DE102008023569A1 - Protective coating resisting corrosive attack by aggressive flue gases in power stations and incinerators, contains oxidizing agent, catalyst and additives in polymeric matrix - Google Patents

Abstract

The protective layer applied to the substrate includes a polymer based matrix, an oxidizing agent and/or an oxidation catalyst. Either or both of the latter are embedded in the matrix. These agents oxidize, or promote oxidation of, organic residues and/or light metals. The oxidant is an oxygen-containing compound. It comprises one or more of: manganese (IV) oxide, permanganates, perborates, peroxides, percarbonates, cerium dioxide, cerates, lead (IV) oxide, peroxycarbonates, peroxophosphates and copper (II) oxide. Particles of at least one oxidant in the matrix have sizes in the range 0.1 mu m - 100 mu m. The oxidation catalyst comprises one or more of the transition metal oxides: vanadium-, molybdenum-, tungsten-, rhenium-, cobalt-, nickel-, iron- and manganese oxide. Its mean particle size is in the range 1nm - 100 mu m. The concentration of oxidant is greatest at the surface of the layer. Metallic particles, especially of aluminum, are embedded in the matrix, in homogenous distribution. The catalyst of the catalyst is greater on the underside than at the surface. The particles have a layered-lattice structure, being selected from MoS 2, BN, WS 2, graphite, and their mixtures. Preferably their distribution is uniform. The embedded particles are platelets and are uniformly-distributed. At least one polymer precursor is used to make the layer, especially one or more silicon-organic components are used. Two layers, one above the other are used on the substrate. They differ in matrix chemical composition or its filler content. They differ in terms of concentrations of the following: oxidant, catalyst, metallic particles, particles with lattice layer structure, platelets and hard material particles. Further details of a corresponding method are provided, in accordance with the foregoing principles. An independent claim IS INCLUDED FOR The method of protecting substrates from corrosion.

Description

The The present invention relates to a layer which is a protective coating for facilities in power plants and industry, coating compositions, which are suitable for producing such a layer and substrates, which have 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 to biomass plants 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 can Problems arise because of the dragged by the gases corrosive solids and ashes on said facilities deposit firmly attached. Such deposits can, for example the heat transfer from a combustion chamber to a heat exchanger, continue to reduce the life of the steel surfaces and have to removed at regular intervals be, either during operation, for example by means of water lances or so-called sootblower, or during standstill, then especially by mechanical removal by sandblasting, brushing, by means of a compressed air hammer or even controlled demolition.

To the Protection of said industrial steels Before corrosion, it is known that the steel surfaces with metals such as aluminum, Silicon, nickel and chromium or their alloys by means of flame, Plasma and similar Spraying or even by build-up welding to coat. The applied Metals or alloys react with the industrial steel, forming Alloy films with very good adhesion and gas tightness. As a result However, cracks or pores in the alloy films often occur after a short time to corrosion of the coated substrates.

In particular, to prevent caking and slagging, it is known to seal the metallic coatings alternatively or additionally by glassy topcoats. The starting point for this are coating compositions which harden on heating, for example when starting up an incinerator. Optionally contained in the composition of organic constituents volatilize or are oxidized. Thus, for example, from a layer having a matrix of a poly (organo) siloxane at high temperatures, a vitreous coating can be formed, which is substantially free of organic residues. However, the atmosphere is z. As in flue gas streams usually extremely low in oxygen, which can lead to the fact that the oxidation of the organic components is very slow or incomplete. As a result, amorphous carbon can be formed instead of CO ₂ and stored in the layer. The result may be a partially or incompletely cured coating which quickly cracks and leaks and does not provide adequate protection against corrosive attack.

Of the The present invention was based on the object, a protective layer to provide as much as possible universal on substrates such as the aforementioned devices Adheres well and especially under low oxygen conditions Harden can. The protective layer should ideally ideally as possible be gas-tight and provide good protection against corrosion. Furthermore the coating should be relatively flexible and resistant to thermal shock, also mechanical loads as a result of temperature fluctuations to be able to compensate. In particular, it should also have non-stick properties to the Separation of corrosive and possibly thermally insulating solids and to prevent ashes on substrates, or at least delay them.

