WO2013098203A2

WO2013098203A2 - Textile-reinforced molded body, method for producing same, and use thereof

Info

Publication number: WO2013098203A2
Application number: PCT/EP2012/076460
Authority: WO
Inventors: Frank Hermanutz
Original assignee: Deutsche Institute Für Textil- Und Faserforschung Denkendorf
Priority date: 2011-12-29
Filing date: 2012-12-20
Publication date: 2013-07-04
Also published as: DE102011122560A1; WO2013098203A3; DE102011122560B4

Abstract

The invention relates to a molded body with an organic matrix which is reinforced with textile structures including fibers. Said molded body is produced by dissolving cellulose in a molten ionic liquid, the quantity of cellulose in the resulting cellulose-containing solution system advantageously being 2 to 30 wt.%, in particular 4 to 15 wt.%. The cellulose-containing solution system, which optionally comprises property-changing additives, is mixed with a textile structure, and the mixture is used to coagulate the cellulose into a coagulated medium. The resulting textile-reinforced molded body is washed and dried. Said molded body offers a wide variety of applications such as automobile interiors, for example as roof parts, side panels, or dashboards, for the automobile exterior area, in particular as underseal, as furniture parts, and for producing carbonized molded bodies which can be used for example as porous conductive matrices and separators or in fuel cells as cathodes and anodes or as membranes and separators.

Description

Textile reinforced molded body, a process for its preparation and its

use

description

The invention relates to a molded article or a composite material with an organic matrix, which is reinforced with textile structures, including fibers, a method for producing such a shaped article and its possible uses. The shaped body according to the invention is a composite material.

Composite materials are gaining in importance due to their outstanding specific properties, especially for lightweight applications. The use of organic materials, in particular of a thermoplastic nature, and of renewable raw materials leads to particular advantages with regard to recycling or availability, price and acceptance of the components of the composite materials. According to a known technical proposal, composite plates are produced in which a thermo-elastic cellulose acetate matrix is reinforced unidirectionally with viscose tire cord continuous fibers. This is done by a two-stage prepreg process wherein the reinforcing fibers are impregnated with the matrix. Thereafter, the resulting prepregs are compacted under heat and the fiber content adjusted to about 30 vol .-% (see M. Horvath, "fiber composites with thermoplastic matrix based on renewable raw materials", dissertation.de, published on the Internet, 2001, p / 14).

The products obtained by the above process show various advantages, such as a reduction in the thermal expansion of the addressed matrix, a advantageous adhesion between viscose tire cord fibers and the cellulose acetate matrix, which was investigated and confirmed inter alia by scanning electron micrographs of fractures. Advantageous mechanical parameters are set (modulus of elasticity, tensile strength, flexural modulus), which are significantly improved over those of the pure matrix. The thermal properties of the composite materials described are superior to those of the pure matrix. The average coefficient of thermal expansion between -10 and + 30 ° C is significantly smaller in the composite materials than in the matrix.

WO 96/36666 describes moldings of a composite material based on cellulose acetate and reinforcing cellulose-containing fibers which correspond to those described above. The core idea of these known shaped bodies is that the cellulose acetate has a degree of substitution (DS) of about 1.2 to 2.7 and the molding has a Vicat temperature of at least about 160 ° C and the mass ratio of cellulose acetate to natural cellulose fibers or cellulose fibers natural cellulosic fibers is about 10:90 to 90:10.

The fiber-reinforced composite materials of the type described above, which are based on thermoplastics, have in the meantime gained importance in various technical fields of application. In particular, this relates to natural fiber reinforced plastics (NFK). These composites are made of a plastic that maintains its stability by incorporating natural fibers. Components made of NFK not only have high rigidity and strength, but also a low density and are already economically competitive today. In 2003, the German automotive industry used approximately 45,000 tons of NFK primarily in the passenger compartment, such as interior linings, hat racks, boot linings, spare wheel wells and pillar trim right up to the dashboard. Meanwhile, first components z. B. produced as underbody protection on the basis of NFK in series. The natural fibers are particularly based on flax, hemp, jute, kenaf, sisal or abaca. The natural fiber reinforced composites based on thermoplastics have many advantages as mentioned above. In addition, they are up to 30% lighter than conventional fiber composites, do not splinter and break without sharp edges. In general, production costs are low, although a molded part is more expensive to produce than a part made of pure plastic. There are also ecological advantages associated with natural-fiber-reinforced composites: In recent years, a series of physical, energy and life-cycle assessments has been prepared in Germany. Compared with previous technical solutions, the NFK materials performed better in virtually all cases. A natural fiber molding can be produced with about half the energy of an ABS component. Other resin systems, for example based on renewable raw materials, can bring further savings. In addition, more energy can be saved during the life of a vehicle equipped with NFK. For example, because the panels are lighter than fiberglass (GRP) materials, the vehicle requires less fuel. Further advantages consist in a favorable disposal of the composite materials. The thermal utilization (combustion) of the natural fiber content is largely C0 ₂ -neutral. In the case of thermoplastic NFK, material recycling is possible in contrast to glass fiber reinforced plastics. From the material can z. B. a new polypropylene (PP) -NF granules are produced with relatively good properties. In one of the common disposal methods, such as the burning of shredded NFP parts, natural fibers, in contrast to glass fibers and mineral fillers, contribute positively to the material and energy balance (References: "Natural fiber reinforced plastics (NFP)", brochure nova-Institut GmbH, Hürth, March 2006).

