a large surface without influencing the internal structure of the carbon fiber profile.

The carbon fibers are bundled in a manner known per se to form a continuous strand and embedded in a matrix made of a resin or a binder, where they are hardened. Before the hardening is completed, the surface is coated with a granular and/or round or fibrous and/or acicular coating material. As coating material, metal, glass and/or ultrafine sand are used, whereby a reinforcement that avoids wear and mechanical damage should also be possible. The surface coating is carried out with a granular and/or round or fibrous and/or acicular coating material.

WO2012/059540a1 describes a method for producing a pile layer made of disordered carbon fibers as bundles of surrounding carbon fibers. This method requires considerable technical and equipment expenditure.

WO2016/112898a1 describes a reinforcing rod made of a filament composite material and a method for its manufacture. The reinforcing rods should be able to withstand high temperatures. The reinforcing element is made of filaments embedded in a matrix material, which filaments are present prestressed or pretensioned in the direction of traction and are substantially completely surrounded by the mineral matrix material. Fine concrete or a suspension containing fine cement is used as the matrix material.

During the pultrusion process, individual fibers are coated by spreading the fiber bundles in a dispersion bath. During this process, the aqueous cement suspension penetrates between the spread fibers to encapsulate the individual strips. Since carbon fibers are hydrophobic, it is difficult to form high quality coatings in this way, especially because such highly ground cements tend to have extremely short setting reactions. It is well known that process control of the controlled setting process of cement slurries is difficult. Cement releases much heat and is easily burned. The strength of the crystal structure that determines the strength and is naturally grown by the cement slurry is very incompletely formed. But its formation is critical for acceptable adhesion on and between the individual fiber structures. The mechanical strength of the thin layer thus produced is not very high empirically.

With the methods known and practiced at present for producing carbon fibers, basalt fibers and glass fibers as concrete reinforcements, fire protection which can effectively withstand mechanical loads cannot be achieved. Although basalt fibers and glass fibers are inherently non-flammable, the matrix connecting the fibers is flammable or can change at high temperatures such that it no longer meets the regulatory protection functions.

Disclosure of Invention

The object of the invention is to provide a fiber profile for high fire protection requirements and a method for producing the same. The fiber profiles should be suitable in particular in the form of high-strength profiles as reinforcing materials for concrete structures. The technical properties of the fiber profile can be significantly expanded and optimized for new fire safety applications. In particular the surface of the fiber profile should be hardened and protected from damaging heat within a reasonable time.

According to the invention, this object is achieved by the features of the device claim 1 and the method claim 5. The expansion features are described in the dependent claims 2 to 4 and 6 to 10.

Fiber profiles for high fire protection requirements comprise fiber strands embedded in a matrix, which are made of fiber composite materials, in particular carbon fibers, basalt fibers and glass fibers. According to the invention, the fiber strands are surrounded by a matrix made of an aqueous metal silicate solution (water glass, silica). Technically feasible amorphous aqueous solutions of alkali metal silicates, such as sodium silicate, potassium silicate, lithium silicate, can be used.

the ph of the reaction medium is in the alkaline range. The viscosity of the matrix can vary within wide limits. The matrix can thus be adjusted between a thin liquid state for penetration between the fiber strands and a thick liquid state for enveloping the fiber bundles. The infiltration and the subsequent encapsulating coating can be carried out in separate successive steps with the aid of the respectively defined matrix. Despite a somewhat greater expenditure on equipment, this solution is suitable for large-scale applications due to correspondingly good viscosity-independent adjustability.

For still higher fire protection requirements, the fiber profile can have a coating with coating particles made of an alkali-resistant, highly heat-resistant sheet-like coating material applied to the substrate. Preferably, the coating is carried out during the pultrusion process while the suitable matrix still has viscosity or residual viscosity. The coating process can be repeated multiple times. Mica flakes of defined dimensions and flat, granular quartz sand, for example in the form of a discus, are used as materials for the coating in accordance with regulations. Round alkali-resistant flat cullet is also suitable. The mica or glass particles preferably have a size of up to 0.5mm, and the flat granular quartz sand particles have a size of 0.06 to 0.2 mm.