This object is achieved by the layer having the features of claim 1, the method having the features of claim 16 and the coating composition having the features of claim 17. Preferred embodiments of the layer according to the invention are specified in claims 2 to 15. Preferred embodiments of the coating composition according to the invention fin In addition, the substrate with the features of claim 25 as well as the use with the features of claim 26 is the subject of the present invention. The wording of all claims is hereby incorporated by reference into the content of this specification.

A inventive layer is arranged on a substrate and serves in particular for protection of the substrate from corrosion. The bottom of the layer is immediately on the substrate, its upper side facing away from the substrate. The inventive layer can be designed both as a single layer and as a multi-layer layer be what later will be described in more detail.

A inventive layer comprises a polymer-based matrix and at least one oxidizing agent and / or at least one oxidation catalyst incorporated in this matrix are embedded. The matrix forms a three-dimensional structure within which distributes the oxidizing agent and / or the oxidation catalyst are. The term "matrix" denotes Thus present simply a material into which at least one other Material is embedded.

Preferably are at least one oxidizing agent and / or at least an oxidation catalyst chosen such that they are able organic radicals, especially radicals such as phenyl or methyl groups and in the production of the layer added organic additives to oxidize and / or at least promote their oxidation. Especially they should be used for the oxidation of hydrocarbon radicals in poly (organo) siloxanes can contribute. The at least one oxidizing agent preferably has a sufficient Oxidation potential to light metals such as aluminum in particular to oxidize. It usually becomes dependent chosen to be coated substrate, wherein in preferred embodiments particularly Care is taken that the substrate itself by the chosen oxidizing agent can not be attacked. This is particularly preferred at least an oxidizer free of chlorine and sulfur compounds.

at the at least one oxidizing agent is preferably at least one oxygen-containing compound, in particular to at least one compound from the group with manganese (IV) oxide, permanganates, Perborates, peroxides, percarbonates, cerium dioxide, cerates, lead (IV) oxide, Peroxocarbonates, peroxophosphates and copper (II) oxide. Particularly preferred is the at least one oxidizing agent in the form of particles, in particular with a mean particle size in the range between 0.1 μm and 100 μm, in the matrix.

at the at least one oxidation catalyst is preferably at least one transition metal oxide, in particular by at least one oxide from the group with vanadium, Molybdenum-, Tungsten, rhenium, cobalt, nickel, iron and manganese oxides. In preferred embodiments can as oxidation catalyst in addition or in place of the at least one transition metal oxide or more precious metals such. As platinum may be included. As iron oxide is especially hematite prefers. Furthermore you can as oxidation catalyst in particular also lanthanum compounds be included.

Especially Preferably, the at least one oxidation catalyst is in the form of particles, in particular with an average particle size in the range between 1 nm and 100 μm, in particular between 5 nm and 1 μm, in the matrix.

Surprisingly has been found that by adding the mentioned oxidizing agents and oxidation catalysts greatly increase the problem of incomplete curing could be reduced. Lack of oxygen from the atmosphere can at least partially of oxidant contained in the layer be provided and contained in the layer oxidation catalysts take care of a more efficient oxygen conversion, so that the inventive layer can cure quickly even under low-oxygen conditions. For the exact composition of the layer and for its production later even more.

In As a rule, it is preferred that the at least one oxidizing agent and / or the at least one oxidation catalyst substantially are homogeneously distributed in the matrix.

In particular, in cases where the substrate is particularly sensitive to oxidation, it may also be preferred that the concentration of the at least one oxidizing agent in the matrix is higher at the top of the layer than at the bottom. In other words, the oxidizer is enriched at the top of the layer and depleted at the bottom of the layer. Enriched means in the present case that the local content of the oxidant in the upper side is greater than the average of the oxidant in the layer, while depleted means that the local content of the oxidizer in the lower side is larger than the average content of the oxidizer in the layer. The average content of oxidizing agent results from the ratio of the weight of the oxidizing agent contained in the layer and the total weight of the layer multiplied by the factor 100. Volume elements present on the surface of the layer correspondingly have a higher proportion of oxidizing agent than comparable volume elements are closer to the bottom of the layer.

Especially in the cases in which the concentration of the at least one oxidizing agent in the matrix at the top of the layer is higher than at the bottom, can compensate for the concentration of the at least one oxidation catalyst be higher in the matrix at the bottom of the layer than at the top.

