Composite molded body

Abstract

The invention relates to a molded body substantially containing a fiber composite material which contains a biodegradable polymer as a matrix material and cellulose filaments and / or fibers as a structural component, and to a method for the production thereof.

Description

[0001] CRD3297

[0002] Composite molded bodies

[0003] Description:

[0004] The present application relates to a composite molded body, which could be, for example, a trimmer line, a blade, or a cutting disc for a lawn trimmer, a brush cutter, or a string trimmer. Other applications in the fields of horticulture, nursery, and agriculture are also conceivable, such as for use as a climbing aid.

[0005] The emergence of extensive lawns as a design element of English garden culture in the 18th century necessitated the maintenance of such areas, which was initially carried out primarily with scythes, also commonly used in agriculture at the time. Over time, however, tools specifically designed for this purpose were developed, the current evolution of which is largely reflected in the wide variety of lawnmowers available today. These are particularly suitable for cutting large lawns, and their cutting mechanism typically relies on durable, rotating metal blades. They are also known as "sickle mowers" or "reel mowers."

[0006] For cutting smaller areas of grass, lawn edges, and even tall grass, so-called "lawn trimmers" have become established on the market. These are devices that are typically carried and operated by one person and feature a high-speed cutting blade. Brush cutters and string trimmers work on a similar principle to lawn trimmers, differing primarily in their more powerful engines and more robust cutting blades. Unlike conventional lawnmowers, which use durable, resharpenable metal blades, the cutting blades of lawn trimmers, brush cutters, and string trimmers are typically short-lived wear parts. Due to the high rotational speeds of these devices, sharpening the cutting blades is generally unnecessary.Plant parts such as tall grass, herbs or even smaller bushes are "cut off" by the fast-running cutting tool.

[0007] The cutting tools are often thick plastic threads or wires, made of materials such as polyamide or polyester, which are used particularly in lawn trimmers and are known to experts as "mowing lines" or "trimmer lines." Brush cutters and string trimmers also frequently use wear-resistant blades or cutting discs made of plastic. All these materials have in common that they wear down during use of the respective device and consequently in the environment, and their residues remain there because they are not biodegradable. Thus, larger and smaller plastic parts and particles accumulate in the environment. Below a certain size, such plastic parts are referred to as "microplastics" and are responsible for numerous environmental problems. The remnants of worn cutting tools in lawn trimmers, string trimmers, and brush cutters contribute significantly to the formation of microplastics.To address this problem, various biodegradable trimmer line materials have been proposed, for example in documents EP 4 298 886 A1 and DE 10 2022 213 588 A1. Both documents propose cellulosic long fibers or filaments combined with biodegradable polymers as materials for trimmer line materials. However, in both cases, the biodegradability of the material leaves much to be desired, as polylactic acid (PLA) is very often used as the polymer material. While PLA is biodegradable under industrial conditions, its degradation under environmental conditions is extremely slow. The objective of the present application is therefore to provide a trimmer line, blade, or cutting disc that is more biodegradable than the corresponding components of the prior art.

[0008] The problem is solved by a molded body essentially comprising a fiber composite material, the fiber composite material comprising a biodegradable polymer as a matrix material and cellulosic filaments, characterized in that the molded body optionally also contains cellulosic fibers with a length of 15 mm or less. In one embodiment, the fibers can be shorter than 12 mm, shorter than 10 mm, shorter than 8 mm, shorter than 7.5 mm, shorter than 6 mm, shorter than 5 mm, shorter than 4 mm, shorter than 3 mm, or shorter than 2 mm.

[0009] In one embodiment, the fibers are longer than 1 mm, longer than 2 mm, longer than 3 mm, longer than 4 mm or longer than 5 mm.

[0010] A shaped body within the meaning of the present application is any part made of the aforementioned composite material that can be formed into a shape. In one embodiment, the shaped body is a fiber, a thread, a wire, a rod, a bar, or a plate.

[0011] Fibers are essentially understood to be linear bodies whose diameter is less than one hundredth of their length, with the length of a fiber typically not exceeding 50 cm.

