EP2619257A1

EP2619257A1 - Prepregs based on a storage-stable reactive or highly reactive polyurethane composition with a fixed film, and the composite component produced therefrom

Info

Publication number: EP2619257A1
Application number: EP11757214.9A
Authority: EP
Inventors: Friedrich Georg Schmidt; Sandra Reemers; Arnim Kraatz
Original assignee: Evonik Degussa GmbH
Current assignee: Evonik Operations GmbH
Priority date: 2010-09-23
Filing date: 2011-08-30
Publication date: 2013-07-31
Also published as: AU2011304537A1; AU2011304537B2; DE102010041256A1; CA2811665A1; TW201226454A; KR20140002633A; BR112013006856A2; WO2012038201A1; US20130230716A1; RU2013118434A; CN103210022A; JP2013544899A; MX2013003170A

Abstract

The invention relates to prepregs based on a storage-stable reactive or highly reactive polyurethane composition with a fixed film and to the composite component produced therefrom.

Description

Prepregs based on storage-stable reactive or highly reactive

Polyurethane composition with a fixed film and the product made therefrom

Composite component The invention relates to prepregs based on storage-stable reactive or highly reactive

Polyurethane composition with a fixed film and the composite component produced therefrom.

State of the art

Many composite matrix materials are not weather resistant or UV stable, or exhibit inadequate in conjunction with the glass or carbon fiber fabrics or facing

Surface quality. Therefore, composite components are often post-coated to achieve a particular surface finish in terms of smoothness, color, texture or other desired properties.

Composite (molded parts) made of fiber composite materials are painted to finish or color the surfaces. In most cases, the coating is done by painting the components, as well as highly automated with SMC components in the production of

Body parts done. Unfortunately, this is often associated with numerous defects (due to the relatively high porosity of the composite components compared to injection molded parts) and rejects. Surface sealing primers can at least partially overcome these problems, however, these pretreatments are costly and often associated with increased VOC (volatile organic compounds) emissions.

The painting is very complex because associated with high workload.

In the article by Achim Grefenstein "Film Injection Instead of Painting", in Metal Surface - Coating of Plastic and Metal, Issue 10/99, Carl Hanser Verlag, Munich, it is described to use films for surface finishing in the injection molding technology. The films are preformed and placed in an injection mold. Thereafter, the film is back-injected with plastic, and thus obtained the desired surface of the composite.

DE 103 09 81 1 describes a method in which a preformed film is placed in a mold such that a fiber-reinforced prepreg, for. B. with a thermoset or Thermoplastic matrix, with one on which the side of the preformed film is applied, and that after curing and cooling of the plastic of the fiber-reinforced prepreg, the finished composite of the mold is removed. The fixing of a film on the surface of the composite can be done with the film-backpressing or the film-resin-transfer-molding (film RTM). In this case, a preformed film is placed on one of the forming tools of a press, placed the fibrous carrier in the form of a mat on the counterpart of the tool of the press and connected with a tailored to the composition of this semi-finished pressing the preformed film with the carrier.

The film resin transfer molding (film RTM) takes place in a closed mold, which is comparable to the closed pressing tools, die and male, a press. In the mold, the preformed film and under its cavity a fiber mat, so only the

Fiber reinforcement, inserted. The evacuated mold is filled in a known manner with a mixture of resin and hardener, the mat is soaked and the cavity is filled under the film. The mold remains closed until the injected resin has cured. In open processes such as hand lamination or vacuum process, this technique is also conceivable. Such a method is known, for example, from EP 0 819 516.

Another method of surface finishing is a special form of IMD (In-Mold-Decoration). Here, a printed carrier film is passed over a mold. After closing the mold halves, the carrier film is transformed together with the decorative imprint by means of the pressure of an injected plastic. After hardening of the plastic and the removal of the component, the decor pressure adheres to the resulting component, then the carrier film is separated.

In EP 1 230 076 a method for applying a film by film forming in the forming tool is described.

From EP 2 024 164 a "one shot" method is known. In this case, a mat-shaped semi-finished product of binder-containing fiber materials is strongly heated and then in a press (and Although preferably in a so-called "cold press") connected to a decorative material (a lamination) and simultaneously formed.

From EP 1 669 182 a method and an apparatus for the production of compound molded parts is known. In the production of single-layer or multi-layer films (skins) or compound moldings in which at least one layer consists of reactive plastic, this layer is applied by spraying into a cavity or onto a substrate.

A coating of the composite components with Liquid Gel Coats already in the mold or the use of thermoplastic (multilayer) films via a comolding is also described [Jn-Mold Decoration Dresses Up Composites, Dale Brosius, Composites

Technology, Aug. 2005]. A fiber composite material is already known from EP 590 702, wherein a flexible film of a thermoplastic polymer covers a multifiber filament impregnated with a powder. The powder has as an essential component thermoplastic polymers. As a result, the fiber composite material should have a high flexibility, in particular for the formation of highly flexible mats. Storage-stable PU compositions containing uretdione groups are not mentioned.

However, the methods described above all require the previous process of applying the film to the composite in a separate operation. Prepregs based on storage-stable reactive or highly reactive polyurethane compositions are known from DE 102009001793, DE 102009001806 and DE 10201029355. However, these have no film coating.

The task was to find new prepregs with a refined surface and to simplify the production of prepregs and composite components.

The object is achieved by a storage-stable, polyurethane-based prepreg having a film which is intimately bonded to the surface of the prepregs and which, for the required surface functionality, is already fixed to the surface during the production of the prepregs Film which produces the required surface functionality of the composite component, and which tolerates temperature conditions and pressure conditions in composite component production.

It has been found that the prepregs according to the invention can be used to simplify the production of PU composite components which have a colored, matt, particularly smooth, scratch-resistant or antistatically finished surface.

The invention relates to prepregs,

essentially made up of

A) at least one fiber-shaped carrier

and

B) at least one reactive or highly reactive polyurethane composition as

Matrix material,

wherein the polyurethane compositions essentially mixtures of a polymer having isocyanate-reactive functional groups b) as a binder and internally blocked and / or blocked with blocking agents di- or

Polyisocyanate as hardener a),

C) at least one film fixed on the prepreg by the polyurethane composition B). The preparation of the prepregs can be done in principle by any method.

Suitably, a powdered polyurethane composition is passed through

Powder impregnation, preferably applied to the carrier by a scattering process. Also possible are vortex sintering, pultrusion, or spraying. The powder (total or fraction) is preferably spread over the fiber-shaped carrier, for. B. on webs of glass, carbon, or aramid fiber fabric or fiber fabric, applied and then fixed. In order to avoid powder losses, the fiber-shaped carrier, which is acted upon with powder, is preferably heated directly after the scattering process in a heating section (eg with IR emitters) so that the particles are sintered, whereby temperatures of 80 to 100 ° C. are not exceeded should be to areact the highly reactive

Prevent matrix material. These prepregs can be combined and cut to different shapes as needed. The prepregs can also be produced by the direct melt impregnation method. The principle of the direct melt impregnation method of the prepregs is that first a reactive polyurethane composition B) of their individual

Components is manufactured. This melt of the reactive polyurethane composition B) is then applied directly to the fiber-shaped carrier A), that is, there is an impregnation of the fiber-shaped carrier A) with the melt of B). Thereafter, the cooled, storable prepregs can be composites at a later date

be further processed. By direct melt impregnation method according to the invention is a very good impregnation of the fiber-shaped carrier, due to the fact that the liquid low viscous reactive polyurethane compositions wet the fiber of the carrier very well.

