DE102013219960A1 - Co-extrusion, pultrusion of profiles with carbon waste - Google Patents

Abstract

The invention relates to a Kunststoffgranulatmischung containing carbon fiber reinforced plastic waste material, and a molding composition comprising a proportion of recycled carbon fiber reinforced plastic material, and a method for producing polymeric materials, in particular materials for use in motor vehicles, in which a component of thermosetting reticulated recycled fibers of a carbon fiber reinforced plastic waste material (carbon fibers) is used.

Description

The invention relates to a plastic granulate mixture according to claim 1, as well as a molding composition according to claim 5 and a process for the preparation of polymeric materials according to claim 6.

More particularly, the invention relates to a plastic granulate mixture containing carbon fiber-reinforced plastic waste material, and a molding composition comprising a proportion of recycled carbon fiber-reinforced plastic material, and a process for the production of polymeric materials, in particular materials for use in motor vehicles, in which a component of thermosettingly crosslinked recycled fibers a carbon fiber reinforced plastic waste material is used.

It is known in the prior art to supply plastics to a recyclate process in order to reuse them in a later further processing process. So z. B. in the DE 19710098 A1 discloses a process for producing polyethylene terephthalate (PET) recycled pulp from flakes, and a PET product produced by the process. PET products are used in a variety of applications, for example as bottles, qualified films and fibers, medical devices, in particular medical syringes and medical containers. It is endeavored to lead the products as fully as possible in the recycling cycle. A major problem, however, is that as the proportion of PET recyclate increases, the quality of the products is changed.

Molded parts made of polymeric materials, which are used in particular in the interior of motor vehicles, must meet high mechanical and environmental requirements and above all respect. Their mechanical properties, their surface properties, their aging and their odor and emission behavior meet the requirements. It is known that various polymeric materials are used for the production of components and moldings for the motor vehicle interior. A typical material used is a glass fiber reinforced ABS / PC material (polymer blend of acrylic-butadiene / styrene copolymer and polycarbonate). However, this material has inadequate UV resistance, poor flowability, poor heat aging behavior (toughness and elongation at break after heat storage) and unfavorable surface properties, as well as poor foam adhesion and, in particular, poor odor behavior. Odor behavior in plastics is understood to mean the tendency, after climate storage and in particular temperature exposure of a fixed duration and temperature, to tend to release volatile components which a human being can perceive.

As a further material is known in the art to use a tough [?] Modified and glass fiber reinforced SMA (styrene-maleic anhydride copolymer). Also, this plastic has only insufficient surface properties and shows a low heat resistance and insufficient heat aging resistance.

Another material which can be used for the production of molded parts in vehicles is PPE / HIPSGF (a polymer blend of polyphenylene ether and Hi-impact polystyrene and glass fibers). However, this material also has inadequate flowability, low UV resistance, poor heat aging, and also tends to release volatiles that manifest themselves as unsatisfactory odor behaviors.

In the prior art it is further known for mechanically stable components and moldings to use fiber-reinforced molded plastics. As reinforcing fibers, for example, glass fibers, natural fibers or carbon fibers or fillers are used in the production of structural parts. However, fiber materials such as glass fibers are expensive. Another disadvantage of glass fibers is that they are relatively heavy.

In the production of vehicle parts and vehicle interior parts, in particular in the production of profiles, extrusion, coextrusion and Pulstrusionsverfahren are used in the prior art. However, the high cost is still a limiting factor. The production of carbon fiber reinforced profiles or materials by these methods is therefore significantly affected by the cost of materials and the amount of fibers used.

It is therefore desirable to provide a manufacturing method for polymer molded parts in which the manufacturing costs are reduced and a positive environmental factor is achieved, that is, the environmental impact is reduced and resources are conserved.

It is therefore an object of the present invention to overcome said disadvantages and in particular to provide a Kunststoffgranulatmischung, a molding material and a method which allow a cost-effective production of moldings made of polymeric materials, which also show good processing properties and beyond a positive effect on the Have environment.

The basic idea of the invention is that of the mechanical properties of the polymeric materials to obtain suitable carbon fibers (carbon fibers) from a recycled material, which is admixed with a plastic polymer to use this by an extrusion, coextrusion or Pulstrusions method or the like, to moldings such as profiles or vehicle interior parts manufacture.

A first aspect of the invention is to mechanically comminute carbon fiber reinforced plastic or carbon fiber reinforced plastics materials to produce recycled fibers, preferably thermoset crosslinked and free flowing recycled fibers, to admix them to a plastic granule mixture in a desired mixing ratio to thereby provide the desired mechanical and technical properties of the plastic polymer or the molding to achieve.

Another aspect of the present invention is to provide a process, particularly an extrusion, coextrusion and pultrusion process, for producing profiles and moldings from carbon wastes, i. H. from fibers obtained by mechanical comminution of a carbon fiber reinforced plastic waste material.