[0012] Filaments are also linear structures that differ from fibers primarily in their length. Specifically, typical filaments are at least one meter long, but can also be considerably longer.

[0013] Filament lengths of several or even many kilometers are not uncommon.

[0014] A wire, as defined in the present application, resembles a filament but differs from it in its thickness and stiffness. A typical wire is stiffer and thicker than a filament. In the present application, a structure with a thickness of less than 2 mm is referred to as a filament and one with a thickness greater than 2 mm as a wire, whereby it is known to those skilled in the art that this is an arbitrary limit. A rod differs from fibers and filaments essentially in its thickness. Unlike fibers and filaments, the thickness of rods is no longer negligibly small compared to their length, and typical rods are rigid and inflexible. Rods can have a wide variety of cross-sectional geometries. For example, round or oval rods are known, as are rods in the form of square, rectangular, triangular, or other polygonal prisms.

[0015] The distinction between rods and bars is fluid. Typically, however, a bar is longer than a rod. In the present application, a structure with a length of less than 50 cm is referred to as a rod, and one with a length of more than 50 cm as a bar, whereby it is known to those skilled in the art that this is an arbitrary boundary.

[0016] Unlike fibers, filaments, wires, rods, and bars, a plate is a shaped body that is not essentially extended in one but in two dimensions. In other words, a plate has both a length and a width that are not negligible. The smallest dimension of a plate is typically its thickness. Plates, as defined in the present application, are generally inflexible or only slightly flexible.

[0017] A plate can have any shape conceivable to an expert. It can be shaped like a cuboid or a wedge, with one edge tapering to a point and possibly sharpened.

[0018] Furthermore, a plate can also be round. In such cases, the term "disc" is often used. Plates or discs within the meaning of the present application may have openings.

[0019] "Containing substantially" within the meaning of this application means that the described composition constitutes a predominant proportion of the molded part, but at least 70% by weight. In one embodiment, the proportion of said composition may be 80%, 85%, 90%, 95%, or 100% by weight. The mass fraction is understood to be the sum of the masses of the biodegradable polymer(s), any cellulosic fibers, and cellulosic filaments contained.

[0020] A matrix material within the meaning of the present application is a material that is in contact with the structural component and stiffens it. In one embodiment, the matrix material can surround the structural component, or the structural component can be embedded in the matrix material. In another embodiment, the structural component is impregnated with the matrix material. It is known to those skilled in the art that the aforementioned embodiments can be combined with one another with respect to the matrix material, and that different materials can be used as matrix materials in one and the same molded body.

[0021] For the purposes of this application, "biodegradable" means that a substance can be completely broken down into substances metabolizable by living organisms through the influence of physical, chemical, and biological environmental factors. Environmental factors include temperature and light, as well as atmospheric oxygen, water, and chemical substances contained in soils, especially humus-rich soils. Biological factors, for the purposes of this application, include those caused by animals and plants, but especially by microorganisms such as algae, bacteria, and fungi. The rate of biodegradability can be highly dependent on environmental conditions. For example, standards AS 5810 and NF T 51-800 define conditions that goods of any kind must meet to be biodegradable under the conditions of typical home composting.In contrast, the standards DIN EN 13432 and ASTM D6400 define biodegradation under industrial conditions such as elevated temperature and humidity.

[0022] Many polymers typically declared as "biodegradable," such as polylactic acid (PLA), only meet the requirements of DIN EN 13432 and are therefore—although in principle biodegradable—still very persistent under environmental conditions, thus posing problems. Biodegradable polymers within the meaning of this application are those polymers that, on their own, meet the requirements of DIN EN 13432 and / or ASTDM D6400 and / or AS 5810 and / or NF T 51-800. In one embodiment, the biodegradable polymer is polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), polyvinyl alcohol (PVA), polybutylene adipate rephthalate (PBAT), natural latex, natural rubber, thermoplastic starch, a biodegradable epoxy resin, a wax, or a polyhydroxyalkanoate (PHA).Furthermore, natural polymers such as lignin or various polysaccharides such as thermoplastic starch or gelatinized starch can also be used, as well as chitin or polymers derived from it such as chitosan or glucosamine. In one embodiment, such polymers are also considered biodegradable within the meaning of the present application if, after mechanical comminution by an insect or other animal, they can be degraded by symbiotic microorganisms in the animal's digestive tract. Such microorganisms are found, for example, in the digestive tract of the dried fruit moth Plodia interpunctella, a known stored-product pest.