The invention was based on the object, the above-described prior art, in particular that shown in the introduction, namely a molded body with an organic matrix, which is reinforced with textile structures, including fibers, so educate that its disadvantages, but the latter Advantages to be maintained. In particular, a varietal, compostable composite material or molded body of the type described should be able to be provided. In particular, the adhesion between the reinforcing textile structures and the matrix is to be improved.

According to the invention, this object is achieved by a shaped body having an organic matrix which is reinforced with textile structures, including fibers, in that the matrix is based on cellulose. In the selection of the cellulose for the molding according to the invention, the skilled person is not subject to any significant restrictions. The cellulose source can be of a variety of types. So it may be cellulose of natural origin, such as cotton, linters, hemp, flax, etc., but also to a chemical or paper pulp.

It is advantageous if the degree of polymerization (DP) of the respective cellulose is between 108 and 5500, in particular between 250 and 2000. If the value falls below 200, the matrix properties are adversely affected, while if the value of 5500 is exceeded, the production, which will be described in detail below, is made more difficult.

The term "textile structure" is to be understood in the context of the invention in general. These may be, for example, pure fibers or filaments, but also structures which are based on the pure fibers or filaments, wherein the fibers or filaments can be ordered or also disposed of in an unordered manner. Thus, for example, they can be arranged in one direction or randomly in the shaped body according to the invention. If they are included unidirectionally, then this leads to an amplification effect in the fiber direction. The textile structures are preferably in the form of endless fibers (filaments), short fibers or staple fibers, yarns and / or as textile fabrics. It is advantageous if the textile fabrics are in the form of woven, knitted, knitted, braided, laid, wound or nonwoven fabric.

In principle, both natural fibers and synthetic fibers are suitable for the fibers within the scope of the invention. The selection depends on certain aspects of the application in the composite material. The natural fibers lead to a single-formed molding. If special strength properties are to be sought, then it makes sense in individual cases to use chemical fibers in the form of high-performance fibers, such as aramids or else carbon fibers and the like.

A variety of different fibers are available to the person skilled in the art for the realization of the invention. It is expedient if the natural fibers of seed fibers, especially of cotton, bast fibers, in particular of flax, hemp, jute, kinap, ramie, abaca, rosenna and / or uran, hard fibers, in particular of alpha or Espatogras, Fique, Henequen, coconut, Manila, porphium and / or glisal, animal fibers, in particular of wool or fine and coarse animal hair, wood fibers, leaf fibers and / or silk represent.

Furthermore, it is associated with particular advantages if the mentioned man-made fibers, in particular based on modified natural materials of plant origin, and in particular represent: copper silk fibers, viscose fibers, modal fibers, rayon and cellulose acetate fibers, in particular as acetate or triacetate, alginate fibers, polyisoprene fibers or synthetic fibers, in particular elastofibres, fluorofibres, polyacrylic fibers, in particular based on polyacrylonitrile, or modacrylic, polyamide fibers, in particular nylon or aramid fibers, polychloride fibers, in particular based on polyvinyl chloride and polyvinylidene chloride, polyester fibers, polyolefin fibers, in particular based on polyethylene and polypropylene , or polyvinyl alcohol fibers.

In individual cases, it is particularly preferred if inorganic chemical fibers, in particular based on glass or ceramic, and carbon fibers or metal fibers are used for the purpose of the invention. These are special high-performance fibers in order to achieve particularly high strength values in the composite material.

In the context of the invention, it is also possible to use modified fibers, in particular modified natural fibers. Thus, with refined, fibrillated natural fibers z. B. produce very stable composites. In some cases, double characteristic values are achieved, which correspond to those of glass fiber reinforced parts. The fibrillation can be carried out mechanically, physically-chemically or else enzymatically.

It is expedient if the degree of fineness of the individual fibers selected according to the invention, irrespective of whether they are present as such in the yarn or in a textile structure or fabric, is 0, 1 dtex to 15 dtex, in particular 0.3 to 6 dtex.

The proportion of fibers, also here regardless of whether alone, ordered or disordered or integrated into a textile structure, is in the molding preferably between 10 and 90 wt .-%, in particular between 20 and 75 wt. %. Particularly ideal here is the weight percent range of 40 to 65 wt .-% to designate. The maximum value must indicate that exceeding may adversely affect the adhesion (interlaminar shear strength).

The molded body obtained according to the invention is distinguished by a variety of advantageous physical characteristics, which are very satisfactory compared with the products of the prior art used for comparison, but with the above-mentioned disadvantages, such as by a flexural strength (according to ASTM D 790-97) of 500 to 10,000 [MPa], in particular from about 1000 to 5000 [MPa], and / or a tensile strength (according to DIN ISO 527-1) of 175 to 20,000 [MPa], especially from about 1000 to 20,000 [MPa], especially preferably from 2500 to 10000 [MPa], and / or an interlaminar shear strength of from 25 to 2000 [MPa], in particular from 50 to 1000 [MPa] (measured according to ASTM D 2344-84, Short Beam Test) and / or an E Module (according to DIN ISO 527-1) of 1000 to 20000 [MPa], in particular from about 2500 to 10000 [MPa]. This list of advantageous physical characteristics of the molding according to the invention is not restrictive.