The prepregs can also be produced by means of a solvent. The principle of the process for producing prepregs is then that first a solution of the reactive polyurethane composition B) is prepared from their individual components in a suitable common solvent. This solution of the reactive

Polyurethane composition B) is then applied directly to the fiber-shaped carrier A), wherein the fiber-shaped carrier is impregnated / impregnated with this solution. Subsequently, the solvent is removed. Preferably, the solvent is completely at low temperature, preferably <100 ° C, by e.g. thermal treatment or

Vacuum application removed. Thereafter, the reusable prepregs freed from the solvent can be further processed into composites at a later time. By the method according to the invention, a very good impregnation of the fiber-shaped carrier, due to the fact that the solutions of the reactive polyurethane compositions very well wet the fiber of the carrier.

Suitable aprotic solvents for the process according to the invention are any aprotic

Liquids are used that are not reactive to the reactive ones

Polyurethane compositions are sufficient dissolving power against the used individual components of the reactive polyurethane composition and in the process step of the solvent removal to small traces (<0.5% by weight) can be deducted from the impregnated with the reactive polyurethane composition prepreg, wherein a recycling of the separated solvent is advantageous. Examples include: ketones (acetone, methyl ethyl ketone,

Methyl isobutyl ketone, cyclohexanone), ether (tetrahydrofuran), esters (n-propyl acetate, n-butyl acetate, isobutyl acetate, 1,2-propylene carbonate, propylene glycol methyl ether acetate).

The prepregs according to the invention are preferably prepared by this solvent process.

After cooling to room temperature, the prepregs according to the invention have a very high storage stability at room temperature as soon as the matrix material has a Tg of at least 40 ° C. This is at least a few days at room temperature, depending on the reactive polyurethane composition contained, but typically the prepregs are shelf stable for several weeks at 40 ° C and below. The prepregs produced in this way are not sticky and therefore very easy to handle and continue to process. The reactive or highly reactive polyurethane compositions used according to the invention therefore have a very good adhesion and distribution on the fiber-shaped carrier.

During the further processing of prepregs to composites z. B. by pressing at elevated temperatures, there is a very good impregnation of the fiber-shaped carrier, due to the fact that the liquid low viscous reactive or highly reactive polyurethane compositions before the crosslinking reaction wet the fiber of the carrier very well before by the crosslinking reaction of the reactive or highly reactive Polyurethane composition at elevated temperatures, a gelling occurs or cures the complete polyurethane matrix.

The prepregs produced in this way can be combined and cut to different shapes as needed.

To consolidate the prepregs into a single composite and to crosslink the matrix material to the matrix, the prepregs are cut, optionally sewn or otherwise fixed and pressed in a suitable mold under pressure and, if appropriate, by applying a vacuum. In the context of this invention, this process of producing the composites from the prepregs takes place depending on the curing time at temperatures above about 160 ° C when using reactive matrix materials (variant I), or provided with appropriate catalysts highly reactive matrix materials (variant II) at temperatures of over 100 ° C. Depending on the composition of the used reactive or highly reactive

Polyurethane composition and optionally added catalysts, both the speed of the crosslinking reaction in the production of the composite components and the properties of the matrix can be varied within wide ranges.

In the context of the invention, the reactive or highly reactive polyurethane composition used for producing the prepregs is defined as matrix material, and in the description of the prepregs, the still reactive or highly reactive polyurethane composition applied to the fiber by the process according to the invention.

The matrix is defined as the composite crosslinked matrix materials from the reactive or highly reactive polyurethane compositions.

carrier

The fiber-shaped carrier in the present invention consists of fiber-shaped material (also often called reinforcing fibers). In general, any material that makes up the fibers is suitable, but fiber-shaped material made of glass is preferred,

Carbon, plastics, such. As polyamide (aramid) or polyester, natural fibers or mineral fiber materials such as basalt fibers or ceramic fibers (oxide fibers based on aluminum oxides and / or silicon oxides) used. Also mixtures of fiber types, such as. B. fabric combinations of aramid and glass fibers, or carbon and glass fibers can be used. Likewise, hybrid composite components with prepregs of different fiber-shaped carriers can be produced. Glass fibers are the most commonly used fiber types mainly because of their relatively low price. In principle, here are all types of glass-based

Reinforcing fibers suitable (E-glass, S-glass, R-glass, M-glass, C-glass, ECR-glass, D-glass, AR-glass, or hollow glass fibers). Carbon fibers generally come in

High-performance composites are used, where the lower density in relation to the glass fiber and at the same time high strength is an important factor. Carbon fibers (also carbon fibers) are industrially produced carbon-containing fibers

Starting materials that are converted by pyrolysis into graphitic carbon. A distinction is made between isotropic and anisotropic types: isotropic fibers have only low strength and less technical importance, anisotropic fibers show high Strengths and stiffness with low elongation at break. Natural fibers are here all textile fibers and fiber materials, which are derived from vegetable and animal material (eg., Wood, cellulose, cotton, hemp, jute, linen, sisal, bamboo fibers). Similar to carbon fibers, aramid fibers have a negative coefficient of thermal expansion, ie become shorter when heated. Their specific strength and elastic modulus are significantly lower than that of carbon fibers. In conjunction with the positive expansion coefficient of the matrix resin can be manufactured dimensionally stable components. Compared to carbon fiber reinforced plastics, the compressive strength of aramid fiber composites is significantly lower. Known brand names for aramid fibers are Nomex® and Kevlar® from DuPont, or Teijinconex®, Twaron® and Technora® from Teijin. Particularly suitable and preferred are carriers made of glass fibers, carbon fibers, aramid fibers or ceramic fibers. The fiber-shaped material is a textile fabric. Suitable fabrics are nonwoven fabrics, as well as so-called knits, such as knitted fabrics and knits, but also non-meshed containers such as fabrics, scrims or braids. In addition, a distinction long fiber and short fiber materials as a carrier. Also suitable according to the invention are rovings and yarns. All materials mentioned are suitable in the context of the invention as a fiber-shaped carrier. An overview of reinforcing fibers can be found in "Composites Technologies, Paolo Ermanni (Version 4), Script for the lecture ETH Zurich, August 2007, Chapter 7".

matrix material

In principle, all, even other storage stable at room temperature reactive

Polyurethane compositions are suitable as matrix materials. suitable

Polyurethane compositions according to the invention consist of mixtures of a functional group - reactive with NCO groups - having polymers b) (binder), also referred to as resin, and temporarily deactivated, that is internally blocked and / or blocked with blocking agents di- or polyisocyanates, also as Hardener a) (component a)). Suitable functional groups of the polymers b) (binders) are hydroxyl groups, amino groups and thiol groups which react with the free isocyanate groups with addition and thus crosslink and harden the polyurethane composition. The binder components must have a solid resin character (glass transition temperature greater than room temperature). Suitable binders are polyesters, polyethers, polyacrylates, polycarbonates and polyurethanes with an OH number of 20 to 500 mg KOH / gram and an average molecular weight of 250 to 6000 g / mol. Particularly preferred are hydroxyl-containing polyesters or polyacrylates having an OH number of 20 to 150 mg KOH / gram and an average molecular weight of 500 to 6000 g / mol. Of course, mixtures of such polymers can be used. The amount of polymers b) containing the functional groups is selected such that each functional group of component b) contains 0.6 to 2 NCO equivalents or 0.3 to 1 uretdione group of component a).