[0023] The function of the biodegradable polymer is to stiffen the molded body as defined in the present application and thus impart dimensional stability. In one embodiment, the molded body according to the present application has the appearance of a monolithic object with a completely or largely closed surface and a specific gravity as would typically be expected of plastic components. The proportion of biodegradable polymer contributes significantly to this appearance. In another embodiment, the molded body according to the present application has a textured surface. This surface texturing can, for example, be ribbing or nubs. This texturing can be incorporated into the surface of the matrix material or it can be implemented in another way.If the shaped body as defined in the present application is a twisted thread or cord, texturing can be achieved, for example, by twisting the thread or cord. In that case, the appearance of the shaped body would be similar to that of a twisted rope with a coating. Surface texturing, for example in the form of ribbing, benefits the shaped body for use as a trimmer line according to the present application because the surface texturing enhances the cutting effect. Without committing to a specific theory, it is assumed that the surface texture functions in a similar way to the teeth of a saw.

[0024] In one embodiment, the molded body according to the present application comprises more than one biodegradable polymer as a matrix material. This biodegradable polymer can be an impregnation with which the cellulosic filaments are saturated and which is accordingly also located between the cellulosic filaments. This impregnation can be any biodegradable polymer known to those skilled in the art. Polymer suspensions or emulsions in water or other solvents are advantageous because they have low viscosities and can therefore penetrate well between the cellulosic filaments. Certain groups of such suspensions and emulsions are known to those skilled in the art under the name "latex" or, in the plural, "latices".In one embodiment, the impregnation may consist of natural latex, a product from the rubber tree Hevea brasiliensis, or another source of natural rubber.

[0025] The second biodegradable polymer can be a coating of the impregnated cellulosic filaments. This coating can be any biodegradable polymer known to those skilled in the art, such as polylactic acid (PLA), polycaprolactone (PCL), polybutylene succinate (PBS), polyvinyl alcohol (PVA), polybutylene adipate rephthalate (PBAT), a biodegradable epoxy resin, a wax, natural latex, natural rubber, thermoplastic starch, or a polyhydroxyalkanoate (PHA). Furthermore, natural polymers such as lignin or various polysaccharides like thermoplastic starch or gelatinized starch can also be used, as well as chitin or polymers derived from it, such as chitosan or glucosamine. In addition to the polymers already mentioned, the molded body can also contain other biodegradable polymers according to the present application.In one embodiment, the molded body has several layers of different biodegradable polymers, in particular several layers with varying elasticities. For example, the surface of the cellulosic filaments or the impregnated cellulosic filaments can be coated with a more brittle biodegradable polymer such as polylactic acid, onto which a layer of a more elastic biodegradable polymer such as natural latex is then applied. Multiple layers—regardless of the elasticity of the coating materials—offer advantages with regard to biodegradability, since wear and tear leads to small fractures that provide a surface for microorganisms to attack.

[0026] According to the present application, cellulosic fibers in the molded body act as a filler, reducing the required amount of biodegradable polymer. Furthermore, it has surprisingly been shown that the cellulosic fibers significantly improve the biodegradability of the molded body according to the present application, and in particular of fragments of this molded body that enter the environment through wear and tear. Without committing to a specific theory, it is assumed that the cellulosic fibers, which, unlike the biodegradable polymer, are always biodegradable under environmental conditions, effectively perforate the biodegradable polymer through their own biodegradation.When the cellulosic fibers embedded in the biodegradable polymer degrade, holes and channels remain in the polymer, massively increasing its surface area and providing additional targets for environmental factors such as water, oxygen, and especially microorganisms. In this way, microorganisms can more easily colonize a fragment created, for example, by the wear and tear of a molded part according to the present application, and degrade it more readily and quickly than would normally be the case.

