Coated shape-memory polymer fibers for textile applications

Abstract

The present invention relates to the field of fibers, and in particular to a shape memory polymer fiber (SMPF) for textile or medical applications, which can maintain constant shape fixity and recovery even after multiple shape memory cycles. The present invention relates to a coated shape memory polymer fiber (cSMPF) (1) having a core fiber (10) containing a shape memory polymer fiber and a substantially inelastic covering yarn (20), wherein the covering yarn (20) is wound around the core fiber (10), and the maximum engineering strain (ε) of the core shape memory fiber is controlled. max ) is the yield strain (ε yield ) or less, thereby limiting the stretch or deformation of the textile and / or fabric comprising the core shape memory fiber and / or the coated shape memory fiber during programming or use, ensuring maximum recovery strain. Also disclosed are coated shape memory polymer fibers (cSMPF) (1), shape memory fibers, and methods of making shape memory textiles comprising coated shape memory polymer fibers (cSMPF).

Description

Technical Field

[0001] The present invention belongs to the field of shape memory fibers, and relates to coated shape memory polymer fibers, a method for manufacturing the same, and a shape memory fabric and a shape memory textile including the same. The present invention relates to the textile field, particularly to shape memory polymer fibers, and has been partially developed under the EU project "GrowBot - Towards a new generation of evolving artifacts inspired by plants" (grant contract number 824074).

Background Art

[0002] Shape memory polymers (SMPs) are emerging smart materials that can change their size and shape in response to external stimuli such as heat, electric current, electromagnetic fields, water, light, etc. A typical SMP has the ability to remember its original shape even after deformation such as elongation. An SMP maintains its deformed state without stimulation and returns to its original shape when an external stimulus is applied. Research on SMPs for biomedical applications is becoming increasingly active. From a structural perspective, SMPs can be classified into three-dimensional systems such as shape memory blocks or shape memory foams, two-dimensional systems such as shape memory films, and one-dimensional systems such as shape memory fibers, and shape memory fibers have attracted the most attention. Shape memory fibers in woven fabrics, non-woven fabrics, and knitted fabrics can be converted into two-dimensional systems and / or three-dimensional systems.

[0003] Fibrous SMPs have attracted great interest in structural and functional applications due to their flexibility, anisotropy, and the ability to transform into two-dimensional and / or three-dimensional systems. Known shape memory fibers are produced by electrospinning from polyurethane block copolymers or multi-block copolymers containing poly(ω-pentadecalactone) hard segments (PPDL) and poly(ε-caprolactone) switching segments (PCL), as disclosed in F. Zhang et al., "Shape Memory Polymer Nanofibers and Their Composites: Electrospinning, Structure, Properties, and Applications," Frontiers in Materials, October 2015, Vol. 2, Article 62, or by extrusion from poly(ethylene-co-vinyl acetate) random copolymers, as disclosed in K. Wang et al., "Thermal and Mechanical Properties of Poly(ethylene-co-vinyl acetate) Random Copolymer (PEVA) and Its Covalently Crosslinked Analogue (cPEVA)," Polymers 2019, 11, 1055 (2019).

[0004] Chinese Patent Application CN1706997A discloses shape memory fibers made from shape memory polyurethane and its manufacturing method, and Chinese Utility Model CN201553838U discloses thermosensitive shape memory polyurethane coated yarns (shape memory polymer fibers, cSMPF) and its manufacturing method. Also, in Chinese Utility Model Application CN201545991U related to this disclosure, the central shape memory yarn is coated by an outer winding yarn coated on the surface of the central yarn, featuring a soft touch and anti-wrinkle effect.

[0005] The cSMPF can be programmed by stretching at various temperatures before or after coating with conventional yarns in the textile industry such as cotton, nylon, and polyester. Compared with the coated yarn structures of other fibers, the thermosensitive shape memory polyurethane disclosed here has better elasticity, a stronger fabric anti-wrinkle ability, and easily recovers to its original permanent shape.

[0006] This coating may be necessary not only to overcome technical constraints related to processing, but also for comfort and to comply with regulatory requirements that such fibers must be avoided in direct contact with the wearer's body. The heat-sensitive shape-memory polyurethane disclosed in CN201553838U is described as having improved wrinkle resistance and elasticity compared to coated yarn structures of other fibers. The diameter ratio of the coated yarn to the core yarn is reported to be in the range of 0.1 to 1.0.

[0007] WO2012 / 045427A1 discloses medical aids, particularly body support bandages and orthoses, comprising or consisting of a shape memory material, which include at least one element that generates or provides support, compression or pressure introduction. The programmed shape memory transition of the medical aid is triggered by body temperature, thereby changing the elongated shape of the medical aid, which facilitates attachment to the body, to a contracted shape that conveys the support and / or compression effect of the medical aid. The shape memory material relating to this disclosure is a composite material, mixture, alloy, or composite material having different shape memory effects.

[0008] In addition to the related fields of development and application of shape memory polymers, there are several known disclosures regarding the manufacture and use of coated fibers. These coated fibers have improved properties compared to uncoated fibers.

[0009] For example, WO2000038531A1 discloses a tubular packaging for food use having a circumferential thread containing an elastic thread having a predetermined elastic limit, below which the thread is elastically stretchable, and at which which the thread is not stretchable. This example from the food industry suggests that a thread having a predetermined elastic limit can be used to limit the expansion of the covering of a tubular thread used in food.

[0010] An example relating to the elastic limit or breaking point of elastic rubber is described in US1679822A. This describes multiple short, low-tension coated elastic rubber yarns wound in a spiral with different layers of coating. These multiple different layers are used to significantly reduce the stretchability below the elastic limit and tensile point of the fibers contained therein.

[0011] WO2004027132A1 relating to conductive elastic yarn discloses an example of an elastic core covered with multiple yarns, of which at least one yarn is intended to limit the stretchability of the cured fiber. The object of this application is to provide a wire alternative for textile applications that is more flexible, thinner, and stretchable, and therefore loom-processable.

[0012] In the textile industry, there remains a demand for products with shape-memory properties, particularly useful for medical applications. Specifically, there is a continued need for shape-memory polymer fibers (SMPFs) that can maintain consistent shape retention and recovery over multiple shape-memory cycles, for textile and / or medical applications.

[0013] To date, no method or product is known that specifically produces a reproducible shape memory effect with high shape retention and shape recovery rates caused by excessive stretching of the fibers involved. This is particularly important for fibers, fabrics, and textiles that possess such a distinct shape memory effect. [Overview of the project] [Problems that the invention aims to solve]

[0014] The objective of this invention is to address and overcome the major drawbacks in the field of shape memory fibers found in the prior art. Conventional shape memory polymer fibers (SMPFs), while exhibiting excellent shape memory properties, have the limitation of being easily stretched beyond the recoverable shape memory programming range. This limitation often results in the loss of shape memory function, reducing the effectiveness of the fiber and rendering it unusable for its intended application, particularly reducing important properties such as shape recovery rate and shape recovery retention. When a fiber is stretched beyond a certain point, its ability to return to its pre-programmed shape is impaired. This drawback not only shortens the functional life of these materials but also limits their usability in applications where the fiber may be subjected to various strains. Such situations are common in fields such as medicine, orthopedics, leisure, sports, and other dynamic environments where adaptability and durability are important.

[0015] Therefore, the object of the present invention is to develop shape memory polymer fibers (SMPFs), particularly coated shape memory polymer fibers, that maintain their shape memory ability even under conditions of strain exceeding the conventional application limits, i.e., the strain at the yield point of uncoated core fibers. By improving the overstretch strength of these fibers, the present invention aims to expand the functional range and durability of shape memory materials and to make them suitable for a wider range of practical applications than those previously limited by the mechanical degradation of the shape memory properties of conventional fibers. [Means for solving the problem]

[0016] This problem is solved by a coated shape memory polymer fiber (cSMPF) having the features of claim 1. The present invention further discloses a method for producing the same, a shape memory textile containing the same, a shape memory fabric containing the same, and uses thereof.

[0017] Further advantageous embodiments and further developments are shown in the specification with reference to the dependent claims and drawings. [Effects of the Invention]

[0018] The coated shape memory polymer fiber of the present invention solves mechanical problems associated with the shape memory effect of conventional shape memory fibers, such as shape recovery rate, encountered in functional clothing and garments used in practical textile applications, particularly in medical, recreational, and technical applications, by coating the shape memory polymer of the core fiber with a substantially non-stretchable coating yarn such that the maximum engineering strain of the core fiber is reduced to below the strain at the yield point of the uncoated core fiber.

[0019] This allows shape-memory materials to be applied to textiles and fabrics that need to be processed into clothing that may be used in medical, leisure, and technical applications. One of the main advantages of the cSMPF of this disclosure is that it can maintain consistent shape retention and recovery over multiple shape-memory cycles. This is extremely important in medical applications where accuracy and reliability are required.

[0020] Furthermore, this design limits the maximum elongation of the core fibers to a predetermined strain, preventing overstretching and potential structural damage. This limitation is particularly advantageous in medical textiles where controlled compression and consistent support are essential for therapeutic effects, especially when constant and reproducible pressure is required for effective treatment.

[0021] The covering yarn not only limits the elasticity of the core fibers but also adds another protective layer. This additional layer helps protect the core fibers from environmental factors and mechanical abrasion, thereby improving the overall durability and lifespan of the fibers and the textile products manufactured from them. [Brief explanation of the drawing]

[0022] [Figure 1] Figure 1 shows a schematic diagram of a coated shape memory polymer fiber (cSMPF) according to the present invention. [Figure 2] Figure 2A shows a schematic diagram of the coated shape memory polymer fiber (cSMPF) according to the present invention in its non-extended state, and Figure 2B shows a schematic diagram of the coated shape memory polymer fiber (cSMPF) according to the present invention in its extended state. [Figure 3] Figure 3A shows a schematic diagram of an exemplary semi-crystalline shape memory polymer cured using radiation, a benzophenone initiator, and a trifunctional cross-linker (FG = functional group, e.g., an ethylene group), and Figure 3B shows a schematic diagram of the curing process from PEVA polymer to PEVA (covalently crosslinked PEVA) by the initiator and cross-linker, showing some of the possible covalent crosslinking sites according to the present invention. [Figure 4] Figure 4A shows an example of thermally programming a shape memory textile containing coated shape memory polymer fibers (cSMPF) in a laboratory environment, and Figure 4B shows an example of thermally programming a shape memory textile containing coated polymer shape memory fibers (cSMPF) onto a subject's body. [Modes for carrying out the invention]

[0023] <Coated shape memory polymer fibers (cSMPF)> The present invention relates to a coated shape memory polymer fiber (cSMPF) having a core fiber and a substantially non-stretchable coating yarn wound around the core fiber such that the maximum engineering strain of the core fiber is reduced to less than or equal to the strain at the yield point of the uncoated core fiber.

[0024] In the context of the present invention, "having" can be used synonymously or interchangeably with the terms "including" or "consisting of," meaning that a certain feature includes or consists of a particular secondary feature.

[0025] In a more preferred embodiment, the present invention includes at least, - A core fiber (10) containing or consisting of a shape memory polymer (SMP), - A substantially non-stretchable coated yarn (20), The present invention relates to a coated shape memory polymer fiber (cSMPF) (1) comprising or consisting of, wherein a substantially non-stretchable coated yarn (20) is wound around the core fiber (10) such that the maximum engineering strain of the core fiber (10) contained in the coated shape memory polymer fiber (1) is reduced to less than or equal to the strain at the yield point of the uncoated core fiber (10).

[0026] In a more preferred embodiment, the present invention includes at least - A core fiber (10) containing or consisting of a shape memory polymer, - A substantially non-stretchable covering yarn (20) wrapped around the core fiber (10), The coated shape memory polymer fiber (cSMPF) (1) comprises or comprises the maximum engineering strain (ε) of the core fiber (10) contained in the coated shape memory polymer fiber (1). max ) is preferably measured at 25°C, and is the yield strain (ε) of the uncoated core fiber (10). yield ) is limited to below, where the yield strain (ε yield The range is preferably 10% to 100%, more preferably 15% to 70%, and most preferably 20% to 60%. This has the advantage that cSMPF exhibits consistent shape stability and recovery over multiple shape memory cycles, ensuring a wide stretch range while maintaining shape memory properties. This is extremely important for a wide range of textile applications where accuracy and reliability are required.

