Low temperature thermoplastic sheet, radiotherapy positioning film and rehabilitation external fixator

Abstract

The present application relates to the technical field of medical devices, in particular to a low-temperature thermoplastic plate, a radiotherapy positioning film and a rehabilitation external fixation brace, comprising a plurality of elastic layers and a plurality of base layers, the elastic layers serving as the upper and lower surface layers of the low-temperature thermoplastic plate, the base layers being non-crosslinked layer structures, and the base layers being hot-pressed and attached between two adjacent elastic layers. The radiotherapy positioning film and the rehabilitation external fixation brace are both made of the above low-temperature thermoplastic plate. In the present application, the elastic layers serve as the surface layers of the low-temperature thermoplastic plate, and the surface layers lose surface tackiness without coating treatment, thus simplifying the production process flow. The arrangement of the plurality of base layers and the plurality of elastic layers not only reduces the problem of shear delamination between the elastic layers and the base layers, but also enables the inner layers of the low-temperature thermoplastic plate to have similar mechanical properties to the surface layers, so that the inner and outer layers of the product can deform and recover synchronously, and the base layers have the shape memory feature without crosslinking.

Description

Technical Field

[0001] This invention relates to the technical field of medical devices, and in particular to a low-temperature thermoplastic plate, a radiotherapy positioning membrane, and a rehabilitation external fixation brace. Background Technology

[0002] The main raw material of low-temperature thermoplastic sheets commonly used for positioning in radiotherapy and external fixation in orthopedic rehabilitation is polycaprolactone. Its characteristic is that it softens when heated to around 65°C and can be molded into any shape, while retaining suitable support strength after cooling to room temperature. Based on this characteristic, this material can be used for precise positioning of cancer patients during radiotherapy and for fixation of the limbs or trunk during rehabilitation orthopedics. However, polycaprolactone has low melt strength. If the sheets are not cross-linked, their stretched state after heating will resemble dough from ordinary household kneading—while having a certain elongation at break, the thickness of the stretched portion is very uneven. Low-temperature thermoplastic sheets used for radiotherapy fixation need to be stretched by 110-350% during use; if the thickness is uneven, it cannot provide sufficient fixation strength to meet clinical requirements. When low-temperature thermoplastic sheets are used for orthopedic rehabilitation fixation of larger body parts, the low melt strength makes it difficult to remove them from the heating container and shape them for fixation on the patient.

[0003] Currently, the solution to the low melt strength of low-temperature thermoplastic sheets is irradiation crosslinking. Appropriate crosslinking of polycaprolactone materials can impart sufficient melt strength to meet the requirements of uniform elongation of 110-350%, and the ability to properly remove large sheets from the heating container after softening and then reshape and fix them on the patient. Furthermore, crosslinked low-temperature thermoplastic sheets also possess shape memory; if an error occurs during patient fixation, the sheet can recover more than 50% of its deformation upon reheating, meeting the requirements for reshaping. However, irradiation crosslinking has the following drawbacks:

[0004] First, the accuracy of the irradiation dose is critical. Too high or too low an irradiation dose will result in the product quality not meeting clinical requirements and making it difficult to control the product quality. Secondly, irradiated cross-linked polycaprolactone materials are more prone to degradation, which places higher demands on the production, transportation and storage of the products. Third, cross-linked polycaprolactone cannot be replasticized, so the scrap material after irradiation cross-linking can only be discarded, resulting in low resource utilization. Fourth, the equipment investment for irradiation crosslinking is large and the environmental protection requirements are high. Low-temperature thermoplastic sheet manufacturers all outsource the irradiation crosslinking to third parties, which not only incurs transportation costs but also prevents continuous production and results in a long production cycle.

[0005] Furthermore, since polycaprolactone has a melting point of 58-60℃, when heated to this temperature, the sheet becomes highly tacky, sticking to everything it touches, making clinical procedures impossible. To solve this tacky problem, a surface coating must be applied to the low-temperature thermoplastic sheet to seal the surface and eliminate its tackiness.

[0006] In summary, the current production process for low-temperature thermoplastic materials is lengthy and involves many steps. It requires third-party irradiation processing, cannot be produced continuously, and the cross-linked scraps cannot be recycled. Summary of the Invention

[0007] Based on this, the purpose of this invention is to overcome the problems of long production process, many steps, need to entrust third-party irradiation processing and cannot be continuously produced, and the inability to recycle the cross-linked edge materials in the existing low-temperature thermoplastic board production process. The invention provides a low-temperature thermoplastic board that does not require irradiation cross-linking treatment and coating treatment, effectively simplifies the production process, enables continuous production, significantly reduces production costs, and allows edge materials to be directly recycled, thus improving resource utilization.

[0008] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A low-temperature thermoplastic sheet includes multiple elastic layers and multiple substrate layers. The elastic layers serve as the upper and lower surface layers of the low-temperature thermoplastic sheet, and the substrate layers have a non-crosslinked structure. The substrate layers are hot-pressed and bonded between two adjacent elastic layers.

[0009] The low-temperature thermoplastic sheet of the present invention includes multiple elastic layers and multiple substrate layers. The substrate layers are hot-pressed and bonded between two adjacent elastic layers, such that: on the one hand, the elastic layers serve as the surface layer of the low-temperature thermoplastic sheet, and on the other hand, an elastic layer is sandwiched between the two substrate layers.

[0010] Using an elastic layer as the surface layer of a low-temperature thermoplastic sheet, with the elastic layer located on both opposite surfaces of the low-temperature thermoplastic sheet, eliminates the need for coating treatment on the surface of the low-temperature thermoplastic sheet, thus simplifying the production process.