[0027] The cellulosic fibers can be any type of cellulose-based fiber known to those skilled in the art. In particular, plant fibers such as hemp, flax, jute, bagasse, abaca, sisal, ramie, or kapok could be mentioned. The use of wood pulp is also possible. In one embodiment, the cellulosic fibers are finely cut regenerated cellulose fibers, obtained, for example, by the cupro process, the viscose process, the lyocell process, or the Bocell process. In the molded body of the present application, the cellulosic filaments function as the structural element. Embedded in the matrix of the biodegradable polymer, they serve to absorb tensile forces and thus increase the toughness, in particular the impact strength, of the molded body.Impact strength is of particular importance when the molded body is used as a cutting line or blade in a lawn trimmer, brush cutter, or clearing saw, where the cutting action relies essentially on the impact of the blade or cutting line against grass blades, plant stems, twigs, or branches. By incorporating the cellulosic filaments into the molded body according to the present application, both its effectiveness as a cutting line or blade and its service life are generally significantly increased.

[0028] Cellulosic filaments are always produced from wood-based pulp using regeneration processes. In these processes, the pulp, which is pure cellulose derived from wood, is either chemically modified to dissolve in a solvent, or it is treated with a solvent in which it dissolves without further chemical modification. A well-known chemical modification method is the viscose process, in which the pulp, after soaking in sodium hydroxide solution, is treated with carbon disulfide and dissolved in further sodium hydroxide solution. The resulting liquid is forced through spinnerets into an acidic precipitation bath, where the cellulose regenerates, forming cellulose filaments from the liquid jets through precipitation. A similar process is the Bocell process, in which the cellulose is converted into a soluble form by esterification with phosphoric acid.

[0029] The most widespread direct dissolution process is the Lyocell process, in which cellulose is dissolved in N-methylmorpholine N-oxide or similar substances under the influence of high temperatures. By pressing the cellulose into a water bath, it can be precipitated and the N-methylmorpholine N-oxide recovered. In addition, there are direct dissolution processes in which cellulose is dissolved in ionic liquids and subsequently regenerated from these solutions.

[0030] Cellulosic filaments produced using the methods discussed above are characterized by high tensile strength, even under challenging conditions such as high temperatures. It is known to those skilled in the art that such filaments are also referred to as "regenerated cellulose fibers." High temperatures can occur in lawn trimmers, brush cutters, and clearing saws due to friction, but unlike other materials, cellulosic filaments do not lose their strength under these conditions.

[0031] In one embodiment, the cellulosic filaments are contained in the molded body in the form of parallel fibers, yarns, twisted yarns, plies, or cords, or in woven, knitted, braided, or crocheted fabrics made therefrom. In one embodiment, the fibers, yarns, plies, or cords run parallel, so that the increased tensile strength of the molded body is preferably present in one direction. This is particularly the case when the molded body is a fiber, a filament, or a wire.

[0032] In one embodiment, the molded body is a plate or a blade in which the cellulosic filaments are also arranged parallel to each other. In this case, anisotropy results with respect to the tensile strength of the material. In the case of a suitably designed blade, the cellulosic filaments can thus run parallel to the cutting edge of the blade, thereby reinforcing the cutting edge, particularly against wear.

[0033] In one embodiment, the cellulosic filaments are part of a woven, knitted or crocheted fabric and can thus ensure direction-independent reinforcement.

[0034] In one embodiment, the biodegradable polymer, which serves as the matrix material, is foamed. "Foamed" within the meaning of this application means that the polymer contains gas bubbles of at least 0.5 vol.%. In one embodiment, the proportion of gas bubbles is at least 1 vol.%, at least 2 vol.%, at least 5 vol.%, at least 10 vol.%, or at least 25 vol.%. In another embodiment, the proportion of gas bubbles is at most 1 vol.%, at most 2 vol.%, at most 5 vol.%, at most 10 vol.%, at most 25 vol.%, at most 40 vol.%, or at most 60 vol.%. It is important to emphasize that foaming does not necessarily result in increased flexibility. The foaming can be closed-cell foaming, which results in a smooth surface of the molded body.The foaming process can be open-pore, where the surface of the molded part has a roughness due to the open pores, which can be at least 1 pm, or in one embodiment at least 10 pm, at least 50 pm, at least 100 pm, or at least 200 pm. The roughness can be at most 100 pm, at most 200 pm, at most 300 pm, or at most 500 pm.

