DE102008020906A1 - Layer on a substrate comprises polymer matrix and particles embedded in the matrix, where the particles comprise particles with layer lattice structure, and the concentration of particles is higher at the top of layer than at the bottom - Google Patents

Abstract

Layer (101) on a substrate (100) comprises polymer matrix and particles, which are embedded in the matrix, where: the lower side of the layer is located in adjacent to the substrate base and upper side of the layer is turned away from the substrate; the particles comprise particles with a layer lattice structure (102), and the concentration of particles with a layer lattice structure in the matrix is higher at the top of the layer than at the bottom. Independent claims are included for: (1) a process for coating a substrate, preferably for the production of the layer, comprising forming a first coating layer on a substrate by applying a first composition comprising at least a organosilicon polymer precursor, and forming a second layer on the first layer by applying a second composition comprising at least an organosilicon polymer precursor, where the first composition comprises the plate-shaped particles and/or corrosion inhibitors and/or the second composition comprises hard material particles and/or particles with layer lattice structure; (2) a coating composition (i), preferably for producing the first layer comprising 1-25 wt.% of the plate-shaped particles, 1-25 wt.% of corrosion inhibitors and the organosilicon polymer precursors; (3) a coating composition (ii), preferably for producing the second layer, comprising 1-25 wt.% of particle with layer lattice structure, and an organosilicon polymer precursor; (4) a kit for producing the layer or for use in the process for coating a substrate, comprising the coating composition (i) and (ii); and (5) a substrate exhibiting the layer.

Description

The The present invention relates to a layer which is a protective coating suitable for facilities in power plants and industry, Coating compositions useful in making such a layer suitable and substrates having such a layer.

In reactors and incinerators, for example in coal or lignite power plants, and in particular in waste incineration plants and biomass power plants, facilities such as heat exchangers, superheater pipes, tubes in econimisers and fin walls, steel pipes, steel tube aggregates, waste heat boilers, electrostatic precipitators, air preheaters and steam / gas preheaters (DaGaVos) are at high temperatures and attack by corrosive gases and especially by entrained by the gases corrosive solids exposed. So z. As the flue gas stream of normal urban waste very reactive components such as HCl, H ₂ S, SO ₂ or Cl ₂ and volatile reactive salts such as NaCl, KCl, CaCl ₂ , Na ₂ SO ₄ and PbCl ₂ . Similar problems relate Biomasseanla conditions in which wood waste of different quality or other vegetable fuels such as straw, corn spindles, nut or rice husks, etc. are burned. In particular, industrial steels such. For example, boiler steels ST35, ST37, ST38.8, 15Mo3, 10CrMo910, and 13CrMo44, which are commonly used in incinerators for waste, biomass, coal, and industrial waste, can be severely damaged.

Farther Problems can arise from that the corrosive solids and ashes entrained by the gases to be firmly attached to the said facilities. such Deposits can, for example, the heat transfer from a combustion chamber to a heat exchanger inhibit, reduce continue the life of the steel surfaces and need be removed on a regular basis, either during operation, for example by means of water lances or so-called sootblower, or in the event of plant downtime, then in particular by mechanical removal by means of sandblasting, brushing, by means of a jackhammer or even by controlled Demolition.

To the Protection of said industrial steels against corrosion it is known the steel surfaces with metals such as aluminum, Silicon, nickel and chromium or their alloys by means of flame, Plasma and similar spraying or by build-up welding to coat. The applied metals or alloys react with the industry steel and make alloy films with very good Adhesion and gas tightness. As a result of cracks or pores in However, the alloy films are often already after short time to corrosion of the coated substrates.

Especially to prevent caking and slagging, it is known the metallic coatings alternatively or additionally sealed by glassy and / or ceramic topcoats.

So was in the EP 1 386 983 proposed a boron nitride-containing coating that provides some passive protection against corrosive attack and significantly reduces the aforementioned deposits. However, it is in the in the EP 1 386 983 proposed coatings to very soft coatings, which under extreme conditions (eg, at very high flue gas velocities) may wear very quickly under certain circumstances. In addition, such boron nitride coatings can only be used up to about 850 ° C, since boron nitride begins at this temperature to react with oxygen and evaporated as boric acid.