[0027] In some preferred embodiments, the maximum engineering strain (ε) of the core fiber (10) contained in the coated shape memory polymer fiber (1) max ) is preferably measured at 25°C, and is the yield strain (ε) of the uncoated core fiber (10). yield ) is limited to below, where the yield strain (ε yield) is within a numerical range obtained by combining any two of the following endpoint values: 10%, 12%, 14%, 16%, 18%, 20%, 22%, 24%, 26%, 28%, 30%, 40%, 45%, 50%, 52%, 54%, 56%, 58%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, and 100%.

[0028] In the context of the present invention, the "core fiber (10)" (also referred to as the "core shape memory fiber (10)") comprises or consists of a shape memory polymer and may be coated by a substantially non - stretchable covering yarn (20) wound around the core fiber (10). In this context, the maximum engineering strain (ε max ) of the core fiber (10) is equivalent to the maximum engineering strain (ε max ) of the coated shape memory polymer fiber (cSMPF) including the core fiber (10).

[0029] In the context of the present invention, the "uncoated core fiber (10)" (sometimes also referred to as the "core fiber (10)") comprises or consists of a shape memory polymer that does not have a substantially non - stretchable covering yarn (20) wound around the core fiber (10). Therefore, the strain (ε yield ) at the yield point of the uncoated core fiber (10) is equivalent to the yield point of the core fiber (10) of the coated shape memory polymer fiber (cSMPF) that does not have a substantially non - stretchable covering yarn (20).

[0030] The "fiber" in the present invention is a single continuous thread of material, with one axial direction being much longer in shape than the other two relatively short directions.

[0031] In the present invention, "filament" may be either a monofilament corresponding to "fiber" in the spirit of the present invention, or a multifilament containing at least one "fiber" in the spirit of the present invention. A multifilament is a bundle of co-oriented fibers, and in a preferred embodiment, it may be a filament fiber, i.e., a fiber whose length is approximately the same as the length of the multifilament (common examples include ropes, cables, and synthetic fiber yarns), or in another preferred embodiment, it may be a short fiber, i.e., a fiber whose length is significantly shorter than the total length of the multifilament (common examples include cotton yarn and wool yarn).

[0032] In one aspect, the present invention relates to a core fiber of a semicrystalline polymer fiber and the maximum engineering strain (ε) of the core shape memory fiber. max ) yield strain (ε yield The present invention relates to a coated shape memory polymer fiber (cSMPF) having a substantially non-stretchable coating yarn wound around a core fiber such that the coating yarn is less than or equal to 1 / 2. Thus, the coating yarn is used to limit the stretchability or deformation of the core shape memory fiber during programming and to ensure maximum recovery strain. The maximum deformation by coating a core fiber of a given length (L0) and diameter (D0) with the coating yarn may be influenced by the entanglement density (preferably also called the coating density) (ρ0) of the core fiber in its unstretched state, i.e., the number of twists per meter of the coating yarn when the core fiber is in its unstretched state, as well as the length (l) and diameter (d) of the coating yarn, all of which relate to the diameter (D0) of the core fiber in its unstretched state.

[0033] When stress is applied to a coated fiber to stretch it, the length of the core fiber (L1) increases, but the entanglement density (ρ1) decreases. The strain of the core fiber (ε) is given by the following equation:

number

[0034] Since the deformation of the SMPF is limited to the yield point and / or elastic limit, "stress" and "strain" can be used interchangeably in this invention. Within this range, each strain value may correspond to a single stress value. This is why each point on the stress-strain curve of the SMPF can be clearly defined by either a stress value or a strain value.

[0035] When the core fiber wrapped with the covering yarn is stretched (extended), the pitch (r), i.e., the distance between two loops of the twisted covering yarn around the core fiber, increases from r0 to r1, and the entanglement density (ρ1) decreases. The covering yarn is at the maximum strain (ε) of the core fiber. max It does not stretch until it reaches ) the maximum strain (ε). max To stretch it beyond ε, the coated yarn also needs to be stretched. Assuming the coated yarn is substantially non-stretchable, the fiber is stretched to its maximum strain (ε max If stretched beyond this point, the force required for further stretching or deformation increases rapidly. Beyond this point, the force exerted by the coating yarn on the core fibers increases, potentially crushing and damaging the core fibers, and ultimately causing the coating yarn to break.

[0036] According to the present invention, the maximum strain (ε) of the core fiber max ) is the strain (ε) at the yield point of the core fiber. yield The selection should not exceed the maximum strain (ε). According to some embodiments, the maximum strain (ε) should be selected so as not to exceed this value. max ) is independent of the material of the covering yarn and depends only on the diameter (D0) of the core fiber (cSMPF) of the shape memory polymer, the diameter (d) of the covering yarn, and the entanglement density (ρ0), where the entanglement density (ρ0) is given by:

number

[0037] According to some preferred embodiments of the present invention, the yield strain of the core fiber (cSMPF) of the shape memory polymer depends on the material of the core fiber, particularly the shape memory polymer contained in the core fiber, and the diameter (D0) of the core fiber, and is limited by appropriately selecting the diameter (d) and entanglement density (ρ0) of the coating yarn, as well as the material of the coating yarn, but the maximum strain (ε) of the core fiber is determined by the material and diameter of the core fiber. max ) is the strain (ε) at the yield point of the core fiber. yield You need to choose a value that does not exceed ).

[0038] Maximum engineering strain (ε) of the core shape memory fibers max ) the yield strain (ε) of the uncoated core fibers yield The length of the covering yarn required to reduce the density below depends on the length of the core fiber and is given by the following formula:

number

[0039] The coated yarn can be coated with a twist in the S or Z direction and wound around the core fibers with a single or double twist. The twist density is preferably in the range of 750 to 3000 twists per meter.

[0040] The yield point is the point on the stress-strain curve that indicates the limit of elastic behavior. Therefore, the engineering strain (ε) at the yield point is... yield The yield point is the strain (extension) that the core fibers can withstand without permanent deformation. The yield point is a material property value that can be measured according to ISO 527.

[0041] In a particularly preferred embodiment of the present invention, the "yield point" corresponds to the "elastic limit," which is the point that indicates the limit of elastic behavior on the stress-strain curve. Most preferably, the engineering strain (ε) at the yield point isyield ) is limited to strain at the elastic limit. In particular, in the context of the shape memory polymer composed of the core fibers of the cSMPF of the present invention, the elastic limit is determined by a suitable indirect temperature measurement system, preferably an IR camera, e.g., ThermaCam TM This can be measured by thermomechanical analysis using a tensile testing machine equipped with Phoenix, such as the MTS 858 testing machine. An exemplary procedure is described in "Experimental and numerical investigation of yield phenomena in shape memory polymers subjected to periodic tension at various strain rates" (EAPieczyska, M.Staszczak, K.Kowalczyk-Gajewska, M.Maj, K.Golasinski, S.Golba, H.Tobushi, S.Hayashi, Polymer Testing, Vol. 60, 2017, pp. 333-342, ISSN 0142-9418, https: / / doi.org / 10.1016 / j.polymertesting.2017.04.014). The importance of distinguishing between the elastic deformation region and the plastic deformation region is crucial for understanding the behavior of materials under stress. The elastic region exhibits reversible deformation, while the plastic region exhibits permanent deformation. The yield point is closely related to the elastic limit and is an indicator of the transition from elastic to plastic behavior, representing the maximum strain that the SMP can withstand without permanent deformation. Therefore, the engineering strain (ε) max ) yield point (ε yield Limiting the deformation to the elastic limit is important to ensure a high shape recovery rate and the mechanical stability of the shape memory effect against strain.

[0042] The elastic limit is described in "Strain recovery and stress relaxation behavior of physically crosslinked multiblock copolymer blends by PLA stereocomplexing," Izraylit, V., Heuchel, M., Gould, OE, Kratz, K., and Lendlein, A, (2020), Polymer, 209, 122984, https: / / doi.org / 10.1016 / j.polymer.2020.122984, and can be determined by the performed step cycle test. Here, the elastic limit is determined by the step cycle test. The sample was stretched to a specific strain ε at a constant elongation rate. Then, the stress was removed to 0 at the same contraction rate. In each subsequent step, the sample was stretched to a higher strain than in the previous step. This cycle was continued until the sample fractured. The recovered strain is the elastic component ε of the deformation. e It is considered that the remainder is the plastic component of deformation ε p The elastic limit is ε p (σ) can be determined as the point where the tangent line to (σ) increases sharply, where σ is the ε at a particular step in the step cycle experiment. p This represents the stress value on the stress-strain curve at deformation ε. In this study, the yield point is defined as the point in the elastic limit region where the curvature of the stress-strain curve is maximum. In practical terms, it is preferable that the difference between these points can be ignored.

[0043] The expression "substantially instretchable" means that the coated yarn is stiffer than the core fibers. This ratio can be quantified by Young's modulus. Young's modulus is a mechanical property that measures the compressive stiffness, and in this context, particularly the tensile stiffness, of a solid material when a longitudinal force is applied to it. In one embodiment of the present invention, the coated yarn has a higher Young's modulus than the core fibers. In another embodiment of the present invention, the Young's modulus of the coated yarn is at least twice, preferably at least three times, and most preferably at least five times, the Young's modulus of the core fibers.

[0044] In another embodiment, the ratio of the core fiber diameter D0, the coating yarn diameter d, and the entanglement density ρ0 is such that during the elongation of the cSMPF, the elongation of the coating yarn 20 begins and the tangent slope of the stress-strain curve increases sharply ε onset It is defined such that there exists. Other parameters necessary to determine the ratio of D0, d and ρ0 are the length L of the core fiber, the length l of the covering yarn, the distance r between two loops of the twist, also called the pitch, and the number of twists n. L0 defines the length of the core fiber in its non-stretched state, and L1 defines the length of the core fiber 10 in its stretched state. D0 defines the diameter of the core fiber 10 in its non-stretched state, and D1 defines the diameter of the core fiber 10 in its stretched state. ΔL is the change in the length of the core fiber 10, where ΔL = L1 - L0. ΔD is the change in the diameter of the core fiber 10, where ΔD = D1 - D0.

[0045] The engineering strain ε of the core fiber 10 is as follows:

number

[0046] The Poisson's ratio ν of core fiber 10 is as follows:

number

[0047] The formula for Poisson's ratio ν of core fiber 10 is as follows:

number

[0048] From the above equation, the following relationship is expressed:

number

[0049] Engineering strain ε of coated yarn l This is a function of the engineering strain ε of the core fiber:

number

[0050] Here, l1 is as follows:

number

[0051] The equation relating to the length l1 of the coated yarn 20 in the stretched state can be derived as follows. First, the equation for the circumference of the core fiber 10 and the coated yarn 20 holds. Since the coated yarn 20 is wound spirally around the core fiber 10, the number of twists n is multiplied by the distance r1 between two twists in the stretched state and added to the circumference.

number

[0052] For n and D1, we use the formula already established above, and r1 2 n 2 Instead, parameter L1 2 Use this.

number

[0053] Now, we apply the equation obtained above to L1 and transform the equation into a quadratic equation.

number

[0054] In the selected material, ε is limited by the elastic limit, so the elongation can be considered elastic. Therefore, no large structural changes occur at the molecular level. From this, we can assume that the volume is constant and that Poisson's ratio is 0.5. From this, equation:

number

[0055] For l0, see the following formula:

number

[0056] ε onset is, ε l (ε) is defined as the value of ε that is positive.

number

[0057] By selecting D0, d, and ρ0 according to their ratios, the elongation of the core fiber 10 can be avoided, and the engineering strain ε of the covering yarn can be controlled. l (ε) is the maximum engineering strain of the core shape memory fiber 10 (ε max It can be made to be positive only when it exceeds ).

[0058] In this way, the covering yarn 20 is wrapped around the core fiber 10 and subjected to a predetermined engineering strain (ε max After elongation to ), the coated yarn deforms, and as the cSMPF elongates further, axial elongation of the coated yarn occurs. The core fiber 10 is subjected to the engineering strain (ε) at a temperature between the glass transition temperature and the melting point as defined in ISO 11357. max When stretched to the limit and released, the residual deformation is restored when heated at a temperature between 25°C and the melting point defined in ISO 11357. This means that the cSMPF containing the core fiber 10 will recover to ε=0 when heated at a temperature between 25°C and the melting point defined in ISO 11357.

[0059] In some embodiments of the coated shape memory polymer fibers according to the present invention disclosed herein, the core fiber (10) is selected from a shape memory polymer (SMP), the shape memory polymer being a thermally programmable shape memory polymer SMP having a crystalline rigid segment and a switching segment, wherein the thermally programmable shape memory polymer has a programming temperature (T) measured by differential scanning calorimetry (DSC). prog The temperature is 40 to 80°C, more preferably 40 to 70°C.