[0035] The density of the foamed material is at least 0.05 g / cm³. 3 , in one embodiment at least 0.1 g / cm³ 3 , at least 0.2 g / cm³ 3 or at least 0.5 g / cm² 3 The density of the foamed material is at most 0.2 g / cm³. 3 , at most 0.5 g / cm³ 3 , at most 0.7 g / cm³ 3 or at most 1 g / cm² 3 .

[0036] The density loss of the polymer due to foaming is at least 20%, and in one embodiment at least 30%, at least 40%, or at least 50%. The density loss of the polymer due to foaming is at most 40%, and in one embodiment at most 50%, at most 60%, or at most 80%. It has surprisingly been found that the roughness caused by foaming noticeably improves the cutting properties of a trimmer line or blade. Furthermore, it is assumed that the porosity caused by foaming also contributes to an increase in the surface area and thus to the improved biodegradability of the molded body and, in particular, of its fragments, because the pores created by foaming offer additional surface area for microorganisms to attack.

[0037] However, the roughness can also be adjusted by adding other substances that preferably do not impede the compostability of the molded body, such as wood particles, lignin or sand.

[0038] Foaming of the material can be achieved by any method known to a person skilled in the art, for example, by adding a foaming agent. In this context, a foaming agent is understood to be a chemical substance that ideally does not chemically interact with the components of the molded body, but which—for example, due to the high temperature during the melting of the biodegradable polymer—evaporates and thus causes the biodegradable polymer to expand. This could be, for example, a highly volatile hydrocarbon or a compound that decomposes into gaseous products at the melting temperature of the biodegradable polymer. It is also possible to use substances for foaming that are present in the biodegradable polymer as a result of the manufacturing process and therefore may be present as impurities, such as in polycondensation or similar processes.Water formed during chemical reactions and remaining in the polymer.

[0039] In one embodiment, the shaped body according to the present application can be designed as a blade or cutting disc. A blade is a component that is wedge-shaped on one side. Typically, blades exhibit a cutting action on the materials with which they come into contact. This cutting action can be triggered by various factors. Firstly, the cutting action can be based on high kinetic energy with which the blade impacts the material to be cut. In this case, the cutting action corresponds to a striking action and is familiar to those skilled in the art, for example, from kitchen appliances such as food processors or impact coffee grinders, as well as from the action of a hatchet or axe when cutting wood or bone.

[0040] In other cases, the cutting effect is based on the smooth sharpness of the blade, comparable to the effect of, for example, razors or ordinary kitchen knives, which can cut materials even with light contact and slow movement.

[0041] Ultimately, the cutting action of a blade can also be based on its abrasive effect. Blades typically used for this purpose exhibit a visible roughness, which can consist, for example, of teeth or a coating of abrasive materials such as sand, emery, or diamond powder. Typical examples of blades effective due to their abrasive effect, known to those skilled in the art, include the discs of angle grinders, saws used for wood or bone, and serrated knives commonly used for cutting bread. If necessary, the wedge-shaped edge can be sharpened by grinding, etching, or other abrasive treatment to enhance the cutting action.

[0042] In one embodiment, mechanical or chemical sharpening of the blade can improve its cutting performance by enhancing its smooth edge. In another embodiment, the porosity of the blade caused by the foaming can contribute to its abrasive effect, thus improving cutting performance. This effect is inherent, particularly in the case of open-pore foaming, but can be enhanced by mechanical or chemical sharpening. In the case of closed-pore foaming, mechanical and / or chemical sharpening may be necessary to achieve the desired increase in abrasiveness.

[0043] In one embodiment, a self-sharpening function can be achieved by foaming the molded body that forms the blade. This occurs when fragments, pieces, or particles of the blade or trimmer line are detached through wear, opening pores that increase the blade's surface area and thus contribute to its abrasive effect.

