DE102022126382A1 - Layered composite material with shape memory polymers and process for its manufacture - Google Patents

Abstract

A layered composite material and a method for its production are proposed, which has a first flat layer that can be deformed between a first and second shape and a second flat layer made of thermoplastic polymers that is applied to it and can be deformed at least between a first and second shape. The second layer is deposited on the first layer using melt layers, wherein the invention provides that at least one of the layers is produced using melt layers of a thermoplastic polymer with thermo- or water-responsive shape memory properties, which on the one hand has hard segments with a melting transition temperature range and on the other hand has soft segments with a glass transition or melting temperature range that is below the melting transition temperature range of the hard segments. The thermoplastic shape memory polymer of the respective layer is deposited during melt layering to form the layer in a first shape and programmed into a second shape in such a way that the layer is switched into the second shape when heated to the glass transition or melting temperature range of the soft segments of the shape memory polymer or when it comes into contact with water.

Description

1. (a) wenigstens eine erste, im Wesentlichen flächige und zumindest zwischen einer ersten Form und einer zweiten Form verformbare Lage, und
2. (b) wenigstens eine, zumindest bereichsweise auf die erste Lage aufgebrachte zweite, im Wesentlichen flächige und zumindest zwischen einer ersten Form und einer zweiten Form verformbare Lage aus wenigstens einem thermoplastischen Polymer,

wobei die wenigstens eine zweite Lage mittels Schmelzschichten zumindest bereichsweise auf der wenigstens einen ersten Lage abgeschieden wird. Die Erfindung bezieht sich ferner auf ein mittels eines solchen Verfahren herstellbares lagenförmiges Verbundmaterial, umfassend

1. (a) wenigstens eine erste, im Wesentlichen flächige und zumindest zwischen einer ersten Form und einer zweiten Form verformbare Lage, und
2. (b) wenigstens eine, zumindest bereichsweise auf die erste Lage aufgebrachte zweite, im Wesentlichen flächige und zumindest zwischen einer ersten Form und einer zweiten Form verformbare Lage aus wenigstens einem thermoplastischen Polymer,

wobei die wenigstens eine zweite Lage zumindest bereichsweise auf die wenigstens eine erste Lage aufgebracht ist.The invention relates to a method for producing a layered composite material comprising

1. (a) at least one first, substantially planar layer deformable at least between a first shape and a second shape, and
2. (b) at least one second, substantially planar layer made of at least one thermoplastic polymer, applied at least partially to the first layer and deformable at least between a first mold and a second mold,

wherein the at least one second layer is deposited at least partially on the at least one first layer by means of melt layers. The invention further relates to a layered composite material that can be produced by means of such a method, comprising

1. (a) at least one first, substantially planar layer deformable at least between a first shape and a second shape, and
2. (b) at least one second, substantially planar layer made of at least one thermoplastic polymer, applied at least partially to the first layer and deformable at least between a first mold and a second mold,

wherein the at least one second layer is applied at least partially to the at least one first layer.

Such layered composite materials are known in particular in the form of so-called 4D textiles, which have a first flat layer made of a textile material under tension that is elastically deformable. A second layer made of thermoplastic polymers is applied to the first layer of the textile material, which is usually done by means of melt layers of the second layer using 3D printers on the first layer of the textile material, which is put under tension during the melt layering by means of suitable pre-tensioning devices. The second layer can be applied to the first layer of the textile material with a different thickness in some areas and/or in particular only in some areas. Due to the fact that the first layer of textile material was placed under tension during the application of the second layer to the first layer, such a composite material is capable of changing shape during subsequent relaxation of the textile material, which is inhibited depending on the thickness and/or local presence of the second layer, whereby it is more or less automatically deformed from its previously essentially flat shape into a three-dimensional surface structure, for example after a certain period of time and/or as a result of external influences such as moisture, light, heat or the like. Areas of application for such 3D textiles include, for example, the fashion industry, but also medical technology or other technical fields, such as aerospace (see, for example, https://www.stylepark.com/de/news/techtextil-2019-4d-textilien, downloaded on 06.10.2022 ).

Controlling the desired shape recovery during the relaxation of such 4D textiles is currently still the subject of research and is proving to be extremely complex. For example, pre-tensioning the first layer of textile material can lead to the occurrence of inhomogeneous stress fields, which is why this technology is currently only partially controllable and requires the use of complex pre-tensioning devices. In addition, control of the change in shape is limited by the degree of stretch introduced into the textile material and by the thickness and/or shape of the second layer of thermoplastic polymer materials, which is printed on in particular only in certain areas.

The invention is based on the object of developing a layered composite material of the type mentioned at the outset in a simple and cost-effective manner such that an exact shape change behavior of the composite material can be set while at least largely avoiding the aforementioned disadvantages. The invention is also directed to a method for producing such a layered composite material.

• - Hartsegmente mit wenigstens einem Schmelzübergangstemperaturbereich, andererseits
• - Weichsegmente und/oder Mischphasen aus Weichsegmenten und und Hartsegmenten mit einem unterhalb des Schmelzübergangstemperaturbereiches der Hartsegmente gelegenen Glasübergangs- oder Schmelztemperaturbereich

aufweist, erzeugt wird, wobei das wenigstens eine thermoplastische Polymer mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften der wenigstens einen Lage während des Schmelzschichtens zu der wenigstens einen Lage in einer ersten Form abgeschieden und derart in wenigstens eine zweite Form programmiert wird, dass die wenigstens eine Lage bei Erwärmen auf den Glasübergangs- oder Schmelztemperaturbereich der Weichsegmente des wenigstens einen thermoplastischen Polymers mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften und/oder bei Kontakt mit Wasser in die wenigstens eine zweite Form geschaltet wird.In terms of process engineering, this object is achieved in a method for producing a layered composite material of the type mentioned at the outset in that at least one of the layers is bonded by means of melt layers of at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, which on the one hand

• - Hard segments with at least one melting transition temperature range, on the other hand
• - Soft segments and/or mixed phases of soft segments and hard segments with a melting transition temperature range below the hard segments Glass transition or melting temperature range

wherein the at least one thermoplastic polymer having thermoresponsive and/or water-responsive shape memory properties of the at least one layer is deposited in a first shape during melt layering to form the at least one layer and is programmed into at least one second shape such that the at least one layer is switched into the at least one second shape upon heating to the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer having thermoresponsive and/or water-responsive shape memory properties and/or upon contact with water.

• - Hartsegmente mit wenigstens einem Schmelzübergangstemperaturbereich, andererseits
• - Weichsegmente und/oder Mischphasen aus Weichsegmenten und Hartsegmenten mit einem unterhalb des Schmelzübergangstemperaturbereiches der Hartsegmente gelegenen Glasübergangs- oder Schmelztemperaturbereich

aufweist, wobei das wenigstens eine thermoplastische Polymer mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften der wenigstens einen Lage in einer ersten Form vorliegt und derart in wenigstens eine zweite Form programmiert ist, dass die wenigstens eine Lage bei Erwärmen auf den Glasübergangs- oder Schmelztemperaturbereich der Weichsegmente des wenigstens einen thermoplastischen Polymers mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften und/oder bei Kontakt mit Wasser in die wenigstens eine zweite Form geschaltet wird.In terms of product technology, the invention further provides for the solution of this problem in a layered composite material of the type mentioned above that can be produced by means of such a method, that at least one of the layers has at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, which on the one hand

• - Hard segments with at least one melting transition temperature range, on the other hand
• - Soft segments and/or mixed phases of soft segments and hard segments with a glass transition or melting temperature range below the melting transition temperature range of the hard segments

wherein the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is present in a first shape and is programmed into at least one second shape such that the at least one layer is switched into the at least one second shape upon heating to the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties and/or upon contact with water.