Another aspect of the present invention is to provide molding compositions suitable for processing in an extrusion, coextrusion or pultrusion process which contains as a component at least one recycled carbon fiber waste scrap.

• – die Komponente A ein Kunststoffgranulat eines Kunststoffpolymers in der Menge von bis zu (100 – x – y) Gew.-% ist;
• – die Komponente B aus x Gew.-% duroplastisch vernetzten Rezyklat-Fasern besteht, die durch Zerkleinerung, vorzugweise mechanische Zerkleinerung aus einem kohlefaserverstärkten Kunststoffmaterial gewonnen wurden; und
• – die Komponente C aus 0 bis y Gew.-% an funktionsbildenden Additiven wie UV-Stabilisatoren, Pigmente, Oxidationsverzögerern, Gleit- und Entformungsmitteln besteht.

In a preferred embodiment of the invention, therefore, a Kunststoffgranulatmischung is proposed which contains the components A to C, wherein based on the sum of the components A to C, these total 100 wt .-% result, wherein

• Component A is a plastic granulate of a plastic polymer in the amount of up to (100-xy)% by weight;
• - The component B consists of x wt .-% thermosetting reticulated recycled fibers obtained by comminution, preferably mechanical comminution of a carbon fiber reinforced plastic material; and
• Component C consists of 0 to 5% by weight of function-forming additives such as UV stabilizers, pigments, antioxidants, lubricants and mold release agents.

Preferably, a carbon fiber (carbon fiber) is used for this, which was impregnated with a thermosetting resin systems and cured, comminuted and fed to the plastic granule mixture for use in a plastics processing process.

By using waste materials from carbon fiber reinforced plastic materials, in particular from such plastic waste with a high carbon fiber content, a plastic granulate mixture can be provided which can be used in extrusion, coextrusion and pultrusion processing processes and which in particular can be produced inexpensively and has a positive effect in the environmental balance shows that, on the one hand, waste materials were utilized and, in addition, new raw materials, in particular carbon fibers, can be saved.

In a particularly preferred embodiment of the invention, therefore, a plastic granulate mixture is provided, in which the recycled fibers represent carbon fibers, which by means of a recycling process, for. B. were obtained by crushing of a carbon fiber reinforced plastic waste material.

In a further preferred embodiment, the plastic granulate mixture has a weight fraction x of carbon fibers between 10% and 30%.

In any case, the aforementioned plastic granulate mixture always has a wt .-% content of thermosettingly crosslinked recycled fibers, while the proportion y of the component C to function-forming further additives may also be 0 wt .-%. Depending on the amount of component B, the mechanical stability and desired mechanical functionality of the future end product can be influenced.

It is preferred to provide a plastic granulate mixture in which the component A consists of a thermosetting polymer.

Another aspect of the present invention is to provide molding compositions for processing in an extrusion, coextrusion or pultrusion process. According to the invention, therefore, it is proposed to provide a molding composition which has the abovementioned components A, B and C in a desired mixing ratio, it also being possible for component C to be completely eliminated if no further function-forming additives are to be used.

• a) Zuführen einer Komponente A aus Kunststoffgranulat eines Kunststoffpolymers in der Menge von bis zu (100 – x) Gew.-%,
• b) Zudosieren zur Komponente A eine Komponente B aus x Gew.-% duroplastisch vernetzten Rezyklat-Fasern, die durch mechanische Zerkleinerung aus einem kohlefaserverstärktem Kunststoffabfallmaterial gewonnen wurden; und
• c) Herstellen eines Werkstoffs aus dem Komponentengemisch A und B mittels eines Kunststoffverarbeitungsprozesses, insbesondere mittels eines Extrusions-, Coextrusions- oder Pultrusionsverfahrens.

Another aspect of the present invention is to provide a process for producing polymeric materials, in particular for use in motor vehicles, comprising at least the following steps:

• a) feeding a component A of plastic granules of a plastic polymer in the amount of up to (100 - x) wt .-%,
• b) adding to component A a component B of x wt .-% thermosetting reticulated recycled fibers, which were obtained by mechanical comminution of a carbon fiber reinforced plastic waste material; and
• c) producing a material from the component mixture A and B by means of a plastic processing process, in particular by means of an extrusion, coextrusion or pultrusion process.

In a preferred embodiment of the process, component A is used in the amount (100-xy)% by weight and component C in the amount of 0 to 5% by weight, which is added to components A and B. is, wherein the sum of the components A, B and C results in a total of 100 wt .-%.

In this way, the mechanical, optical and other technical properties of the polymer materials to be produced by the process can be adjusted according to the requirements.