[0044] In one embodiment, the shaped body can be a cutting disc. Cutting discs are typically round, flattened bodies with slotted openings whose edges are sharpened like blades.

[0045] The use of cutting discs can be advantageous, for example, with devices used to trim shrubs. In this case, the size of the cutting disc's opening can be a limiting factor for the size of the resulting fragments. Using a cutting disc, shrubs can be shredded during the cutting process and processed into mulch, for example.

[0046] In one embodiment, the trimmer line, blade, or cutting disc according to the present application is formed entirely from the molded body according to the present application and accordingly contains no other materials, in particular no materials that are not biodegradable. In another embodiment, the molded body according to the present application contains, in addition to the aforementioned materials, further substances such as adhesion promoters, which ensure improved adhesion between the cellulosic fibers and filaments on the one hand and the biodegradable polymer on the other. Furthermore, additives such as dyes or pigments are conceivable, the purpose of which may be to make molded bodies such as trimmer lines, blades, or cutting discs with different properties clearly distinguishable.This is particularly advantageous for trimmer line because, due to its small thickness, direct marking is more difficult than with blades or cutting discs.

[0047] In another embodiment, the yarn cohesion in the multifilament yarn can be increased by subjecting the filaments to known processing steps such as twisting, plying, braiding, or knitting. Furthermore, the cohesion can also be achieved (or in combination with these methods) by impregnation with a sticky substance that binds the filaments together.

[0048] These measures can improve both the function and the durability (e.g., of the trimmer line during mowing).

[0049] In one embodiment, the molded body can contain additional fillers, which, for example, serve to adjust the mechanical properties. Possible fillers include minerals such as powdered limestone, for example in the form of chalk, powdered soapstone (also known as talc), or sand. The function of a mineral filler can be, for example, to improve the abrasive properties of the trimmer line, blade, or cutting disc.

[0050] In one embodiment, all other materials contained in a trimmer line, blade, or cutting disc are biodegradable. This does not necessarily apply to mineral fillers, which are nevertheless considered environmentally unproblematic because they are merely, if necessary, pulverized natural products.

[0051] While trimmer line is typically wound onto a spool and inserted into a lawn trimmer, brush cutter, or string trimmer, blades and cutting discs in such devices usually need to be mounted and / or secured. For this purpose, the blades and cutting discs, according to the present application, can have appropriate devices, such as holes through which screws, bolts, or the like can be inserted. The presence of brackets, clamps, or hooks is also possible. To ensure proper function, these components can be made of a different material than the composite material of the present application, for example, iron, steel, or aluminum.However, it is emphasized that, unlike the trimmer line, blade, or cutting disc itself, these components are not designed to wear out and are not intended to be gradually destroyed through contact with the grass or shrubs being cut. Rather, even after a blade or trimmer line breaks, these components remain in the device and can – and usually must – be removed and disposed of properly when a new trimmer line, blade, or cutting disc is installed.

[0052] In one embodiment, a trimmer line according to the present application has a thickness between 0.5 and 8 mm. In another embodiment, the trimmer line is at least 1 mm, at least 1.5 mm, or at least 2 mm thick. In yet another embodiment, the trimmer line is at most 3 mm or at most 4 mm thick.

[0053] The trimmer line according to the present application can have a density in the range of 1,000 to 100,000 dtex. In one embodiment, the density is at least 5,000 dtex, 10,000 dtex, 20,000 dtex, 30,000 dtex, or 40,000 dtex. In another embodiment, the density is at most 50,000 dtex, 60,000 dtex, or at most 70,000 dtex.

[0054] It has also been shown that a cutting line according to the present application results in less unpleasant noise formation when used in a lawn trimmer or brush cutter than a line according to the state of the art.

[0055] The present application further relates to a method for producing a shaped body from fiber composite material comprising the steps of providing a biodegradable polymer, optionally providing cellulosic fibers with a length of 15 mm or less, melting the biodegradable polymer in an extruder, optionally mixing the molten biodegradable polymer with the cellulosic fibers to obtain a mixture, providing cellulosic filaments and co-extruding the mixture with the cellulosic filaments to form a composite material.