Polymers with shape memory properties, so-called shape memory polymers, are polymers that often consist of two or more phases or segments. On the one hand, these are hard segments, which also act as network points between neighboring polymer molecules and have a melting transition temperature range above which the polymer is completely melted and can be processed using practically any known thermoplastic processing method. On the other hand, they are soft segments and/or mixed phases of soft segments and hard segments, which connect the network points to one another and are also referred to as "switching segments". It should be noted, however, that the network points of generic thermoplastic polymers with shape memory properties are not chemically cross-linked areas, but are primarily physical in nature. The soft segments or the mixed phases of soft segments and hard segments are primarily elastic at elevated temperatures above their glass transition or melting temperature range (in this case they are primarily in amorphous form) or they are at least partially plasticized above their melting temperature range, while they are rigid at lower temperatures below their glass transition temperature range (in this case they are primarily in vitrified or partially crystalline form).

Such shape memory polymers can be programmed in terms of their shape by heating them to a so-called switching temperature, which corresponds at least to the glass transition or melting or crystallization temperature range of the soft segments or the mixed phases of soft segments and hard segments, but is more or less significantly below the melting transition temperature range of the hard segments, and at which the phase transition (glass transition or melting transition) of the soft or switching segments takes place. At such a temperature, the shape memory polymer can then be deformed under the influence of external deformation forces, after which it is cooled to its so-called shape fixing temperature while maintaining the deformation, which in turn can be in the glass transition or crystallization temperature range of the soft or switching segments, but is usually at least somewhat lower. The soft or switching segments are then again in vitrified or partially crystalline form, so that the shape is retained. However, this shaping is only temporary insofar as when a shape memory polymer that has been mechanically deformed in such a "programmed" manner is heated to a certain temperature, namely to its switching temperature, the soft segments or the mixed phases of soft segments and hard segments (switching segments) are converted back into their predominantly amorphous form, so that they can no longer counteract the restoring force induced by the hard segments (network points) and the shape memory polymer returns to its original, also referred to as "permanent" shape. the mechanical deformation is therefore "reversed" during programming. Furthermore, it is often possible to program by cold forming, in which the shape memory polymers are deformed at a temperature below their switching temperature, e.g. at ambient temperature, and if necessary, if the shape fixing temperature is lower, cooled to their shape fixing temperature. In this case too, only temporary deformation takes place, as re-deformation takes place when the polymer is heated again, at least to the switching temperature, in order to convert the soft segments or the mixed phases of soft segments and hard segments (switching segments) into the predominantly amorphous phase and to relax the mechanical stresses induced by the cold forming.

In addition to such a shape memory, thermoresponsive shape memory polymers also have a temperature memory. This means that when the shape memory effect is triggered, the shape recovery begins at approximately the temperature - usually in the glass transition or melting temperature range of the soft or switching segments - at which the mechanical deformation was previously introduced into the material. Polymers with semi-crystalline network structures, such as thermoplastic polyurethane elastomers ( N. Fritzsche, T. Pretsch in Macromolecules 47, 2014, 5952-5959; N. Mirtschin, T. Pretsch in RSC Advances 5, 2015, 46307-46315 ). In the case of water-responsive shape memory polymers, the shape recovery can also be triggered by contact with water or aqueous solutions, in that the soft or switching segments are also softened so that they can no longer counteract the restoring force induced by the hard segments (network points) and the shape memory polymer is returned from its previously programmed shape to its original shape. Both thermo- and water-responsive shape memory polymers are described, for example, in the patent application not yet published at the priority date of the present patent application. EN 10 2022 125 583.2 in the form of polyether polyurethanes and in this case contain, on the one hand, hard segments which contain polyurethane units which have been obtained by polyaddition of the isocyanate groups of a diisocyanate with the hydroxy groups of a diol serving as a chain extender to form urethane groups, and, on the other hand, soft segments which contain polyether units in the form of polyalkylene glycols or are formed entirely from them, the polyether units being connected to terminal isocyanate groups of the diisocyanate of the hard segments to form urethane groups.

In addition to shape memory polymers, which can only be switched once from their programmed (temporary) form to their original (permanent) form and are also referred to as “one-way shape memory polymers”, polymers with two-way shape memory properties are also known. The latter can be switched back and forth thermoreversibly between at least two forms several times by the soft or switching segments of such two-way shape memory polymers undergoing a change in shape during the transition between their predominantly semi-crystalline state and their predominantly amorphous state in such a way that they can be reversibly switched back and forth between two bistable shape states by cooling the polymer below the crystallization temperature on the one hand and by heating the polymer to the melting temperature range on the other hand, i.e. the correspondingly programmed polymer deforms back and forth automatically when the temperature is controlled accordingly. Such two-way shape memory polymers are made of, for example, T. Pretsch, M. Bothe: “Bidirectional actuation of a thermoplastic polyurethane elastomer”, Journal of Materials Chemistry A, 20 (2013), 14.491-14.497 known.

While thermoplastic polymers with shape memory properties, as already mentioned, can largely be processed by means of conventional thermoplastic processing methods, such as extrusion, injection molding, hot pressing, etc., whereby they can be plasticized, for example, in a plasticizing unit like an extruder and discharged from the plasticizing unit by means of an outlet nozzle or a nozzle unit, some of such thermoplastic polymers with shape memory properties can also be processed by means of the melt layer process, as is used in particular in 3D printers. This melt layer process, also known as "fused deposition modeling" (FDM) or "fused filament fabrication" (FFF), is a manufacturing process in which one or more filaments or granules made of the thermoplastic polymer or of a polymer blend of thermoplastic polymers with shape memory properties are plasticized in a plasticizing unit of the 3D printer and deposited layer by layer using an outlet nozzle usually provided in the print head of the 3D printer in order to produce the layer ultimately formed from a large number of such layers or "drops". In the melt layer process using 3D printing, also known as "additive manufacturing", a three-dimensional model of the layer to be produced is usually created digitally, which is particularly possible using the known methods of computer Aided Designs (CAD). In addition, using suitable software, such as a so-called slicer program (e.g. Cura™ or the like), the three-dimensional model of the layer to be produced is broken down into a number of thin layers, whereupon the plasticized polymer is deposited layer by layer using the outlet nozzle of the correspondingly moved print head in order to build up the layer layer by layer. Immediately after the polymer plasticized material is discharged from the outlet nozzle of the print head in more or less strand or droplet form, the curing process begins - or more precisely: the solidification process - whereby the deposited plasticized material solidifies, for example, at ambient temperature or with active cooling. A method for producing thermoplastic polymer molded parts with shape memory properties in the melt layer process using 3D printers is known in particular from the EN 10 2019 007 939 A1 which is hereby explicitly made the subject of the present disclosure.

The invention now provides that at least one of the layers - be it the at least one first layer and/or the at least one second layer - of the layered composite material is produced by means of melt layers of at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, wherein at least one polymer with shape memory properties or a polymer blend containing at least one such polymer is used, which on the one hand has hard segments with at least one melting transition temperature range, and on the other hand has soft segments and/or mixed phases of soft segments and hard segments with a glass transition or melting temperature range below the melting transition temperature range of the hard segments. According to the invention, the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is deposited in a first (in the case of a disposable shape memory polymer, temporary) shape during melt layering to form the at least one layer and is programmed into at least one second (in the case of a disposable shape memory polymer, permanent) shape such that the at least one layer is switched into the at least one second shape when heated to the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties and/or when in contact with water.

The design according to the invention not only makes it unnecessary to tension the first layer, as is necessary when producing 4D textiles in order to ensure a subsequent change in shape of the layered composite material, but also offers, as explained in more detail below, the possibility of a large number of material combinations for the first and second layers, whereby the desired change in shape of only one (the other layer is then at least partially deformed during the shape recovery) or both layers (both layers are deformed in a similar or different way during the shape recovery) can be programmed in a variety of ways by means of the thermoplastic shape memory polymer, in order in particular to produce very complex surface structures when the shape memory effect of at least one of the layers is triggered. In this case, it is also possible according to the invention to form both the at least one first layer and the at least one second layer of the layered composite material from thermoplastic polymers, at least one of which has shape memory properties, so that a material bond is created between the layers and any delamination is reliably prevented. As mentioned above, the shape memory effect can be triggered either thermally, when the at least one thermoplastic polymer with thermoresponsive properties of the at least one layer is heated to the range of the glass transition or melting temperature of its soft segments, and/or as a result of contact with water or aqueous solutions, when the at least one thermoplastic polymer with water-responsive properties of the at least one layer is exposed to such a medium, so that the composite material according to the invention can be given mono- or dual stimuli-responsive properties.