[0060] In the context of this patent application, differential scanning calorimetry (DSC) is defined as an analytical technique for measuring the thermal properties of shape memory polymers, particularly semicrystalline shape memory polymers, contained in coated shape memory polymer fibers (cSMPFs) used in the present invention. DSC is useful for measuring the thermal transitions of these materials, such as melting point, glass transition temperature, and crystallization behavior. This information is essential for understanding and optimizing the thermal response behavior of cSMPFs in the proposed compression garments.

[0061] Shape retention in one cycle (N) (R f ) and shape recovery (R r ) is the amount of deformation (ε) applied during programming. m ), fixed strain (ε) in the temporary shape after stress has been removed during the programming stage u ), and recovery strain (ε) in the recovery cycle p ) From this, the following formula:

number

[0062] In some preferred embodiments, the shape recovery rate of the coated fibers, particularly coated shape memory polymer fibers, is 80% to 100%, more preferably 92.5% to 100%, and most preferably 95% to 100%. This allows for repeated use in the disclosed applications. In the most preferred embodiment, the shape recovery rate of the coated fibers, particularly coated shape memory polymer fibers, is greater than 95%, satisfying the requirements of the RAL-387 standard for medical compression garments, particularly preferably in the Class 1 range with a pressure range of 2.4 kPa to 2.8 kPa.

[0063] To ensure and evaluate the long-term shape memory capacity of these fibers, approximately 100 shape memory cycles were performed. Throughout the 100 cycles, the same results were obtained regarding both shape recovery and low shape retention. For practical reasons and to shorten the cycle time, the heating and cooling rates were set to 10°C·min. -1 Therefore, the equilibrium time was shortened to 1 minute.

[0064] In a preferred embodiment of the coated shape memory polymer fiber of the present invention, the thermal programming process comprises the following steps: a) The coated shape memory polymer fibers are subjected to a predetermined programming strain (ε) lower than the maximum engineering strain, preferably at a controlled speed of ≤10 mm / min. prog While extending to a specific programming temperature (T prog The initial programming process includes controlling heating up to ) and then, b) A balancing step, which includes holding the extended state for an equilibrium time, preferably between 1 and 10 minutes, c) The coated shape memory polymer fiber is subjected to a predetermined programming strain (ε prog A cooling step is performed, which includes cooling to a temperature lower than the crystallization point, preferably ≤35°C, under the following conditions. Includes.

[0065] Programming temperature (T progThe temperature is preferably 40 to 80°C, more preferably 40 to 70°C, and is specific to each embodiment of the coated shape memory polymer fiber, depending on the overall shape memory polymer properties such as crystallinity, polymer type, and degree of crosslinking. Programming strain (ε prog Due to the elongation caused by the force, the polymer chains align in the direction of the applied force. In some preferred embodiments, the programming temperature can be within a numerical range obtained by combining any two of the following endpoint values: 40°C, 42°C, 44°C, 46°C, 48°C, 50°C, 52°C, 54°C, 56°C, 58°C, 60°C, 62°C, 64°C, 66°C, 68°C, 70°C, 75°C, or 80°C.

[0066] Particularly preferably, in the context of thermally programmable shape memory textiles and / or shape memory fabrics, the programming temperature is in the range of 40°C to 70°C, or may be a numerical range combining any two of the following endpoint values: 40°C, 42°C, 44°C, 46°C, 48°C, 50°C, 52°C, 54°C, 56°C, 58°C, 60°C, 62°C, 64°C, 66°C, 68°C, or 70°C. This allows the textile or fabric of the present invention to be programmed directly to the subject's body for a customized fit, without the risk of burning the subject.

[0067] In some embodiments of the present invention relating to coated shape memory polymer fibers (cSMPF) and / or shape memory textiles and / or shape memory fabrics containing the same, a temperature range is selected so that programming and / or shape recovery can be performed directly on the subject's body. Advantageously, this makes it possible to program and recover the coated shape memory polymer fibers and / or shape memory textiles and / or shape memory fabrics containing the same directly by heat to the subject's shape, thereby achieving optimal force distribution.

[0068] In some preferred embodiments, the shape-memory textile or fabric is programmed to conform to the contours of the patient's body. This means that the shape-memory textile or fabric is initially set to fit the patient's specific body shape. After wearing and removing, the programmed shape can be restored. This is particularly useful in medical garments where a custom fit is essential for therapeutic effect.

[0069] In another embodiment, the permanent shape of a shape-memory textile or shape-memory fabric is programmed at a high temperature exceeding the typical range of ambient temperature or body temperature. This ensures that the programmed shape is not inadvertently altered or distorted by routine activities such as washing or drying. In this case, the patient is not involved in the programming process. Instead, if deformation occurs during use, the garment's shape is restored when worn by the patient. Such garments, including cSMPF or shape-memory textiles or shape-memory fabrics, are designed to maintain their therapeutic shape and function regardless of routine handling, ensuring consistency and reliability in medical applications.

[0070] A thermally programmable shape memory polymer may be semi-crystalline, and vice versa. These two names, though distinct, refer to related properties of the shape memory polymer and are not mutually exclusive. In a preferred embodiment, the shape memory polymer is a thermally programmable semi-crystalline shape memory polymer.

[0071] In the most preferred embodiment, the shape memory polymer contained in the core fibers of the coated shape memory polymer fiber (cSMPF) is a semicrystalline shape memory polymer (SSMP) with a crystallinity of 3% to 70%, and is thermally programmable, with a programming temperature (T prog) represents a thermally programmable semicrystalline shape memory polymer with a temperature of 40 to 80°C. This has the technical effect of being preferably controlled by the method for producing cSMPF according to the present disclosure, and having a significant impact on the programming temperature, strain, and other parameters of the core fibers, so as to achieve a desired programming temperature essential for using cSMPF in clothing, shape memory fabrics, and shape memory textiles, particularly for thermal programming and recovery on the body of a subject.

[0072] The properties of the coated yarn range from natural fiber yarns such as cotton and wool to semi-synthetic or synthetic yarns such as viscose, acrylic, nylon, and polyester. In a more preferred embodiment of the coated shape-memory polymer fiber according to the present invention, the coated yarn is selected from cotton, wool, silk, linen, viscose, acrylic, nylon, and polyester.

[0073] In another preferred embodiment of the coated shape memory polymer fiber according to the present invention, the coated yarn is wound around the core fiber as a single or double twist having a twist in the S or Z direction.

[0074] The diameter ratio of the coating yarn to the core fiber is preferably in the range of 1:1 to 1:20. In a further disclosed embodiment of the coated shape memory polymer fiber according to the present invention, the diameter ratio of the coating yarn to the core fiber is preferably in the range of 1:1 to 1:20. A smaller diameter ratio ensures adequate coating and protection of the core fiber by the coating yarn, while a larger diameter ratio improves the flexibility and adaptability of the core fiber within the coating.

[0075] In cSMPF, the diameter of the core fibers is preferably in the range of 50 to 500 μm. In a preferred embodiment of the coated shape memory polymer fibers, the diameter of the core fibers is 50 to 500 μm.

[0076] The coated yarn may be a multifilament yarn or a monofilament yarn. However, monofilament yarn is preferred. In a preferred embodiment of the coated shape memory polymer fiber, the coated yarn is a monofilament yarn.

[0077] In a preferred embodiment, the core fiber (10) is a multifilament fiber, preferably with a linear fiber density of 15 to 1000 dtex, more preferably 35 to 600 dtex. A multifilament fiber is made up of a large number of thin individual filaments assembled into a single fiber. This structure may have several advantages, such as improved flexibility, increased strength, and improved fracture resistance. In a preferred embodiment, the linear fiber density of the core fibers of the cSMPF is within the range obtained by combining any two of the following endpoint values: 15dtex, 20dtex, 25dtex, 30dtex, 35dtex, 40dtex, 45dtex, 50dtex, 75dtex, 100dtex, 150dtex, 200dtex, 250dtex, 300dtex, 350dtex, 400dtex, 450dtex, 500dtex, 550dtex, 600dtex, 650dtex, 700dtex, 750dtex, 800dtex, 850dtex, 900dtex, 950dtex, and 1000dtex.

[0078] In preferred embodiments of the shape memory fabric, the core fibers contained in the cSMPF are multifilament fibers having a linear fiber density of 15 to 75 dtex, more preferably 20 to 50 dtex. In the shape memory fabric of the present invention, the linear fiber density of the contained cSMPF is selected from this range because a higher linear fiber density results in a fabric with the stiffness of the applications disclosed herein.

[0079] In another preferred embodiment relating to the shape memory textile, the core fibers contained in the cSMPF included in the shape memory textile are multifilament fibers having a linear fiber density of 250 to 750 dtex, more preferably 300 to 600 dtex. The linear fiber density of the included cSMPF is selected from this range because the amount of cSMPF fibers in the shape memory textile according to the present invention is small, as a lower linear fiber density results in a weaker shape memory effect.

[0080] In the context of textiles, "dtex" refers to "decitex," a unit of measurement used to express the linear density or fineness of a fiber. It is defined as the gram mass per 10,000 meters of fiber.

[0081] In the coated shape memory polymer fiber according to any one of the above claims, the coating yarn (20) is wound around the core fiber (10) at a rate of 500 to 6000 times per meter, preferably 750 to 3000 times. A higher twist rate ensures that the coating yarn is securely wound around the core fiber, providing stability and protection. At the same time, maintaining a twist rate within this range prevents excessive shrinkage of the core fiber, which could otherwise impair the shape memory function.

[0082] A coated shape memory polymer fiber according to any one of the claims, wherein the coated shape memory polymer fiber has an elasticity of 30 to 1000%, preferably 50 to 900%. This flexibility in elasticity means that the fiber can meet a variety of functional needs in applications where moderate or significant stretching is required. For example, high elasticity may be required for sports and leisure textiles, while moderate elasticity may be more suitable for medical or technical applications.

[0083] In preferred embodiments of coated shape memory polymer fibers (cSMPF), the elongation at break (ε) breakThe tolerance range is 500±150% to 1150±150%, preferably 600±150% to 1000±150%, including the error range. This provides a large safety margin even after the fibers are stretched beyond the engineering strain intended according to the present invention.

[0084] <Materials and shape memory polymers> The "shape memory polymer" according to the present invention is preferably a semi-crystalline polymer having a rigid segment and a switching segment. The rigid segment, also called the hard segment, is the part of the shape memory polymer that defines the permanent shape of the material by establishing intermolecular interactions. This segment allows the polymer to retain information of its original shape under various conditions and / or after deformation. The rigid segment may be formed by covalent bonds, molecular entanglement, microcrystals, or other molecular interactions. The switching segment of the shape memory polymer is responsible for the shape memory behavior of the material. This segment is designed to respond to external stimuli such as temperature changes. When exposed to a specific temperature associated with a phase transition, preferably the glass transition temperature and / or melting point, also called the programming temperature, the switching segment becomes flexible, and the shape memory polymer retains its shape memory information at the programming temperature (T prog ) with a certain programming distortion (ε prog After applying a stimulus, the shape can be temporarily changed after a specified equilibrium time. When the stimulus is removed, the segment returns to its original state controlled by the rigid segment, and the material returns to its predetermined shape. Switching segments can be formed by microcrystalline, glassy amorphous segments, or other reversible molecular interactions.

[0085] In preferred embodiments of the coated shape memory polymer fibers of the present invention, the shape memory polymer (SMP) is a semicrystalline shape memory polymer (SSMP) having a crystallinity of 3% to 70%, more preferably 5% to 60%, as determined by wide-angle X-ray scattering (WAXS), also known as X-ray diffraction spectroscopy (XRD). Alternatively, the crystallinity can preferably be determined by DSC. Crystallinity is a property that significantly affects the performance and applications of the shape memory polymer fibers according to the present invention. Specifically, in the case of semicrystalline shape memory polymers (SSMPs) used as the core of these fibers, crystallinity is directly related to the shape memory properties and mechanical properties. Importantly, crystallinity affects the phase transition temperature related to the programming of the coated shape memory polymer fibers. Preferably, the semicrystalline shape memory polymer is thermally programmable using crystallinity, more specifically the content of switching segments in the shape memory polymer, as an indicator of molecular structure, and affects the phase transition temperature and shape fixity related to the thermal programming of the shape memory polymer, as well as its shape memory performance.

[0086] In this invention, "crystallinity" is defined as the proportion of the polymer structure in the core fiber that is in a crystalline state. This crystalline state is characterized by an orderly and dense arrangement of molecules, in contrast to the disordered structure of the amorphous region. Crystallinity affects important properties of SMP, such as thermal responsiveness, mechanical strength, flexibility, and the effectiveness of the shape memory effect.