Coatings that allow efficient protection even at high temperatures, for example, from DE 10 2006 028 963 known. The layers or coatings described there have a vitreous matrix and are characterized, inter alia, by improved gas tightness. However, the adhesion of the proposed layers or coatings did not prove to be optimal on all substrates. The gas tightness was not optimal under some conditions.

A protective coating especially for steel pipes is from the EP 1 306 469 known. The coating comprises a matrix of aluminum and particles embedded therein, the latter in the form of aluminum particles, which are coated with a ceramic film and possibly also in the form of ceramic composite particles. The latter can have up to 85% BN.

However, known glassy or ceramic topcoats, as a rule, have a comparatively very low coefficient of thermal expansion and a relatively high brittleness and, associated therewith, a lack of elasticity in comparison with the metallic substrates coated therewith on. Therefore, when the temperature fluctuations occur, flaws and detachment of the coatings very quickly occur.

It Accordingly, there continues to be a need for protective layers which As universal as possible on substrates such as those mentioned above Facilities can be applied and good adhesion have on different substrates. The protective layers should ideally be as gas-tight as possible and one offer good protection against corrosion. In addition, supposedly The coatings ideally are relatively flexible and temperature change resistant also be mechanical loads due to temperature fluctuations to be able to compensate. In particular, they should also non-stick properties exhibit the deposition of corrosive and possibly thermal isolating solids and ashes on substrates or at least delay.

These Task is solved by the layer with the characteristics of claim 1, the method of coating a substrate with the features of claim 12, the coating compositions with the features of claims 13 and 14 and the kit with the Features of claim 18. Preferred embodiments the layer of the invention are in the claims 2 to 11 indicated. Preferred embodiments of the invention Coating compositions can be found in the dependent Claims 15 to 17. In addition, the substrate with the features of claim 19 and the use of the features of claim 20 subject of the present invention. The wording of all Claims are hereby incorporated by reference Description made.

A inventive layer is on a substrate arranged and has a directly adjacent to the substrate Bottom and a side facing away from the substrate top. A layer according to the invention comprises a polymer-based Matrix and particles embedded in this matrix. The Matrix forms a three-dimensional structure within which these particles are distributed. The term "matrix" thus designates present simply a material in the particles of at least embedded in another material.

at the particles are at least partially particles a layer grid structure. Such particles are in particular from the field of inorganic lubricants or tribological solid lubricants known. On the structure of the particles will be later discussed in more detail. The layer according to the invention especially due to the proportion of such particles excellent non-stick properties. She can do the deposition of corrosive solids and ashes on substrates.

In a particularly preferred embodiment is characterized a layer according to the invention characterized in that the Concentration of lattice-structured particles in the matrix at the top of the layer is higher than at the bottom.

With In other words, the particles having a lattice structure are at the Enriched top of the layer and at the bottom of the layer depleted. Enriched here means that the local Content of particles with layer lattice structure in the area of the upper side is less than the average content of particles with layer lattice structure in the layer while depleted means that the local content of particles with layer lattice structure in the range the underside is larger than the average content on particles with layered lattice structure in the layer. The middle one Content of particles with layer lattice structure results here from the ratio of the weight of that contained in the layer Particles with layered lattice structure and the total weight of the layer multiplied by the factor 100. At the surface of the Layer located volume elements correspondingly have a higher Share of particles with layer lattice structure on comparable Volume elements that are closer to the bottom of the layer are located.