[0056] Furthermore, the present application relates to the use of a shaped body according to the present application in the form of a thread or cord as a climbing aid for the cultivation of climbing plants such as hops, which are usually provided with iron wires several meters long, anchored to permanent trellises. To harvest the hop vines, the iron wires are removed from the trellis along with the plants, the hop cones are harvested, and the remaining plant material, including the wires, is then shredded. The shredded material is subsequently applied to the fields as green manure. This leads to specific practical and ecological problems in hop cultivation. These include, firstly, the heavy wear and tear on shredding mills caused by the iron wires, and secondly, the generation of so-called...Hop spikes, 1 to 2 cm long pieces of wire, can cause considerable damage to vehicles in hop-growing areas if they get onto the roads during spreading. Furthermore, spreading the shredded material containing wire remnants results in significant heavy metal contamination.

[0057] A thread according to the present application possesses sufficient tensile strength and stiffness to serve as a climbing aid for hop vines up to seven meters long, while simultaneously being biodegradable in such a way that its use does not cause the aforementioned environmental problems. Furthermore, it is easier to shred, which reduces both energy consumption and wear and tear on shredding machines.

[0058] In addition to use as a thread- or wire-shaped climbing aid, the present application also proposes the use of rigid shaped bodies as climbing aids, for example in the form of poles or rods, or even in the form of trellises composed of such poles or rods. In this case, the climbing aid would be compostable together with the plant climbing on it.

[0059] Another use of the shaped body according to the present application would be its application as a geotextile. In this case, threads, wires, rods, or bars made from the material according to the present application would be assembled into fabrics, nets, or grids capable of, for example, temporarily stabilizing embankments, but which would slowly degrade in the soil under the influence of oxygen, water, and microorganisms. Without being definitively limited to these, the present application relates to the following aspects. It is known to those skilled in the art that all aspects can be combined: i. A shaped body comprising cellulosic filaments as structural material and at least one biodegradable polymer as matrix material. ii. A shaped body according to aspect i), wherein the matrix material additionally contains short cellulosic fibers. iii. A shaped body according to aspect ii), wherein the short cellulosic fibers are a maximum of 15 mm long. iv.A molded body according to one or more of the preceding aspects, wherein the molded body is impregnated with the matrix material. v. A molded body according to one or more of the preceding aspects, wherein the molded body is coated with the matrix material. vi. A molded body according to one or more of the preceding aspects, wherein the matrix material is polylactide, polybutylene succinate, polyhydroxybutyrate, polycaprolactone, a polyhydroxyalkonoate, thermoplastic starch, lignin, natural latex, chitin, chitosan or glucosamine, a biodegradable epoxy resin, or a wax. vii. A molded body according to one or more of the preceding aspects, wherein the molded body contains a second biodegradable matrix material. viii.A molded body according to aspect vii), wherein the second biodegradable matrix material is polylactide, polybutylene succinate, polyhydroxybutyrate, polycaprolactone, a polyhydroxyalkonoate, thermoplastic starch, lignin, natural latex, chitin, chitosan or glucosamine, a biodegradable epoxy resin, or a wax. ix. A molded body according to aspect vii), wherein the first matrix material and the second matrix material are different materials. x. A molded body according to aspect viii) or ix), wherein the molded body is impregnated with one matrix material and coated with another matrix material. xi. A molded body according to one or more of the preceding aspects, wherein one matrix material of the molded body is foamed. xii. A molded body according to one or more of the preceding aspects, wherein the structural material is a yarn. xiii.A shaped body according to aspect xii), wherein the yarn is a twisted yarn. xiv. A shaped body according to aspect xiii), wherein the structure of the twisted yarn creates a surface texture of the shaped body. xv. A shaped body according to one or more of the preceding aspects, wherein the structural material is a knitted, woven, or crocheted fabric. xvi. A shaped body according to one or more of the preceding aspects, wherein the shaped body is a coated and / or impregnated thread. xvii. A shaped body according to aspect xvi), wherein the shaped body has multiple coatings of different biodegradable polymers. xviii. A shaped body according to aspect xvii), wherein the coating materials have different elasticities. xix. A shaped body according to one or more of the preceding aspects, wherein the shaped body is a plate or a disc. xx.A shaped body according to one or more of the preceding aspects, wherein the shaped body is fully biodegradable according to EN 13432, AS 5810 or NF-T 51800. xxi. Use of the shaped body according to one or more of aspects i)- xvii) as a trimmer line or blade in a lawn trimmer, brush cutter or string trimmer. xxii. Use of the shaped body according to one of aspects i)- xviii) as a climbing aid in the form of a cord, a pole or a rod.