[0087] In the case of semicrystalline shape memory polymers (SSMPs) disclosed herein, the degree of crystallinity can be determined quantitatively and is usually expressed as a percentage. This percentage represents the ratio of the crystalline portion to the total volume of the polymer, which includes both crystalline and amorphous regions. The present invention particularly focuses on polymers having a crystallinity of 3% to 70%, more preferably 3% to 60%, and most preferably 3% to 50%, and may have a crystallinity within a numerical range obtained by combining any two of the following endpoint values: 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 13%, 15%, 17%, 19%, 21%, 23%, 25%, 27%, 29%, 31%, 33%, 35%, 37%, 39%, 41%, 43%, 45%, 47%, 49%, 51%, 53%, 55%, 57%, 59%, 61%, 63%, 65%, 67%, 69%, or 70%. Such a specific range of crystallinity is important for achieving a desired balance of material properties such as stiffness, flexibility, and phase transition temperature, ensuring optimal shape memory function and mechanical performance in various applications.

[0088] This invention uses wide-angle X-ray scattering (WAXS) to accurately determine the degree of crystallinity. This technique involves analyzing the diffraction pattern obtained from the polymer to distinguish between crystalline and amorphous regions. Such accurate determination of crystallinity is essential to ensure that coated shape memory polymer fibers meet the specific requirements and criteria necessary for their intended applications, such as textiles, medical devices, or other technical applications where shape memory and mechanical properties are critical. Such measurements can be performed using a Bruker D8 Discover X-ray diffraction system with a two-dimensional detector from Bruker AXS (Karlsruhe, Germany) and a suitable X-ray generator capable of generating, for example, copper K-alpha rays with a wavelength of 0.154 nm and operating at a voltage of 40 kV and a current of 40 mA. The beam can be focused and its geometric properties adjusted using state-of-the-art standard means and methods, such as a graphite monochromator and a pinhole collimator with an aperture of 0.8 mm. The sample needs to be irradiated for an appropriate time, for example, 60 seconds in transmission geometry, and the diffraction pattern can be recorded at a distance of 15 cm between the sample and the detector. The measurement can be performed at room temperature, and diffraction patterns were acquired at scattering angles from 8 to 42. The two-dimensional diffraction pattern can be integrated to obtain a plot showing the relationship between intensity and diffraction angle. These profiles can be analyzed using appropriate software known to those skilled in the art, such as Bruker's TOPAS software, to determine the degree of crystallinity (DOC), which is the ratio of the area of ​​the crystalline peak to the total area under the diffraction curve (the sum of the area of ​​the crystalline peak and the area of ​​the amorphous halo).

[0089] In preferred embodiments, the semicrystalline shape memory polymer (SSMP) includes, or is selected from, a semicrystalline polyester such as polycaprolactone, an ethylene-co-monomer such as poly[ethylene-co-vinyl acetate] (PEVA), poly(ethylene-1-octene), poly[ethylene-co-ethyl acrylate-co-maleic anhydride] (PEEAMA), poly[ethylene-co-(methyl acrylate)-co-(glycidyl methacrylate)] (PEMAGMA), a di- or multi-block copolymer such as an amorphous multi-block alicyclic polyether urethane (PEU) composed of poly(tetramethylene glycol) (PTMEG), 1,4-butanediol (1,4-BD), and methylenebis(p-cyclohexyl isocyanate) (H12MDI), or a semicrystalline ionomer such as perfluorosulfonic acid ionomer (PFSA). These shape memory polymers have been shown to be thermally programmable shape memory polymers with different programming temperatures and chemical properties. However, they are known to exhibit a degradation effect on their shape memory properties when subjected to strains exceeding the maximum engineering strain. As a result, they often do not recover even after multiple cycles, or they may suffer irreversible damage during programming. Therefore, it is the inventors' achievement that by combining the semi-crystalline shape memory polymer disclosed herein with a substantially non-stretchable yarn, a mechanically robust coated shape memory polymer fiber can be obtained over multiple thermal programming and recovery cycles.

[0090] Preferably, the semi-crystalline core fiber is selected from a shape memory polymer selected from the group consisting of polycaprolactone, poly[ethylene-co-vinyl acetate] (PEVA), poly(ethylene-1-octene), trans-polyoctenomer-containing polycyclooctene (PCO / TOR), poly[ethylene-co-ethyl acrylate-co-maleic anhydride] (PEEAMA), poly[ethylene-co-(methyl acrylate)-co-(glycidyl methacrylate)] (PEMAGMA), perfluorosulfonic acid ionomer (PFSA), and amorphous multi-block alicyclic polyether urethane (PEU) consisting of poly(tetramethylene glycol) (PTMEG), 1,4-butanediol (1,4-BD), and methylenebis(p-cyclohexyl isocyanate) (H12MDI). Most preferably, the semi-crystalline core fiber is poly[ethylene-co-vinyl acetate] (PEVA) polymer.

[0091] Furthermore, in a preferred embodiment of the coated shape memory polymer fiber, the core fiber is selected from a shape memory polymer selected from the group consisting of polycaprolactone, poly[ethylene-co-vinyl acetate] (PEVA), poly(ethylene-1-octene), trans-polyoctenomer-containing polycyclooctene (PCO / TOR), poly[ethylene-co-ethyl-co-maleic anhydride] (PEEAMA), poly[ethylene-co-(methyl acrylate)-co-(glycidyl methacrylate)] (PEMAGMA), perfluorosulfonic acid ionomer (PFSA), and amorphous multiblock alicyclic polyether urethane (PEU) consisting of poly(tetramethylene glycol) (PTMEG), 1,4-butanediol (1,4-BD), and methylenebis(p-cyclohexyl isocyanate) (H12MDI).

[0092] In a particularly preferred embodiment of the coated shape memory polymer fiber according to the present invention, the shape memory polymer comprises poly[ethylene-co-vinyl acetate] (PEVA), where poly[ethylene-co-vinyl acetate] is formed from poly[ethylene-co-vinyl acetate] polymer (PEVAP), preferably comprising a cross-linker and / or initiator, and is formed, for example, preferably by curing under UV, beta, or gamma rays.

[0093] In preferred embodiments of the present invention, the shape memory polymer fiber may be a "crosslinked shape memory polymer fiber." This fiber is characterized by improved structural integrity and enhanced shape memory properties due to the crosslinking process. Crosslinking within the polymer structure of the fiber is achieved, as described above, by incorporating a suitable crosslinking agent that reacts with the polymer chains to form stable crosslinks. The crosslinked shape memory polymer fiber may preferably be a covalently crosslinked polymer fiber.

[0094] Crosslinked shape memory polymer fibers may exhibit superior mechanical strength and shape recovery compared to non-crosslinked fibers. This is because crosslinking acts as a junction within the polymer matrix, influencing the rearrangement process and the crystallinity of the bulk material. The degree of crosslinking is carefully controlled to balance flexibility and rigidity, ensuring that the fibers recover their original shape after being temporarily deformed when exposed to certain stimuli, typically such as temperature changes.

[0095] Poly[ethylene-co-vinyl acetate] (PEVA), also known as covalently crosslinked poly[ethylene-co-vinyl acetate] (cPEVA), is, in the spirit of the present invention, a copolymer of vinyl acetate and ethylene, and is crosslinked by chemical means starting from poly[ethylene-co-vinyl acetate] polymer (PEVAP) to form new covalent bonds. Crosslinking can be induced by crosslinkers or crosslinking agents. Advantageously, in some embodiments, PEVA can be prepared by crosslinking different poly[ethylene-co-vinyl acetate] polymers, for example, PEVAP with different vinyl acetate content, together with crosslinking agents and / or initiators, and / or by curing.

[0096] In another preferred embodiment of the coated shape memory polymer fiber according to the present invention, the vinyl acetate content in the poly[ethylene-co-vinyl acetate] polymer is 5% to 50% of the total weight of the polymer. In a preferred embodiment of the present invention, the vinyl acetate content in the poly[ethylene-co-vinyl acetate] is 3 wt% to 45 wt% of the total weight, or, preferably, the degree of crystallinity may be a combination of any two of the following endpoint values: 3%, 5%, 7%, 9%, 11%, 13%, 15%, 17%, 19%, 21%, 23%, 25%, 27%, 29%, 31%, 33%, 35%, 37%, 39%, 41%, 43%, or 45%. This is because the VA content has a significant effect on properties such as the flexibility, thermal behavior, and shape memory properties of PEVA. An increase in VA content is associated with a decrease in crystallinity.

[0097] In this invention, the vinyl acetate content (VA-content) of PEVA and PEVAP can preferably be determined by differential thermogravimetric (DTG) analysis. Two decomposition stages are observed in PEVA and PEVAP, related to the formation of volatile products. The first peak of the DTG curve occurs in the temperature range of 300°C to 410°C, which may be due to the deacetylation of the VA segment, while a second peak occurs at higher temperatures around 420°C to 510°C, indicating the decomposition of the residue, which is caused by the cleavage of CC bonds along the main chain. Therefore, the composition of cPEVA is determined based on the weight reduction of acetate groups as follows:

number

[0098] In a preferred embodiment of the coated shape memory polymer fiber according to the present invention, the poly[ethylene-co-vinyl acetate] polymer (PEVAP) comprises a cross-linker and / or an initiator. The configuration in this context is achieved by mixing, preferably one, preferably at least two, poly[ethylene-co-vinyl acetate] polymers with different vinyl acetate content with a cross-linker, preferably TAIC, and an initiator, preferably BP, and then initiating crosslinking by irradiation (curing) to obtain PEVA, preferably covalently crosslinked PEVA.

[0099] An exemplary method for performing DSC measurements applicable to the present invention is outlined below. The DSC measurements were performed using a DSC 204 Phoenix (NETZSCH, Germany, Selb). This included a comprehensive heating-cooling-heating cycle for accurately evaluating the thermal properties of the PEVAP and PEVA shape memory polymers according to the present invention. The procedure began with an initial heating process, raising the temperature from room temperature to 200°C at a heating rate of 20°C per minute. This step was crucial in determining the behavior of the material during heating. After reaching 200°C, the sample underwent a cooling step down to -100°C. This cooling was performed at various rates, including 100°C / min, 50°C / min, 20°C / min, 10°C / min, 5°C / min, and 1°C / min. These various rates were used to accurately determine the temperature at which crystallization of the material occurs, which is a key factor in understanding the thermal behavior and stability of the material.

[0100] Following the cooling phase, a second heating experiment was conducted. In this phase, the samples were heated from -100°C to 200°C. During this second heating phase, the critical thermal transition temperatures, specifically the melting point and glass transition temperature, of the PEVAP and PEVA shape memory polymers were accurately measured.

[0101] Furthermore, the crystallinity index (χc) of the PE segment of PEVAP and PEVA shape memory polymers can be calculated from the exothermic curve obtained during DSC analysis. The crystallinity index is an important parameter indicating the degree of crystallinity within the polymer structure and affects the mechanical and thermal properties of the material. The calculation is given by the following formula:

number

[0102] [Table 1]

[0103] In some preferred embodiments of the coated shape memory polymer fibers according to the present invention, the amounts of crosslinking agents and initiators in the poly[ethylene-co-vinyl acetate] polymer range from 0.5% to 5.0% by weight.

[0104] In another preferred embodiment of the coated shape memory polymer fiber according to the present invention, the cross-linker is triallyl isocyanurate (TAIC).

[0105] In some more preferred embodiments of the coated shape memory polymer fibers according to the present invention, the amounts of crosslinking agents and initiators in the poly[ethylene-co-vinyl acetate] polymer are in the range of 1.0% to 2.0% by weight.

[0106] In a preferred embodiment of the coated shape memory polymer fiber according to the present invention, the crosslinking agent is benzophenone (BP).

[0107] In one embodiment of the present invention, the polymers are optionally present as a blend, and the content of each polymer in the blend is at least 10 wt%.

[0108] In some preferred embodiments, the content of each shape memory polymer in the blend is as follows: 1wt%, 3wt%, 5wt%, 7wt%, 9wt%, 11wt%, 13wt%, 15wt%, 17wt%, 19wt%, 21wt%, 23wt%, 25wt%, 27wt%, 29wt%, 31wt%, 33wt%, 35wt%, 37wt%, 39wt%, 41wt%, 43wt%, 45wt%, 47wt%, 49wt%, 51wt%, 53wt%, 55wt%, 57wt%, 59wt%, 61wt%, 63wt%, 65wt%, 67wt%, 69wt%. The values ​​can be any combination of 71wt%, 73wt%, 75wt%, 77wt%, 79wt%, 81wt%, 83wt%, 85wt%, 87wt%, 89wt%, 91wt%, 93wt%, 95wt%, 97wt%, or 99wt%, with the total polymer content in the blend being 100wt%.