Preferably is the matrix of a layer according to the invention produced using at least one polymer precursor, in particular of at least one organometallic component, in particular from an organosilicon component. The term "polymer precursor" means all single- and multi-component systems that make connections can be produced with polymeric structure. The at least one polymer precursor can both reactive single monomers and precrosslinked monomer components exhibit.

at the at least one organosilicon component is preferably at least one polysiloxane, in particular a Poly (dimethylsiloxane) and / or a poly (methylphenylsiloxane) and / or a poly (methoxysiloxane). These systems can be both thermal as well as solidified at room temperature.

alternative or in addition to the at least one organosilicon In particular, the matrix can also be produced using at least one silazane, z. B. a perhydrosilazane or a Silazane with organic side chains such as a vinyl silazane become. Under exclusion of oxygen or reducing atmosphere may arise from the polysilazanes optionally silicon nitride, the then it is contained in the matrix or at least partially forms.

in the In line with the above, it should be noted that that is present under the term "polymer-based matrix" In particular, a matrix is to be understood that at least partially consists of high molecular chains or networks, which are essentially are built up from the same or similar structural units. The polymers may in principle be purely organic Polymers, inorganic-organic hybrid polymers such as siloxanes or silazanes, however, are preferred.

If the matrix of a layer according to the invention below Use made of at least one organosilicon component at least in significant parts from molecular chains and / or networks in which silicon atoms over Oxygen atoms and / or nitrogen atoms (eg in the case of silazanes) linked together. The remaining free valence electrons of silicon can in particular by hydrocarbon radicals be saturated as methyl or phenyl groups. If the layer but hardened at relatively high temperatures during their production was, is the proportion of hydrocarbon radicals contained in the matrix usually relatively low. Instead, they are in the matrix contained silicon atoms then preferably glass-like with each other networked.

The particles with layer lattice structure are in particular particles from the group with MoS ₂ particles, BN particles (hexagonal BN or also α-BN), WS ₂ particles, graphite particles and mixtures thereof. The term layer lattice structure is to be understood in the present case as meaning that the particles have mutually parallel layers at the molecular level, the bond between adjacent atoms being larger in one layer than adjacent atoms in a parallel layer. Particles having such a structure have in the past found particular use as solid lubricants with tribological properties, as already indicated. They can efficiently reduce the friction that occurs, as the layers that run parallel to one another can slide on top of each other. In addition, they usually have excellent non-wetting properties against materials such as water, liquid metals or even ashes and slags.

Especially The particles with layer lattice structure preferably have a middle one Particle size between 0.1 μm and 100 μm on. Particularly preferred are for the particles with layer lattice structure average particle sizes between 0.5 μm and 10 μm.

A layer according to the invention comprises in preferred embodiments platelet-shaped particles which are embedded in the matrix. The term platelet-shaped means that the particles have a very small thickness in relation to their length and / or width. Surprisingly, it was found that the gas-tightness of the layer according to the invention could be markedly improved by the presence of the platelet-shaped particles. Presumably, this is due to the fact that the diffusion path for gases such as O ₂ , HCl and Cl ₂ is considerably prolonged by the presence of the platelet-shaped particles in the layer. In order to enhance this effect, it may be preferred that the platelet-shaped particles occupy a preferred direction in the matrix.

In another particularly preferred embodiment a layer according to the invention is characterized that the concentration of the platelet-shaped particles at the bottom of the layer is higher than at the top. In other words, the platelet-shaped particles are enriched at the bottom of the layer and at the top depleted of the layer.

at the platelet-shaped particles are in particular to silicate particles such as mica particles and / or Micaceous iron oxide particles.

Especially Preferably, the platelet-shaped particles a mean particle size between 1 μm and 100 microns, more preferably between 20 microns and 80 μm, up.

In a further preferred embodiment, a layer according to the invention has at least one anticorrosive agent which is embedded in the matrix. This may be, for example, an organic corrosion inhibitor, as is common for metallic surfaces in the industry. Particularly preferably, the corrosion inhibitor is metallic particles, in particular aluminum umpartikel. In preferred embodiments, one or more organic corrosion inhibitors and metallic particles may also be present in combination.

The organic corrosion inhibitors can in particular serve corrosion of the substrate to be coated during the production of the layer according to the invention, so for example when drying a corresponding coating composition (as described below).

In a further development, it may be preferred that the metallic particles are platelet-shaped. In this embodiment, on the one hand, they can function as anticorrosive agents, but if necessary extend the diffusion path for gases such as O ₂ , HCl and Cl ₂ , thus acting analogously to the platelet-shaped particles mentioned above.

in the With regard to the metallic particles, in particular those of aluminum, it should be mentioned that these in the inventive Oxidize layer, in the matrix so if necessary, at least partially in their oxidic form.