For effective fire protection, at least 95% of the surface should be coated with the foil.

A coarser grain size may also be chosen for the use of the fiber strands as reinforcement in concrete. For example, a first layer of fine particles and a second, coarser layer may be provided as described above. The material is preferably agitated by hot air in the space surrounding the pultruded strip. The gas flow can advantageously be moved in a circular vortex in the cylindrical space. The coating quality can be controlled by adjusting the mixing ratio between air and coating material.

For special applications, the fiber profile can have a coating made of sand and/or glass and/or mica sheets embedded in epoxy resin.

Mica, glass and fine sand can be coated alternately for several times according to the protection requirements. For this purpose, an adhesive or matrix is arranged between the layers to be applied.

Mica, glass and flat granular quartz sand are poor thermal conductors. The mica sheet is extremely reflective of thermal radiation with its particularly smooth surface. In multilayer coatings (i.e., multiple layers of mica or glass applied with a binder or matrix therebetween), a scaly fiber strand surface is created. In another embodiment, the flat granular quartz particles and mica platelets may be alternately applied layer by layer through a binder or/and a matrix.

In a method for producing fiber profiles for high fire protection requirements, fiber strands are embedded in a matrix during pultrusion and subsequently hardened. The fiber strands are impregnated into a matrix made of an aqueous metal silicate solution (water glass).

The matrix surrounding the fiber profile can be coated with an alkali-resistant and highly heat-resistant coating material, which is preferably configured in the form of a sheet. Thereby covering large surfaces and providing fire protection.

The matrix surrounding the fiber profile can be coated with a coating material embedded in an epoxy resin. As coating material, mainly sand and/or glass and/or mica sheets are used.

Drawings

The present invention is illustrated in detail by the following examples. The attached drawings are as follows:

FIG. 1 is a schematic illustration of a pultrusion process having two matrix vessels containing matrices of different viscosities;

FIG. 2 is a schematic illustration of a pultrusion process having a substrate vessel, an additional coating apparatus and subsequent drying apparatus;

FIG. 3 is a fiber profile having a solid mineral coating on a silica substrate;

FIG. 4 is a fiber profile with a solid mineral coating on a second matrix layer of silica;

FIG. 5 is a fiber profile with a solid mineral coating directly on the silica matrix (the interstices between the fibers are filled with a silica matrix in the dilute liquid state and form a common envelope of the strip);

Fig. 6 is a fiber profile with a double-sided coating, with a planar arrangement of parallel extending fibers.

Detailed Description

Fig. 1 and 2 show a first exemplary embodiment for producing a fiber profile for high fire protection requirements. They show a schematic view of a pultrusion process according to the invention with two matrix vessels containing matrices of different viscosities. Exemplary fiber profiles as end products are shown in fig. 3, 4 and 5.

The raw material is subjected to the following steps:

1. A fibre sliver 2 made of carbon fibre is unwound from a supply reel 1 with the desired number of fibre slivers. For ease of illustration, fig. 1 shows only 3 reserve reels 1. In practice, the finished fiber profile 20 includes a plurality of individual fiber strands.

2. The individual fiber strands 2 are collected by means of rollers 3 and suitable conventional guides known per se into a fiber bundle 4 until a defined thickness 20 of the desired fiber profile 20 is reached.

3. The fiber bundle 4 thus produced is guided without prestress through a matrix container 5 which is filled with an aqueous metal silicate solution (water glass) of a predetermined viscosity as a liquid matrix 5. Here, the solution may be heated and/or under pressure. This facilitates the process of completely surrounding all the fiber strands 2 with the relatively liquid matrix 7. The non-prestressed path 8 allows the gaps between the individual fiber strands 2 to be easily filled with the liquid matrix 7. The consumed substrate 7 is periodically replenished by means of a substrate supply 6. The viscosity of the matrix 7 is selected such that it penetrates into the interstices of the individual fiber strands 2 at high speed. The fiber strand 2 passes through the matrix container 5 in this case without stress. The substrate container 5 may advantageously be pressurized. In which matrix container the matrix 7 is sucked in between the individual fiber strands 2 by capillary forces. The pressure in the substrate container 5 accelerates the process. It is also advantageous if the fiber strand 2 and the matrix 7 are heated.