According to the invention, at least one thermoplastic polymer with shape memory properties of at least one of the layers can be selected from the group of one-way or two-way shape memory polymers, as described above. The at least one thermoplastic polymer with shape memory properties of the at least one layer of a layered composite material according to the invention can thus be a one-way or a two-way shape memory polymer.

Examples of suitable thermoplastic polymers with thermo- and/or water-responsive shape memory properties include linear block copolymers, preferably polyurethanes and polyurethanes with ionic or mesogenic components, block copolymers of polyethylene lenterephthalate and polyethylene oxide, block copolymers of polystyrene and poly(1,4-butadiene), ABA triblock copolymers of poly-(2-methyl-2-oxazoline) (A block) and polytetrahydrofuran (B block), multiblock copolymers of polyurethanes with poly(ε-caprolactone) switching segments, block copolymers of polyethylene terephthalate and polyethylene oxide and block copolymers of polystyrene and poly(1,4-butadiene). Furthermore, thermoplastic polyurethane elastomers have proven to be suitable, the phase forming the hard segment of which is composed of a diisocyanate, such as methylene diphenyl diisocyanate (MDI), isophorone diisocyanate (IPDI), 1,6-hexamethylene diisocyanate (HMDI), toluene-2,4-diisocyanate (TDI) or 1,5-pentane diisocyanate (PDI), isophorone diisocyanate (IPDI), naphthylene diisocyanate (NDI) and polymeric diphenylmethane diisocyanate (PMDI) including mixtures thereof, and a diol, such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol or 1,10-decanediol. Both the diisocyanates mentioned and the polyols can be used individually or in any mixture with each other.

The soft segment in such thermoplastic polyurethane elastomers can be, for example, an oligoether, in particular polyethylene oxide, polypropylene oxide, polytetramethylene ether glycol (PTMEG) or a combination of 2,2-bis(4-hydroxyphenyl)propane and propylene oxide. The soft segment can also be, for example, an oligoester, in particular polyethylene adipate, polypropylene adipate, polybutylene adipate, polypentylene adipate or polyhexalene adipate, although other oligoesters have also proven useful. The oligoesters can be prepared, for example, by reacting ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol or 1,10-decanediol with aliphatic dicarboxylic acids, such as succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid and sebacic acid, or with aromatic dicarboxylic acids, such as phthalic acid, isophthalic acid and terephthalic acid. The dicarboxylic acids can be used individually or as mixtures, e.g. in the form of a succinic, glutaric and adipic acid mixture. To produce the polyester polyols, it may be advantageous to use the corresponding dicarboxylic acid derivatives, such as carboxylic acid diesters with 1 to 4 carbon atoms in the alcohol radical, carboxylic acid anhydrides or carboxylic acid chlorides, instead of dicarboxylic acids. Examples of polyhydric alcohols include glycols with 2 to 10, preferably with 2 to 6, carbon atoms, ethylene glycol, diethylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,10-decanediol, 2,2-dimethyl-1,3-propanediol, 1,3-propanediol and dipropylene glycol. The polyhydric alcohols can be used alone or optionally in a mixture with one another. The polyester polyols also advantageously have molecular weights between about 400 and about 10,000 g/mol, preferably between about 600 and about 5,000 g/mol. If the thermoplastic shape memory polymer of the at least one layer is to have water-responsive properties, shape memory polymers have also proven particularly useful whose soft segments contain polyether units in the form of polyalkylene glycols, such as polyethylene glycol (PEG), polypropylene glycol (PPG), polytetramethylene ether glycol (PTMEG) and the like, or are formed entirely from them, wherein the hard segments can in turn be formed from polyurethane units which have been obtained by polyaddition of the isocyanate groups of at least one diisocyanate of the above-mentioned type with the hydroxy groups of at least one diol of the above-mentioned type serving as a chain extender to form urethane groups, as described, for example, in the patent application not yet published at the priority date of the present patent application. EN 10 2022 125 583.2 are described.

In addition, polycarbonate-based polyurethane elastomers, for example, can be considered as thermoplastic polymers with shape memory properties. In this case, the diol used for the soft segments or switching segments in a thermoplastic polyurethane elastomer is preferably substantially completely or partially substituted by a polycarbonate having hydroxyl end groups, i.e. by a polycarbonatediol, which is obtained from the reaction of a diol, in particular from the group ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol and 1,10-decanediol, with diaryl carbonates, such as diphenyl, ditolyl, dixylyl, dinaphthyl carbonate, dialkyl carbonates, such as diethyl, dipropyl, dibutyl, diamyl, dicyclohexyl carbonate, Dioxolanones, such as ethylene and propylene carbonate, hexanediol-1,6-bischlorocarbonic acid ester, phosgene or urea. Furthermore, for the soft or switching segments in such polycarbonate-based polyurethane elastomers, for example polycaprolactones, polyglycolides and/or polyhydroxyalkanoates, preferably with a molecular weight between about 400 g/mol and about 4000 g/mol, can be used.

In addition, particularly in thermoplastic polyurethane elastomers with shape memory properties, the chain extender diol can be partially substituted by a diamine. Examples of these include isophoronediamine, ethylenediamine, 1,2-propylenediamine, 1,3-propylenediamine, N-methyl-1,3-propylenediamine, N,N'-dimethylethylenediamine and aromatic diamines such as 2,4-toluenediamine and 2,6-toluenediamine, 3,5-diethyl-2,4-toluenediamine and/or 2,6-toluenediamine and primary ortho-di-, tri- and/or tetraalkyl-substituted 4,4'-diaminodiphenylmethanes. The diamines mentioned can also be used individually or in any mixture with one another. Diamines are generally not suitable as sole chain extenders because the resulting polyureas cannot be processed thermoplastically or have insufficient shape memory properties.

As already indicated, an advantageous embodiment of the method according to the invention provides that at least the at least one second layer is deposited on the at least one second layer by means of melt layers using at least one 3D printer, whereby of course - as explained in more detail below - the first layer itself can also be produced by means of 3D printing, especially if only or also the first layer contains at least one thermoplastic shape memory polymer.

• - auf eine maximale Temperatur unterhalb der oberen Grenztemperatur des Schmelzübergangstemperaturbereiches seiner Hartsegmente erwärmt wird, so dass die Hartsegmente nicht vollständig aufgeschmolzen werden, und/oder
• - mittels eines geeigneten Bewegungsprofils des Druckkopfes eines 3D-Druckers abgeschieden wird, wonach die wenigstens eine Lage auf eine Temperatur unterhalb dem Glasübergangs- oder Schmelztemperaturbereich der Weichsegmente des wenigstens einen thermoplastischen Polymers mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften abgekühlt wird.

Letzteres kann beispielsweise mittels geeigneter Kühleinrichtungen einschließlich einer Kühlung des Drucktisches geschehen, um das wenigstens eine Formgedächtnispolymer möglichst schnell auf eine Formfixierungstemperatur unterhalb dem Glasübergangs- oder Schmelzbereich der Weichsegmente abzukühlen; darüber hinaus kann z.B. die Bauraumtemperatur des Druckers entsprechend variiert werden.While the at least one shape memory polymer of the at least one layer can in principle only be programmed after the layered composite material has been produced, it can be provided in an advantageous embodiment that the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is programmed to its second shape during the melt layering by

• - is heated to a maximum temperature below the upper limit temperature of the melting transition temperature range of its hard segments, so that the hard segments are not completely melted, and/or
• - is deposited by means of a suitable movement profile of the print head of a 3D printer, after which the at least one layer is cooled to a temperature below the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties.

The latter can be done, for example, by means of suitable cooling devices including cooling of the printing table in order to cool the at least one shape memory polymer as quickly as possible to a shape fixing temperature below the glass transition or melting range of the soft segments; in addition, for example, the build chamber temperature of the printer can be varied accordingly.