In particularly preferred embodiments, a layer according to the invention comprises metallic particles, in particular aluminum particles, which are embedded in the matrix and preferably distributed homogeneously in it. In a further development, it may be preferred that the metallic particles are platelet-shaped. In this embodiment, on the one hand, they can act as anticorrosive agents, but may also extend the diffusion path for gases such as O ₂ , HCl and Cl ₂ .

Especially The metallic particles preferably have an average particle size between them 1 μm and 50 μm, especially preferably between 3 microns and 35 μm, on.

In a particularly preferred embodiment is a layer according to the invention characterized in that the concentration of the metallic particles the bottom of the layer higher is as at the top. Or with the words above, the metallic ones Particles are enriched and attached to the bottom of the layer the top of the layer depleted.

The metallic particles, especially those made of aluminum, can be used in oxidize the layer according to the invention, lie in the matrix so possibly at least partially in their oxidic Form before. It turned out to be with regard to the tightness of the coating can even be beneficial, the Promote oxidation of metallic particles. Accordingly, it can it is preferable that the concentration of the at least one oxidizing agent and / or the at least one oxidation catalyst in the matrix adapted to the concentration of the metallic particles. are the metallic particles enriched at the bottom, so points preferably also the at least one oxidizing agent and / or the at least one oxidation catalyst at the bottom of the Layer a higher one Concentrate on being at the top.

Farther may be a layer of the invention Particles having a layered lattice structure, which in preferred embodiments are homogeneously distributed in the layer. Such particles are in particular from the field of inorganic lubricants or the tribological Solid lubricants known.

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.

Prefers the particles with layer lattice structure between an average particle size 0.1 μm and 100 μm. Particularly preferred are for the particles with layer lattice structure mean particle sizes between 0.5 μm and 10 μm.

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

A layer according to the invention may in non-metallic platelets in preferred embodiments comprise shaped particles embedded in the matrix. In preferred embodiments, the platelet-shaped particles may be homogeneously distributed in the matrix. The term platelet-shaped in the context of the present invention means that the particles have a very small thickness in relation to their length and / or width. As already mentioned, the presence of platelet-shaped particles can significantly improve the gas-tightness of the layer according to the invention. In order to enhance this effect, it may be preferred that the platelet-shaped particles occupy a preferred direction in the matrix.

In preferred embodiments may be a layer of the invention characterized in that the concentration of the platelet-shaped particles higher at the bottom of the layer is as at the top.

at the non-metallic platelet-shaped particles these are, in particular, siliceous particles such as mica particles and / or iron mica particles.

Especially Preferably, the non-metallic platelet-shaped particles have an average Particle size between 1 μm and 100 μm, more preferably between 20 microns and 80 μm, on.

A inventive layer comprises in preferred embodiments Hard particles. The term hard material particle means here Such particles having at least a Mohs hardness of 5, in particular of 6 or higher, exhibit. They are in particular contained in the layer according to the invention, about the abrasion stability the layer and thus increase its life. In preferred embodiments, the Hard material particles are homogeneously distributed in the matrix.

Especially are the hard material particles selected from the group with oxidic Particles of alumina, titania or zirconia, siliceous Particles such as Ca silicate particles, Zr silicate particles and Al silicate particles, Silicon carbide particles, aluminum mullite particles, zirconium mullite particles, Chromium oxides, spinel compounds and mixtures thereof.

In preferred embodiments may be a layer of the invention characterized in that the concentration of the hard material particles higher at the top of the layer is as at the bottom. Or with the words above, the hard material particles are enriched at the top of the layer and at the bottom depleted of the layer.

Especially The hard material particles preferably have an average particle size between them 0.01 μm and 100 μm on.

Preferably is the matrix of a layer according to the invention using at least one polymer precursor produced, in particular from at least one organometallic Component, in particular of 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 thermally and solidified at room temperature.

alternative or additionally to the at least one organosilicon component, the Matrix, in particular also using at least one silazane, z. As a perhydrosilazane or a silazane with organic Side chains such as a vinyl silazane, are produced. 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 under the term "polymer-based Matrix "present 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 act, inorganic-organic hybrid polymers such as siloxanes or Silazanes, however, are preferred.