As hardener component a) blocked or internally blocked (uretdione) di- and polyisocyanates are used with blocking agents.

The diisocyanates and polyisocyanates used according to the invention can be obtained from any desired

aromatic, aliphatic, cycloaliphatic and / or (cyclo) aliphatic di- and / or polyisocyanates.

As aromatic di- or polyisocyanates are in principle all known aromatic

Compounds suitable. Particularly suitable are 1, 3 and 1, 4-phenylene diisocyanate, 1, 5-naphthylene diisocyanate, tolidine diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate (2,4-TDI), 2,4'-diphenylmethane diisocyanate ( 2,4'-MDI), 4,4'-diphenylmethane diisocyanate, the mixtures of monomeric diphenylmethane diisocyanates (MDI) and oligomers

Diphenylmethane diisocyanates (polymer-MDI), xylylene diisocyanate,

Tetramethylxylylene diisocyanate and triisocyanatotoluene.

Suitable aliphatic di- or polyisocyanates advantageously have 3 to 16

Carbon atoms, preferably 4 to 12 carbon atoms, in the linear or branched alkylene radical and suitable cycloaliphatic or (cyclo) aliphatic diisocyanates

advantageously 4 to 18 carbon atoms, preferably 6 to 15 carbon atoms, in the cycloalkylene radical. Under (cyclo) aliphatic diisocyanates, the skilled worker understands at the same time cyclic and aliphatic bound NCO groups, as z. For example

Isophorone diisocyanate is the case. In contrast, is meant by cycloaliphatic diisocyanates those which have only directly attached to the cycloaliphatic ring NCO groups, for. B. H ₁₂ MDI. Examples are cyclohexane diisocyanate, methylcyclohexane diisocyanate, ethylcyclohexane diisocyanate, propylcyclohexane diisocyanate, methyldiethylcyclohexane diisocyanate, propane diisocyanate, butane diisocyanate, pentane diisocyanate, hexane diisocyanate, Heptane diisocyanate, octane diisocyanate, nonane diisocyanate, nonane triisocyanate, such as 4-isocyanatomethyl-1, 8-octane diisocyanate (TIN), decane and triisocyanate, undecanediol and triisocyanate, dodecane diisocyanates and triisocyanates. Preference is given to isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI),

Diisocyanatodicyclohexylmethane (H ₁₂ MDI), 2-methylpentane diisocyanate (MPDI), 2,2,4-trimethylhexamethylene diisocyanate / 2,4,4-trimethylhexamethylene diisocyanate (TMDI),

Norbornane diisocyanate (NBDI). Very particular preference is given to using IPDI, HDI, TMDI and / or H ₁₂ MDI, the isocyanurates also being usable. Also suitable are 4-methylcyclohexane-1, 3-diisocyanate, 2-butyl-2-ethylpentamethylene diisocyanate, 3 (4) - isocyanatomethyl-1-methylcyclohexylisocyanate, 2-isocyanatopropylcyclohexyl isocyanate, 2,4'-methylenebis (cyclohexyl ) diisocyanate, 1, 4-diisocyanato-4-methyl-pentane.

Of course, mixtures of di- and polyisocyanates can be used.

Furthermore, preference is given to using oligoisocyanates or polyisocyanates which are prepared from the abovementioned diisocyanates or polyisocyanates or mixtures thereof by linking by means of urethane, allophanate, urea, biuret, uretdione, amide, isocyanurate, carbodiimide, uretonimine , Oxadiazinetrione or iminooxadiazinedione structures. Particularly suitable are isocyanurates, especially from IPDI and / or HDI.

The polyisocyanates used in the invention are blocked. In question come to external blocking agents such. Ethyl acetoacetate, diisopropylamine,

Methyl ethyl ketoxime, diethyl malonate, ε-caprolactam, 1, 2,4-triazole, phenol or

substituted phenols and 3,5-dimethylpyrazole.

The preferred hardener components are IPDI adducts containing isocyanurate moieties and ε-caprolactam blocked isocyanate structures. An internal blocking is possible and this is preferably used. The internal blockage occurs via a dimer formation via uretdione structures, which at elevated

Cleave the temperature back into the original isocyanate structures and thus initiate the crosslinking with the binder. Optionally, the reactive polyurethane compositions may contain additional catalysts. These are organometallic catalysts, such as. B.

Dibutyltin dilaurate (DBTL), Zinnoctoat, bismuth neodecanoate, or tertiary amines, such as. B. 1, 4-diazabicyclo [2.2.2.] Octane, in amounts of 0.001 - 1 wt .-%. These reactive polyurethane compositions used in this invention are used under normal conditions, for. B. with DBTL catalysis, from 160 ° C, usually cured from about 180 ° C and designated as variant I.

For the preparation of the reactive polyurethane compositions, the in the

Powder coating technology customary additives, such as leveling agents, z. As polysilicone or acrylates, light stabilizers z. As sterically hindered amines, antioxidants, or other aids, such as. As described in EP 669 353, be added in a total amount of 0.05 to 5 wt .-%. Fillers and pigments such. Titanium dioxide may be added in an amount of up to 30% by weight of the total composition.

In the context of this invention, reactive (variant I) means that the reactive polyurethane compositions used according to the invention are as described above

Temperatures from 160 ° C, depending on the type of carrier cure. The reactive polyurethane compositions used in the invention are used under normal conditions, for. B. with DBTL catalysis, from 160 ° C, usually from about 180 ° C cured. The time for curing the inventively used

Polyurethane composition is usually within 5 to 60 minutes. A matrix material B) is preferably used in the present invention, from a polyurethane compositions B) containing reactive uretdione groups, essentially containing a) at least one curing agent containing uretdione groups, based on

Polyaddition compounds of aliphatic, (cyclo) aliphatic or cycloaliphatic uretdione groups containing polyisocyanates and hydroxyl-containing compounds, wherein the curing agent is below 40 ° C in solid form and above 125 ° C in liquid form and a free NCO content of less than 5 wt. % and a uretdione content of 3 - 25 wt .-%, b) at least one hydroxyl-containing polymer which is in liquid form below 40 ° C. in solid form and above 125 ° C. and has an OH number between 20 and 200 mg KOH / gram, c) if appropriate at least one catalyst, d) optionally known from polyurethane chemistry auxiliaries and additives, so that the two components a) and b) are present in the ratio that on each

Hydroxyl group of component b) 0.3 to 1 uretdione group of component a) is omitted, preferably 0.45 to 0.55. The latter corresponds to an NCO / OH ratio of 0.9 to 1, 1 to 1.