In many cases, it is of particular advantage if the matrix consists solely of cellulose. In order to achieve a desirable property change of the composite, as will be discussed below, the inclusion of additives may be advantageous. The property-modifying additives are in particular in the form of mineral materials, in particular calcium carbonate, calcium sulfate, silicon dioxide and / or aluminum silicate, microcapsules, pore formers, plasticizers, matting agents, flame retardants, bactericides, crosslinking agents, water repellents, antistatic agents and / or colorants, in particular pigments.

Particular advantages of the invention can also be obtained by incorporating polymer additives onto the shaped body based on an organic matrix according to the invention. These are polymers which, like the cellulose included according to the invention, can be dissolved in the ionic liquids in question. They should be compatible with the cellulose in this solution and should not interfere with downstream measures. This can be expertly determined easily and easily. As an example for Polymers could be mentioned polyethers, such as polyalkylene glycols or polyalkylene oxides, polyesters, such as polyethylene terephthalate or polybutylene terephthalate, cellulose esters, such as cellulose acetate, cellulose butyrate, cellulose propionate, triacetate or cellulose carbamate, cellulose alginate, polyamides, polyimides, polyacrylonitriles, polyaramides, polyurethanes , Polyacrylates such as polyacrylic acid, polyolefins, polyvinyl chloride, polyvinylidene chloride and polyvinyl alcohols. It is important that the cellulose remains the main component, it being possible as a rule to indicate that the proportion of polymer additives within the molding according to the invention is not more than 30%, in particular not more than 20%, the maximum content being 10% by weight, in particular of 5% by weight is advantageously maintained. In individual cases, the proportion of polymer additives to ensure the desired properties of the molding should be largely excluded, in particular be completely excluded. The above percentages by weight relate to the total amount of polymer components (cellulose plus polymer additives).

In the sense of the above-mentioned special other uses, especially in the automotive sector, the molding according to the invention is advantageously planar, and it is expedient in individual cases, to press together several sheet-like moldings according to the invention.

The technical success associated with the invention, as described above in the description of the shaped bodies according to the invention, lies in a special production process. This is characterized in that the cellulose is dissolved as pulp and / or as cellulose of natural origin in a molten ionic liquid, wherein in the resulting cellulose-containing solution system, the amount of cellulose expediently 2 to 30 wt .-%, in particular 4 to 15 wt .-%, the cellulose-containing solution system, optionally with incorporated property-improving additives, mixed with a textile structure and this mixing system for coagulating the cellulose contained in the solution system in a coagulant containing coagulation medium, in particular in an aqueous coagulation and introduced by Coagulation resulting moldings are washed and dried. In carrying out the method according to the invention, there is no relevant restriction on the type of ionic liquid. It is preferred if ionic liquids according to the general formula [Q +] _n [Z] ^{n "} are used, where the cation [Q +] _{n is} a quaternized ammonium [R 1 R 2 R 3 R 4 N +], phosphonium [R 1 R 2 R 3 R 4 P +] or sulfonium [ RlR2R3S +] cation or an analogous quaternized nitrogen, phosphorus or sulfur heteroaromatic of the following formulas I), (II), (III), (IV), (V) and (VI)

Pyrrolidinium Quinolinium

(V) (VI), where the radicals R 1, R 2, R 3, R 4 or the radicals R 1 to R 8 in the formulas (I) to (VI) independently of one another are linear, cyclic, branched, saturated or unsaturated alkyl radicals, mono- or polycyclic, aromatic or heteroaromatic radicals or derivatives of these radicals substituted by further functional groups, where R 1, R 2, R 3 and R 4 may be linked to one another, where the anion [Z] ^{n 'is} in the form of a halide, pseudohalide, amide, in the form of phosphorus bonds or nitro compounds.

An embodiment of these ionic liquids which are particularly advantageous in the context of the invention can be seen in the fact that the halides or pseudohalides de the formula F ^" , CI ^" , Br ^" , Γ, BF ₄ ^" , PF ₆ ^" , AICI ₄ ^" , AI ₂ CI ₇ ^" , AI3CI10 ^" , AIBr ₄ , FeCl ₄ ^" , BCI ₄ ^" , SbF ₆ ^" , AsF ₆ ^", ZnCl _^3", SnCl ₃ ^", CuCl _^2", CF3SO3 ^"(CN) ₂ ^N", (CF ₃ S0 ₃₎ ₂ N-, CF ₃ C0 ₂ ^", CCI ₃ C0 _^2", CN ^" , SCN ^" , OCN ^" , the phosphorus compounds phosphates of the formula P0 ₄ ^{3 "} , HP0 ₄ ^2" , H ₂ P0 ₄ ^" , ^ PO ^ ^" , HR ¹ P0 ₄ ^" , R ¹ R ² P0 ₄ ^" ; Phosphonates and phosphinates of the formula: R ^ PC, R ^ PC, R ^ PC; Phosphites of the formula: P0 ₃ ^{3 "} , HPO ₃ ^2" , H ₂ PO ₃ ^" , R 1 Os ^2" , R 1 PC, R ¹ R ² P0 ₃ ^" , and phosphonites and phosphinites of the formula: R ¹ R ² P 0 ₂ ^" , R ¹ HP0 ₂ ^" , R ¹ R ² PO ^" , R ^ PO ^" .