[0109] In another embodiment, the hard segment content such as (H12MDI) / (1,4-BD), polyethylene-co-monomer content, and trans-double bond content in the polymer may preferably vary between 40% and 95%. In some preferred embodiments, the hard segment content in 1,4-butanediol (1,4-BD) and methylenebis(p-cyclohexyl isocyanate) (H12MDI), and the trans-1,4-butadiene monomer block content may vary in the polymer, preferably in the range of 1 to 50 mol%.

[0110] The amount of vinyl acetate in the poly[ethylene-co-vinyl acetate] polymer can preferably vary in the range of 5% to 50% of the total polymer weight. In one embodiment of the present invention, the poly[ethylene-co-vinyl acetate] polymer (PEVAP) contains a cross-linker such as triallyl isocyanurate (TAIC) and / or an initiator such as benzophenone (BP). Preferably, the amount of crosslinking agent and initiator in the poly[ethylene-co-vinyl acetate] polymer is 0.5% to 5.0% by weight, for example, in the range of 1.0% to 2.0% by weight.

[0111] In this disclosure, the terms “cross-linker,” “crosslinker,” and “crosslinking agent” are synonymous and refer to compounds used to establish crosslinks within a polymer matrix. These agents are characterized by having at least two reactive functional groups essential for forming crosslinks, such as covalent bonds, between separate polymer chains and / or between different segments of the same polymer chain. In another mechanism, certain cross-linkers act by forming reaction sites directly on the polymer chain. These sites then react with each other to promote crosslinking. Strong acids or peroxides are typically used in this type of crosslinking.

[0112] The ratio of cross-linkers to the total weight of the polymer is a crucial factor as it significantly affects the degree of crosslinking. Preferably, the ratio of cross-linkers to the total weight of the shape memory polymer or its precursor before the start of the crosslinking process is in the range of 0.05 wt% to 5 wt%. More specifically, the optimal range for improving the balance between the effectiveness and properties of the resulting polymer is 0.1 wt% to 2.5 wt%. This ratio is extremely important in influencing the final properties of the shape memory polymer, particularly its crosslinking density, mechanical strength, and thermal responsiveness.

[0113] In shape memory polymers, the level of crosslinking, also known as the "degree of crosslinking," is particularly important. Higher crosslinking grades tend to result in lower crystallinity, especially crystallineity, within the polymer. This relationship is crucial in the design of shape memory polymers. Crystallinity directly affects the transition temperature of these semi-crystalline polymers and is a key factor in tuning their thermal response behavior to meet the specific requirements of the present invention. Therefore, careful consideration is needed regarding the selection and concentration of crosslinkers to achieve the desired balance between the degree of crosslinking and crystallineity, ensuring that the shape memory polymer performs optimally in its intended application.

[0114] In the case of ethylene-co-monomer polymers, or di- or multi-block copolymers, comprising at least one polyethylene and / or polyalkene polymer block, the cross-linker is preferably a substance having at least two, more preferably two to four, alkene functional groups, preferably allyl or vinyl groups. These cross-linkers can react with radicals generated on the polymer, preferably shape memory polymers in the sense of the present invention, by irradiation and / or an initiator, preferably a photoinitiator such as benzophenone (BP). This has the advantage that functional groups are not required for this crosslinking, although some functional groups, such as acetate groups, can be radically crosslinked, and the degree of crosslinking may be affected by the irradiation time and / or dose, and / or the concentration of the initiator and / or crosslinking agent, resulting in a variety of parameters suitable for a wide range of shape memory polymers.

[0115] The gel content and crosslinking grade in a polymer are closely related concepts in polymer chemistry. In certain embodiments of the present invention, the shape memory polymer, preferably a crosslinked shape memory polymer, most preferably a covalently crosslinked shape memory polymer, is characterized by having a gel content in the range of 60 to 100%, and more preferably in the range of 70 to 100%. This embodiment is particularly important in ensuring the desired physical and mechanical properties of the shape memory polymer used in a variety of applications. In some preferred embodiments, the gel content of the shape memory polymer may be a numerical range combining any two of the following endpoint values: 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 97%, 98%, 99%, and 100%.

[0116] In this embodiment, the polymers constituting the core fibers, or blends thereof, can be crosslinked by various mechanisms, such as covalent bonding, ionic interactions, or microcrystal formation. However, this embodiment focuses on covalently crosslinked polymer networks, which are known for their robustness and stability. According to standards such as ASTM D2765 or ISO 10147, these covalently crosslinked polymers exhibit a gel content of 60 to 100%.

[0117] To measure the gel content (G) of crosslinked core fibers, particularly the crosslinked shape memory polymer within these fibers, a solvent extraction method is used. This involves immersing the polymer sample in a solvent such as toluene or xylene at a constant temperature of 110°C or below. The extraction process is carried out for 24 hours, after which the solvent is evaporated for another 24 hours in a vacuum oven set to 45°C. The gel content is expressed by the following formula:

number

[0118] For the purposes of this embodiment, it is important to note that the fibers that are not extracted are used for coating and various investigations such as thermomechanical analysis and evaluation of shape memory properties.

[0119] This embodiment highlights the relationship between gel content and degree of crosslinking in polymer chemistry. It demonstrates that higher gel content leads to a more extensive crosslinking network, which is essential for achieving desired shape memory properties. The specific range of gel content described above ensures that the polymer maintains an optimal balance between flexibility and structural integrity, making it ideal for applications requiring precise and reliable shape memory functionality.

[0120] In some preferred embodiments of coated shape memory polymer fibers (cSMPF), the modulus of elasticity (E), also known as Young's modulus, is preferably 1.0 ± 0.5 to 15.0 ± 0.5 MPa, and more preferably 2.0 ± 0.5 to 10.0 ± 0.5 MPa, measured at 25°C. This allows for a wide range of applications requiring different stresses and strains.

[0121] <Manufacturing method> The present invention further relates to a method for producing coated shape memory polymer fibers as disclosed herein, comprising the steps of extruding core fibers of poly[ethylene-co-vinyl acetate] polymer, optionally extruding them together with a cross-linker or crosslinking agent, optionally curing the extruded fibers to covalently crosslink them, and winding a coating yarn around the core fibers.

[0122] In a preferred embodiment of the method of the present invention, curing is performed under UV, beta, or gamma rays.

[0123] In another aspect, the present invention relates to a method for producing coated shape memory polymer fibers (cSMPF). This method includes the steps of: extruding core fibers of poly[ethylene-co-vinyl acetate] polymer together with an optional cross-linker or crosslinking agent; optionally curing the extruded fibers for covalent bonding by irradiation with radiation such as UV, beta, or gamma rays; and winding a coating yarn around the core fibers. Alternatively, crosslinking can be performed by heating to a temperature below the melting point of a particular polymer as defined in ISO 11357, and the elongation of the extruded core fibers can be up to 10 times compared to the unelongated extruded fibers. This is preferably done by stretching the fibers by passing them through a cooling bath and winding them onto a bobbin with a predetermined tension or force.

[0124] The present invention further relates to a method for producing coated shape memory polymer fibers (cSMPF) according to any one of the above claims, comprising the following steps: a) A step of extruding the core fibers (10) of the core fiber precursor for the shape memory polymer according to the present invention, preferably together with a cross-linker or crosslinking agent, and more preferably together with a poly[ethylene-co-vinyl acetate] polymer, optionally together with a cross-linker or crosslinking agent, then, b) A step of curing the extruded fibers, preferably under UV, beta, or gamma rays for covalent crosslinking, then, c) A process of wrapping the covering yarn (20) around the core fiber (10). Includes.

[0125] In this invention, "curing" refers to a process that induces crosslinking within a shape memory polymer, typically aiming for covalent crosslinking. This process stabilizes the polymer structure and significantly affects its mechanical properties, thermal properties, and, most importantly, its shape memory properties. In the case of polymers containing ethylene or olefin monomers, as in this invention, curing can involve direct radical crosslinking. This is often achieved using a photoinitiator such as a peroxide and / or benzophenone as an initiator, and preferably a crosslinking agent such as TAIC. The initiator decomposes under specific conditions, such as thermal activation or electromagnetic radiation irradiation, generating free radicals, which promote the formation of covalent bonds between polymer chains.

[0126] In this first step, a core fiber precursor, formulated to form a shape memory polymer, is extruded. In some preferred embodiments, the precursor is poly[ethylene-co-vinyl acetate] polymer (PEVAP). Optionally, a cross-linker or crosslinking agent is included in the mixture. The presence of a cross-linker is crucial if improved structural integrity or specific mechanical properties, including shape memory properties, are desired in the final cSMPF.

[0127] Alternatively, curing can be performed using irradiation methods such as UV, beta, or gamma rays, in combination with an initiator and, if necessary, a cross-linker. In these methods, the extruded polymer is exposed to high-energy radiation to generate free radicals and initiate the crosslinking process. Irradiation provides a controlled crosslinking method, allowing for precise manipulation of the polymer's properties.

[0128] After curing, the covering yarn is wrapped around the core fibers. This yarn is typically substantially non-stretchable and provides the core fibers with additional structural support and protection.

[0129] In preferred embodiments of the present invention, the shape memory polymer precursor is prepared prior to step a) by a comprehensive formulation process. This process involves several carefully controlled steps to ensure optimal mixing of the polymer and reagents, preferably initiators and cross-linkers.

[0130] In some preferred embodiments, a 50:50 mixture of initiator and cross-linker, preferably BP and TAIC, is prepared. This mixture is then manually mixed with a shape memory polymer precursor, such as PEVAP (poly[ethylene-co-vinyl acetate]) polymer granules. This manual mixing ensures a preliminary and uniform dispersion.

[0131] Next, the manually mixed materials are mixed in a twin-screw extruder. The extruder is set to a specific temperature profile: 25°C in the feed zone, gradually increasing to 80°C, then maintaining 110°C throughout the melting and mixing zones, and finally reaching 100°C at the die. The screw rotation speed is preferably 30-60 rpm, more preferably 45-55 rpm. This controlled environment ensures complete mixing and melting of the components, resulting in a homogeneous mixture.

[0132] After the initial extrusion, the continuous filament can be cut into granules. This pelletizing process transforms the extruded blend into easy-to-handle granules, facilitating further processing and handling. Furthermore, this blend can be stored under controlled conditions for further processing, which is advantageous.

[0133] In some preferred embodiments, the shape memory polymer precursor may be pelletized and extruded multiple times to obtain a more uniform distribution.

[0134] Preferably, the granules are dried overnight at a temperature of 30 to 80°C, preferably 35 to 55°C. This drying step is important to remove any residual moisture that could potentially interfere with the subsequent curing process of the polymer.

[0135] In preferred embodiments, the shape memory polymer fibers before curing are supplied as monofilaments with a diameter of 0.05 mm to 0.5 mm. This diameter range is selected to balance the mechanical strength and flexibility of the fibers. Preferably, the mixture is fed into a single-screw extruder and extruded. The extruder is equipped with filament dies of various diameters to produce monofilaments of the desired thickness, as disclosed herein. In some embodiments of the extrusion process, the feed zone can be maintained at 20°C to prevent premature melting of the mixture. The temperature can then be raised to 80°C, followed by maintaining a constant temperature of 110°C throughout the melting zone. Finally, the die temperature is set to 100°C. This controlled temperature profile is important to achieve uniform melting and a smooth flow of polymer through the die. The screw rotation speed during extrusion is maintained between 5 and 20 rpm. This rotation speed range allows for careful control of the extrusion process and ensures that the monofilaments are extruded at a constant speed and with a uniform diameter.

[0136] In another preferred embodiment, the shape-memory polymer fibers before curing are provided as multifilaments with a linear density of 40 to 500 dtex. This can be achieved by melt spinning, which has a configuration similar to extrusion but differs in that it uses a spinneret at the end. The spinneret preferably contains 20 to 200, more preferably 36 to 150 holes, through which multiple filaments are extruded. Preferably, the filaments are extruded simultaneously and assembled into a single continuous filament. This process can produce a bundle of filaments that can be used for a variety of textile applications.

[0137] In some preferred embodiments, the shape memory polymer fibers are cured by in-line UV irradiation incorporated into the fiber extrusion process. This method allows for immediate crosslinking of the fibers during manufacturing, streamlining the manufacturing process. Alternatively, crosslinking can be performed as a post-processing step, which can be carried out by UV irradiation or electron beam irradiation.