Especially The metallic particles preferably have an average particle size between 1 .mu.m and 50 .mu.m, more preferably between 3 μm and 35 μm, on.

In a particularly preferred embodiment is characterized a layer according to the invention characterized in that the concentration of the corrosion inhibitor at the bottom the layer is higher than at the top. With others Words, the anticorrosion agent is at the bottom of the layer Enriched and depleted at the top of the layer.

A layer according to the invention comprises in preferred embodiments hard material particles. The term hard material particle means in the present case those particles which have at least a Mohs hardness of 5, in particular of 6 or higher. In particular, they are contained in the layer according to the invention in order to increase the abrasion stability of the layer and thus its service life. In particular, the hard material Cr ₂ O ₃ can also serve as corrosion protection.

Especially are the hard material particles selected from the group with oxide particles of alumina, titania or zirconia, silicate particles such as Ca silicate particles, Zr silicate particles and Al-silicate particles, silicon carbide particles, aluminum mullite particles, Zirkonmullitpartikeln, chromium oxides, spinel compounds and mixtures from that.

In another particularly preferred embodiment a layer according to the invention is characterized that the concentration of hard particles at the top of the Layer is higher than at the bottom. In other words, the hard particles are enriched at the top of the layer and depleted at the bottom of the layer.

Especially Preferably, the hard particles have an average particle size between 0.01 μm and 100 μm.

The Particularly preferred according to the invention above Embodiments of the invention Layer can each be alone or in Combination with one or more of the other particularly preferred Embodiments be realized. Especially preferred has a layer according to the invention in addition to particles with lattice structure both platelet-shaped Particles and at least one anticorrosion agent and hard particles on, z. B. metallic particles such as aluminum at the same time Exercise function of the anticorrosion agent as well as platelet-shaped can be trained (see above). In further education it is preferred that the particles with layer lattice structure and the hard material particles Enriched at the top of the layer and at the bottom depleted of the layer while the platelet-shaped Particles and the anti-corrosion agent at the bottom of the layer enriched and depleted at the top of the layer.

• – Partikeln mit Schichtgitterstruktur,
• – plättchenförmigen Partikeln,
• – Korrosionsschutzmittel und/oder
• – Hartstoffpartikeln

ein im Wesentlichen kontinuierliches Konzentrationsgefälle von der einen Seite der Schicht zur anderen aufweisen, vorzugsweise ist dies aber nicht der Fall. Es ist vielmehr bevorzugt, dass eine erfindungsgemäße Schicht einen mindestens zweilagigen Aufbau aufweist mit einer ersten Lage, die unmittelbar auf dem Substrat angeordnet ist, und einer zweiten Lage, die über der ersten Lage angeordnet ist. Innerhalb der zweiten Lage können beispielsweise die Partikel mit Schichtgitterstruktur im wesentlichen homogen verteilt sein, während die erste Lage im wesentlichen frei von Partikeln mit Schichtgitterstruktur ist. Damit ergibt sich im Querschnitt ein scharfes Konzentrationsgefälle an der Grenze zwischen der ersten und der zweiten Lage.Within the matrix, the content of

• - particles with layered lattice structure,
• - platelet-shaped particles,
• - Corrosion inhibitor and / or
• - Hard material particles

However, this is not the case, as is the case with a substantially continuous concentration gradient from one side of the layer to the other. Rather, it is preferred that a layer according to the invention has an at least two-layer structure with a first layer, which is arranged directly on the substrate, and a second layer, which is arranged above the first layer. For example, within the second layer, the layered lattice structure particles may be substantially homogeneously distributed, while the first layer is substantially free of layered lattice structure particles. This results in a sharp concentration gradient at the boundary between the first and the second layer in cross section.

As implicitly from the above, the bottom of the first layer is identical to the immediate one on the substrate adjacent underside of the invention Layer, the top of the second layer is identical to the one Substrate facing away upper side of the layer according to the invention. Preferably, the second layer is directly on the first layer arranged. Possibly. can be a bonding agent between the two layers be arranged.