It is of further advantage if the alkyl radical in the form of a Ci-Ci ₈ - alkyl radical, in particular an alkyl radical having 1 to 4 carbon atoms, preferably ^¬ before a methyl, ethyl, 1-propyl, 2-propyl, 1- butyl, or 2-butyl group is present, the cyclic alkyl group is present ₀ i -cycloalkyl radical, and in particular in the form of a cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl radical in the form of a C _3, the alkyl radical unsaturated in the form of a vinyl, 2 Propenyl, 3-butenyl, cis-2-butenyl, trans-2-butenyl radical is present, the aromatic radical in the form of a phenyl or naphthyl radical is present, having 1 to 3 halogen atoms, alkyl radicals having 1 to 4 Carbon atoms or phenyl radicals, and the heteroaromatic radical is in the form of a 0-, S- or N-containing heterocyclic radical having 2 to 5 carbon atoms. It has proven to be particularly advantageous as ionic liquid [EMIM] [DCA], [EMIM] [CI], [EMIM] [SCN], [EMIM] [acetate], [EMIM] [DEP] and / or [MMIM ] [DMP]. The abbreviations have the following meaning: EMIM = ethylmethylimidazolium; [MMIM] = dimethylimidazolium; [DCA] = dicyanamide; [DMP] = dimethyl phosphate; [DEP] = diethyl phosphate.

In carrying out the process according to the invention, it has proven advantageous that the temperature of the molten ionic liquid is less than 160 ° C., in particular less than 130 ° C., and / or more than 20 ° C., in particular more than 30 ° C., is set. Expediently, these parameters for the temperature are maintained in the course of the process until the solution system is introduced into a coagulation medium. As a preferred framework for the range of the melting point of each ionic liquid used, a range of -100 ° C to + 150 ° C, in particular from -30 ° C to + 80 ° C, could be specified. It is advantageous if an initial cellulose having an average degree of polymerization of from 108 to 5500, in particular from 250 to 2000, is used to form the matrix of the body according to the invention. Surprisingly, it has been shown that in carrying out the preparation process according to the invention, the cellulose incorporated is not degraded substantially, but the starting cellulose and the matrix-forming cellulose of the inventive molding have a substantially same degree of polymerization, especially if the preparation of the solution of cellulose in the ionic liquid is carried out under a protective gas atmosphere, for example under a nitrogen atmosphere. In an oxidizing atmosphere, it is possible to set the degree of polymerization of the cellulose and thus the viscosity of the solution system targeted. It is advantageous to maintain these frameworks in the incorporation of the textile materials as presented above. Attention should be paid to the maximum temperature of the ionic liquid used, including that of the solution system, if it is desired to avoid degradation of the cellulose during the course of the process. There are cases where the degradation of the cellulose is desired to some extent. Then a regulated degradation can be controlled by a specially set maximum temperature.

The mixing of the starting constituents of the solution system, in particular of the ionic liquid and of the cellulose contained therein, preferably takes place under the action of high shear forces, in particular by means of an extruder. In this case, a twin-screw extruder has proven to be particularly advantageous. The dissolution is further favored by simultaneously irradiated with microwaves during mixing, in particular ultrasound comes to act.

In order to optimize the method according to the invention, various options are available to the person skilled in the art. Thus, it is preferred that the addressed solution system is set to a zero viscosity (measured with a rotational viscometer) between 2 and 1000 Pa.s, in particular between 10 and 250 Pa.s, wherein from these frames of the zero viscosity the processing of the solution system for example, in an extruder is particularly advantageous. As a preferred framework for the content of cellulose in the ionic liquid is a range of 2 to 30, in particular 4 to 15 wt -.% To indicate. If the value falls below 2% by weight, the solutions are too low in viscosity, while exceeding the value of 30% by weight leads to difficulties in processing because of the high solution viscosity.

To set an optimal solution system containing cellulose, it is done so that the cellulose-containing solution system before mixing with the textile structures at 10 to 140 ° C, in particular at 40 to 120 ° C, and / or the coagulation medium to a Temperature of about 20 to 90 ° C, in particular 20 to 60 ° C is set.

In order to set the advantages sought by the invention with particular certainty, it is preferred that the cellulose-containing solution system is filtered, this taking place in particular under pressurization and the filtered solution system is fed to the coagulation medium. A particularly advantageous development is then that the filtered solution system is subsequently degassed and before it is introduced into the coagulation medium, which also takes place in particular under the action of a vacuum.

In choosing the coagulating agent for the coagulating medium, the invention is not subject to any relevant restrictions. Thus, it is preferred if the coagulation medium as coagulant water, monoalcohols, especially methanol, ethanol, propanol and / or butanol, polyhydric alcohols, especially glycerol, ethylene glycol, diethylene glycol, triethylene glycol, 1,4-butanediol, 1,2-propanediol, 1,3-propanediol and / or 1,6-hexanediol, or mixtures of these coagulants. For a preferred quantitative composition of the coagulating medium, it can be stated that the coagulating agent is used in the coagulating medium in an amount of from 5 to 95% by weight, in particular from 20 to 80% by weight.