In this way, it is possible to program the at least one thermoplastic polymer with shape memory properties into the second (in the case of a disposable shape memory polymer, for example, temporary) shape together with the production of the respective layer of the layered composite material - or more precisely: during the 3D printing process - i.e. it is brought into its second shape during its shaping, from which it can then later be switched into its first (in the case of a disposable shape memory polymer, for example, permanent) shape when the at least one thermoplastic polymer with shape memory properties is heated at least to or expediently above the switching temperature or the glass transition or melting temperature of its soft segments, but below the melting transition temperature range of its hard segments. This is possible because, due to the incomplete melting of at least the hard segments, the physical network points of the thermoplastic polymer with shape memory properties are not completely melted either, while the thermoplastic processing to form the respective layer simultaneously introduces shear and thrust forces into the plasticized polymer material. After exiting the outlet nozzle of the plasticizing unit and after cooling to a temperature below the glass transition or melting temperature range of the soft segments or the mixed phases of soft and hard segments, the deformations introduced into the polymer material as a result of these mechanical forces, such as in the form of expansion, are fixed by the vitrification or crystallization of the soft segments or the mixed phases of soft and hard segments (switching segments) and in this way a shape memory effect, in particular a thermoresponsive one, is imprinted. The cooled layer then remains in its first shape, which was given to it during its production by means of 3D printing, until it is heated to or to a temperature above the glass transition or melting temperature range of the soft segments or above the switching temperature, whereupon the respective layer is converted into its second form without the application of mechanical forces. The respective layer thus has a functional integration in the sense of thermoresponsiveness, whereby the particularly three-dimensional sional deformation of the layered composite material can be preset by appropriately programmed shape recovery of the first and/or second layer. If the at least one thermoplastic shape memory polymer of the respective layer has water-responsive properties, the same applies in the event of exposure of the layered composite material to water or aqueous solutions.

• - die in einer Plastifiziereinheit und/oder in einer Austrittsdüse des 3D-Druckers eingestellte Temperatur, und/oder
• - der in einer Plastifiziereinheit und/oder in einer Austrittsdüse des 3D-Druckers eingestellte Druck, und/oder
• - die Plastifikatstränge des wenigstens einen thermoplastischen Polymers mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften während und/oder nach ihrem Ausbringen aus dem wenigstens einen Druckkopf des 3D-Druckers auf einer Temperatur im oder oberhalb dem Glasübergangs- oder Schmelztemperaturbereich der Weichsegmente gehalten und verformt werden, indem die Richtung und/oder der Betrag der Relativgeschwindigkeit des Druckkopfes in Bezug auf einen Drucktisch des 3D-Druckers gesteuert wird bzw. werden.

In addition, the extent of the shape recovery behavior of the respective layer between the first form and the second form of the layered composite material according to the invention can be controlled by the temperature set in the plasticizing unit and/or in the outlet nozzle of the 3D printer and/or by the pressure set therein as well as by the geometry of the outlet nozzle, the former ensuring the incomplete melting of the hard segments, while the latter can be used to introduce mechanical forces of different magnitudes and/or directions into the not completely melted polymer material. A further possibility of programming the at least one thermoplastic shape memory polymer together with the production of the respective layer consists in controlling the direction and/or the amount of the relative speed of the print head in relation to a printing table of the 3D printer carrying the layer(s), whereby in particular shear forces can be introduced into the polymer plasticized material, which are "frozen" by subsequent cooling at least to the shape fixing temperature below the glass transition or crystallization temperature of the soft segments. In a preferred embodiment, it can therefore be provided that the programmed shape recovery capacity of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is set by

• - the temperature set in a plasticizing unit and/or in an exit nozzle of the 3D printer, and/or
• - the pressure set in a plasticizing unit and/or in an exit nozzle of the 3D printer, and/or
• - the plastic strands of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties are held at a temperature in or above the glass transition or melting temperature range of the soft segments during and/or after their discharge from the at least one print head of the 3D printer and are deformed by controlling the direction and/or the amount of the relative speed of the print head with respect to a print table of the 3D printer.

Furthermore, it should be explicitly pointed out at this point that the method according to the invention also opens up the possibility, for example, of jointly processing two or more thermoplastic polymers with shape memory properties, which can have different glass transition or melting temperatures of their soft segments and/or their mixed phases of soft and hard segments or different switching temperatures. In this way, on the one hand, it is possible to specifically set the switching temperatures for the phase transitions of a layer of the layered composite material produced in this way; on the other hand, alternatively or additionally, by influencing the heat transport in different areas of the respective layer, a time-dependent switching, i.e. a time-dependent region-by-region deformation of the respective layer from the first shape caused by the manufacturing process into the second shape, can be triggered, whereby in conjunction with the at least two layers lying against one another, highly complex three-dimensional surface structures can be produced. For these purposes, for example, polymer blends or polymer mixtures made of thermoplastic shape memory polymers can be used, or when producing the respective layer by means of the melt layer process using 3D printers, for example, several printing filaments or granules made of different polymers can be used (so-called “multi-material printing”), whereby at least one or all of these polymers are thermoplastic shape memory polymers.

As already indicated, the at least one second layer produced by means of melt layers can only be deposited in regions on the at least one first layer, such as in particular in the form of geometric structures, e.g. essentially in the form of band-shaped, ring-shaped, polygonal or other types of structures, in order to ensure only local deformation (if at least the second layer is produced from shape memory polymers) and/or to provide local resistance to shape recovery of the first layer (if at least the first layer is produced from shape memory polymers). Instead, it is also possible to deposit the at least one second layer produced by means of melt layers essentially over the entire surface on the at least one first layer, wherein the thickness of the at least one second layer (as well as the at least one first layer) can be kept essentially constant in both cases or can also be varied.

In a layered composite material according to the invention, it can therefore be provided that the at least one second layer is applied to the at least one first layer only in some areas, in particular in the form of geometric structures, such as those of the aforementioned type, or essentially over the entire surface, wherein the thickness of the layer(s) can be essentially constant or a respective layer can have different thicknesses in order to ensure, for example, a weaker or stronger change in shape in local areas.

The method according to the invention opens up a multitude of possible method variants in that only the at least one first layer, only the at least one second layer or even both layers can be designed from programmed shape memory polymers, wherein in particular the shape and/or thickness of the layer(s) can also be varied, so that a multitude of possible three-dimensional surface structures can be produced when the shape memory effect of the respective shape memory polymer is triggered.

Thus, according to a first method variant, it can be provided that only the at least one second layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it in a first, e.g. essentially planar, shape on the at least one first layer using melt layers and programming it into at least one second shape. In this way, only the second layer - whether it is applied to the first layer only in regions or essentially over the entire surface and/or whether it is designed with an essentially constant or variable thickness - is given a shape recovery capacity, which the first layer can counteract to varying degrees depending on the material and thickness in order to ensure shape changes of the layered composite material of varying extents, primarily in regions or practically completely.

• - eine Lage aus wenigstens einem, insbesondere thermoplastischen, Polymer ohne Formgedächtniseigenschaften, vorzugsweise aus der Gruppe der Elastomere, oder
• - eine Lage aus wenigstens einem Textilmaterial

verwendet werden, wobei die erste Lage in jedem Fall eine hinreichende - plastische oder elastische - Verformbarkeit aufweisen sollte, um anlässlich der Formrückstellung der zweiten Lage zumindest teil- bzw. bereichsweise (mit) verformt zu werden.In this case, at least a first layer can be

• - a layer of at least one, in particular thermoplastic, polymer without shape memory properties, preferably from the group of elastomers, or
• - a layer of at least one textile material

The first layer should in any case have sufficient - plastic or elastic - deformability to be at least partially or regionally deformed when the second layer returns to its shape.

Instead, in this case, at least one layer can be, for example, a layer made of at least one, in particular thermoplastic, polymer with shape memory properties, which is not programmed, but can itself be programmed into a further shape, in particular when the second layer returns to its shape. The deformation forces required to program the shape memory polymer of the first layer are applied by the shape recovery of the second layer when the shape memory effect of at least one shape memory polymer is triggered (e.g. when it is heated to the range of its glass transition or melting temperature). In this case, the switching temperature or the glass transition or melting temperature of the at least one - originally unprogrammed - shape memory polymer of the first layer should preferably correspond at most to that of the at least one programmed shape memory polymer of the second layer, so that the latter is also heated to its glass transition or melting temperature range for its programming when the at least one shape memory polymer of the second layer is heated at least to the range of its glass transition or melting temperature for triggering its shape memory effect.