• – Chemische Zusammensetzung der Matrix,
• – Gesamtfüllstoffgehalt in der Matrix,
• – Konzentration der Partikel mit Schichtgitterstruktur,
• – Konzentration der plättchenförmigen Partikel,
• – Konzentration der Hartstoffpartikel und
• – Konzentration des Korrosionsschutzmittels.

In preferred embodiments, the first and second layers differ in at least one of the following points:

• - chemical composition of the matrix,
• Total filler content in the matrix,
• Concentration of the particles with layer lattice structure,
• Concentration of the platelet-shaped particles,
• Concentration of the hard material particles and
• - Concentration of the anti-corrosion agent.

So For example, the matrix of the first and the second Able to have an identical chemical composition while the total filler content (ratio of weight all particles contained in the layer / layer and the total weight the layer / layer multiplied by the factor 100) in the first Location is higher or lower than in the second location.

The Concentration of the layered lattice structure particles is preferred in the second position higher than in the first, the same applies also for the hard material particles. With regard to the platelike Particles and the anticorrosive apply the reverse.

Also in terms of their porosity, the distinguish between two layers.

The successive application of two or more coating layers to a substrate is the preferred way to make a novel invention Layer. This is how you can easily do the above described concentration gradient of the particles with lattice structure as well as possibly adjust the other mentioned particles.

According to the inventive method for coating a Substrates, especially for producing a novel Layer is in a first step on the coated Substrate a first coating layer (corresponds to the above-mentioned first layer) formed by containing a first composition at least one organosilicon polymer precursor the substrate is applied. Subsequently, by Applying a second composition containing at least one organosilicon polymer precursor a second coating layer (corresponds to the above-mentioned second layer) on the first educated. In this case, the first composition has hard material particles and / or Particles with a lattice structure on and / or the second Composition has platelet-shaped particles and / or a corrosion inhibitor.

The first and second compositions are defined below. With regard to the preferred properties of the hard material particles, the particle with lattice structure, the platelike Particles and the anticorrosive agent is based on the above References.

The application of the compositions to the substrate can be carried out by conventional methods such as spraying, dipping, flooding, etc. The application is preferably by spraying, in particular by airless and low-pressure spraying. Preferably, the substrate surface is cleaned prior to application of the first composition, for example by blasting with melt chamber slag, corundum, glass breakage and / or glass beads. After application of the compositions, they are allowed to cure. However, it is preferred that the first coating layer is not yet cured when the second composition is applied (wet to wet application). If the second composition on a damp Beschich layer is applied and the first and the second composition have the same polymer precursor, it may be in the resulting layer according to the invention, a boundary between the first and the second layer is not recognizable, at least if both compositions have the same organosilicon polymer precursor.

With The process of the invention can be particularly Layers in a thickness between 20 microns and 200 microns produce. The thickness of the first layer is in the finished product preferably between 1 μm and 50 μm, the thickness the second layer preferably between 15 microns and 150 microns.

A in a method according to the invention in particular Coating composition usable for the preparation of the first layer includes the o. g. platelet-shaped particles and / or the o. g. Corrosion inhibitor and an organosilicon polymer precursor.

The platelet-shaped particles are preferably in a proportion between 1 wt .-% and 25 wt .-% (based on the total mass the coating composition) in the composition containing Corrosion inhibitor, if appropriate in a proportion between 1 wt .-% and 25% by weight (also based on the total weight of the coating composition).

A in a method according to the invention in particular Coating composition useful for making the second layer includes the o. g. Particles with a layered lattice structure and an organosilicon one Polymer precursor.

The Particles having a lattice structure are preferred in the composition in a proportion between 1 wt .-% and 25 wt .-% (based on the Total mass of the coating composition) in the composition contain.

Either the coating composition suitable for the preparation of the first layer as well as the coating composition suitable for the preparation of the second layer is encompassed by the present invention.