With regard to the process control and property control of the process product, it is advantageous if the coagulation medium contains the ionic liquid present in the solution system or another ionic liquid suitable according to the invention in an amount of from 5 to 70% by weight, in particular from 10 to 30 wt .-% contains. This allows coagulation to be delayed and a compact, well-consolidated product to be obtained.

As already stated above, additives can be included in the shaped body according to the invention. The above-described additives are therefore used in the process. As a result, they can already be added to the pure ionic liquid, to the cellulose-containing solution system and / or to the mixture containing the cellulose-containing solution system and the textile structures.

After formation of the shaped body in the coagulation medium, this is removed therefrom. It then preferably follows a washing with water and / or a monoalcohol, in particular with methanol, ethanol, propanol and / or butanol, expediently between 20 and 80 ° C. The washing or rinsing is preferably carried out with demineralized water. Here, the washing water can be pressed between two rollers. Drying in a temperature range of preferably 60 to 160 ° C, especially 80 ° C to 130 ° C, follows in a non-limiting manner. For example, the composite body can be pressed in a heating press in this temperature frame and dried under elevated pressure, for example, from 2 N / cm ² to 16 N / cm ² .

The drying can be configured in many ways. For example, drying for composite consolidation in an oven can be done at 80 to 160 ° C. In a particular embodiment, for example, composite panels are preferably pressed between rolls and dried in a hot press. After drying, a further shaping can take place in a press. The washed and dried shaped bodies obtained in the above manner can be subjected to aftertreatments, so in particular a further shaping in a heating press and / or a mechanical action, in particular a cutting, or a surface treatment or a chemical action, in particular a gluing done ,

As can readily be seen, the molding according to the invention is open due to the described properties of a large number of advantageous uses. Of particular importance is its use as a car interior part, in particular as a roof part, Seitenverkleidu ng, door trim, Trunk lining, spare wheel well, pillar trim and dashboard, for the automotive exterior as underbody protection, as a promenade, as a noise barrier, as a railing, as windows and doors, as a window and door profile, as a window frame, as a fence system, as packaging material, as insulating material or furniture part :

In the above and other advantageous applications, the following properties of the shaped bodies according to the invention play a relevant role: In the case of cellulosic fibers, the shaped bodies are sorted and compostable. They show a special adhesion between the cellulosic matrix and the embedded cellulosic fibers. These properties exceed those of the known fiber reinforced composites based on thermoplastics. In addition, the molded articles according to the invention have the advantageous properties of the fiber-reinforced composites of the prior art. They are characterized by good characteristics of flexural strength, tensile strength of the modulus of elasticity and interlaminar shear strength, which means good adhesion. The particularly strong adhesion results from the fact that in carrying out the method according to the invention, a dissolution of the fibers takes place. This solubilization applies not only to cellulosic fibers, but also to those chemically different types of fibers that can be dissolved or dissolved to some extent in the ionic liquid. The triggering process can be specifically controlled over time and temperature. A particularly advantageous development of the shaped bodies according to the invention consists in that the ionic liquid can be separated from the precipitation medium and recycled again into the overall process. Incidentally, the same applies to the cellulose matrix of the molding according to the invention, if it is consumed in its application and would have to be disposed of.

The advantage of the shaped bodies according to the invention is also that they are accessible to further processing by carbonization. The carbonization can be carried out by conventional methods, in particular in an inert gas atmosphere. Here, as the preferred temperature range 400 ° C to 3000 ° C, in particular 700 ° C to 2400 ° C, are given. In individual cases, it may be appropriate to design the carbonation in such a way that it involves a graphitis treatment. Also, graphitization may be followed by carbonation. These are expert actions. By carbonizing special porous structures are achieved, which can be used advantageously in batteries as a porous conductive matrix and separators or in fuel cells as a cathode, anode or as membranes and separators advantageous. Due to the production-related, very homogeneous smooth surface of the carbonized shaped body conductive structures are maintained, which equals a metallic conductivity. This could be a justification for the advantageous applications. The properties of the carbonized shaped article can be regulated or controlled in particular by correspondingly corresponding properties being imparted to the inventive (non-carbonized) shaped article according to the method, which then have an effect on the properties of the carbonized shaped article. Thus, for example, a selective permeability for ions, such as lithium ions, can be achieved.

Other advantages that can be achieved with the invention include recycling by complete recycling of the unmixed cellulose composite material by redissolution in the ionic liquid, a favorable production by decoupling from the price of crude oil, the adjustment of new surface properties, such as a desirable paintability and training more appropriate chemical functionalities, as well as the use of pure cellulose.

The invention will be explained in more detail below with reference to examples:

Example 1 :

The invention relates to the production of a shaped article based on cellulose according to the invention which contains a cotton twill fabric for reinforcement. Here, 100 g of cotton linters are dissolved in 900 g of ethyl methylimidazolium acetate (EMIM acetate) by stirring for 60 min at 80 ° C. The cellulose solution obtained is filtered through a metal sieve (20 μm mesh size). A cotton twill fabric is impregnated on both sides with this solution using a padder. The order is 20 wt .-%, based on the finished shaped body. Four layers of impregnated fabric are laid one on top of the other. The resulting impregnated fabric package is maintained at 80 ° C for 2 minutes. The solvent in The form of the designated ionic liquid is washed out of demineralized water in a coagulation bath. Thereafter, the washing water is pressed between two rollers. The four-layer composite body according to the invention is dried in a hot press at a temperature of 120 ° C. and under a pressure of 8 N / cm ² . The following properties are set in the composite body: E-modulus 5400 [M Pa], tensile strength 350 [M Pa] and flexural strength 1200 [M Pa].