[0138] Electron beam irradiation can be performed at different doses, preferably 50 to 200 kGy, and particularly preferably 90 to 170 kGy, thereby achieving different degrees of crosslinking depending on the specific requirements of the application. This type of irradiation is particularly effective in achieving high degrees of crosslinking by inducing free radicals in the polymer, and is advantageous for applications requiring robust shape memory properties.

[0139] <Shape-memory textiles and fabrics> In a further embodiment, the present invention relates to a shape memory fabric comprising or comprising a coated shape memory polymer fiber (cSMPF) comprising a core fiber (10) and a substantially non-stretchable coated yarn (20) according to the present invention, wherein the coated shape memory polymer fiber (cSMPF) is a) A shape memory mesh network in which cSMPF is interwoven or entangled, preferably by techniques such as knitting, weaving, crocheting, or intarsia, to form a structure that is connected in a functional manner, and / or b) A shape memory inlay placed on a second fabric, preferably a non-shape memory fabric. Placed, Here, the maximum engineering strain of the core fiber (10) is reduced to below the strain at the yield point of the uncoated core fiber (10). This has the advantage that, as disclosed herein, the robust shape memory effect of the cSMPF is coordinated with the surrounding fibers, so that the entire textile uniformly exhibits the desired shape memory properties.

[0140] "Non-shape memory fabric" refers to a fabric that does not contain or is not composed of coated shape memory polymer fibers (cSMPF) according to the present invention. Common fabrics are known to those skilled in the art. Preferably, further and / or second fabrics are non-shape memory fabrics. This allows for the integration of well-defined fabrics known in the prior art, to which the shape memory effect of cSMPF according to the present invention can be added.

[0141] In the spirit of this invention, the term "woven" refers to a method of arranging coated shape memory polymer fibers (cSMPF) by regularly crossing them vertically. For example, as defined in ISO 3572:1976, this weaving process forms a fabric or mesh network in which cSMPF intersects at regular intervals, forming a lattice structure. In woven designs, various weave patterns can be created by arranging cSMPF vertically or at other angles. By weaving cSMPF, the shape memory effect is uniformly distributed throughout the fabric, ensuring consistent performance and functionality.

[0142] On the other hand, entanglement is achieved by twisting or intertwining cSMPF fibers, rather than following a regular up-and-down weaving pattern. This technique results in a more flexible, unstructured arrangement of fibers. Entangled cSMPF fibers create a fabric in which the fibers are looped or knotted with each other, forming a network that enhances flexibility and adaptability in textile design while maintaining shape-memory properties.

[0143] In both interwoven and interwoven configurations, cSMPF forms a functionally interconnected structure. This structure resembles a mesh network or fabric, where individual fibers contribute to the overall shape-memory function of the textile. Functional interconnection means that the movement or deformation of one fiber influences and coordinates surrounding fibers, allowing the entire textile to uniformly exhibit the desired shape-memory properties.

[0144] A textile manufacturing engineer would understand the various methods of arranging fibers to form such functional interconnected structures. Techniques such as knitting, weaving, braiding, and knotting can be used to create shape-memory fabrics. The choice of technique depends on the properties required of the final product, such as flexibility, elasticity, strength, and the specific shape-memory properties desired.

[0145] Furthermore, the present invention encompasses the concept of shape memory inlay, which involves embedding or integrating cSMPF into a second fabric, preferably a non-shape memory fabric. This inlay technique allows shape memory properties to be incorporated into conventional fabrics, improving functionality without altering their fundamental properties. This integration can be achieved not only by specific knitting processes but also by sewing, adhesive bonding, or other methods known to those skilled in the art.

[0146] Furthermore, the present invention relates to a shape memory textile comprising a coated shape memory polymer fiber (cSMPF) according to the present invention, at least a further fabric, preferably an uncoated shape memory fabric, and / or further fibers, preferably uncoated shape memory fibers, wherein the cSMPF is arranged in and / or on the shape memory textile by knitting, preferably circular knitting, plain knitting, jacquard knitting, preferably inlay weaving, or layer weaving, knitting, embroidery, composite techniques, or a 3D textile structure, and the maximum engineering strain of the core fibers (10) is reduced to below the strain at the yield point of the uncoated core fibers (10). This specification ensures that the structural integrity and shape memory properties of the cSMPF are maintained within the textile and prevents overstretching and potential damage to the fibers.

[0147] In this invention, knitting is used as a preferred method for incorporating coated shape-memory polymer fibers (cSMPF) into shape-memory textiles. This technique allows for the production of fabrics using interconnected loops of yarn, which can be finished into various shapes. Circular knitting is a preferred method for producing seamless, tubular structures, knitted in a continuous circular motion. This technique is ideal for the manufacture of socks, tubular objects, and other circular garments. Incorporating cSMPF into circular knitting enables innovative applications such as tubular compression garments with shape-memory properties. Plain knitting, which knits in rows back and forth, allows for the expression of more complex designs and patterns. Plain knitting is suitable for producing larger, flatter fabrics that can be cut and sewn into specific garments. Using cSMPF in plain knitting allows for the production of shape-memory fabrics with complex shapes and intricate designs. Jacquard knitting is a special knitting method that can produce multi-colored and complex patterns. By using cSMPF in jacquard knitting, not only are functional shape-retention properties added, but the aesthetic appeal of the fabric is also improved, making it suitable for fashion and design-oriented applications.

[0148] The embroidery technique applied in this invention is a method of decoratively sewing coated shape-memory polymer fibers (cSMPF) onto a base fabric. This technique allows for precise placement of the cSMPF and the addition of shape-memory functionality to specific patterns or designs. Embroidery can be used to create localized areas with shape-memory properties, thereby adding functional value such as adaptive fit or dynamic structural support to specific areas of textiles in sports and leisure clothing, as well as in specialized medical applications such as bandages for individual burns and scars.

[0149] Composite technology refers to the formation of composite textiles by combining cSMPF with other materials. This method involves layering, bonding, or embedding cSMPF with other fabrics or materials, thereby improving the overall properties of the textile. As a result, the shape memory properties of cSMPF are integrated with the structural, thermal, or other properties of the different materials, creating a synergistic combination. Composite technology is particularly useful in applications where a balance of flexibility, strength, and adaptive shape memory is required.

[0150] Braiding involves intertwining multiple cSMPF threads, and potentially other types of fibers, in a regular pattern. This method provides a unique way to manufacture textiles with shape memory properties, superior strength, flexibility, and durability. Braided structures are particularly suitable for applications requiring high tensile strength and resilience, such as medical devices, protective clothing, or structural applications where the shape memory effect can be utilized for dynamic functionality. The braiding process allows for the creation of complex three-dimensional textile structures with enhanced shape memory properties.

[0151] Furthermore, the present invention relates to a method for manufacturing shape memory textiles and / or shape memory fabrics, and the following steps: a) A step of preparing coated shape memory polymer fibers (cSMPF), then, b) The process of arranging coated shape memory polymer fibers (cSMPF) in and / or on a textile or fabric, preferably by knitting, particularly preferably by circular knitting, plain knitting, jacquard knitting, weaving, particularly preferably by inlay weaving, overlay weaving, braiding, embroidery, composite techniques, or 3D textile structuring. Includes.

[0152] In summary, this method for manufacturing shape-memory textiles or fabrics is characterized by its versatility and adaptability. By selecting and combining various techniques for deploying cSMPF, a wide range of textiles and fabrics with customized shape-memory properties can be produced. This approach enables the development of innovative products suitable for a variety of applications, from clothing and accessories to medical devices and industrial materials.

[0153] The first stage of the supply process involves the manufacture or procurement of cSMPF, which are the basic components of shape-memory textiles or fabrics. These fibers are characterized by a structure in which a shape-memory polymer is at the core, covered with non-stretchable yarn. The composition, thickness, and properties of these fibers are selected based on the properties required for the final textile or fabric.

[0154] <Use of coated shape-memory polymer fibers> Furthermore, it is disclosed that the coated shape-memory polymer fibers described herein may be used in compression garments, orthopedic bandages, braces, posture-correcting garments, push-up garments, corsets and corsages, and sportswear.

[0155] In another aspect, the present invention relates to the use of coated shape-memory polymer fibers (cSMPF). cSMPF can be used, for example, in compression garments, orthopedic bandages, braces, posture-correcting garments, push-up garments, corsets and corsages, and sportswear.

[0156] One embodiment of the present invention relates to a shape memory polymer fiber (SMPF) for textile or medical applications, in which shape retention and recovery are maintained at a constant level over multiple shape memory cycles. The present invention relates to a core fiber of a semicrystalline polymer fiber and the maximum engineering strain (ε) of the core shape memory fiber. max ) is the yield strain (ε) of the uncovered core fibers. yield The present invention provides a coated shape memory polymer fiber (cSMPF) having a substantially non-stretchable coating yarn wound around a core fiber to reduce the stretchability to a minimum. Thus, the coating yarn is used to limit the stretchability or deformation of the core shape memory fiber during programming and to ensure maximum recovery strain.

[0157] [Table 2]

[0158] Furthermore, the present invention discloses the use of coated shape-memory polymer fibers in textiles, preferably shape-memory textiles such as textiles for technology, medical, orthopedic, industrial, sports, or leisure.

[0159] Preferably, the coated shape-memory polymer fibers are used in fabrics, preferably shape-memory fabrics such as those for technology, medical, orthopedic, industrial, sports, or leisure.

[0160] Particularly preferred is the use of shape-memory textiles or shape-memory fabrics as medical, orthopedic, and / or compression garments, preferably as repeatedly thermally programmable medical, orthopedic, and / or compression garments by heating them to 40 to 70°C on the subject's body. This improves comfort and effectiveness without the risk of causing burns to the subject's body.

[0161] Furthermore, preferred is the use of shape-memory textiles or shape-memory fabrics as sports or leisure clothing, preferably as sports or leisure clothing that can be repeatedly thermally programmed by heating them to 40 to 70°C on the subject's body.

[0162] In a preferred embodiment, the shape-memory textile and / or shape-memory fabric is specially tailored for individuals aged 50 to 90 years. This embodiment is designed to address age-related symptoms such as poor circulation, edema, and varicose veins, as well as support during post-surgical recovery. The garment features graduated compression that promotes blood flow, normalizes blood reflux, reduces swelling, and improves overall comfort, making it suitable for everyday wear and for increasing mobility in this age group.

[0163] Another embodiment focuses on athletes and sports enthusiasts aged 15 to 50. This version of the shape-memory textile and / or shape-memory fabric is designed to support muscle recovery, reduce fatigue, and improve athletic performance. It employs materials and designs suitable for high-intensity activities and endurance sports. This garment is optimized for activities such as running, cycling, and team sports, where the amount of muscle exertion and the need for support are significant.

[0164] Another embodiment of shape-memory fibers and / or shape-memory fabrics is in compression therapy applications where highly personalized clothing and / or bandages are required to suit individual cases. In these applications, such as the treatment of burns, scars, or ulcers, individual fit and / or compression profiles are required depending on the patient's physical deformities or prescribed treatment.

[0165] Dedicated embodiments of shape-memory textiles and / or shape-memory fabrics are designed for pregnant women. These garments are tailored to accommodate the changing body during pregnancy, providing support and comfort while managing symptoms such as leg swelling. The design ensures safety and ease of use, making it a practical solution for everyday wear during pregnancy.

[0166] One embodiment of the present invention is specifically designed for people suffering from lymphatic disorders such as lymphedema. The shape-memory textile and / or shape-memory fabric is designed to promote lymphatic fluid circulation and reduce swelling and discomfort associated with lymphatic fluid accumulation. Its unique structure is intended to provide targeted support to the affected area. The shape-memory effect and thermally programmable properties enable a customizable solution tailored to the individual.

[0167] Further embodiments address the individual needs of those with limited mobility and / or who have particular difficulty putting on and taking off compression garments. Shape-memory textiles and / or shape-memory fabrics can simplify this process through a procedure based on the shape-memory effect, thereby making it easier to put on compression garments and then adjust them to the desired fit and compression, as well as making it easier to take off compression garments without causing significant irreversible damage to their therapeutic properties.

[0168] A preferred embodiment addresses the needs of individuals with posture problems or those who lead sedentary lifestyles. Memory foam textiles and / or memory foam fabrics provide posture support, particularly for individuals who sit for long periods or whose occupations cause posture problems. Their design focuses on promoting correct posture and reducing strain on the back and legs.

[0169] Special embodiments have been developed for long-distance travelers, especially those on long flights. This shape-memory textile and / or shape-memory fabric is designed to prevent cardiovascular problems such as deep vein thrombosis (DVT). Its compression properties, which promote blood flow in the lower extremities, make it an essential travel item for health-conscious travelers.