• - eine Lage aus wenigstens einem, insbesondere thermoplastischen, Polymer ohne Formgedächtniseigenschaften, vorzugsweise aus der Gruppe der Elastomere,
• - eine Lage aus wenigstens einem, insbesondere thermoplastischen, Polymer mit Formgedächtniseigenschaften, welches nicht programmiert ist, aber beispielsweise seinerseits durch Auslösen des Formgedächtniseffektes des wenigstens einen Formgedächtnispolymers der zweiten Lage seinerseits programmierbar sein kann, oder
• - eine Lage aus wenigstens einem Textilmaterial

aufweist.In the case of a layered composite material, according to a first embodiment variant, it can therefore be provided that only the at least one second layer has at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, wherein the at least one first layer in particular

• - a layer of at least one, in particular thermoplastic, polymer without shape memory properties, preferably from the group of elastomers,
• - a layer made of at least one, in particular thermoplastic, polymer with shape memory properties, which is not programmed, but can be programmable, for example, by triggering the shape memory effect of the at least one shape memory polymer of the second layer, or
• - a layer of at least one textile material

having.

Instead, according to a second method variant, it can be provided that only the at least one first layer consists of at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties is produced by depositing it in a first, e.g. essentially planar, shape, in particular by means of melt layers, preferably using at least one 3D printer, and programming it into at least one second shape. In this way, only the first layer - whether it is designed with an essentially constant or varying thickness - is given a shape recovery capacity, which the second layer can counteract to varying degrees depending on the material, thickness and complete or only partial presence, in order in turn to ensure primarily partial or practically complete shape changes of the layered composite material of varying extent.

• - eine Lage aus wenigstens einem thermoplastischen Polymer ohne Formgedächtniseigenschaften, insbesondere aus der Gruppe der thermoplastischen Elastomere, oder
• - eine Lage aus wenigstens einem thermoplastischen Polymer mit Formgedächtniseigenschaften, welches nicht programmiert wird, aber gegebenenfalls anlässlich der Formrückstellung der ersten Lage seinerseits in eine weitere Form programmiert werden kann, sofern seine Schalttemperatur höchstens jener des programmierten Formgedächtnispolymers der ersten Lage entspricht,

mittels Schmelzschichten auf der wenigstens einen ersten Lage abgeschieden werden, wobei die zweite Lage in jedem Fall eine hinreichende - plastische oder elastische - Verformbarkeit aufweisen sollte, um anlässlich der Formrückstellung der ersten Lage zumindest teil- bzw. bereichsweise (mit) verformt zu werden.In this case, at least a second layer can be

• - a layer of at least one thermoplastic polymer without shape memory properties, in particular from the group of thermoplastic elastomers, or
• - a layer made of at least one thermoplastic polymer with shape memory properties, which is not programmed but can optionally be programmed into a further shape when the first layer returns to its shape, provided that its switching temperature corresponds at most to that of the programmed shape memory polymer of the first layer,

by means of melt layers on the at least one first layer, wherein the second layer should in any case have sufficient - plastic or elastic - deformability in order to be at least partially or regionally (co-)deformed when the first layer recovers its shape.

• - eine Lage aus wenigstens einem thermoplastischen Polymer ohne Formgedächtniseigenschaften, insbesondere aus der Gruppe der thermoplastischen Elastomere, oder
• - eine Lage aus wenigstens einem thermoplastischen Polymer mit Formgedächtniseigenschaften, welches nicht programmiert ist, aber beispielsweise seinerseits durch Auslösen des Formgedächtniseffektes des wenigstens einen Formgedächtnispolymers der ersten Lage seinerseits programmierbar sein kann,

aufweist. Auf diese Weise wird nur der ersten Lage - sei sie mit im Wesentlichen konstanter oder veränderlicher Dicke ausgestaltet - ein Formrückstellungsvermögen verliehen, welchem die zweite Lage je nach Material, Dicke sowie vollständigem oder nur bereichsweisem Vorhandensein in unterschiedlichem Maße entgegenwirken kann, um wiederum vornehmlich bereichsweise oder praktisch gänzliche Formveränderungen des lagenförmigen Verbundmaterials unterschiedlichen Ausmaßes zu gewährleisten.In a layered composite material, according to a second embodiment, it can be provided that only the at least one first layer has at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, wherein the at least one second layer in particular

• - a layer of at least one thermoplastic polymer without shape memory properties, in particular from the group of thermoplastic elastomers, or
• - a layer of at least one thermoplastic polymer with shape memory properties, which is not programmed, but can be programmable, for example, by triggering the shape memory effect of the at least one shape memory polymer of the first layer,

In this way, only the first layer - whether it is designed with a substantially constant or variable thickness - is given a shape recovery capacity, which the second layer can counteract to varying degrees depending on the material, thickness and complete or only partial presence, in order in turn to ensure primarily partial or practically complete shape changes of the layered composite material of varying extent.

• - die wenigstens eine erste Lage aus wenigstens einem programmierten thermoplastischen Polymer mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften erzeugt wird, indem sie insbesondere mittels Schmelzschichten in einer ersten, z.B. im Wesentlichen planaren, Form abgeschieden und in wenigstens eine zweite Form programmiert wird, wonach
• - die wenigstens eine zweite Lage aus wenigstens einem programmierten thermoplastischen Polymer mit thermoresponsiven und/oder wasserresponsiven Formgedächtniseigenschaften erzeugt wird, indem sie mittels Schmelzschichten in einer, z.B. wiederum im Wesentlichen planaren, ersten Form auf der wenigstens einen ersten Lage abgeschieden und in wenigstens eine zweite Form programmiert wird,

wobei es sich bei den Formgedächtnispolymeren der ersten und zweiten Lage um dieselben oder um verschiedene Formgedächtnispolymere handeln kann. Auf diese Weise werden sowohl der ersten Lage - sei sie mit im Wesentlichen konstanter oder unterschiedlicher Dicke ausgestaltet - als auch der zweiten Lage - sei sie nur bereichsweise oder im Wesentlichen vollflächig auf die erste Lage aufgebracht und/oder sei sie mit im Wesentlichen konstanter oder unterschiedlicher Dicke ausgestaltet - ein Formrückstellungsvermögen verliehen, wobei sich die Formrückstellungen der Lagen zumindest bereichsweise verstärken und/oder zumindest bereichsweise hemmen können, um wiederum vornehmlich bereichsweise oder praktisch gänzliche Formveränderungen des lagenförmigen Verbundmaterials unterschiedlichen Ausmaßes zu gewährleisten.In addition, according to a third variant of the procedure, it can be provided that

• - the at least one first layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it in a first, e.g. substantially planar, shape in particular by means of melt layers and programming it into at least one second shape, after which
• - the at least one second layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it on the at least one first layer by means of melt layers in a, e.g. again substantially planar, first shape and programming it into at least one second shape,

wherein the shape memory polymers of the first and second layers can be the same or different shape memory polymers. In this way, both the first layer - whether it is designed with a substantially constant or different thickness - and the second layer - whether it is applied to the first layer only in certain areas or essentially over the entire surface and/or whether it is designed with a substantially constant or different thickness - are given a shape recovery capacity, wherein the shape recovery of the layers can be increased at least in certain areas and/or at least inhibited in certain areas, in order to ensure primarily regional or practically complete shape changes of the layered composite material of different extents.

In the case of a layered composite material, according to a third embodiment, it can be provided that both the at least a first layer and the at least one second layer each comprise at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties.

Furthermore, in the method according to the invention it is fundamentally conceivable that the at least one first layer is tensioned by means of melt layers during the deposition of the at least one second layer, depending on the material and flexibility, as is known as such in the production of so-called 4D textiles described at the beginning, in order to ensure an additional shape recovery effect of the layered composite material. Furthermore, the at least one first layer can also be unwound from a roll in the form of an endless layer, for example in the manner of the "roll-to-roll process" which is also known as such, and after the deposition of the at least one second layer it is wound up in particular on another roll, for example to produce very large-area layered composite materials with shape recovery properties.