It is further preferred to use the component B as a thermosetting crosslinked carbon fiber, which is free-flowing, so that a metered addition by gravimetric metering can be done in a screw conveyor. In addition, thermosettingly crosslinked carbon fibers have surface properties which have a positive effect on the crosslinking properties of the materials with regard to crosslinking in the extrusion, coextrusion or pultrusion process.

In a further preferred embodiment of the process, component-forming additives such as UV stabilizers, pigments, antioxidants, lubricants and mold release agents are used as component C to form the material with the required additional properties such as color, deformability, UV resistance or other material properties ,

It is particularly preferred to use a thermosetting plastic granulate or a thermosetting molding composition in the extrusion, coextrusion or pultrusion process, since these have particularly good crosslinking properties with thermoset crosslinked carbon fibers. Other advantageous developments of the invention are characterized in the subclaims or are shown in more detail below together with the description of the preferred embodiment of the invention with reference to FIGS.

Show it:

1 A block diagram of the process according to the invention for the production of polymeric materials.

In 1 are shown in a block diagram, the process steps of a method according to the invention for the production of polymeric materials W by means of an extruder E in an extrusion process.

In the method, first, the component A, which is a thermosetting plastic polymer in the amount of 90% by weight in the present embodiment, is provided. Component B is metered into component B by means of a gravimetric metering D. Component B in the present embodiment is a thermoset crosslinked recycled fiber in an amount of 9% by weight. Furthermore, the component A is a component C in the form of an additive added in the amount of 1 wt .-%.

As can also be seen, the metered addition of component B is preceded by a production process. First, for this purpose, a waste material containing carbon fibers is provided. Preferably, a waste having a high carbon fiber content of over 30% is provided, the carbon fibers being impregnated and cured with a thermosetting resin system and thus constituting a thermosetting waste. The waste containing the carbon fiber is comminuted by means of mechanical comminution, resulting in the free-flowing thermosetting crosslinked recycled fibers. The recycle fibers thus obtained, which constitute component B, are metered into component A as described above in the production process. From the component mixture of components A, B and C, which are fed to an extruder E, a material is produced, which in the present case represents a profile for a motor vehicle.

In an alternative embodiment, the mixing ratios of the components A, B and C may also differ. So z. B. by increasing the weight proportions of component B, d. H. the thermoset crosslinked carbon fibers, the mechanical stability of the material W are affected.

The invention is not limited in its execution to the above-mentioned preferred embodiments. Rather, a number of variants is conceivable, which makes use of the illustrated solution even with fundamentally different types of use.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 19710098 A1 [0003]

Claims (10)

Plastic granules containing the components A to C, wherein based on the sum of the components A to C, these give a total of 100 wt .-%, wherein Component A is a plastic granulate of a plastic polymer in the amount of up to (100-xy)% by weight; - The component B consists of x wt .-% thermosetting reticulated recycled fibers, which were obtained by comminution, preferably mechanical comminution of a carbon fiber reinforced plastic material; and - The component C from 0 to y wt .-% of function-forming additives such as UV stabilizers, pigments, oxidation retardants, lubricants and mold release agents. A plastic granule mixture according to claim 1, wherein the recycled fibers are carbon fibers obtained by means of a recycling process by comminution from a carbon fiber reinforced plastic waste material. Plastic granulate mixture according to claim 1 or 2, wherein the weight fraction x of carbon fibers is between 10% and 30%. Plastic granulate mixture according to one of claims 1 to 3, characterized in that the component A consists of a thermosetting polymer. Molding composition comprising at least the components A, B and C according to any one of claims 1-4 for processing in an extrusion, coextrusion or Pulstrusionsverfahren. Process for the production of polymeric materials, in particular for use in motor vehicles, comprising at least the following steps: a) supplying a component A of plastic granules of a plastic polymer in the amount of up to (100 - x) wt .-%; b) adding to component A a component B of x wt .-% thermosetting reticulated recycled fibers, which were obtained by mechanical comminution of a carbon fiber reinforced plastic waste material; c) producing a material from the component mixture A and B by means of a plastic processing process. A method according to claim 6, characterized in that the component A is used in the amount (100-xy) wt .-% and further comprises a component C in the amount of 0 to y wt .-% to the components A and B. is metered in and the sum of the components A, B and C results in a total of 100 wt .-%. A method according to claim 6, characterized in that component B is a thermosetting crosslinked carbon fiber and that the metered addition of the amount of component B in step b) is preferably carried out by means of gravimetric addition. Method according to one of claims 6 to 8, characterized in that the component C of function-forming additives such as UV stabilizers, pigments, oxidation retardants, lubricants and mold release agents to the material with the required properties such as color, ductility, UV resistance or others Form material properties. Method according to one of claims 6 to 9, wherein an extrusion, coextrusion or pultrusion method is used for the production of the material.

Images