In preferred embodiments, the inventive Coating Compositions o. G. Have hard particles. In this case, the hard material particles in the two compositions be contained in different proportions. The for the production The first layer suitable coating composition comprises Hard material particles preferably in a proportion between 5 wt .-% and 75% by weight (based on the total weight of the coating composition) on, the coating composition suitable for the preparation of the second layer contains the hard particles in particular in one part between 10% by weight and 75% by weight.

As already mentioned, it is the organosilicon Polymer precursor in the inventive Coating compositions to at least one polysiloxane, in particular a poly (dimethylsiloxane) and / or a poly (methylphenylsiloxane) and / or a poly (methoxysiloxane) or a mixture thereof. Possibly. can the coating compositions of the invention in addition to the organosilicon polymer precursor at least a co-binder such as. B. has an acrylate binder. As As already indicated, it may be preferred that both coating compositions the same organosilicon polymer precursor and / or have the same co-binder. It can be in this regard but also give differences.

Especially Preferably, both in the for the production of the first Location suitable coating composition as well as in the Preparation of the second layer of suitable coating composition to a water-based coating system, essentially free of organic solvents such as alcohols, esters, Glycols etc is. This allows an application without Consideration of fire and explosion protection aspects.

Farther can the coating compositions of the invention contain commercial additives and / or fillers, so z. B. dispersants, defoamers, adjusting agents, leveling agents, Cobinder or thickener for viscosity adjustment.

The coating compositions suitable for producing the first and the second layer together form a kit by means of which layers according to the invention can be produced simply. Thus, the binder systems in the two compositions are advantageously matched, for example way to ensure a particularly good adhesion of the layer according to the invention on the substrate at the same time excellent anti-adhesion properties of the layer with respect to the initially mentioned entrained by gases corrosive solids and ashes.

The present invention encompasses any substrate or article provided with a layer according to the invention, in particular coated. It does not matter if the Subject only partially or completely with the coating according to the invention is coated.

Farther The present invention also encompasses the use of a method according to the invention Composition or a kit according to the invention for producing a layer with non-stick properties, in particular a layer according to the invention with non-stick properties.

Further Features of the invention will become apparent from the following description of preferred embodiments in connection with the Dependent claims. Here are the individual Characteristics individually or in combination be realized with each other in one embodiment of the invention. The specific embodiments described are merely intended to explain and to better understand the Invention and are in no way limiting.

figure description

In 1 schematically an embodiment of a layer according to the invention is shown. The layer according to the invention 101 is on a substrate 100 applied. Within the shift 101 are particles with layer lattice structure 102 (drawn as triangles) embedded. Here are the particles 102 on the side facing away from the substrate top of the layer 101 Enriched while the concentration of particles 102 on the underside of the layer directly adjacent to the substrate 101 is close to zero.

In 2 a further embodiment of a layer according to the invention is shown schematically. On a substrate 200. is a layer according to the invention of a first layer 201 and a second location 201b applied. The first location 201 it borders directly on the substrate 200. while the second location 201b to the first location 201 borders. In the second situation 201b are particles with layer lattice structure 202 (drawn as triangles) embedded. The particles 202 have it within the second layer 201b a substantially homogeneous distribution. The first location 201 is, on the other hand, free of particles 202 , Accordingly, the concentration of the particles is also here 202 having a lattice structure at the substrate 200. remote top of the layer higher than at the directly on the substrate 200. adjacent bottom of the layer.

A further preferred embodiment of the layer according to the invention is schematically based on 3 explained. Here is on a substrate 300 a first location 301 applied, on the turn a second layer 301b is arranged. The first location 301 and the second location 301b together form a layer according to the invention. In the first situation 301 are aluminum particles 304 (drawn as rectangles) embedded. The aluminum particles 304 have a platelet-shaped shape and are arranged in a preferred direction. They can serve both as a corrosion inhibitor and as a gas barrier within the first layer. In the second location 301b are particles with layer lattice structure 302 (drawn as triangles) embedded. The particles 302 are within the location 301b essentially homogeneously distributed. The first location 301 is free of particles 302 while the second location 301b free of aluminum particles 304 is. Accordingly, within the layer according to the invention there is a concentration gradient between the upper side and the lower side of the layer, both with regard to the particles with layer lattice structure 302 and the aluminum particles 304 , The aluminum particles 304 are enriched at the bottom of the layer and depleted at the top of the layer, while the particles with layer lattice structure 302 enriched at the top of the layer and depleted at the bottom of the layer.