• - der elektromagnetische Strahlung absorbierenden Füllstoffe,
• - der induktiv erwärmbaren Füllstoffe,
• - der Farbstoffe und Pigmente, und
• - der Verstärkungsfasern,

zugesetzt wird.
So kann beispielsweise durch die Verwendung von wärmeleitenden Füllstoffen, wie z.B. Graphit, Graphen, Ruß, Carbonfasern oder -pulvern und dergleichen, eine Verkürzung der Schaltzeiten erzielt werden, wenn die (jeweilige) Lage(n) des lagenförmigen Verbundmaterials aus einer herstellungstechnisch verliehenen ersten Form in die zweite Form überführt werden soll(en). Durch den Einsatz entsprechender Füllstoffe einschließlich draht- bzw. leiterbahnförmiger Elemente kann die hiermit versetzte Polymermatrix der (jeweiligen) Lage(n) des lagenförmigen Verbundmaterials ferner dahingehend funktionalisiert werden, dass sie unter Einfluss von äußeren Einwirkungen, wie elektrischem Strom, Magnetfeldern oder elektromagnetischer Strahlung, z.B. im Infrarot-, Ultraviolett- oder Mikrowellenspektrum, Wärme zu erzeugen vermag, sofern die z.B. metallischen oder Kohlenstoff-basierten Füllstoffe induktive bzw. strahlungsabsorbierende Eigenschaften besitzen. Vorteilhafte Füllstoffe können folglich beispielsweise eine Graphenstruktur aufweisen, wie sie z.B. im Graphit, in Kohlenstoffnanoröhrchen (carbon nano tubes, CNT), Graphen-Flocken oder expandiertem Graphit vorliegt. Ebenso können andere (Fein)partikel oder auch draht- bzw. leiterbahnförmige Elemente als Hilfsmaterialien bzw. Füllstoffe verwendet werden. Beispielsweise kommen hierfür magnetische bzw. ferromagnetische Partikel oder Drähte, z.B. aus Nickel-/Zinklegierungen, Eisenoxid und/oder Magnetit, in Betracht. Ebenfalls können sogenannte Nanoclays als Füllstoffe verwendet werden. Die Nanoclays können beispielsweise auf Basis von Siliciumnitrid, Siliciumcarbid, Siliciumoxid, Zirkonoxid und/oder Aluminiumoxid gebildet sein. Andere mögliche Füllstoffe umfassen oligomere Silsesquioxane, Graphit-Partikel, Graphene, Kohlenstoffnanoröhrchen, aber auch Metall-Feinpartikel oder -drähte. Selbstverständlich können auch Kombinationen solcher Füllmaterialien verwendet werden. Die Füllstoffe können ferner geeignet sein, um die mechanischen, elektrischen, magnetischen und/oder optischen Eigenschaften des Polymers einzustellen und an den jeweiligen Anwendungszweck anzupassen, wobei sie insbesondere im Wesentlichen gleichmäßig in einer (jeweiligen) Lage verteilt oder auch nur lokal akkumuliert sein können, um bei Exposition von elektromagnetischer Strahlung, Magnetfeldern oder dergleichen nur in diskreten Bereichen des lagenförmigen Verbundmaterials Wärme zu erzeugen und das wenigstens eine Formgedächtnispolymere hierbei gezielt nur in lokalen Bereichen des lagenförmigen Verbundmaterials auf die Schalttemperatur zu erwärmen, um nur lokale Formrückstellungen bewirken zu können. Darüber hinaus können selbstverständlich auch in der Polymertechnik übliche Additive zum Einsatz gelangen, wie z.B. Gleitmittel, Weichmacher, Antioxidantien, UV-Stabilisatoren, Mattierungsmittel, Verstärkungsstoffe, Flammschutzmittel, Antistatika, Hydrolysestabilisatoren, Schlagzähmodifikatoren und dergleichen.According to an advantageous development, it can further be provided that at least one additive, in particular from the group

• - the electromagnetic radiation absorbing fillers,
• - the inductively heatable fillers,
• - dyes and pigments, and
• - the reinforcing fibres,

is added.
For example, the use of thermally conductive fillers such as graphite, graphene, carbon black, carbon fibers or powders and the like can be used to shorten the switching times when the (respective) layer(s) of the layered composite material is to be converted from a first form given by manufacturing technology into the second form. By using appropriate fillers, including wire or conductor track-shaped elements, the polymer matrix of the (respective) layer(s) of the layered composite material mixed with them can also be functionalized in such a way that it is able to generate heat under the influence of external influences such as electric current, magnetic fields or electromagnetic radiation, e.g. in the infrared, ultraviolet or microwave spectrum, provided that the e.g. metallic or carbon-based fillers have inductive or radiation-absorbing properties. Advantageous fillers can therefore, for example, have a graphene structure, such as that found in graphite, carbon nanotubes (CNT), graphene flakes or expanded graphite. Other (fine) particles or wire- or conductor-shaped elements can also be used as auxiliary materials or fillers. For example, magnetic or ferromagnetic particles or wires, e.g. made of nickel/zinc alloys, iron oxide and/or magnetite, can be considered for this purpose. So-called nanoclays can also be used as fillers. The nanoclays can, for example, be based on silicon nitride, silicon carbide, silicon oxide, zirconium oxide and/or aluminum oxide. Other possible fillers include oligomeric silsesquioxanes, graphite particles, graphene, carbon nanotubes, but also metal fine particles or wires. Combinations of such fillers can of course also be used. The fillers can also be suitable for adjusting the mechanical, electrical, magnetic and/or optical properties of the polymer and adapting them to the respective application, whereby they can in particular be distributed substantially evenly in a (respective) layer or can also be accumulated only locally in order to generate heat only in discrete areas of the layered composite material when exposed to electromagnetic radiation, magnetic fields or the like and to heat the at least one shape memory polymer to the switching temperature only in local areas of the layered composite material in order to be able to bring about only local shape recovery. In addition, additives customary in polymer technology can of course also be used, such as lubricants, plasticizers, antioxidants, UV stabilizers, matting agents, reinforcing agents, flame retardants, antistatic agents, hydrolysis stabilizers, impact modifiers and the like.

• - der elektromagnetische Strahlung absorbierenden Füllstoffe,
• - der induktiv erwärmbaren Füllstoffe,
• - der Farbstoffe und Pigmente, und
• - der Verstärkungsfasern,

zugesetzt ist.In the layered composite material according to the invention, it can therefore also be provided that at least one additive, in particular from the group

• - the electromagnetic radiation absorbing fillers,
• - the inductively heatable fillers,
• - dyes and pigments, and
• - the reinforcing fibres,

is added.

• - smarte technische Bauteile, wie z.B. formveränderliche Schalter, Sensoren oder Aktoren für praktisch beliebige technische Einsatzgebiete;
• - formveränderliche Membrane in fluidischen Systemen verschiedener Anwendungsgebiete einschließlich der Medizintechnik;
• - formangepasste Hilfsmittel für den direkten Patientenkontakt in der Medizin einschließlich Prothesen, Orthesen und dergleichen;
• - Getriebe- und Zahnrädern mit inhärentem Überhitzungsschutz oder andere technische Bauteile mit programmiertem Materialverhalten, wie sogenannte „Shape-Changing Surfaces“ zur Anwendung in der Robotik, in der Aerodynamik oder dergleichen;
• - Dichtungen und Verbindungselemente, welche z.B. bei Temperaturerhöhung auf die Schalttemperatur infolge Formveränderung zu einer erhöhten Abdichtung/Wärmedämmung führen;
• - selbstfaltende und/oder selbstaufrichtende Strukturen, z.B. zur Anwendung in der Luft- und Raumfahrt, in der Schifffahrt, in der Biomedizin oder dergleichen;
• - selbstmontierende und/oder selbstreparierende Systeme, z.B. für das Bauwesen, für den Einsatz in unwirtlichen Umgebungen oder dergleichen,
• - selbstdemontierende Objekten, welche z.B. Verankerungselemente aufweisen, die sich zumindest teilweise zusammenziehen, sobald der Formgedächtniseffekt ausgelöst wird;
• - Mikrobauteile jedweder Art;
• - multifunktionale Objekte, z.B. zur Anwendung in der Biomedizin, in der Robotik oder dergleichen.
• - formändernde Schalter, Sensoren oder Aktuatoren für praktisch beliebige technische Einsatzgebiete; etc.