Example 2:

Described is the preparation of a shaped body according to the invention based on cellulose, which contains m-aramid fibers for reinforcement. In this case, 50 g of eu lyptu szel lstoff (DP650) in 600 g of ethyl-methyl imidazole iu md iethyl phosphate (EMIM-DEP) by stirring for 60 min at 85 ° C dissolved. The cellulose solution obtained is filtered through a metal sieve (20 μm mesh size). An m-aramid fabric is impregnated on both sides with this solution using a doctor blade. The order is 15% by weight, based on the finished molding. Two layers of the impregnated fabric are placed over each other and stored for 20 min in a convection oven at 100 ° C. The solvent in the form of the designated ionic liquid is washed out of demineralized water in a coagulation bath. Thereafter, the washing water is pressed between two rollers. The resulting two-layer composite body is dried in a hot press at a temperature of 120 ° C and under a pressure of 8 N / cm ² . The following properties occur in the composite body: modulus of elasticity 8400 [M Pa], tensile strength 425 [M Pa] and flexural strength 2400 [M Pa].

Example 3:

The invention relates to the production of a shaped article based on cellulose according to the invention, which contains polyamide fibers for reinforcement. In this case, 50 g of eucalyptus pulp (DP650) are dissolved in 600 g of ethyl methylimidazolium diethyl phosphate (EMIM-DEP) by stirring for 60 min at 85 ° C. The cellulose solution obtained is filtered through a metal sieve (20 μm mesh size). A polyamide fabric is impregnated on both sides with this solution by means of a doctor blade. The order is 15 wt .-%, based on the finished shaped body. Two layers of the impregnated fabric are placed over each other and stored for 20 min in a convection oven at 100 ° C. The solvent in the form of the designated ionic liquid is dissolved in a demineralizing coagulation bath. Washed out with water. Thereafter, the washing water is pressed between two rollers. The resulting two-layer composite body is dried in a hot press at a temperature of 120 ° C and under a pressure of 8 N / cm ² . In this case, the following properties occur in the composite body: modulus of elasticity 56000 [M Pa], tensile strength 195 [M Pa] and flexural strength 1250 [MPa].

Example 4:

The invention relates to the production of a shaped article based on cellulose according to the invention which contains viscose tire cord fibers for reinforcement. In this case, 100 g of cotton linters are dissolved in 900 g of ethyl methylimidazolium acetate (EMIM acetate) by stirring for 60 min at 80 ° C. The cellulose solution obtained is filtered through a metal sieve (20 μm mesh size). Viscose tire cord fibers are wound in parallel on a metal frame. With the help of a doctor blade is impregnated on both sides with this solution. The order is 30 wt .-%, based on the finished molded body. The resulting impregnated fiber fabric is kept at 80 ° C for 2 minutes. The solvent in the form of the designated ionic liquid is washed out of demineralized water in a coagulation bath. Thereafter, the washing water is pressed between two rollers. The resulting fiber composite body is dried in a hot press at a temperature of 120 ° C and under a pressure of 8 N / cm ² . The following properties are set in the composite body: modulus of elasticity 3875 [M Pa], tensile strength 750 [M Pa] and flexural strength 1500 [M Pa].

Example 5 Recycling of the Composite Materials According to Example 1

50 g of the composite material are comminuted in a 2 mm mesh cutter mill and the sieve fraction is dissolved in 450 g of ethyl methylimidazolium acetate (EMIM acetate) by stirring for 60 min at 80 ° C. The cellulose solution obtained is filtered through a metal sieve (20 μm mesh size) and reused for impregnating reinforcing fibers.

# # #

Claims

claims

An organic matrix shaped body reinforced with textile structures, including fibers, characterized in that the matrix is based on cellulose.

2. Shaped body according to claim 1, characterized in that the cellulose is of natural origin or represents a pulp in the form of a chemical pulp or paper pulp.

3. Cellulose according to claim 1 or 2, characterized in that the degree of polymerisation (DP) of the cellulose is between about 108 and 5500, in particular between about 250 and 2000.

4. Shaped body according to one of claims 1 to 3, characterized in that the textile structures in the form of continuous fibers, short or staple fibers, yarns and / or textile fabrics are present.

5. Shaped body according to claim 4, characterized in that the textile fabrics are present as fabric, knitted fabric, knitted fabric, braid, scrim, winding or nonwoven fabric.

6. Shaped body according to one of claims 1 to 5, characterized in that the fibers of the fabric Natu rfasern and / or man-made fibers.

7. Shaped body according to claim 6, characterized in that the natural fibers are seed fibers, in particular of cotton, bast fibers, in particular of flax, hemp, jute, kinap, ramie, abaca, rosenna and / or uran, hard fibers, in particular of alpha or Espatogras, Fique, Henequen, coconut, manila, porphium and / or glisal, animal fibers, in particular of wool or fine and coarse animal hair, wood fibers, leaf fibers and / or silk represent.