4. The fiber bundles 4 exiting from the matrix container 5 are conveyed further by means of a conveying device 9. The conveying device can have a heating device, by means of which the fiber bundle 4 can be heated by hot air or hot CO₂The gas is flowed around to assist the gelling process of the matrix, thereby forming a gel and thus initiating the hardening process.

5. The fiber bundle 4 then enters a second matrix container 10, which contains a metal silicate in the form of a thick liquid with a predetermined viscosity dissolved in aqueous silicic acid. In this case, the envelope layer of the fiber bundles 4 is produced as intended. The main fire protection is applied to this still viscous layer. The substrate 12 is more viscous than the substrate 7 and has a gel-like consistency, which is also heated and under pressure if necessary. This path 13 with defined prestress allows the individual fiber strands 2 in the fiber strand 4 to already adhere to one another and the fiber strand 4 thus produced to be entirely enveloped at its circumferential surface. Visually this is similar to the outer insulation of the cable. The consumed substrate 12 is periodically replenished by the substrate supply means 11.

6. The fiber strand 4 emerging from the matrix container 10 is conveyed further by a further conveying device 9. The conveying device can also have a heating device, by means of which the fiber bundle 4 is heated by hot air or hot CO₂The gas flows around toAssisting the gelling process of the matrix.

An additional process is shown in fig. 2. The production of the fiber bundles 4 by means of the liquid matrix 7 is shown in fig. 2 only in a single stage. This is also possible in principle, but it is necessary to adjust the consistency of the matrix 7 used additionally or to variably adjust the heat or ventilation conditions.

7. In a subsequent coating vessel 16, the coating is carried out with alkali-resistant and highly heat-resistant coating particles 17. In a preferred application, mica platelets of defined size are supplied from the outside through the particle supply means 18. The mica sheets are agitated in the coating vessel 16 by the directed air movement. The moving coating particles 17 adhere to the still viscous matrix surface 25 of the matrix 23 enclosing the fiber bundles 4. Excess coating particles 24 may exit the coating vessel through the discharge opening 19. The final coating process, i.e. thick matrix gel plus coating, can be repeated. The fire protection is enhanced with each additional coating.

8. The coated fiber profile 20 emerging from the coating container 16 is subjected to heat radiation 14 or hot air or hot CO in a drying and curing container 22₂Gas is flowed around to aid in the gelling and hardening process of the matrix.

9. The conveyor 21 conveys the coated fiber profile 20 to the cutting device 15, in which the fiber profile 20 is cut to the desired length.

Fig. 3 shows a fiber profile 20 in cross section, which has a solid mineral coating on the substrate surface 25 of the substrate 23 enclosing the fiber strand 2. The substrate 23 is made of an aqueous metal silicate solution (trade name: water glass).

Fig. 4 shows a fiber profile 20 for achieving a particularly high fire safety. In this case, an outer substrate layer 26 is subsequently applied to the inner substrate 23 directly enveloping the fiber strand 2 and is coated alternatively or additionally with solid mineral coating particles. Mica platelets are still chosen here as coating particles 24. The outer second matrix layer 26 is preferably a gel-like water glass solution in a thick liquid state or an epoxy resin. The gaps between the fiber strands 2 are filled with a matrix of a silica salt solution (water glass) in a dilute liquid form as the inner matrix 23. Since the second outer substrate layer 26 is embedded in or on the inner substrate coating in a form-fitting manner in part or in its entirety in the event of a fire, it can be considered as a sacrificial layer and can preferably only be used where appropriate. In particular the outer epoxy layer acts as a sacrificial layer in case of fire.