If the matrix of a layer according to the invention using at least one organosilicon component it has been produced at least substantially Parts of molecular chains and / or nets in which silicon atoms via oxygen atoms and / or Nitrogen atoms (eg in the case of silazanes) are linked together. The remaining free valence electrons of silicon can thereby in particular by hydrocarbon radicals such as methyl or phenyl groups saturated be. However, when the layer is manufactured at a relative level cured at high temperatures was, is the proportion of hydrocarbon radicals contained in the matrix usually relatively low, not least due to the presence of the at least one oxidizing agent and / or the at least one Oxidation catalyst is due. Instead, the silicon atoms contained in the matrix are then preferably glass-like crosslinked with each other.

at The polymer-based matrix may therefore be a particular Inorganic-organic hybrid matrix with Si-O chains and networks and organic radicals such as the methyl or phenyl groups or around a glassy matrix, depending of which temperatures the matrix was cured at.

• – dem mindestens einen Oxidationsmittel,
• – dem mindestens einen Oxidationskatalysator,
• – den Partikeln mit Schichtgitterstruktur,
• – den plättchenförmigen Partikeln,
• – den metallischen Partikel und/oder
• – den Hartstoffpartikeln

ein im Wesentlichen kontinuierliches Konzentrationsgefälle von der einen Seite der Schicht zur anderen aufweisen, in der Regel 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 ersten Lage können beispielsweise das mindestens eine Oxidationsmittel und/oder der mindestens eine Oxidationskatalysator im wesentlichen homogen verteilt sein, während die zweite Lage im wesentlichen frei von dem mindestens einen Oxidationsmittel und/oder dem mindestens einen Oxidationskatalysator 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

• The at least one oxidizing agent,
• The at least one oxidation catalyst,
• - the particles with layered lattice structure,
• The platelet-shaped particles,
• The metallic particles and / or
• - the hard material particles

However, as a rule, this will not be the case for 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. Within the first layer, for example, the at least one oxidant and / or the at least one oxidation catalyst may be substantially homogeneously distributed while the second layer is substantially free of the at least one oxidant and / or the at least one oxidation catalyst. This results in a sharp concentration gradient at the boundary between the first and the second layer in cross section.

As from the above implicitly, is the bottom of the first layer identical to the directly adjacent to the substrate bottom the layer according to the invention, the top of the second layer is identical to that of the substrate remote top side of the layer according to the invention (if not yet a third layer is disposed on the second). Preferably the second layer is disposed directly on the first layer. Possibly. can be arranged between the two layers of a bonding agent.

• – Chemische Zusammensetzung der Matrix,
• – Gesamtfüllstoffgehalt in der Matrix,
• – Konzentration des Oxidationsmittels,
• – Konzentration des Oxidationskatalysators,
• – Konzentration an metallischen Partikeln,
• – Konzentration der Partikel mit Schichtgitterstruktur,
• – Konzentration an plättchenförmigen Partikeln und
• – Konzentration an Hartstoffpartikeln.

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 oxidizing agent,
• Concentration of the oxidation catalyst,
• - concentration of metallic particles,
• Concentration of the particles with layer lattice structure,
• Concentration of platelet-shaped particles and
• - Concentration of hard material particles.

So can For example, the matrix of the first and the second layer identical chemical composition while the total filler content (Relationship the weight of all the particles contained in the layer / layer and the total weight of the layer / layer multiplied by the factor 100) in the first position higher or lower than in the second layer.

The Concentration of the layered lattice structure particles is preferred higher in the second position as in the first, the same applies to the hard material particles. in the With regard to the platelet-shaped particles and the metallic particles are the reverse.

Also in terms of their porosity can the two layers differ.

One inventive method to protect a substrate against corrosion, in particular by producing a Layer according to one of the preceding claims, characterized in particular characterized in that containing on the substrate a composition at least one polymer precursor and at least one oxidizing agent and / or at least one oxidation catalyst is applied. Regarding the properties of these components is based on the above Referenced.

As mentioned above, can the layer of the invention designed both as a single layer and as a multilayer layer be, in particular in the latter embodiment, a concentration gradient z. In the With regard to the oxidizing agent and / or the oxidation catalyst can exist.