Uretdione group-containing polyisocyanates are well known and are described, for example, in US 4,476,054, US 4,912,210, US 4,929,724 and EP 417,603. A comprehensive review of industrially relevant processes for the dimerization of isocyanates to uretdiones is provided by J. Prakt. Chem. 336 (1994) 185-200. In general, the reaction of isocyanates to uretdiones in the presence of soluble dimerization catalysts such. B.

Dialkylaminopyridinen, trialkylphosphines, Phosphorigsäuretriamiden or imidazoles. The reaction - optionally carried out in solvents, but preferably in the absence of solvents - is stopped when a desired conversion is achieved by addition of catalyst poisons. Excess monomeric isocyanate is followed by

Short path evaporation separated. If the catalyst is volatile enough, that can

Be removed reaction mixture in the course of monomer removal from the catalyst. The addition of catalyst poisons can be dispensed with in this case. Basically, a wide range of. Is to produce polyisocyanates containing uretdione groups

Isocyanates suitable. The above di- and polyisocyanates can be used. However, preference is given to diisocyanates and polyisocyanates of any aliphatic,

cycloaliphatic and / or (cyclo) aliphatic di- and / or polyisocyanates.

According to the invention, isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), diisocyanatodicyclohexylmethane (H ₁₂ MDI), 2-methylpentane diisocyanate (MPDI), 2,2,4-trimethylhexamethylene diisocyanate / 2,4,4-trimethylhexamethylene diisocyanate (TMDI),

Norbornane diisocyanate (NBDI) used. Very particular preference is given to using IPDI, HDI, TMDI and / or H ₁₂ MDI, the isocyanurates also being usable. Most preferably, IPDI and / or HDI are used for the matrix material. The implementation of these polyisocyanates containing uretdione groups to uretdione group-containing hardeners a) involves the reaction of the free NCOGruppen with hydroxyl-containing monomers or polymers, such as. As polyesters, polythioethers, polyethers,

Polycaprolactams, polyepoxides, polyester amides, polyurethanes or lower molecular weight di-, tri- and / or tetra alcohols as chain extenders and optionally monoamines and / or monoalcohols as chain terminators and has been described frequently (EP 669 353, EP 669 354, DE 30 30 572, EP 639 598 or EP 803 524). Preferred uretdione hardeners a) have a free NCO content of less than 5 wt .-% and a content of uretdione groups from 3 to 25 wt .-%, preferably 6 to 18 wt .-% (calculated as C ₂ N ₂ 0 ₂ , molecular weight 84). Preference is given to polyesters and monomeric dialcohols. In addition to the uretdione groups, the hardeners may also have isocyanurate, biuret, allophanate, urethane and / or urea structures.

In the case of the hydroxyl-containing polymers b), preference is given to using polyesters, polyethers, polyacrylates, polyurethanes and / or polycarbonates having an OH number of 20-200 in mg KOH / gram. Particular preference is given to using polyesters having an OH number of 30-150, an average molecular weight of 500-6000 g / mol, which are below 40 ° C. in solid form and above 125 ° C. in liquid form. Such binders have been described, for example, in EP 669 354 and EP 254 152. Of course, mixtures of such polymers can be used. The amount of the

hydroxyl-containing polymers b) is chosen so that each hydroxyl group of component b) 0.3 to 1 uretdione group of component a), preferably 0.45 to 0.55, is omitted. Optionally, in the reactive polyurethane compositions B) according to the invention, additional catalysts c) may be present. These are organometallic catalysts, such as. As dibutyltin dilaurate, zinc octoate, bismuth neodecanoate, or tertiary amines, such as. B. 1, 4-diazabicyclo [2.2.2.] Octane, in amounts of 0.001 - 1 wt .-%. These reactive polyurethane compositions used in this invention are used under normal conditions, for. B. with DBTL catalysis, from 160 ° C, usually cured from about 180 ° C and designated as variant I.

For the preparation of the reactive polyurethane compositions according to the invention, the customary in the powder coating technology additives d) as leveling agents, for. B. polysilicone or acrylates, light stabilizers z. As sterically hindered amines, antioxidants, or other auxiliaries, such as. As described in EP 669 353, be added in a total amount of 0.05 to 5 wt .-%. Fillers and pigments such. Titanium dioxide may be added in an amount of up to 30% by weight of the total composition.

The reactive polyurethane compositions used in the invention are used under normal conditions, for. B. with DBTL catalysis, from 160 ° C, usually from about 180 ° C cured. The reactive polyurethane compositions used according to the invention have a very good flow and thus a good impregnation ability and in the cured state an excellent chemical resistance. When using aliphatic crosslinkers (eg IPDI or H12MDI), a good weather resistance is additionally achieved.

Particularly preferred in the invention, a matrix material is used

out

B) containing at least one highly reactive uretdione-containing polyurethane composition, substantially containing

a) at least one hardener containing uretdione groups

and

b) optionally at least one polymer having NCO-reactive functional groups;

c) 0.1 to 5 wt .-% of at least one catalyst selected from quaternary

Ammonium salts and / or quaternary phosphonium salts with halogens,

Hydroxides, alcoholates or organic or inorganic acid anions as counterion;

and

d) 0.1 to 5 wt .-% of at least one co-catalyst selected from

d1) at least one epoxide

and or

d2) at least one metal acetylacetonate and / or quaternary

Ammonium acetylacetonate and / or quaternary phosphonium acetylacetonate; e) optionally known from polyurethane chemistry auxiliaries and additives.

In particular, a matrix material B) is used containing at least one highly reactive powdered Uretdiongruppen

Polyurethane composition as matrix material, substantially containing

a) at least one hardening agent containing uretdione groups, based on

Polyadditionsverbindungen of aliphatic, (cyclo) aliphatic or

cycloaliphatic uretdione groups contained polyisocyanates and

hydroxyl-containing compounds, wherein the hardener is below 40 ° C. in solid form and above 125 ° C. in liquid form and has a free NCO content of less than 5% by weight and a uretdione content of 3 to 25% by weight, b) at least one hydroxyl-containing polymer which is in liquid form below 40 ° C in solid form and above 125 ° C and has an OH number between 20 and 200 mg KOH / gram;

c) 0.1 to 5 wt .-% of at least one catalyst selected from quaternary

Ammonium salts and / or quaternary phosphonium salts with halogens,

Hydroxides, alcoholates or organic or inorganic acid anions as counterion;

I

d) 0.1 to 5 wt .-% of at least one co-catalyst selected from

d1) at least one epoxide

and or

d2) at least one metal acetylacetonate and / or quaternary

Ammonium acetylacetonate and / or quaternary phosphonium acetylacetonate; e) optionally known from polyurethane chemistry auxiliaries and additives, so that the two components a) and b) are present in the ratio that on each

Hydroxyl group of component b) 0.3 to 1 uretdione group of component a) is omitted, preferably 0.6 to 0.9. The latter corresponds to an NCO / OH ratio of 0.6 to 2 to 1 or 1, 2 to 1, 8 to 1. These inventively used highly reactive

Polyurethane compositions are cured at temperatures of 100 to 160 ° C and referred to as variant II.