Mica is a naturally occurring layered silicate which is characterized by a distinct plate-like structure and exists in different mica types. The mica is characterized by its plate-like particles, high aspect ratio (1:30), and density of about 2.85g/cm³Its hardness of about 2.5(Mohs) and low oil absorption and its resistance to high temperatures.

fig. 5 shows a fiber profile 20 which has a solid mineral coating directly on an inner matrix 23 made of silicon salt, the interstices between the individual fiber strands 2 being filled with a silicon salt matrix in the form of a liquid and forming a joint encapsulation of the fiber bundles 4. Thin glass sheets are used as coating material 24 here, for example.

Fig. 6 shows a fiber profile with a double-sided coating, which has a planar arrangement of parallel fiber strands 2. Between the plurality of fiber strands 2 (only two of which are shown here), an inner matrix 23 is provided, which has an outer matrix layer 26, on which coating particles 24 are embedded. The fiber profiles are used, for example, as fabrics and scrims made of carbon fibers, basalt fibers or glass fibers, which are provided on both sides with a coating as a flameproof protective covering.

The invention extends the production processes known and practiced to date in such a way that the components acting in particular for the static state exert the possible fire protection required for many applications in the construction industry.

for this purpose, a fire protection is first applied to the fiber profile, which protection reflects thermal radiation. For exceptionally high and highest fire protection requirements, epoxy resins can additionally be used as binders (known as thermal protection in space navigation) which are used in accordance with regulations for connecting mica platelets to pultruded fiber strands or to one another.

As a statically active reinforcing material, the fiber profile is better protected by the coating against the effects of heat, for example, which occur in the event of a fire in a building. The so-called failure of the reinforcement caused by uncontrolled thermal action is significantly delayed.

List of reference numerals

1 reserve reel

2 fiber strip

3 roller

4 fiber bundle

5 substrate container

6 substrate supply device

7 matrix

8 road section without prestress

9 conveying device

10 matrix container

11 substrate supply device

12 matrix

13 has a defined prestress

14 heat radiation

15 cutting device

16 coating container

17 coating particles

18 particle supply device

19 discharge port

20 fiber section bar

21 conveying device

22 drying and age hardening apparatus

23 internal matrix

24 coated particle

25 surface of the substrate

26 outer matrix layer

Claims

1. Fiber profile for high fire protection requirements, comprising fiber strands made of a fiber composite material embedded in a matrix, characterized in that the fiber strands (2) are surrounded by a matrix (23) made of a metal silicate aqueous solution (water glass).

2. fiber profile according to claim 1, characterized in that the fiber profile (20) has a coating with coating particles (24) made of an alkali-resistant, highly heat-resistant sheet-like coating material applied to a substrate (23).

3. A fibre profile according to claim 2, wherein the coating material is sand and/or glass and/or mica.

4. Fiber profile according to one of claims 1 to 3, characterized in that the fiber profile (20) has a coating with coating particles (24) made of sand flakes and/or glass flakes and/or mica flakes embedded in epoxy resin.

5. Method for producing a fibre profile for high fire protection requirements, wherein fibre strands (2) are embedded in a matrix (7) during pultrusion and subsequently hardened, characterized in that the fibre strands (2) are impregnated into a matrix (7) made of an aqueous metal silicate solution.

6. Method according to claim 5, characterized in that the matrix (7) surrounding the fiber profile (20) is coated with coating particles (17) made of an alkali-and heat-resistant coating material.

7. Method according to claims 5 and 6, characterized in that the matrix (23) surrounding the fiber profile (20) is coated with coating particles (17) made of a sheet-like coating material.

8. Method according to one of claims 5 to 7, characterized in that the matrix (23) surrounding the fiber profile (20) is coated with coating particles (24) made of a coating material embedded in an outer matrix layer (26), such as epoxy resin.

9. Method according to one of claims 5 to 8, characterized in that sand and/or glass and/or mica sheets are used as coating material.

10. Method according to one of claims 6 to 9, characterized in that the coating comprises more than 95% of the surface of the fiber profile (20).