Examples

Coating compositions suitable for producing a first layer and a second layer were blended from the following components: Composition for first layer: component Mixture A (g) Mixture B (g) 1 TiO ₂ [40% by weight] -Waterr. suspension 12,01 20.15 2 Silres ^® MP 42 E 67.03 67.44 3 Aluminum pigment [45% by weight] - Watersr. suspension 18.25 10.19 4 AMP 0.3 0.5 5 Thickener 2: 1 (Byk 420: butylglycol) 1.67 1.60 6 Color Dye Blue 0.2 0.2

The composition contains TiO ₂ as a nanoscale Hartfüllstoff, a silicon-organic polymer precursor (Silres ^® MP42 E, a Methylphenylsiliconharz), an aluminum pigment as a corrosion inhibitor, and additives (thickeners and AMP = 2-amino-2-methyl-1-propanol) and a dye (Dye Blue) to distinguish the coating from the substrate during application. Composition for second layer: component Mixture C (g) Mixture D (g) Mixture E (g) 1 WS ₂ [50% by weight] - Wässr. suspension 27,01 40.11 40.04 2 BN [40% by weight] - Wässr. suspension 33.21 20.03 15.06 3 Al ₂ O ₃ [75] anorg. 15.1 15,01 10.02 4 SiC [50% by weight] water suspension - - 12.0 5 Silres ^® MP 42 E 30.0 30.0 30.0 6 AMP 2.0 2.0 2.0 7 Korantin ^® MAT 1.0 1.0 1.0 8th Deuteron ^® XG [2 wt%] 2.0 2.07 2.0 Total: 110.32 110.22 112.12

The composition contains WS ₂ and BN as particles having a layer lattice structure, Al ₂ O ₃ and SiC as Hartfüllstoff, a silicon-organic polymer precursor (Silres ^® MP 42 E, a Methylphenylsiliconharz), an organic corrosion inhibitors (Korantin ^® MAT) and additives (deuteron ^® XG as Thickener and AMP = 2-amino-2-methyl-1-propanol).

These Compositions are particularly suitable for the coating of Substrates made of steel (eg tubes made of 10CrMo910 or 15Mo3). The Surfaces of the substrates should be free of dust and grease, why possibly to be coated substrates z. B. by blasting Pre-treated glass beads, melt chamber slag or electrocorundum should be.

to Production of a first layer (base coat) on a tubular metallic test substrate from 15Mo3 boiler steel was this with Mixture A sprayed. The spray application took place by application with a HVLP spray gun (low pressure). The wet film thickness was between 60 and 80 μm. After this Order was the coating at room temperature (about 25 ° C) About 30 to 60 minutes vented.

After that a second layer (topcoat) was applied to the first layer, by applying mixture D to the ventilated nasal layer has been. The wet layer thickness of the topcoate was between 80 and 100 μm.

To re-flash for 30 min at room temperature the layers were solidified at temperatures above 200 ° C. (In practice, the layer can also be solidified "in situ" be, for. B. from 200 ° C tube surface temperature during thermal start-up of a boiler plant). It was a hardened inventive layer with a thickness of approx. 60 microns received.

Slag tests were performed on the coated test substrate. That means that on the coated substrate chloride and / or sulfur-containing combustion residues (slags) from various power plants were applied and were applied at 600 ° C for 24 hours. The substrate was then examined. The slags were then very easy to remove with a brush and did not cause caking on the coating surface. The layer proved to be very scratch resistant and had no cracks or flaking. The substrate, unlike an uncoated blank, showed no damage from corrosive attack of the chlorides from the slag. The tendency of the pipe to scale was also strongly suppressed.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1386983 [0006, 0006]
• - DE 102006028963 [0007]
• EP 1306469 [0008]

Claims (20)