According to the invention, suitable highly reactive uretdione-containing polyurethane compositions comprise mixtures of temporarily deactivated, ie uretdione-containing (internally blocked) di- or polyisocyanates, also referred to as hardeners a), and the catalysts c) and d) present in the invention and optionally additionally a functional one Groups - polymer reactive to NCO groups - (Binder), also referred to as Resin b). The catalysts ensure curing of the uretdione-group-containing polyurethane compositions at low temperature. Contain the uretdione groups

Polyurethane compositions are thus highly reactive.

Hardeners component a) and component b) containing uretdione groups are used as described above.

As catalysts under c) quaternary ammonium salts are preferred

Tetralkylammoniumsalze and / or quaternary phosphonium salts with halogens, hydroxides, alcoholates or organic or inorganic acid anions as counterion used. Examples are:

Tetramethylammonium, tetramethylammonium, Tetramethylammoniumpropionat, Tetramethylammoniumbutyrat, tetramethylammonium benzoate, tetraethylammonium, tetraethylammonium, Tetraethylammoniumpropionat, Tetraethylammoniumbutyrat, tetraethylammonium, Tetrapropylammoniumformiat, Tetrapropylammoniumacetat, Tetrapropylammoniumpropionat, Tetrapropylammoniumbutyrat, Tetrapropylammoniumbenzoat, tetrabutylammonium, tetrabutylammonium, Tetrabutylammoniumpropionat, Tetrabutylammoniumbutyrat and tetrabutylammonium benzoate and

Tetrabutylphosphonium acetate, tetrabutylphosphonium formate and

Ethyltriphenylphosphonium acetate, tetrabutylphosphonium benzotriazolate,

Tetraphenylphosphonium phenolate and trihexyltetradecylphosphonium decanoate,

Methyltributylammonium hydroxide, methyltriethylammonium hydroxide,

Tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, tetradecylammonium hydroxide,

Tetradecyltrihexylammonium hydroxide, tetraoctadecylammonium hydroxide,

Benzyltrimethylammonium hydroxide, benzyltriethylammonium hydroxide, trimethylphenylammonium hydroxide, triethylmethylammonium hydroxide, trimethylvinylammonium hydroxide, methyltributylammonium methoxide,

Methyltriethylammonium methoxide, tetramethylammonium methoxide,

Tetraethylammonium methoxide, tetrapropylammonium methoxide,

Tetrabutylammonium methoxide, tetrapentylammonium methoxide,

Tetrahexylammonium methoxide, tetraoctylammonium methoxide, Tetradecylammonium methoxide, tetradecyltrihexylammonium methoxide,

Tetraoctadecylammonium methoxide, benzyltrimethylammonium methoxide,

Benzyltriethylammonium methoxide, trimethylphenylammonium methoxide,

Triethylmethylammonium methoxide, trimethylvinylammonium methoxide,

Methyltributylammoniumethanolate, methyltriethylammoniumethanolate,

Tetramethylammoniumethanolate, tetraethylammoniumethanolate,

Tetrapropylammonium ethanolate, tetrabutylammonium ethanolate,

Tetrapentylammoniumethanolate, tetrahexylammoniumethanolate,

Tetraoctylammonium methoxide, tetradecylammonium ethanolate,

Tetradecyltrihexylammoniumethanolate, tetraoctadecylammoniumethanolate,

Benzyltrimethylammoniumethanolate, benzyltriethylammoniumethanolate,

Tri-methylphenylammoniumethanolate, triethylmethylammoniumethanolate,

Tri-methylvinylammoniumethanolate, methyltributylammoniumbenzylate,

Methyltriethylammonium benzylate, tetramethylammonium benzylate,

Tetraethylammonium benzylate, tetrapropylammonium benzylate, tetrabutylammonium benzylate,

Tetrapentylammonium benzylate, tetrahexylammonium benzylate, tetraoctylammonium benzylate,

Tetradecylammonium benzylate, tetradecyltrihexylammoniumbenzylate,

Tetraoctadecylammonium benzylate, benzyltrimethylammonium benzylate,

Benzyltriethylammonium benzylate, tri-methylphenylammoniumbenzylate,

Triethylmethylammonium benzylate, tri-methylvinylammonium benzylate,

Tetramethylammonium fluoride, tetraethylammonium fluoride, tetrabutylammonium fluoride,

Tetraoctylammonium fluoride, benzyltrimethylammonium fluoride, tetrabutylphosphonium hydroxide,

Tetrabutylphosphonium fluoride, tetrabutylammonium chloride, tetrabutylammonium bromide,

Tetrabutylammonium iodide, tetraethylammonium chloride, tetraethylammonium bromide,

Tetraethylammonium iodide, tetramethylammonium chloride, tetramethylammonium bromide,

Tetramethylammonium iodide, benzyltrimethylammonium chloride, benzyltriethylammonium chloride,

Benzyltripropylammonium chloride, benzyltributylammonium chloride,

Methyltributylammonium chloride, methyltripropylammonium chloride,

Methyltriethylammonium chloride, methyltriphenylammonium chloride,

Phenyltrimethylammonium chloride, benzyltrimethylammonium bromide,

Benzyltriethylammonium bromide, benzyltripropylammonium bromide,

Benzyltributylammonium bromide, methyltributylammonium bromide,

Methyltripropylammonium bromide, methyltriethylammonium bromide,

Methyltriphenylammonium bromide, phenyltrimethylammonium bromide, Benzyltrimethylammonium iodide, benzyltriethylammonium iodide, benzyltripropylammonium iodide, benzyltributylammonium iodide, methyltributylammonium iodide, methyltripropylammonium iodide, methyltriethylammonium iodide, methyltriphenylammonium iodide and

Phenyltrimethylammonium iodide, methyltributylammonium hydroxide,

Methyltriethylammonium hydroxide, tetramethylammonium hydroxide,

Tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide, tetrapentylammonium hydroxide, tetrahexylammonium hydroxide, tetraoctylammonium hydroxide, tetradecylammonium hydroxide, tetradecyltrihexylammonium hydroxide,

Tetraoctadecylammonium hydroxide, benzyltrimethylammonium hydroxide,

Benzyltriethylammonium hydroxide, trimethylphenylammonium hydroxide,

Triethylmethylammonium hydroxide, trimethylvinylammonium hydroxide,

Tetramethylammonium fluoride, tetraethylammonium fluoride, tetrabutylammonium fluoride, tetraoctylammonium fluoride and benzyltrimethylammonium fluoride. These catalysts may be added alone or in mixtures. Preference is given to using tetraethylammonium benzoate and / or tetrabutylammonium hydroxide.