The successive application of two or more coating layers to a substrate is the preferred way to produce a layer according to the invention with continuous or discontinuous concentration gradient of one side of the layer to the other. So can be z. B. in a fairly simple manner set the above-described concentration gradient of the oxidizing agent, by placing on a substrate before applying a composition with the oxidizing agent, a base layer (corresponds to the above mentioned first layer) is formed from a composition which is substantially free of which is at least one oxidizing agent. Only then follows the formation of a second layer by application of the oxidant-containing Composition on the still wet or at least moist first Location and then the curing. As a result, the oxidizer is then at the top of the layer enriched.

The Applying the composition comprising the at least one oxidizing agent and / or the at least one oxidation catalyst on a substrate can via usual procedures like spraying, Diving, floods etc. take place. The application is preferably by spraying, in particular by airless and low pressure spraying. Preferably the substrate surface cleaned before applying the composition, for example by blasting with melt chamber slag, corundum, glass breakage and / or Glass beads. After application of the composition is allowed they harden. When applying several coating compositions for production a concentration gradient it is preferred that the first coating layer is not yet cured, when the second composition is applied (wet on wet order). If the second composition on a wet coating is applied and the first and the second composition the same polymer precursor optionally, in the resulting layer according to the invention a border between the first and the second position is not recognizable.

With the method according to the invention In particular, layers can be produced in a thickness between 20 .mu.m and 200 .mu.m.

A coating composition according to the invention, itself for use in a method according to the invention or for the manufacture ment a layer according to the invention always comprises at least one polymer precursor, in particular at least one organosilicon polymer precursor, and at least one oxidizing agent and / or at least one oxidation catalyst. Also regarding The properties of these components will be based on the above Referenced.

The Oxidizing agent is preferably in the composition in one Proportion between 0.1 wt .-% and 25 wt .-%, in particular between 0.5% by weight and 10% by weight (based on the total weight of the coating composition) contain, the oxidation catalyst preferably in a proportion between 0.0001% by weight and 5% by weight, in particular between 0.01 Wt .-% and 1 wt .-% (also based on the total mass of the coating composition).

As already mentioned, is the organosilicon polymer precursor in the coating compositions according to the invention preferably 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 they Coating compositions of the invention in addition to the organosilicon polymer precursor at least one co-binder such. B. have an acrylate binder.

In preferred embodiments has a coating composition of the invention o. g. non-metallic platelet-shaped particles and / or the o. g. metallic particles on. The stoichiometric relationship of metal particles: oxidizing agent and / or oxidation catalyst is preferably> 1. The non-metallic platelet-shaped particles are preferably present in a proportion between 1% by weight and 25% by weight. (based on the total mass of the coating composition) in of the composition.

Farther It may be preferred that the coating composition of the invention the o. g. Comprises particles with a lattice structure. The particles With 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 preferred embodiments can the coating composition of the invention the o. g. Have hard particles, in particular in a proportion between 10 wt .-% and 75 wt .-% (based on the total mass of Coating composition).

Farther can Coating compositions of the invention commercial Additives and / or fillers included, such. B. dispersants, defoamers, adjusting agents, leveling agents, organic corrosion inhibitors, cobinders or thickeners for viscosity adjustment.

Especially The coating composition according to the invention is preferably in the form of a water-based coating system that is essentially free of organic solvents such as alcohols, esters, glycols etc. This allows a Application without consideration of fire and explosion protection aspects.

The present invention encompasses any substrate or article with a layer according to the invention provided, in particular coated, is (for example, objects and Facilities with surfaces from the steels mentioned above). It is irrelevant whether the object is only partially or not Completely with the layer according to the invention is coated.

Farther The present invention also encompasses the use of a composition according to the invention to protect a substrate against corrosion, in particular for producing a layer according to the invention, as described above.

Further Features of the invention will become apparent from the following description of preferred embodiments in conjunction with the subclaims. Here you can the individual features for each one or more in combination with one another in one embodiment be realized the invention. The particular embodiments described are for explanation only and for better understanding of the invention and are in no way limiting.