Claims

Composite molded bodies Claims:

1. Molded body essentially comprising a fiber composite material, the fiber composite material comprising • A biodegradable polymer as a matrix material, • Cellulosic filaments and / or fibers as a structural component.

2. Molded body according to claim 1 characterized in that the matrix material additionally contains cellulosic fibers with a length of 15 mm or less.

3. Molded body according to claim 1 or 2 wherein the matrix material of the molded body is foamed.

4. Molded body according to one or more of the preceding claims, wherein the biodegradable polymer is polylactide (PLA), polycaprolactone, polyhydroxyalkanoates, natural latex, lignin, polysaccharides, chitin, chitosan, polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polybutylene succinate (PBS), a biodegradable epoxy resin, a wax or thermoplastic starch.

5. Molded body according to one or more of the preceding claims, wherein the molded body contains at least one second biodegradable polymer, preferably one selected from polylactic acid (PLA), Polycaprolactone, polyhydroxyalkanoates, natural latex, lignin, polysaccharides, chitin, chitosan, polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polybutylene succinate (PBS), a biodegradable epoxy resin, a wax or thermoplastic starch.

6. Molded body according to one or more of the preceding claims, wherein the cellulosic filaments are impregnated with the biodegradable polymer.

7. Molded body according to one or more of the preceding claims, wherein the cellulosic filaments are coated with at least one second biodegradable polymer.

8. Molded body according to one or more of the preceding claims, wherein the cellulosic filaments are in the form of at least one chamois, preferably a twisted chamois, in the form of at least one cord, preferably a twisted cord, or in the form of a woven, braided, knitted or crocheted fabric of yarns, twisted yarns, cords or twisted cords.

9. Molded body according to one or more of the preceding claims, wherein the cellulosic fibers and / or cellulosic filaments are regenerated cellulose fibers such as viscose or lyocell or regenerated cellulose fibers produced using ionic liquids.

10. Molded body according to one or more of the preceding claims, wherein the molded body is a linear structure, such as a thread, a yarn or a wire, preferably a trimmer line, or a blade or a cutting disc for a lawn trimmer, a brush cutter or a brush cutter.

11. Molded body according to one or more of the preceding claims, wherein the molded body is fully biodegradable according to EN 13432, ASTM D 6400, AS 5810 or NF-T 51800.

12. Method for producing a shaped body from fiber composite material comprising the steps • Providing one or more biodegradable polymers, • Application of the biodegradable polymer(s) onto a linear structure, possibly in several process steps 13. Method for producing a shaped body from fiber composite material comprising the steps • Providing a biodegradable polymer, • Providing cellulosic fibers with a length of 5 mm or less • Melting the biodegradable polymer in an extruder, • Mixing the molten biodegradable polymer with the cellulosic fibers to obtain a mixture, • Providing cellulosic filaments, optionally obtained according to the method of claim 12 • Co-extruding the mixture with the cellulosic filaments to form a composite material.

14. The method according to claim 12 or 13, wherein fibers or wires, preferably weeding threads, are produced.

15. The method according to claim 13, wherein the co-extrusion and subsequent granulation and injection molding of the component (and optionally, Post-processing) shaped bodies, preferably blades or cutting discs, are produced.

16. Cutting line, blade or cutting disc for a brush cutter, lawn trimmer or string trimmer, comprising a shaped body according to one or more of claims 1 to 11, wherein the cutting line is fully biodegradable according to EN 13432 and / or ASTM D 6400 and / or AS 5810 and / or NF T 51800.