The proportion of catalysts c) may be from 0.1 to 5% by weight, preferably from 0.3 to 2% by weight, based on the total formulation of the matrix material. A variant according to the invention includes the attachment of such catalysts c) to the functional groups of the polymers b). In addition, these catalysts may be surrounded with an inert shell and encapsulated with it.

As co-catalysts d1) epoxides are used. In question come here z. B.

Glycidyl ethers and glycidyl esters, aliphatic epoxides, diglycidyl ethers based on bisphenol A and glycidyl methacrylates. Examples of such epoxides are triglycidyl isocyanurate (TGIC,

Trade name ARALDIT 810, Huntsman), mixtures of terephthalic acid diglycidyl ester and trimellitic triglycidyl ester (trade name ARALDIT PT 910 and 912, Huntsman), glycidyl ester of versatic acid (trade name KARDURA E10, Shell), 3,4-epoxycyclohexylmethyl-3 ', 4'-epoxyeyclohexanecarboxylate (ECC) , Diglycidyl ether based on bisphenol A (trade name

EPIKOTE 828, Shell) ethylhexyl glycidyl ether, butyl glycidyl ether, pentaerythritol tetraglycidyl ether (trade name POLYPOX R 16, UPPC AG) as well as other types of polypoets with free

Epoxy groups. It can also be used mixtures. Preference is given to using ARALDIT PT 910 and 912 used. Suitable cocatalysts d2) are metal acetylacetonates. Examples are

Zinc acetylacetonate, lithium acetylacetonate and tin acetylacetonate, alone or in mixtures. Zinc acetylacetonate is preferably used. Also suitable as cocatalysts d2) are quaternary ammonium acetylacetonates or quaternary phosphonium acetylacetonates.

Examples of such catalysts are tetramethylammonium acetylacetonate,

Tetraethylammonium acetylacetonate, tetrapropylammonium acetylacetonate,

Tetrabutylammonium acetylacetonate, benzyltrimethylammonium acetylacetonate,

Benzyltriethylammonium acetylacetonate, tetramethylphosphonium acetylacetonate,

Tetraethylphosphonium acetylacetonate, tetrapropylphosphonium acetylacetonate,

Tetrabutylphosphonium acetylacetonate, benzyltrimethylphosphonium acetylacetonate,

Benzyltriethylphosphoniumacetylacetonat. Particularly preferred

Tetraethylammoniumacetylacetonat and / or tetrabutylammonium acetylacetonate used. Of course, mixtures of such catalysts can be used.

The proportion of cocatalysts d1) and / or d2) can be from 0.1 to 5% by weight, preferably from 0.3 to 2% by weight, based on the total formulation of the matrix material.

With the help of the inventively used highly reactive and thus at low temperature curing polyurethane compositions B) can at 100 to 160 ° C.

Curing temperature not only saves energy and curing time, but it can also use many temperature-sensitive carrier.

Highly reactive (variant II) in the context of this invention means that the uretdione group-containing polyurethane compositions used according to the invention cure at temperatures of 100 to 160 ° C, depending on the nature of the carrier. Preferably, this is

Curing temperature 120 to 150 ° C, more preferably from 130 to 140 ° C. The time for curing the polyurethane composition used according to the invention is within 5 to 60 minutes.

Contain the highly reactive Urediongruppen used in the invention

Polyurethane compositions provide a very good flow and thus a good Impregnation and in the cured state an excellent

Chemical resistance. When using aliphatic crosslinkers (eg IPDI or H ₁₂ MDI), a good weathering resistance is additionally achieved. The preparation of the Matixmaterials can be carried out as follows: The homogenization of all components for the preparation of the polyurethane composition B) can be carried out in suitable aggregates, such as. As heated stirred tanks, kneaders, or extruders, carried out, with upper temperature limits of 120 to 130 ° C should not be exceeded. The mixture of the individual components is preferably carried out in an extruder at temperatures which, although above the melting ranges of the individual components, but below the

Temperature at which the crosslinking reaction starts. The use directly from the melt or after cooling and production of a powder is then possible. The production of

Polyurethane composition B) can also be carried out in a solvent by mixing in the abovementioned aggregates.

Subsequently, we processed the matrix material B) depending on the method with the carrier A) and the film C) to the prepregs.

The reactive or highly reactive used according to the invention as a matrix material

Polyurethane compositions essentially consist of a mixture of a reactive resin and a hardener. This mixture has a Tg of at least 40 ° C after a melt homogenization and usually reacts only above 160 ° C, in the reactive polyurethane compositions, or above 100 ° C in the highly reactive polyurethane compositions to form a crosslinked polyurethane and thus forms the matrix of Composites. This means that the prepregs of the invention after their preparation from the carrier and the applied reactive polyurethane composition as

Matrix material, which is present in uncrosslinked but reactive form, are constructed.

The prepregs are thus stable in storage, usually several days and even weeks and can thus be further processed into composites at any time. This is the essential difference to the two-component systems already described above, which are reactive and not storage-stable, since they immediately begin to react and crosslink after application to polyurethanes. The prepregs according to the invention and the composite components have a fiber volume fraction of greater than 50%, preferably greater than 50-70%, particularly preferably from 50 to 65%. Laminated films based on thermoplastics or their mixtures or compounds, for example of thermoplastic polyurethanes (TPU), thermoplastic polyolefins (TPO), (meth) acrylic polymers, polycarbonate films (eg Lexan SLX from Sabic Innovative Plastics), can be used as (multilayer) films. Polyamides, polyetheresteramides, polyetheramides, polyvinylidene difluoride (eg SOLIANT FLUOREX films from SOLIANT, AkzoNobel or AVLOY from Avery) or metallized or metallic films such as aluminum, copper or other materials, with adhesion to both the reactive or highly reactive uretdione group-containing matrix systems already done in the production of prepregs. In addition, in addition to the further processing of the prepregs to the cured polyurethane laminate surfaces of the composite, a further fixation of the film. The laminating films based on thermoplastic materials can be dyed as a whole by pigments and / or dyes as well as printed or painted on the outer surface.

The laminating film has a thickness between 0.2 and 10 mm, preferably between 0.5 and 4 mm. The softening point is between 80 and 260 ° C, preferably between 1 10 and 180 ° C, more preferably between 130 and 180 ° C for the storage-stable highly reactive

Polyurethane compositions and between 130 and 220 ° C for the reactive

Polyurethane compositions, and more preferably between 160 and 220 ° C. Suitable films are e.g. also described in WO 2004/067246.

The fixing of the laminating film on the prepreg is carried out according to the invention directly in the preparation of the prepreg. In this case, the fixation of the film by the adhesion through the matrix, exemplified shown in Figure 1, by laminating the prepreg in situ at drying temperatures of the prepreg (sub-crosslinking temperatures which denotes the temperature at which the crosslinking of the matrix material is not yet used). In general, this fixation is carried out at temperatures of 50 to 1 10 ° C. The fixing of the laminating film on the prepreg can also be carried out by first preparing a prepreg in a first step and, in a second step, applying and fixing the film to the prepreg which has already been prepared separately. This results in the fixation of the film by the adhesion through the matrix, exemplified shown in Figure 2, by laminating the prepreg at drying temperatures of the prepreg (sub-crosslinking temperatures). In general, this fixation is carried out at temperatures of 50 to 1 10 ° C.