Examples

For the production of a layer according to the invention, for example, the following compositions are suitable: Composition A component Mixture A (g) Mix A (FS%) 1 TiO2 [45] suspension 16.05 9.11 2 Silres MP 42 E 130 68,90 3 Aluminum pigment [40] 53.2 16.16 4 DMEA 0.35 - 5 Thickener 2: 1 (Byk 420: butylglycol) 1.8 0.82 6 Copper (II) oxide 4.0 5.04 7 Color Dye Blue 0.6 - Total: 206.0 100.3

The composition contains TiO ₂ as a nanoscale Hartfüllstoff (average grain size 45 microns), a silicon-organic polymer precursor (Sil res ^® MP42 E, a Methylphenylsiliconharz), an aluminum pigment (average particle size 40 microns) and additives (thickeners) and a dye (Dye Blue), to distinguish the coating from the substrate during application. As the oxidizing agent copper (II) oxide is used (5.04% calculated on the solids content of the total formulation). Composition B component Mixture B (g) Mix B (FS%) 1 TiO2 [45] suspension 16.05 8,767 2 Silres MP 42 E 128 65.26 3 Aluminum pigment [40] 53.0 15.44 4 DMEA 0.35 - 5 Thickener 2: 1 (Byk 420: butylglycol) 1.6 0.58 6 Manganese (IV) oxide 8.2 9.95 7 Color Dye Blue 0.6 - Total: 207.8 99.997%

The composition contains TiO ₂ as a nanoscale Hartfüllstoff (average grain size 45 microns), a silicon-organic polymer precursor (Silres ^® MP42 E, a Methylphenylsiliconharz), an aluminum pigment (average particle size 40 microns) and additives (thickeners) and a dye (Dye Blue) to to differentiate the coating from the substrate during application. As oxidizing agent manganese dioxide is used (9.95% calculated on the solids content of the total formulation). Composition C component Mixture C (g) Mix C (FS%) 1 TiO2 [45] suspension 16.05 8.85 2 Silres MP 42 E 130 66.88 3 Aluminum pigment [40] 53.2 15.64 4 DMEA 0.35 - 5 Thickener 2: 1 (Byk 420: butylglycol) 1.8 0.8 6 Manganese (IV) oxide 6.4 7.84 7 Color Dye Blue 0.6 - Total: 208.4 100.01

The composition contains TiO ₂ as a nanoscale Hartfüllstoff (average grain size 45 microns), a silicon-organic polymer precursor (Silres ^® MP42 E, a Methylphenylsiliconharz), an aluminum pigment (average particle size 40 microns) and additives (thickeners) and a dye (Dye Blue) to to differentiate the coating from the substrate during application. As oxidizing agent manganese dioxide is used (9.95% calculated on the solids content of the total formulation).

The Compositions A to C can directly on a substrate (eg 10CrMo910 or 15Mo3 tubes) be applied. The surfaces The substrates should be free of dust and grease, therefore possibly too coating substrates z. B. by blasting with glass beads, melt chamber slag or electrocorundum should be pretreated.

Especially The compositions A to C are suitable for the preparation of a multilayered layer. You will then in a first step as first layer applied to a substrate, whereupon in a second Step a second layer on the first by placing another Composition is formed. Thereafter, the layers are cured.

For the preparation of the second layer, for example, the following compositions D to F are suitable: suspension component Mixture D (g) Mixture E (g) Mixture F (g) 1 WS ₂ [50% by weight] -Waterr. suspension 27,01 40.11 40.04 2 BN [40 wt .-%] - Wässr. 33.21 20.03 15.06 3 Al ₂ O ₃ [75] anorg. 15.1 15,01 10.02 4 SiC [50% by weight] Watersr. 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).

In particular, with the addition of particles having a layered lattice structure, such as WS ₂ and BN, the compositions A to C can also be used, without restriction, for the production of a single-layer layer according to the invention.

Claims (26)