[0170] Finally, one embodiment is designed for individuals engaged in occupations requiring prolonged standing or heavy labor. The shape-memory textile and / or shape-memory fabric of this embodiment reduces leg fatigue during long hours of work, supports muscular endurance, and improves overall comfort. It is particularly beneficial for workers in fields where physical strain is a constant element of the job, such as healthcare, construction, and retail.

[0171] The present invention also relates to thermally programmable textiles, such as thermally programmable textiles for technical, medical, orthopedic, industrial, sports, or leisure use, which include or consist of coated shape-memory polymer fibers or shape-memory fabrics or shape-memory textiles according to the present invention, preferably having a compression pressure of 0.5 to 8.5 kPa. These compression levels are extremely important in medical applications such as improving blood circulation, reducing edema, and supporting injured or weakened body parts. A further advantageous feature of these garments is their thermally programmable nature in the range of 40 to 70°C, which allows for easy adjustment of the compression level to suit the subject's body and adaptability to various stages of recovery or levels of edema.

[0172] The present invention discloses a preferred use of a thermally programmable textile as medical or orthopedic clothing, preferably having a compression pressure of 0.5 to 8.5 kPa and preferably being repeatedly thermally programmable by heating to 40 to 70°C on the body of a subject.

[0173] Furthermore, the present invention discloses the use of a thermally programmable textile as sports or leisure clothing, preferably having a compression pressure of 0.5 to 8.5 kPa, and preferably being repeatedly thermally programmable by heating to 40 to 70°C on the subject's body.

[0174] Furthermore, the present invention relates to a thermally programmable fabric, such as a shape-memory fabric for technical, medical, orthopedic, industrial, sports, or leisure use, which includes or comprises coated shape-memory polymer fibers, shape-memory fabrics, or shape-memory textiles, preferably having a pressing pressure of 0.5 to 8.5 kPa.

[0175] The present invention discloses a preferred use of a thermally programmable fabric as medical or orthopedic clothing, preferably having a compression pressure of 0.5 to 8.5 kPa, and preferably being repeatedly thermally programmable by heating to 40 to 70°C on the body of a subject.

[0176] Furthermore, the present invention discloses a preferred use of a thermally programmable fabric as sports or leisure clothing, preferably having a compression pressure of 0.5 to 8.5 kPa and preferably being repeatedly thermally programmable by heating to 40 to 70°C on the subject's body.

[0177] <Definition> In the following explanation, certain terms and their derivatives are used for convenience, but there is no intention to limit the scope to these. For example, terms such as "up," "upward," "upward," "down," "downward," "downward," "left," and "right" refer to directions in the reference drawings unless otherwise specified. Similarly, terms such as "inward" and "outward" refer to directions toward or away from the geometric center of a device or area, or a particular part thereof. Unless otherwise specified, singular references include plural references, and vice versa.

[0178] In this patent application, the term “Subject” refers to any individual or group that may benefit from the use of the coated shape memory polymer fibers (cSMPF) and / or shape memory textiles and / or shape memory fabrics containing them as disclosed herein.

[0179] "Programming," particularly "thermal programming" or "programming by heat," refers to the process of reversibly changing the shape of coated shape memory polymer fibers, including or comprising a core fiber made of a shape memory polymer. The shape and properties of the shape memory polymer can be changed by rearranging and equilibrating crystalline rigid segments and switching segments. Thermally programmable shape memory polymers can be programmed by specific thermal programming processes.

[0180] Finally, it should be noted that all features described in the application documents, particularly in the dependent claims, should be granted independent protection individually or in any combination, despite formal references to one or more specific claims. Further advantages, features, and possible uses of the present invention are also evident from the following description of embodiments and drawings. All features described and / or illustrated, individually or in any combination, constitute the object of the present invention, independently of the abstract in the claims or their references. Features described in the claims and specification may each be essential to the present invention, individually or in any combination.

[0181] Furthermore, those skilled in the art will undoubtedly understand that the individual features described in the above-described specific embodiments can be combined with each other in appropriate ways, provided that no contradictions arise. Therefore, to avoid unnecessary repetition, it is omitted to describe each possible combination individually. [Examples]

[0182] The present invention will be described in more detail with reference to the following drawings and embodiments, but will not be limited thereto. In particular, the features shown in the individual drawings and described for each embodiment will not be limited to the individual embodiments.

[0183] To illustrate the basic principle of the apparatus according to the present invention, an example of an embodiment is shown. It should be noted that the ratios, dimensions, degree of deformation, or displacement of the components according to the present invention are different from those of reality for illustrative purposes.

[0184] Unless otherwise specified in the context, the singular form includes the plural form. The features, characteristics, and advantages of the present invention described above, as well as the methods by which they are achieved, will be more clearly understood in the context of the following description of embodiments. Where the term “can be used” in this application, it refers to both technical possibility and actual technical implementation.

[0185] The present invention will be described in detail below with reference to exemplary embodiments illustrated with drawings. Figure 1 shows a schematic diagram of the coated shape memory polymer fiber (cSMPF) according to the present invention. Figure 2A shows a schematic diagram of the coated shape memory polymer fiber (cSMPF) according to the present invention in its non-extended state. Figure 2B shows a schematic diagram of the elongated state of the coated shape memory polymer fiber (cSMPF) according to the present invention. Figure 3A shows a schematic diagram of an exemplary semicrystalline shape memory polymer cured using radiation, a benzophenone initiator, and a trifunctional cross-linker (FG = functional group, e.g., an ethylene group). Figure 3B shows a schematic diagram of the curing process from PEVA polymer to PEVA (covalently crosslinked PEVA) by initiators and crosslinkers, and illustrates some of the possible covalent crosslinking sites according to the present invention. Figure 4A shows an example of thermally programming a shape-memory textile, including coated shape-memory polymer fibers (cSMPF), in a laboratory environment. Figure 4B shows an example of thermally programming a shape-memory textile containing coated polymer shape-memory fibers (cSMPF) on a subject's body.

[0186] Figure 1 shows an exemplary embodiment of a coated shape memory polymer fiber (cSMPF) having a core fiber (10) and a substantially non-stretchable coating yarn (20) wound around the core fiber (10). The coating yarn (20) is the maximum engineering strain (ε) of the core fiber (10). max ) is the strain (ε) at the yield point of the uncoated core fiber (10). yield The core fibers (10) are wrapped around the core fibers (10) so that the amount of the energy is reduced to less than 100%.

[0187] The present invention defines a cSMPF structure with the aim of preventing excessive elongation of the core fibers 10 and preventing irreversible plastic deformation, mechanical properties, shape memory properties, and shape degradation of the core fibers 10.

[0188] Figures 2A and 2B illustrate exemplary embodiments of two states of a coated shape memory polymer fiber. In both states, the coated shape memory polymer fiber comprises a core fiber 10 and substantially non-stretchable coating yarn 20 wound around the core fiber 10. In Figure 2A, the core fiber 10 is in a non-stretched state. Figure 2B shows the core fiber 10 in a stretched state. During programming (from Figure 2A to Figure 2B) and recovery (from Figure 2B to Figure 2A), the coil / twist spacing of the coating yarn 20 can be seen to change as the core fiber 10 is mechanically deformed. As the core fiber 10 around which the coating yarn 20 is wound stretches (extends), the pitch of the coating yarn 20 around the core fiber 10, i.e., the distance between twist loops, increases from r0 to r1, thereby decreasing the entanglement density (ρ1).

[0189] Figure 3A is a schematic diagram of a typical semi-crystalline shape memory polymer, illustrating the curing process by radiation. In this process, a photoinitiator and a trifunctional cross-linker are used, with each functional group (FG), such as the ethylene group, actively participating in the crosslinking reaction. This figure highlights the molecular structure of the polymer before and after the crosslinking process. It shows how the functional groups of the crosslinking agent interact with the polymer chains to form a network structure that imparts shape memory properties to the polymer.

[0190] Figure 3B is a schematic diagram of the curing process that converts PEVA polymer into covalently crosslinked PEVA. This figure shows various sites within the PEVA polymer where covalent crosslinking is likely to occur upon exposure to the initiator and crosslinker. This figure shows the structural changes at the molecular level in detail, and by highlighting the sites where crosslinking occurs, the mechanical strength and shape memory properties of the polymer are improved.

[0191] Figures 4A and 4B illustrate the shape memory properties of the shape memory textile according to the present invention. Figure 4A shows thermal programming in the laboratory, and Figure 4B shows the ability to reprogram the fibers on the surface of a subject's body due to the heat-shielding properties of the covering yarn and other fabrics constituting the textile.

[0192] <Design Example> The present invention will be described in more detail with reference to the following figures and examples of embodiments, but the present invention is not limited thereto.

[0193] The following table shows some preferred shape memory polymers that constitute the core fibers, with sample ID numbers 1 to 20 representing some preferred examples of the shape memory polymers of the present invention, but not limited to these, each representing a different embodiment of the present invention.

[0194] [Table 3]

[0195] <Example 1: Coated shape memory polymer fiber> In this example, cSMPF was produced according to the method of the present invention. In the first step, the shape memory polymer of the present invention was prepared, and a core fiber precursor was first prepared.

[0196] First, a 50:50 mixture of the initiator and cross-linker, in this case BP and TAIC, is prepared. Next, this mixture is manually mixed with PEVAP (poly[ethylene-co-vinyl acetate]) polymer granules. This manual mixing ensures a preliminary and uniform dispersion of the BP / TAIC mixture and PEVA granules.

[0197] Next, the manually mixed materials are combined in a twin-screw extruder (Euro Prism Lab, Thermo Fisher Scientific, Waltham, USA). The extruder is set to a specific temperature profile: 25°C in the feed zone, then gradually increasing to 80°C, then maintaining 110°C throughout the melting and mixing zones, and finally reaching 100°C at the die. The screw rotation speed is controlled between 30 and 50 rpm, with 50 rpm being preferred. This controlled environment ensures thorough mixing and melting of the components, resulting in a homogeneous mixture.

[0198] After the initial extrusion, the continuous filament is cut into granules. This pelletizing process transforms the extruded mixture into easy-to-handle granules, facilitating subsequent processing and handling.

[0199] The blended granules (PEVAP+BP+TAIC) are then subjected to a second extrusion process. This second extrusion process uses the same temperature profile and screw rotation speed as the first, ensuring consistent and thorough mixing. This repeated extrusion process is essential for achieving uniform dispersion of the crosslinking agent within the polymer matrix. Similar to the first extrusion process, the extruded blend is pelletized again into granules after the second extrusion process.

[0200] Finally, the granules are dried overnight at a temperature of 40°C. This drying step is essential to remove any residual moisture that could negatively affect the subsequent curing process of the polymer.

[0201] The compounded mixture is then fed into a single-screw extruder (Extrudex, Mühlacker, Germany) and extruded. This extruder is equipped with filament dies of various diameters to produce monofilaments of the desired thickness.

[0202] The monofilament is extruded to a diameter of 0.05 mm to 0.5 mm. This diameter range is chosen to balance the mechanical strength and flexibility of the fiber.

[0203] To prevent premature melting of the mixture, the supply zone is maintained at 20°C. The temperature is then increased to 80°C, maintaining a constant temperature of 110°C throughout the melting zone. Finally, the die temperature is set to 100°C. This temperature control profile is crucial for achieving uniform melting and a smooth flow of polymer through the die.

[0204] The screw rotation speed during extrusion is maintained between 5 and 20 rpm. This rotation speed range allows for careful control during the extrusion process, ensuring that the monofilament is extruded at a constant speed and with a uniform diameter.

[0205] Polymers contained in the core fibers or their blends can be crosslinked by covalent bonds, ionic interactions, or microcrystalline structures.

[0206] The shape-memory polymer fibers were cured by in-line UV irradiation, integrated with the fiber extrusion process. This method streamlines the manufacturing process by allowing for immediate crosslinking while the fibers are being produced.

[0207] The gel content of covalently crosslinked polymer networks is 60–100% according to ASTM D2765 or ISO 10147. The gel content (G) of crosslinked core fibers, more specifically, of crosslinked shape memory polymers composed of core fibers, was evaluated by extraction using a solvent such as toluene or xylene at a constant temperature of ≤110°C. The extraction time was 24 hours, after which the solvent was evaporated in a vacuum oven at 45°C for another 24 hours. G is the isolated weight m of the sample. iso And, the dry weight after extraction m d Therefore, it was calculated using the following formula.

number

[0208] However, unextracted fibers were used for the coating and for investigating thermomechanical properties and shape memory properties. Table 3 shows the results of gel content measurements for various exemplary shape memory polymers in line with the spirit of the present invention.