The storage-stable prepregs provided in this way with laminating films can also be combined with further prepregs (unbacked) into laminates or to sandwich components by means of suitable methods, e.g. Autoclave or Pressmold process are processed, see Figure 3.

An alternative to the use of a laminating film is the separate production of a decorative coating layer or film, from the same or formulation-like material based on reactive or highly reactive polyurethane compositions B), with which the storage-stable prepregs of the invention are prepared.

A further alternative (and embodiment of the invention) of a prepreg according to the invention has a special surface quality due to a significantly increased matrix-to-fiber ratio. It therefore has a very low fiber volume fraction. For a particularly smooth and / or colored composite component surface is in this embodiment a

Fiber volume fraction of <50%, preferably <40%, more preferably <35% set. The exemplary preparation of such a prepreg is shown in FIG. The production of the laminated prepregs or the double-layer prepregs according to the invention can be effected by means of the known systems and apparatuses according to Reaction Injection Molding (RIM), Reinforced Reaction Injection Molding (RRIM), pultrusion processes, by application of the solution in a roll mill or by means of a hot doctor blade , or other procedures are performed.

The invention also relates to the use of prepregs, in particular with fiber-shaped carriers made of glass, carbon or aramid fibers. The invention also provides the use of the prepregs according to the invention, for the production of composites in boat and shipbuilding, in aerospace engineering, in the automotive industry, for two-wheelers, preferably motorcycles and bicycles, in the areas

Automotive, Construction, Medical, Sports, Electrical and Electronics,

Power generation plants, eg. B. for rotor blades in wind turbines.

The invention also relates to the composite components produced from the prepregs according to the invention. Depending on the nature of the film, the finished composite components produced from the prepregs according to the invention have a colored, matt, particularly smooth, scratch-resistant or antistatically finished surface.

Examples Fiberglass scrims and fiberglass fabrics used:

The following fiberglass scrims and fiberglass scrims were used in the Examples, hereafter referred to as Type I and Type II.

Type I is a canvas E-glass fabric 281 L, article No. 3103 of the company "Schlösser &Cramer" The fabric has a basis weight of 280 g / m ² .

Type II GBX 600 Art.No. 1023 is a sewn biaxial E-glass-clutches (-45 / + 45) of the company "Schlösser &Cramer", which means two layers of fiber bundles, which lie one above the other and are offset at an angle of 90 degrees This structure is held together by other fibers which are not made of glass, however.The surface of the glass fibers is equipped with a standard sizing which is aminosilane-modified The scrim has a basis weight of 600 g / m ² .

Reactive polyurethane composition

A reactive polyurethane composition having the following formulation was used to make the prepregs and composites. Example 1 Formulation [Variant I]

(Invention)

in% by weight

VESTAGON BF 9030 26.8

(uretdione group-containing hardener component

a)), Evonik Degussa

FINEPLUS PE 8078 VKRK20 (OH-72.7

functional polyester resin component b)),

Company DIC

Flow additive BYK 361 N 0.5

NCO: OH ratio 1: 1

The comminuted starting materials from the table and the dyes and / or pigments are intimately mixed in a premixer and then homogenized in the extruder to a maximum of 130 ° C. Thereafter, this reactive polyurethane composition can be used to prepare the prepregs depending on the manufacturing method. This reactive

Polyurethane composition can then be used after milling to prepare the prepregs after the powder impregnation process. For the direct melt impregnation method, the homogenized melt mixture produced in the extruder can be used directly.

Highly reactive polyurethane composition

A highly reactive polyurethane composition having the following formulation was used to make the prepregs and composites.

Example II Formulation [Variant II]

(Invention)

in% by weight

VESTAGON BF 9030 (uretdione group-containing 33.05

Hardener component a)), Evonik Degussa

5

FINEPLUS PE 8078 VKRK20 (OH-functional 63,13

Polyester resin component b)), DIC company

BYK 361 N 0.5

Vestagon SC 5050, tetraethylammonium benzoate 1, 52

containing catalyst c)), Evonik Degussa 10

Araldit PT 912, (epoxy component d)), Huntsman 1, 80

NCO: OH ratio 1, 4: 1

The comminuted feedstocks from the table and the dyes and / or pigments are intimately mixed in a pre-mixer and then homogenized in the extruder to a maximum of 1 10 ° C. Thereafter, this reactive polyurethane composition can be used to prepare the prepregs depending on the manufacturing method.

Production of prepregs

The preparation of the prepregs by means of direct melt impregnation method according to DE 102010029355.

The fixing of the films takes place directly after the melt impregnation of the fibrous carrier, wherein care is taken that the, when fixing the film on the prepreg existing temperature of the impregnated matrix material between 5 and 20 ° C above the glass transition temperature of the film, so Adhesion between film and prepreg when pressed.

The films used are, for example, FLUOREX 2010 (ABS support material) (Soliant) or SENOTOP films (Senoplast GmbH). The Senotop film itself consists of several coextruded layers of thermoplastic material and is characterized by a Class A surface. DSC measurements

The DSC investigations (glass transition temperature determinations and

Reaction enthalpy measurements) are detected with a Mettler Toledo DSC 821 e

DIN 53765 performed

Storage stability of the prepregs

The storage stability of the prepregs was determined on the basis of the glass transition temperatures and the reaction enthalpies of the crosslinking reaction by means of DSC investigations.

The cross-linking ability of the PU prepregs is not affected by storage at room temperature for a period of 7 weeks.

Composite device manufacturing

The composite components are produced by means of a pressing technique known to the person skilled in the art on a composite press. The homogeneous prepregs produced by means of direct melt impregnation were pressed on a table press into composite materials. This tabletop press is the Polystat 200 T from Schwabenthan, which presses the prepregs at temperatures between 120 and 200 ° C into the appropriate composite plates. The pressure is varied between normal pressure and 450 bar. Depending on the component size, thickness and polyurethane composition and thus the viscosity adjustment at the processing temperature, dynamic compression, ie changing pressurizations, can prove advantageous for the wetting of the fibers.

In one example, the temperature of the press is increased from 90 ° C during the Aufschmelzphase to 1 10 ° C, the pressure is increased after a melting phase of 3 minutes to 440 bar and then dynamically (7 times with each 1 minute duration) between 150 and 440 bar varies, the temperature is continuously increased to 140 ° C. Subsequently, the temperature is raised to 170 ° C and at the same time the pressure at 350 bar until removal of the composite component from the press after 30 minutes height, is held. The hard, stiff, chemical-resistant and impact-resistant composite components (plate goods) with one

Fiber volume fraction of> 50% are examined with regard to the degree of hardening (determination by DSC). The determination of the glass transition temperature of the cured matrix shows the progress of the crosslinking at different curing temperatures. In the case of the polyurethane composition used, the crosslinking is complete after about 25 minutes, in which case no reaction enthalpy for the crosslinking reaction is detectable any more. Two

Composites are manufactured under exactly the same conditions and then their properties are determined and compared.