The layered composite material according to the invention can also be used in a variety of technical applications, for example to give objects actuator and/or sensor properties. The following are purely exemplary examples of other technical applications:

• - smart technical components, such as shape-changing switches, sensors or actuators for virtually any technical application;
• - shape-changing membranes in fluidic systems in various application areas including medical technology;
• - form-fitting aids for direct patient contact in medicine, including prostheses, orthoses and the like;
• - Gears and gear wheels with inherent overheating protection or other technical components with programmed material behavior, such as so-called “shape-changing surfaces” for use in robotics, aerodynamics or the like;
• - Seals and connecting elements which, for example, lead to increased sealing/thermal insulation due to a change in shape when the temperature rises to the switching temperature;
• - self-folding and/or self-erecting structures, e.g. for use in aerospace, marine, biomedical or similar applications;
• - self-assembling and/or self-repairing systems, e.g. for construction, for use in inhospitable environments or the like,
• - self-dismantling objects, which, for example, have anchoring elements that at least partially contract as soon as the shape memory effect is triggered;
• - Microcomponents of any kind;
• - multifunctional objects, e.g. for use in biomedicine, robotics or the like.
• - shape-changing switches, sensors or actuators for practically any technical application; etc.

• 1A eine fotografische Ansicht einer als erste Lage eines ersten Ausführungsbeispiels eines lagenförmigen Verbundmaterials verwendeten Folie aus einem thermoplastischen Polymer ohne Formgedächtniseigenschaften in Form eines thermoplastischen Polyurethanelastomers (TPU);
• 1B eine fotografische Ansicht der ersten Ausführungsform des lagenförmigen Verbundmaterials, nachdem auf die erste Lage gemäß 1A bereichsweise eine zweite Lage aus einem thermoplastischen Formgedächtnispolymer in Form eines Polyester-Polyurethans aufgebracht worden ist, wobei sich die zweite Lage in ihrer ersten Form befindet und in eine zweite Form programmiert worden ist;
• 1C fotografische Ansichten des lagenförmigen Verbundmaterials gemäß 1B, nachdem das Formgedächtnispolymer der zweiten Lage durch Auslösen des Formgedächtniseffektes in seine zweite Form geschaltet worden ist;
• 2A eine fotografische Ansicht einer als erste Lage eines zweiten Ausführungsbeispiels eines lagenförmigen Verbundmaterials verwendeten Folie aus einem thermoplastischen Polymer ohne Formgedächtniseigenschaften in Form eines thermoplastischen Polyurethanelastomers (TPU);
• 2B eine fotografische Ansicht der zweiten Ausführungsform des lagenförmigen Verbundmaterials, nachdem auf die erste Lage gemäß 2A bereichsweise eine zweite Lage aus einem thermoplastischen Formgedächtnispolymer in Form eines Polyester-Polyurethans aufgebracht worden ist, wobei sich die zweite Lage in ihrer ersten Form befindet und in eine zweite Form programmiert worden ist;
• 2C fotografische Ansichten des lagenförmigen Verbundmaterials gemäß 2B, nachdem das Formgedächtnispolymer der zweiten Lage durch Auslösen des Formgedächtniseffektes in seine zweite Form geschaltet worden ist;
• 3A fotografische Ansichten eines dritten Ausführungsbeispiels eines lagenförmigen Verbundmaterials mit einer ersten Lage aus einem thermoplastischen Formgedächtnispolymer in Form eines Polyester-Polyurethans und einer zweiten Lage aus einem thermoplastischen Formgedächtnispolymer in Form eines Polyester-Polyurethans, wobei die zweite Lage bereichsweise auf die erste Lage aufgebracht und sich die Formgedächtnispolymere beider Lagen in ihrer ersten Form befinden und in je eine zweite Form programmiert worden sind; und
• 3B fotografische Ansichten des lagenförmigen Verbundmaterials gemäß 3A, nachdem die Formgedächtnispolymere der ersten und zweiten Lage durch Auslösen des Formgedächtniseffektes in ihre zweite Form geschaltet worden sind.

Further features and advantages of the invention will become apparent from the following description of embodiments with reference to the drawings, in which:

• 1A a photographic view of a film made of a thermoplastic polymer without shape memory properties in the form of a thermoplastic polyurethane elastomer (TPU) used as the first layer of a first embodiment of a layered composite material;
• 1B a photographic view of the first embodiment of the layered composite material after the first layer according to 1A a second layer of a thermoplastic shape memory polymer in the form of a polyester-polyurethane has been applied in regions, the second layer being in its first shape and having been programmed into a second shape;
• 1C Photographic views of the layered composite material according to 1B after the shape memory polymer of the second layer has been switched into its second shape by triggering the shape memory effect;
• 2A a photographic view of a film made of a thermoplastic polymer without shape memory properties in the form of a thermoplastic polyurethane elastomer (TPU) used as the first layer of a second embodiment of a layered composite material;
• 2 B a photographic view of the second embodiment of the layered composite material after the first layer according to 2A a second layer of a thermoplastic shape memory polymer in the form of a polyester-polyurethane has been applied in regions, the second layer being in its first shape and having been programmed into a second shape;
• 2C Photographic views of the layered composite material according to 2 B after the shape memory polymer of the second layer has been switched into its second shape by triggering the shape memory effect;
• 3A photographic views of a third embodiment of a layered composite material with a first layer made of a thermoplastic shape memory polymer in the form of a polyester-polyurethane and a second layer made of a thermoplastic shape memory polymer in the form of a polyester-polyurethane, the second layer being applied to the first layer in some areas and the shape memory polymers of both layers being in their first shape and each having been programmed into a second shape; and
• 3B Photographic views of the layered composite material according to 3A after the shape memory polymers of the first and second layers have been released by releasing the mold memory effect have been switched into their second form.

As from the 1A As can be seen, according to a first embodiment of a layered composite material according to the invention, a resilient, elastic, flat layer made of a thermoplastic polymer without shape memory properties in the form of a thermoplastic polyurethane elastomer (TPU) was provided. As can be seen from the 1B As can be seen, a second flat layer made of a thermoplastic shape memory polymer in the form of a polyester polyurethane was applied to the first layer in some areas - here: essentially in the form of two cross-shaped bands - by printing the first layer with the shape memory polymer of the second layer using a 3D printer. The second layer was thereby removed from its original 1B reproduced first form into a second form, as described in detail above. In the 1C The layered composite material is in accordance with 1B shown after the shape memory polymer of the second layer has been switched into its second shape by triggering the shape memory effect by heating it to a temperature above the switching or glass transition temperature of its soft segments. A drastic change in shape of the previously essentially flat structure into a three-dimensional surface structure can be seen, with the first layer also being deformed due to its material connection with the second layer.

The second embodiment according to the 2A to 2C differs from that of the 1A to 1C primarily by the shape of the flexible, elastic, flat first layer made of a thermoplastic polyurethane elastomer (TPU) without shape memory properties (see the 2A) printed second layer of a shape memory polymer in the form of a thermoplastic polyester-polyurethane, which in the present case comprises several essentially cross- and star-shaped bands (cf. the 2 B) . The 2C shows the layered composite material according to the 2 B after the shape memory polymer of the second layer has been switched into its second shape by triggering the shape memory effect by heating it to a temperature above the switching or glass transition temperature of its soft segments. Here, too, one can see a drastic change in shape of the previously essentially flat structure into a three-dimensional surface structure, with the first layer also being deformed due to its material connection with the second layer.