[0209] In this particular embodiment, the selected shape memory polymer, comprising the core fiber (10), was PEVA. Semicrystalline crosslinked poly[ethylene-co-vinyl acetate] (cPEVA) fibers were coated in single or double layers with yarn twisted 750 to 3000 times per meter. The number of twists allowed for a certain degree of deformation while maximizing the engineering strain (ε) of the core shape memory polymer fiber. max ) the strain (ε) at the yield point of the uncoated core fibers yield The level was adjusted to be reduced to below ).

[0210] The effects of the twist density and twist angle of the coated yarn on the programming and recovery elasticity of the SMP coated yarn were evaluated.

[0211] In this exemplary embodiment, the mechanical properties of coated and uncoated shape memory polymer fibers were tested by tensile tests at room temperature and high temperatures (below and within the broad melt transition temperature range). These tensile tests were performed using a Zwick / Roell Z005 testing machine (Zwick, Ulm, Germany) equipped with a thermochamber and temperature controller (Eurotherm Regler, Limburg, Germany) at a strain rate of 5 mm·min. -1 The measurements were conducted at the following temperatures: 25°C, 37°C, 40°C, 50°C, 60°C, 70°C, 80°C, and 90°C.

[0212] Several properties were measured for exemplary coated shape memory polymer fibers (cSMPF) SMP-1 to SMP-8, SMP-10, SMP-17 to SMP-20 (Table 3) according to this particular embodiment. The modulus of elasticity (E) (at 25°C) ranged from 2.49 ± 0.1 to 9.07 ± 0.3 MPa, and the elongation at break (ε) was measured. break ) and stress at fracture (σ break The following was obtained and analyzed: Elongation at fracture (ε break The range of ) was measured from 730±130% to 915±20%. The shape recovery rate in these specific examples (after normal stretching to 50%) was measured from 97% to 100%. Yield strain (ε) at 25°C yield The range was determined to be between 24±0.2% and 54±0.5%.

[0213] Similarly, the shape memory properties of the fibers were evaluated using a Zwick / Roell Z005 machine (Zwick, Ulm, Germany) equipped with a thermochamber and temperature controller (Eurotherm Regler, Limburg, Germany). Each shape memory cycle in a single experiment consisted of an initial programming step followed by heating and cooling rates ≤10°C·min. -1 The test consisted of a recovery step under stress-free conditions. Each shape memory test consisted of at least 3 cycles. A single-step programming procedure was applied, and the sample was programmed at a temperature (T prog ) and ≤10mm·min -1at a speed to a specific programming strain (ε prog ), then followed by an equilibrium time of ≤ 10 minutes and cooled to below the crystallization temperature (≤ 25°C) under a constant strain. Further, after an equilibrium time of ≤ 10 minutes, at this low temperature, the stress was released and the sample was reheated to the recovery temperature (T rec ). During the recovery cycle, a constant force of ≤ 0.1 N was applied to the test piece. T rec can be anywhere within the melting point range of the polymer and can also be the same as T prog . The shape fixation rate and the recovery rate were calculated from the second and third cycles, and the results were analyzed. The shape recovery rate of the coated fiber was ≥ 95%.

[0214] To ensure and evaluate the long-term shape memory ability of these fibers, a shape memory cycle test of about 100 times was carried out. As a result, throughout 100 cycles, the shape recovery rate and the decrease in the shape fixation rate were the same. For practical reasons and to shorten the time of one cycle, here, the heating rate and the cooling rate were set to 10 °C·min -1 , and the equilibration time was shortened to 1 minute.

[0215] The above are only some preferred realizable embodiments of the present invention. Therefore, all equivalent structural changes made by applying the description of the present invention shall be included in the scope of this patent application.

[0216] The present invention has been described and illustrated with reference to specific embodiments, but the present invention is not limited to these embodiments. Those skilled in the art will understand that various modifications and alterations can be made without departing from the true scope of the present invention defined by the claims and the specification. Therefore, all modifications and alterations within the scope of the appended claims and their equivalents shall be included in the scope of the present invention.

[0217] <Example 2: Shape Memory Textile> In this particular example of the present invention, thermal programming of a shape-memory textile incorporating coated shape-memory polymer fibers is demonstrated using coated PEVA fibers. These fibers were first programmed individually before being incorporated into the textile. Exemplary textiles are shown in Figures 4A and 4B.

[0218] The programming process involves heating the shape-memory textile to 60°C, stretching it to a low programming strain of 50%, and then cooling it to approximately 25°C. This step establishes the temporary shape of the shape-memory polymer fibers contained within.

[0219] This example demonstrates a specific instance of the broader applicability of the technology disclosed herein by incorporating thermally programmed, coated shape-memory polymer fibers into a knitted cotton textile through weaving. Initially, these fibers were incorporated into a knitted textile with a diameter of 14 cm. Upon exposure to a temperature of 60°C, the textile shrunk significantly, reducing its diameter from 14 cm to 10 cm. This change was caused by the activation of the shape recovery process in the SMP fibers within the coated shape-memory polymer fibers.

[0220] To demonstrate the versatility of this method, a reprogramming step was applied to the shape-memory textile. In this process, the textile was reheated to 60°C, manually expanded to its original diameter of 14 cm, and then cooled to 25°C. This procedure reset the coated shape-memory polymer fibers to a new shape, which was temporarily held. Upon reheating to 60°C, the textile consistently returned to a diameter of 10 cm. This reprogramming and recovery cycle was successfully repeated five times, highlighting the durability and reliability of the shape-memory effect in the textile.

[0221] A key feature of this example is the thermal insulation of the cotton component of the textile. This insulation allows the SMP fibers to be safely heated and reshaped, maintaining safety even during wear. Notably, taking PEVA fibers as an example, the initial programming of the shape-changing fibers was performed before they were incorporated into the textile, whereas subsequent cycles involved reprogramming of the entire textile, including the integrated SMP fibers. This highlights the flexibility of the programming process, which is effective for both individual coated shape-memory polymer fibers and composite shape-memory textiles containing them. Furthermore, this demonstrates that the textiles employed are thermally programmable in order to directly fit and conform to the subject's body.

[0222] This example highlights the innovative potential of thermally programmable shape-memory textiles to create dynamic and highly adaptable fabrics. This opens up possibilities for applications in various fields, such as adjustable clothing or medical textiles. In these applications, the ability of the textile to adapt to changing shapes is leveraged to provide a definable and reprogrammable pressure directly related to programmed strain. [Explanation of Symbols]

[0223] (1) Coated shape memory polymer fibers (cSMPF) (10) Core fibers (20) Non-stretchable coated yarn (30) Semicrystalline shape memory polymer (31) Crystalline rigid segment (32) Switching segment (40) Covalently crosslinked shape memory polymer (50) Radical (60) Initiator (61) Cross-linker

Claims

1. A coated shape memory polymer fiber (1) (cSMPF), - A core fiber (10) containing a shape memory polymer (SMP), - A covering yarn (20) having higher tensile rigidity than the core fiber, Includes, A coated shape memory polymer fiber (1), characterized in that the coated yarn (20) is wound around the core fiber (10) such that the maximum engineering strain of the core fiber (10) is reduced to less than or equal to the strain at the yield point of the uncoated core fiber (10).

2. The shape memory polymer is a thermally programmable shape memory polymer, and the programming temperature (T) of the thermally programmable shape memory polymer is measured by differential scanning calorimetry (DSC). ｐｒｏｇ The coated shape memory polymer fiber according to claim 1, wherein the temperature range is 40°C to 80°C.

3. The coated shape memory polymer fiber according to claim 1, wherein the shape memory polymer (SMP) is a semi-crystalline shape memory polymer (SSMP) with a crystallinity of 3% to 70% as measured by wide-angle X-ray scattering (WAXS).

4. The coated shape memory polymer fiber according to claim 3, wherein the semicrystalline shape memory polymer (SSMP) is selected from a list including semicrystalline polyester, ethylene-co-monomer-polymer, di- or multiblock copolymer, or semicrystalline ionomer.

5. The coated shape memory polymer fiber according to claim 1, wherein the core fiber (10) is selected from a shape memory polymer selected from the group consisting of polycaprolactone, poly[ethylene-co-vinyl acetate] (PEVA), poly(ethylene-1-octene), trans-polyoctenomer-containing polycyclooctene (PCO / TOR), poly[ethylene-co-ethyl acrylate-co-maleic anhydride] (PEEAMA), poly[ethylene-co-(methyl acrylate)-co-(glycidyl methacrylate)] (PEMAGMA), perfluorosulfonic acid ionomer (PFSA), and amorphous multiblock alicyclic polyether urethane (PEU) consisting of poly(tetramethylene glycol) (PTMEG), 1,4-butanediol (1,4-BD), and methylenebis(p-cyclohexyl isocyanate) (H12MDI).

6. The shape memory polymer includes poly[ethylene-co-vinyl acetate] (PEVA), the poly[ethylene-co-vinyl acetate] is formed from a poly[ethylene-co-vinyl acetate] polymer (PEVAP), and the vinyl acetate content in the poly[ethylene-co-vinyl acetate] polymer is 5% to 50% of the total weight of the polymer. The coated shape memory polymer fiber according to claim 5.

7. The coated shape memory polymer fiber according to claim 1, wherein the coating yarn (20) is selected from cotton, wool, silk, hemp, viscose, acrylic, nylon, and polyester.

8. The coated shape memory polymer fiber according to claim 1, wherein the elasticity measured using a tensile tester of the coated shape memory polymer fiber is 30 to 1000%.

9. The coated shape memory polymer fiber according to claim 1, wherein the coating yarn (20) is wound around the core fiber (10) at a rate of 500 to 6000 times per meter.

10. The coated shape memory polymer fiber according to claim 1, wherein the core fiber (10) is a multifilament fiber.

11. The coated shape memory polymer fiber according to claim 1, wherein the diameter ratio of the coating yarn to the core fiber is within the range of 1:1 to 1:

20.

12. The coated shape memory polymer fiber according to claim 1, wherein the diameter of the core fiber is within the range of 50 to 500 μm.

13. A method for manufacturing a coated shape memory polymer fiber (cSMPF) according to any one of claims 1 to 12, comprising the following steps: a) Extruding the core fiber (10) of the core fiber precursor for the shape memory polymer according to any one of claims 1 to 5. b) Hardening the extruded fiber, and then c) Winding the coating yarn (20) around the core fiber (10) A method for manufacturing a coated shape memory polymer fiber.

14. A shape memory fabric comprising a coated shape memory polymer fiber (cSMPF) including the core fiber (10) and the coating yarn (20) according to claim 1, wherein the coated shape memory polymer fiber (cSMPF) a) A shape memory mesh network in which cSMPF is woven or intertwined to form a structure that is operably connected, and / or b) A shape memory inlay disposed on a second fabric Placed, A shape memory fabric characterized in that the maximum engineering strain of the core fibers (10) is reduced to less than or equal to the strain at the yield point of the uncoated core fibers (10).

15. A shape memory textile comprising a coated shape memory polymer fiber (cSMPF) as described in claim 1 and at least a further fabric and / or further fibers, wherein the cSMPF is arranged in and / or on the shape memory textile by knitting, weaving, knitting, embroidery, composite techniques, or as a 3D textile structure. A shape memory textile characterized in that the maximum engineering strain of the core fibers (10) is reduced to less than or equal to the strain at the yield point of the uncoated core fibers (10).

16. A method for manufacturing the shape memory fabric and / or the shape memory textile according to claim 14 and / or claim 15, comprising the following steps: a) A step of preparing a coated shape memory polymer fiber (cSMPF) according to any one of claims 1 to 12, then, b) The process of placing the coated shape memory polymer fiber (cSMPF) in and / or on a textile or fabric. A method for manufacturing shape-memory fabrics and / or shape-memory textiles, including the following.

17. Use of coated shape-memory polymer fibers according to any one of claims 1 to 12 for compression garments, orthopedic bandages, braces, posture-correcting garments, push-up garments, corsets and corsages, and sportswear.

18. A thermally programmable textile comprising a coated shape-memory polymer fiber as described in claim 1, or a shape-memory fabric as described in claim 14, or a shape-memory textile as described in claim 15.

19. Use of the thermally programmable textile according to claim 18 as a medical or orthopedic garment.

20. Use of the thermally programmable textile according to claim 18 as sports or leisure clothing.

21. A thermally programmable fabric comprising a coated shape-memory polymer fiber as described in claim 1, or a shape-memory fabric as described in claim 14, or a shape-memory textile as described in claim 15.

22. Use of the thermally programmable fabric according to claim 21 as a medical or orthopedic garment.

23. Use of the thermally programmable fabric according to claim 21 as sports or leisure clothing.

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