Claims

claims

1. Prepregs, essentially composed of

A) at least one fiber-shaped carrier

and

B) at least one reactive or highly reactive polyurethane composition as matrix material,

Polyisocyanate as hardener a),

C) at least one film fixed on the prepreg by the polyurethane composition B).

Prepregs according to claim 1,

wherein the matrix material B) has a Tg of at least 40 ° C.

Prepregs according to at least one of the preceding claims,

characterized,

the prepregs have a fiber volume fraction of greater than 50%, preferably of greater than 50 to 70%, particularly preferably of 50 to 65%,

or

a fiber volume fraction of <50%, preferably <40%, particularly preferably <35%.

Prepregs according to at least one of the preceding claims,

characterized,

in that films or multilayer films based on thermoplastics or mixtures thereof or compounds, in particular of thermoplastic polyurethanes (TPU), thermoplastic polyolefins (TPO), (meth) acrylic polymers, polycarbonates, polyamides, polyetheresteramides, polyetheramides, polyvinylidene difluoride,

or metallized or metallic foils

are included.

5. prepregs according to at least one of the preceding claims,

characterized,

that films with a thickness between 0.2 and 10 mm, preferably between 0.5 and 4 mm are included.

6. prepregs according to at least one of the preceding claims,

characterized,

that polymers b) with hydroxyl groups, amino groups and thiol groups, in particular polyesters, polyethers, polyacrylates, polycarbonates and polyurethanes having an OH number of 20 to 500 mg KOH / gram and an average molecular weight of 250 to 6000 g / mol, are used.

7. direct melt impregnation method for producing prepregs according to at least one of the preceding claims,

characterized,

that di- or polyisocyanates selected from isophorone diisocyanate (IPDI),

Hexamethylene diisocyanate (HDI), diisocyanatodicyclohexylmethane (H12MDI), 2-methylpentane diisocyanate (MPDI), 2,2,4-trimethylhexamethylene diisocyanate / 2,4,4-trimethylhexamethylene diisocyanate (TMDI) and / or norbornane diisocyanate (NBDI), more preferably IPDI, HDI, TMDI and / or H ₁₂ MDI, where also the isocyanurates are used, can be used as starting compounds for the component a).

8. prepregs according to at least one of the preceding claims,

characterized,

external blocking agents selected from ethyl acetoacetate,

Diisopropylamine, methyl ethyl ketoxime, diethyl malonate, ε-caprolactam, 1, 2,4-triazole, phenol or substituted phenols and / or 3,5-dimethylpyrazole, be used to block a).

9. Prepregs according to at least one of the preceding claims,

characterized,

in that IPDI adducts, the isocyanurate groups and ε-caprolactam blocked isocyanate structures are used as component a).

0. Prepregs according to at least one of the preceding claims,

characterized,

the reactive polyurethane compositions B) contain additional catalysts, preferably dibutyltin dilaurate, zinc octoate, bismuth neodecanoate, and / or tertiary amines, preferably 1,4-diazabicyclo [2.2.2] octane, in amounts of 0.001-1% by weight.

1. Prepregs according to at least one of the preceding claims,

containing substantially at least one polyurethane matrix composition B) containing at least one reactive uretdione group-containing polyurethane composition

a) at least one hardening agent containing uretdione groups, based on

Polyadditionsverbindungen of aliphatic, (cyclo) aliphatic or

cycloaliphatic uretdione-containing polyisocyanates and

hydroxyl-containing compounds, wherein the hardener is present below 40 ° C. in solid form and above 125 ° C. in liquid form, has a free NCO content of less than 5% by weight and a uretdione content of 3 to 25% by weight, b) at least one hydroxyl-containing polymer which is in liquid form below 40 ° C in solid form and above 125 ° C and a

OH number between 20 and 200 mg KOH / gram,

c) optionally at least one catalyst,

d) optionally known from polyurethane chemistry auxiliary and

additives

so that the two components a) and b) are in the ratio that

to each hydroxyl group of component b) 0.3 to 1 uretdione group of

Component a) is omitted, preferably 0.45 to 0.55.

2. Prepregs, according to at least one of claims 1 to 9, with at least one

highly reactive powdery uretdione-containing polyurethane composition B) as matrix material, substantially containing

a) at least one hardener containing uretdione groups

and

b) optionally at least one polymer reactive with NCO groups

functional groups;

c) 0.1 to 5 wt .-% of at least one catalyst selected from quaternary

Ammonium salts and / or quaternary phosphonium salts with halogens, Hydroxides, alcoholates or organic or inorganic acid anions as counterion;

and

d) 0.1 to 5 wt .-% of at least one co-catalyst selected from

d1) at least one epoxide

and or

d2) at least one metal acetylacetonate and / or quaternary

Prepregs according to at least one of the preceding claims 1 to 9 or 12 containing at least one highly reactive powdery Uretdiongruppen

Polyurethane composition B) as matrix material, essentially containing

a) at least one hardening agent containing uretdione groups, based on

Polyadditionsverbindungen from aliphatic, (cyclo) aliphatic or cycloaliphatic uretdione groups containing polyisocyanates and

hydroxyl-containing compounds, wherein the hardener is below 40 ° C. in solid form and above 125 ° C. in liquid form and has a free NCO content of less than 5% by weight and a uretdione content of 3 to 25% by weight,

b) at least one hydroxyl-containing polymer which is in liquid form below 40 ° C in solid form and above 125 ° C and an OH number between 20 and 200 mg KOH / gram;

c) from 0.1 to 5% by weight of at least one catalyst selected from quaternary ammonium salts and / or quaternary phosphonium salts with halogens, hydroxides, alcoholates or organic or inorganic acid anions as counterion;

and

d) 0.1 to 5 wt .-% of at least one co-catalyst selected from

d1) at least one epoxide

and or

d2) at least one metal acetylacetonate and / or quaternary

Ammonium acetylacetonate and / or quaternary

Phosphoniumacetylacetonat; e) optionally known auxiliaries and additives from polyurethane chemistry, so that the two components a) and b) are present in the ratio that 0.3 to 1 uretdione group of component a) is required for each hydroxyl group of component b), preferably 0, 6 to 0.9.

Use of the prepregs according to at least one of the preceding claims 1 to 13, in particular with fiber-shaped carriers made of glass, carbon or aramid fibers.

Use of the prepregs according to at least one of claims 1 to 14,

for the production of composites in boat and shipbuilding, in the air and

Space technology, in the automotive industry, for motorcycles preferred motorcycles and

Bicycles, in the fields of automotive, construction, medical technology, sports,

Electrical and electronics industry, power generation equipment, such as

Rotor blades in wind turbines.

Composite components produced from prepregs according to at least one of claims 1 to 13.