In the embodiment according to the 3A and 3B In deviation from the above examples, the 1 and 2 both layers were made of thermoplastic shape memory polymers in the form of polyester-polyurethanes, whereby the first flat layer was first printed using a 3D printer and programmed in the manner described above. A second flat layer made of a thermoplastic shape memory polymer in the form of a (the same or different) polyester-polyurethane was applied to the first layer in some areas - here: essentially in the form of four cross-shaped bands - by printing the first layer with the shape memory polymer of the second layer using a 3D printer. The second layer was also printed from its original shape during printing. 3A reproduced first form into a second form, as described in detail above. In the 3B The layered composite material is in accordance with 3A shown after the shape memory polymers of the first and second layers have been switched into their second shape by triggering the shape memory effect by heating them to a temperature above the switching or glass transition temperature of their soft segments. Here, too, one can see a drastic change in shape of the previously essentially flat structure into a three-dimensional surface structure, with the two layers being deformed together as a result of their material connection.

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was 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 accepts no liability for any errors or omissions.

Cited patent literature

• EN 1020221255832 [0009, 0016]
• DE 102019007939 A1 [0011]

Cited non-patent literature

• https://www.stylepark.com/de/news/techtextil-2019-4d-textilien, downloaded on 06.10.2022 [0002]
• N. Fritzsche, T. Pretsch in Macromolecules 47, 2014, 5952-5959; N. Mirtschin, T. Pretsch in RSC Advances 5, 2015, 46307-46315 [0009]
• T. Pretsch, M. Bothe: “Bidirectional actuation of a thermoplastic polyurethane elastomer”, Journal of Materials Chemistry A, 20 (2013), 14.491-14.497 [0010]

Claims (21)

Method for producing a layered composite material, comprising (a) at least one first, substantially planar layer that is deformable at least between a first shape and a second shape, and (b) at least one second, substantially planar layer that is deformable at least between a first shape and a second shape, made of at least one thermoplastic polymer, applied at least in regions to the first layer, wherein the at least one second layer is deposited at least in regions on the at least one first layer by means of melt layers, characterized in that at least one of the layers is produced by means of melt layers of at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, which on the one hand has - hard segments with at least one melt transition temperature range, on the other hand - soft segments and/or mixed phases of soft segments and hard segments with a glass transition or melting temperature range below the melt transition temperature range of the hard segments, wherein the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer during the melt layering to the at least one layer deposited in a first mold and programmed into at least one second mold such that the at least one layer is switched into the at least one second mold upon heating to the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer having thermoresponsive and/or water-responsive shape memory properties and/or upon contact with water. Procedure according to Claim 1 , characterized in that at least one thermoplastic polymer with shape memory properties of at least one of the layers is selected from the group of one-way or two-way shape memory polymers. Procedure according to Claim 1 or 2 , characterized in that at least the at least one second layer is deposited on the at least one second layer by means of melt layers using at least one 3D printer. Method according to one of the Claims 1 until 3 , characterized in that the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is programmed to its second shape during melt layering by - heating it during melt layering to a maximum temperature below the upper limit temperature of the melt transition temperature range of its hard segments, so that the hard segments are not completely melted, and/or - depositing it by means of a suitable movement profile of the print head of a 3D printer, after which the at least one layer is cooled to a temperature below the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties. Method according to one of the Claims 1 until 4 , characterized in that the programmed shape recovery capacity of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is adjusted by - the temperature set in a plasticizing unit and/or in an outlet nozzle of the 3D printer, and/or - the pressure set in a plasticizing unit and/or in an outlet nozzle of the 3D printer, and/or - the plasticized strands of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties are held at a temperature in or above the glass transition or melting temperature range of the soft segments during and/or after their discharge from the at least one print head of the 3D printer and are deformed by controlling the direction and/or the amount of the relative speed of the print head in relation to a print table of the 3D printer. Method according to one of the Claims 1 until 5 , characterized in that the at least one second layer is deposited - only in regions, in particular in the form of geometric structures, or - substantially over the entire surface of the at least one first layer. Method according to one of the Claims 1 until 6 , characterized in that only the at least one second layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it on the at least one first layer by means of melt layers in a first mold and programmed into at least a second form. Procedure according to Claim 7 , characterized in that as at least one first layer - a layer made of at least one, in particular thermoplastic, polymer without shape memory properties, in particular from the group of elastomers, or - a layer made of at least one textile material is used. Procedure according to Claim 7 , characterized in that as at least one first layer a layer of at least one, in particular thermoplastic, polymer with shape memory properties is used, which is not programmed, but is in turn programmable into a further shape, in particular on the occasion of the shape recovery of the second layer. Method according to one of the Claims 1 until 6 , characterized in that only the at least one first layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it in a first shape, in particular by means of melt layers, preferably using at least one 3D printer, and programming it into at least one second shape. Procedure according to Claim 10 , characterized in that as at least one second layer, - a layer made of at least one thermoplastic polymer without shape memory properties, in particular from the group of thermoplastic elastomers, or - a layer made of at least one thermoplastic polymer with shape memory properties, which is not programmed, is deposited on the at least one first layer by means of melt layers. Method according to one of the Claims 1 until 6 , characterized in that - the at least one first layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, in particular by depositing it in a first shape by means of melt layers and programming it into at least one second shape, after which - the at least one second layer is produced from at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties by depositing it in a first shape on the at least one first layer by means of melt layers and programming it into at least one second shape. Method according to one of the Claims 1 until 12 , characterized in that the at least one first layer is - tensioned by means of melt layers during the deposition of the at least one second layer and/or - is unwound from a roll in the form of an endless layer, wherein after the deposition of the at least one second layer it is wound up in particular on a further roll. Method according to one of the Claims 1 until 13 , characterized in that at least one additive, in particular from the group - of fillers absorbing electromagnetic radiation, - of inductively heatable fillers, - of dyes and pigments, and - of reinforcing fibers, is added to the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of at least one of the layers, at least in local regions of the layer. A layered composite material which is produced by a process according to any of the Claims 1 until 14 can be produced, comprising (a) at least one first, substantially planar layer that is deformable at least between a first shape and a second shape, and (b) at least one second, substantially planar layer that is deformable at least between a first shape and a second shape, made of at least one thermoplastic polymer, applied at least in regions to the first layer, wherein the at least one second layer is applied at least in regions to the at least one first layer, characterized in that at least one of the layers has at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, which on the one hand has - hard segments with at least one melting transition temperature range, on the other hand - soft segments and/or mixed phases of soft segments and hard segments with a glass transition or melting temperature range below the melting transition temperature range of the hard segments, wherein the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of the at least one layer is present in a first shape and is programmed into at least one second shape in such a way that the at least one layer when heated to the glass transition or melting temperature range of the soft segments of the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties and/or upon contact with water is switched into the at least one second shape. Layered composite material according to Claim 15 , characterized in that the at least one thermoplastic polymer with shape memory properties of the at least one layer is a one-way or a two-way shape memory polymer Layered composite material according to Claim 15 or 16 , characterized in that the at least one second layer is applied - only in regions, in particular in the form of geometric structures, or - substantially over the entire surface of the at least one first layer. Layered composite material according to one of the Claims 15 until 17 , characterized in that only the at least one second layer has at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, wherein the at least one first layer in particular - a layer made of at least one, in particular thermoplastic, polymer without shape memory properties, in particular from the group of elastomers, - a layer made of at least one, in particular thermoplastic, polymer with shape memory properties which is not programmed, or - a layer made of at least one textile material. Layered composite material according to one of the Claims 15 until 17 , characterized in that only the at least one first layer has at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties, wherein the at least one second layer in particular - has a layer made of at least one thermoplastic polymer without shape memory properties, in particular from the group of thermoplastic elastomers, or - a layer made of at least one thermoplastic polymer with shape memory properties which is not programmed. Layered composite material according to one of the Claims 15 until 17 , characterized in that both the at least one first layer and the at least one second layer each comprise at least one programmed thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties. Layered composite material according to one of the Claims 15 until 20 , characterized in that at least one additive, in particular from the group - of fillers which absorb electromagnetic radiation, - of fillers which can be heated inductively, - of dyes and pigments, and - of reinforcing fibres, is added to the at least one thermoplastic polymer with thermoresponsive and/or water-responsive shape memory properties of at least one of the layers, at least in local regions of the layer.