8. Shaped body according to at least one of claims 2 to 7, characterized in that the man-made fibers, in particular based on modified natural Substances of vegetable origin, in particular copper silk fibers, viscose fibers, modal fibers, rayon and cellulose acetate fibers, in particular as acetate or triacetate, alginate fibers, polyisoprene fibers or synthetic fibers, in particular elastofibres, fluorofibers, polyacrylic fibers, in particular based on polyacrylonitrile or modacrylic, polyamide fibers, in particular nylon or aramid fibers, polychloride fibers, in particular based on polyvinyl chloride and polyvinylidene chloride, polyester fibers, polyolefin fibers, in particular based on polyethylene and polypropylene, or polyvinyl alcohol fibers.

9. Shaped body according to claim 8, characterized in that it contains inorganic chemical fibers, in particular based on glass or ceramic, carbon fibers or metal fibers.

10. Shaped body according to at least one of the preceding claims, characterized in that the degree of fineness of the individual fibers is 0, 1 dtex to 15 dtex, in particular 0.3 to 6 dtex.

11. Shaped body according to at least one of the preceding claims, characterized in that the proportion of fibers in the shaped body between 10 and 90 wt -.%, In particular between 20 and 75 wt .-%, is located.

12. Shaped body according to at least one of the preceding claims, characterized in that its flexural strength (according to ASTM D 790-97) 500 to 10,000 [M Pa], in particular 1000 to 5000 [MPa], its tensile strength (according to DIN ISO 527-1) from 175 to 20,000 [MPa], in particular from about 1,000 to 10,000 [M Pa] and / or its modulus of elasticity (according to DIN ISO 527-1) from 1,000 to 20,000 [MPa], in particular from 2,500 to 10,000 [MPa].

13. Shaped body according to at least one of the preceding claims, characterized in that the interlaminar shear strength is 25 to 2000 [MPa], in particular 50 to 1000 [MPa] (measured according to ASTM D 2344-84, short beam test).

14. Shaped body according to at least one of the preceding claims, characterized in that its matrix consists of cellulose.

15. Shaped body according to at least one of the preceding claims, characterized in that it property-modifying additives, in particular in the form of mineral materials, in particular calcium carbonate, calcium sulfate, silica and / or aluminum silicate, microcapsules, pore formers, plasticizers, matting agents, flame retardants, bactericides, crosslinking agents, Hydrophobizing agents, antistatic agents and / or colorants, in particular pigments containing.

16. Shaped body according to at least one of the preceding claims, characterized in that it is planar.

17. Shaped body according to claim 16, characterized in that a plurality of surface-shaped shaped bodies are pressed together.

18. A process for producing a shaped article according to at least one of the preceding claims, characterized in that the cellulose is dissolved as pulp and / or cellulose Cel of natural origin in a molten ionic liquid, wherein in the resulting cellulose-containing solution system, the amount of cellulose expediently about 2 to 30% by weight, in particular 4 to 15 wt .-%, the cellulose-containing solution system, optionally with incorporated property-modifying additives, mixed with a textile structure and this mixing system for coagulating the cellulose contained in the solution in a Coagulation medium containing coagulant, in particular in an aqueous coagulation medium, introduced and the resulting coagulation molded body is washed and dried.

19. The method according to claim 18, characterized in that the temperature of the molten ionic liquid to less than 160 ° C, in particular less than 130 ° C, and / or more than about 20 ° C, in particular more than about 30 ° C, is set.

20. The method according to claim 18 or 19, characterized in that the cellulose has an average degree of polymerization of 108 to 5500, in particular from 250 to 2000 has.

21. The method according to at least one of claims 18 to 20, characterized in that the solution system has a zero viscosity (measured by a rotary visas viscometer) between 2 and 1000 Pa.s, in particular between 10 and 250 Pa.s.

22. The method according to at least one of claims 18 to 21, characterized in that the cellulose-containing solution system is filtered, in particular under pressurization or vacuum, and the filtered solution system is fed to the coagulation medium.

23. The method according to at least one of claims 18 to 22, characterized in that the cellulose-containing solution system after filtration and prior to introduction into the coagulation medium, in particular under the action of vacuum, is degassed.

24. The method according to at least one of claims 18 to 23, characterized in that the coagulation medium as coagulant water, Monoalko- hole, especially methanol, ethanol, propanol and / or butanol, polyhydric alcohols, especially glycerol, ethylene glycol, diethylene glycol, triethylene glycol, 1 , 4-butanediol, 1,2-propanediol, 1,3-propanediol and / or 1,6-hexanediol, or mixtures of these coagulants.

25. The method according to at least one of claims 18 to 24, characterized in that the coagulation medium contains the coagulant in an amount of 5 to 95 wt .-%, in particular from 20 to 80 wt -%.

26. The method according to at least one of the preceding claims 18 to 25, characterized in that in the coagulation medium, an ionic liquid or a mixture of ionic liquids in an amount of 5 to 70 wt .-%, in particular from 10 to 30 wt .-% , is used.