Layer on a substrate, in particular for Protection of the substrate from corrosion, with a directly on the Substrate adjacent bottom and one facing away from the substrate Topside comprising a polymer-based matrix and at least an oxidizing agent and / or at least one oxidation catalyst, that and / or embedded in the matrix. Layer according to claim 1, characterized that the at least one oxidizing agent and / or the at least an oxidation catalyst capable of organic radicals and / or To oxidize light metals and / or to promote their oxidation. A layer according to claim 1 or claim 2, characterized characterized in that the at least one oxidizing agent is an oxygen-containing Compound, in particular at least one compound from the group with manganese (IV) oxide, permanganates, perborates, peroxides, percarbonates, Ceria, cerates, lead (IV) oxide, peroxocarbonates, peroxophosphates and cupric oxide. Layer according to one of the preceding claims, characterized characterized in that the at least one oxidizing agent in the form of particles, in particular with an average particle size in the range between 0.1 μm and 100 μm, present in the matrix. Layer according to one of the preceding claims, characterized characterized in that the at least one oxidation catalyst at least a transition metal oxide from the group comprising vanadium, molybdenum, tungsten, rhenium, cobalt, Nickel, iron and manganese oxide. Layer according to one of the preceding claims, characterized characterized in that the at least one oxidation catalyst in Form of particles, in particular with a mean particle size in the range between 1 nm and 100 μm, present in the matrix. Layer according to one of the preceding claims, characterized in that the concentration of the at least one oxidizing agent in the matrix at the top of the layer is higher than at the bottom. Layer according to one of the preceding claims, characterized in that they contain metallic particles, in particular aluminum particles which are embedded in the matrix, it being preferred is that the metallic particles in the matrix essentially are distributed homogeneously. Layer according to one of the preceding claims, characterized in that the concentration of the at least one oxidation catalyst in the matrix at the bottom of the layer is higher than at the top. Layer according to any one of the preceding claims, characterized in that it comprises, WS thereof having ₂ particles, graphite particles and mixtures of particles having a layer lattice structure, in particular from the group of MoS ₂ particles, BN particles, it is preferred that the Particles having a layered lattice structure are distributed substantially homogeneously in the matrix. Layer according to one of the preceding claims, characterized characterized in that they are platelet-shaped particles which are embedded in the matrix, it being preferred is that the platelet-shaped particles are distributed substantially homogeneously in the matrix. Layer according to one of the preceding claims, characterized characterized in that it comprises hard material particles, it being preferred is that the hard particles in the matrix are substantially homogeneous are distributed. Layer according to one of the preceding claims, characterized characterized in that the matrix using at least one polymer precursor is made, in particular using at least one organosilicon component. Layer according to one of the preceding claims, characterized characterized in that it has an at least two-layered construction with a first layer disposed directly on the substrate is, and a second layer, which is located above the first layer is. Layer according to claim 14, 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 the oxidizing agent, - concentration the oxidation catalyst, - concentration of metallic particles - concentration the particle with lattice structure, - Concentration of platelet-shaped particles and - concentration on hard material particles. Method of protecting a substrate from corrosion, in particular by producing a layer according to one of the preceding Claims, wherein on the substrate a composition tion containing at least a polymer precursor and at least one oxidizing agent and / or at least one oxidation catalyst is applied. Coating composition, in particular for use in a process or for producing a layer after one of the preceding claims, full - at least an oxidizing agent, preferably in an amount between 0.1 Wt .-% and 25 wt .-%, and / or at least one oxidation catalyst, preferably in a proportion of between 0.0001% by weight and 5% by weight, and - at least a polymer precursor, in particular at least one organosilicon polymer precursor. Coating composition according to claim 17, characterized characterized in that the organosilicon polymer precursor is um at least one polysiloxane, in particular a poly (dimethylsiloxane) and / or a poly (methylphenylsiloxane) and / or a poly (methoxysiloxane), is. A coating composition according to any one of claims 17 or 18, characterized in that they in addition to the organosilicon polymer precursor at least one co-binder such. B. has an acrylate binder. Coating composition according to one of the preceding Claims, characterized in that they metallic particles, in particular Includes aluminum particles. Coating composition according to claim 20, characterized in that the stoichiometric ratio of metal particles: oxidizing agent and / or to oxidation catalyst> 1. Coating composition according to one of the preceding Claims, characterized in that it comprises at least one of the following components includes: - Particles with layer grid structure, - platelet-shaped particles and - Hard material particles. Coating composition according to one of the preceding Claims, characterized in that they contain conventional additives and / or dyes having. Coating composition according to one of the preceding Claims, characterized in that they substantially as solvent or suspending agent contains only water. Substrate, characterized in that it is a layer or a coating composition according to any one of the preceding claims having. Use of a composition according to one of previous claims to protect a substrate against corrosion, in particular by producing a Layer according to one of the preceding claims.