Layer on a substrate having a directly adjacent to the substrate bottom and an upper side facing away from the substrate comprising a polymer-based matrix and particles embedded in the matrix, wherein the particles are at least partially particles with a lattice structure, characterized in that the concentration of the lattice-structured particles in the matrix is higher at the top of the layer than at the bottom. Layer according to claim 1, characterized that the matrix using at least one polymer precursor is made, in particular from at least one organosilicon Component. Layer according to claim 1 or claim 2, characterized in that the particles with layer lattice structure from the group with MoS ₂ particles, BN particles, WS ₂ particles, graphite particles and mixtures thereof are selected. Layer according to one of the preceding claims or according to the preamble of claim 1, characterized that it comprises platelet-shaped particles which embedded in the matrix, it being preferred that the Concentration of the platelet-shaped particles the bottom of the layer is higher than at the top. Layer according to claim 4, characterized that the platelet-shaped particles silicate Particles, in particular mica particles, are. Layer according to one of the preceding claims or according to the preamble of claim 1, characterized that it comprises a corrosion inhibitor embedded in the matrix wherein it is preferred that the concentration of the corrosion inhibitor at the bottom of the layer is higher than at the top. Layer according to claim 6, characterized that the corrosion inhibitor is metallic particles, especially aluminum particles. Layer according to claim 7, characterized that the metallic particles are platelet-shaped are formed. Layer according to one of the preceding claims or according to the preamble of claim 1, characterized that it comprises hard material particles, it being preferred that the concentration of hard particles at the top of the layer is higher than at the bottom. Layer according to one of the preceding claims, characterized in that they have at least a two-layer structure having a first layer directly on the substrate is arranged, and a second layer, which is above the first Location is arranged. Layer according to claim 10, characterized that the first layer and the second layer in at least one different from the following points: - Chemical Composition of the matrix, - total filler content in the matrix, Concentration of the particles with layer lattice structure, - concentration on platelet-shaped particles, - concentration on hard material particles and - Concentration of the anti-corrosion agent. Process for coating a substrate, in particular for producing a layer according to one of the preceding claims, wherein a first coating layer is formed on the substrate in a first step is characterized by a first composition containing at least one organosilicon polymer precursor applied to the substrate and then by applying a second composition containing at least one organosilicon polymer precursor a second coating layer is formed on the first, wherein the first composition is platelet-shaped particles and / or having a corrosion inhibitor and / or the second Composition Hard material particles and / or particles with a lattice structure having. Coating composition, in particular for the production a first layer in a process or in a layer one of the preceding claims comprising - platelet-shaped Particles, preferably in a proportion between 1 wt .-% and 25 % By weight (based on the total weight of the coating composition), and / or a corrosion inhibitor, preferably in one proportion between 1 wt .-% and 25 wt .-% (based on the total mass of Coating composition) and - an organosilicon polymer precursor Coating composition, in particular for the production a second layer in a process or in a layer one of the preceding claims comprising - Particles with a layer grid structure, preferably in a proportion between 1% by weight and 25% by weight (based on the total weight of the coating composition) and An organosilicon polymer precursor A coating composition according to any one of the claims 13 or 14, in particular according to claim 14, characterized that it contains hard material particles, preferably in one Proportion between 5 wt .-% and 75 wt .-% (based on the total mass the coating composition). A coating composition according to any one of the claims 13 to 15, characterized in that it is in the organosilicon Polymer precursor to at least one polysiloxane, in particular a poly (dimethylsiloxane) and / or a poly (methylphenylsiloxane) and / or a poly (methoxysiloxane). A coating composition according to any one of the claims 13 to 16, characterized in that they in addition to the organosilicon Polymer precursor at least one co-binder such. B. having an acrylate binder. Kit for producing a coating according to one of Claims 1 to 11 or for use in a method according to claim 12, comprising a coating composition according to Claim 13 and a coating composition according to claim 14th Substrate, characterized in that it is a layer according to one of claims 1 to 11. Use of a composition or a kit according to any one of the preceding claims for the preparation a layer with non-stick properties, in particular a layer according to one of claims 1 to 11.