27. The method according to at least one of claims 18 to 26, characterized in that the cellulose-containing solution system before mixing with the textile structures at 10 to 140 ° C, in particular at 40 to 120 ° C, and / or the coagulation medium to a temperature from 20 to 90 ° C, in particular 20 to 60 ° C is set.

28. The method according to at least one of claims 18 to 27, characterized in that the washing with water and / or a monoalcohol, in particular methanol, ethanol, propanol and / or butanol, in particular in a temperature range of 20 to 80 ° C, is performed ,

29. The method according to at least one of claims 18 to 27, characterized in that after formation of the dried molded body, a further shaping in a hot press and / or by mechanical action, in particular cutting, or a surface treatment or a chemical action, in particular gluing , be performed.

30. The method according to at least one of the preceding claims 18 to 30, characterized in that ionic liquids according to the general formula [Q +] _n [Z] ^{n "} are used, wherein the cation [Q +] _n a quaternized ammonium [RlR2R3R4N + ], Phosphonium [R 1 R 2 R 3 R 4 P +] or sulfonium [R 1 R 2 R 3 S +] cation or an analogous quaternized nitrogen, phosphorus or sulfur heteroaromatic compound of the following formulas (I), (II), (III), (IV), (V) and (VI)

Imidazolium oxazolium tllazolium piperidinium I) (Π) (III) (IV)

Pyrrolidinium Quinolinium

(V) (VI) represents, wherein the radicals Rl, R2, R3, R4 or the radicals Rl to R8 in the formulas (I) to (VI) are independently linear, cyclic, branched, saturated or unsaturated alkyl radicals, mono- or polycyclic, aromatic or heteroaromatic radicals or derivatives of these radicals substituted with further functional groups, where R 1, R 2, R 3 and R 4 may be linked to one another, where the anion [Z] ^{n 'is} in the form of a halide, pseudohalide, amide, in the form of phosphorus bonds or nitro compounds is present.

31. The method according to claim 30, characterized in that the halides or pseudohalides the formula F ^" , CI ^" , Br ^" , Γ, BF ₄ ^" , PF ₆ ^" , AICI ₄ ^" , AI ₂ CI ₇ ^" , AI ₃ CI ₁₀ ^", AlBr _4, FeCl _^4", BCI ₄ ^", SbF _^6", AsF ₆ ^", ZnCl _^3", SnCl ₃ ^", CuCl _^2", CF ₃ S0 ₃ ^", (CN) ₂ ^N", (CF ₃ S0 ₃ ) ₂ N, CF ₃ C0 ₂ ^" , CCI ₃ C0 ₂ ^" , CN ^~ , SCN ^" , OCN ^" , the phosphorus compounds phosphates of the formula P0 ₄ ^{3 "} , H P0 ₄ ^2" , H ₂ P0 ₄ ^" , R ¹ P0 ₄ ^{2 "} , HR ¹ P0 ₄ ^" , R ¹ R ² P0 ₄ ^" , phosphonates and phosphinates of the formula: R 1 PC, R ¹ R ² P0 ₂ ^" , R ¹ R ² P0 ₃ ^" , phosphites of the formula P0 ₃ ^{3 "} , HP0 ₃ ^2" , H ₂ P0 ₃ ^" , R ¹ P0 ₃ ^2" , R ¹ HP0 ₃ ^" , R ¹ R ² P0 ₃ ^" ; and phosphonites and phosphinites of the formula: R ¹ R ² P0 ₂ ^" , R ^ PC, R ¹ R ² PO ^" , R ^ PO ^" represent.

32. The method according to any one of claims 30 or 31, characterized in that the alkyl radical in the form of a Ci-Ci ₈ alkyl, in particular an alkyl radical having 1 to 4 carbon atoms, preferably a methyl, ethyl, 1-propyl, 2 - Propyl, 1-butyl, or 2-butyl radical is present, the cyclic alkyl radical in the form of a C _3- io-cycloalkyl, in particular in the form of a cyclopropyl, cyclobutyl, cyclopentyl or cyclohexyl radical is present, the unsaturated Alkyl radical in the form of a vinyl, 2-propenyl, 3-butenyl, cis-2-butenyl, trans-2-butenyl radical is present, the aromatic radical is present in the form of a phenyl or naphthyl radical containing 1 to 3 halogen atoms, Alkyl radicals having 1 to 4 carbon atoms or phenyl radicals may be substituted, and the heteroaromatic radical is in the form of an O, S or N-containing heterocyclic radical having 2 to 5 carbon atoms.

33. The method according to at least one of claims 18 to 32, characterized in that as ionic liquid [EMIM] [DCA], [EMIM] [Cl], [EMIM] [SCN], [EMIM] [acetate], [EMIM] [DEP] and / or [MMIM] [DMP].

34. Use of a shaped article according to at least one of claims 1 to 17 as an automotive interior part, in particular as a roof part, side cover, door trim, boot lining, spare wheel well, pillar trim, as a dashboard, for the automotive exterior as underbody protection, as a promenade, as a noise barrier, as a railing , as windows and doors, also as a window and door profile, as a window frame, as a fence system, as packaging material, as insulating material or furniture part.

35. Use of a shaped article according to at least one of claims 1 to 17 for the preparation of a carbonized molded article, in particular by carbonization between 400 ° C and 3000 ° C, in particular between 700 ° C and 2400 ° C.

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