[0011] An elastic layer is sandwiched between the two matrix layers, providing support and eliminating the need for cross-linking of the matrix layers. This allows the low-temperature thermoplastic sheet to meet the strength requirements for softening upon heating, removal from the heating container, and shaping on the patient. The multi-layer matrix and elastic layer design not only mitigates the problem of shear delamination between the elastic and matrix layers but also gives the inner layer of the low-temperature thermoplastic sheet similar mechanical properties to the outer layer. This allows the inner and outer layers to deform and recover synchronously, enabling the matrix layer to possess shape memory characteristics without cross-linking. This simplifies the production process, allows for continuous production, and significantly reduces production costs. The scraps from the uncross-linked matrix layer can be directly recycled, improving resource utilization.

[0012] Furthermore, the melting point of the matrix layer is 58℃-60℃, and the elastic layer is elastic within a temperature range of 40℃-80℃. When the matrix layer is shaped, the elastic layer deforms accordingly, and when the elastic layer recovers its deformation, the matrix layer recovers accordingly, meaning that the non-crosslinked matrix layer also possesses shape memory characteristics.

[0013] Furthermore, the matrix layer is a polycaprolactone sheet, and the elastic layer is either an EVA (ethylene-vinyl acetate copolymer) elastic layer or a polyurethane elastic layer. EVA and polyurethane not only have good elasticity but also good compatibility with polycaprolactone, strengthening the interlayer bonding between the elastic layer and the matrix layer and preventing shear delamination between them.

[0014] It should be noted that the material of the matrix layer of the present invention is not limited to polycaprolactone sheets. Other materials with melting points of 58°C-60°C and strengths that meet the requirements of radiotherapy or rehabilitation are also applicable to the present invention. The material of the elastic layer of the present invention is not limited to EVA and polyurethane. Other ester polymers that are elastic and compatible with polycaprolactone are also applicable to the present invention.

[0015] Furthermore, the elastic layer has a plurality of microporous structures, and the matrix layer is at least partially permeated into the microporous structures. For the two outer elastic layers, the microporous structures are specifically closed-cell structures, allowing the matrix to permeate into the microporous structures but not to pass through them. For the inner elastic layer, the microporous structures can be either closed-cell or open-cell structures; when it is an open-cell structure, the matrix can pass through the microporous structures. The microporous structures further improve the bonding ability between the matrix layer and the elastic layer, and further prevent shear delamination between the elastic layer and the matrix layer.

[0016] Furthermore, the elastic layer on the surface of the low-temperature thermoplastic sheet has a portion of its adjacent substrate layer penetrating into the microporous structure; the elastic layer on the inner layer of the low-temperature thermoplastic sheet has a portion of its adjacent substrate layer passing through the microporous structure. The surface elastic layer does not allow the substrate to pass through, so that the surface of the low-temperature thermoplastic sheet loses its surface adhesiveness without coating treatment, simplifying the production process; the inner elastic layer allows the substrate to pass through, which can improve the bonding ability between the substrate layer and the elastic layer, further preventing shear delamination between the elastic layer and the substrate layer.

[0017] Preferably, elastic meltblown fabric is used as the outer elastic layer and elastic sponge is used as the inner elastic layer. The elastic layers of the outer layer can be the same or different, and the matrix layers can be the same or different.

[0018] Preferably, the air permeability of the elastic layer is not less than 500 L / m. 2•s, the elastic layer is one or a combination of EVA sponge and polyurethane elastic meltblown fabric. EVA sponge and polyurethane elastic meltblown fabric not only have elasticity and good compatibility with polycaprolactone, but also have a dense microporous structure. During the heating and shaping process, the matrix layer can penetrate into the microporous structure, thereby further improving the bonding ability between the matrix layer and the elastic layer, and further preventing shear delamination between the elastic layer and the matrix layer.

[0019] Preferably, the elastic elongation of the elastic layer is between 110% and 500%, and the elastic recovery rate of the elastic layer at 110% elongation is not less than 70%. Radiotherapy or rehabilitation treatment requires shaping a planar low-temperature thermoplastic plate into a curved structure that conforms to the human body surface. An elastic elongation of the elastic layer between 110% and 500% can meet the shaping requirements during radiotherapy or rehabilitation treatment. Radiotherapy or rehabilitation treatment is a relatively long process, during which the shape of the affected area and even the patient's body shape will change to some extent. The low-temperature thermoplastic plate possesses shape memory and reshaping capabilities, allowing it to be reshaped and adjusted as the disease progresses.

[0020] Preferably, the tensile stress of the elastic layer at 110% elongation at 50°C is between 15KPa and 250KPa. When using low-temperature thermoplastic materials, to ensure a perfect fit to the contours of the target area, they are generally directly applied to the patient's lesion or injury site for shaping. The force exerted on the material during shaping is directly transmitted to the target area. The tensile stress of the elastic layer at 110% elongation at 50°C is between 15KPa and 250KPa to avoid excessive stress causing discomfort to the patient during treatment.

[0021] Furthermore, the substrate layer is provided with first perforations distributed in a first array, and the first perforations communicate with the microporous structure to form a breathable channel. Since the elastic layer itself already has breathable properties, perforation can be performed only in the substrate layer, without affecting the breathability, and without adversely affecting the tensile properties and shape memory properties of the elastic layer due to perforation.

[0022] Furthermore, a portion of the substrate layer is provided with first perforations distributed in a first array, and a portion of the substrate layer is provided with second perforations distributed in a second array. The first and second perforations are connected to the microporous structure to form a breathable channel. The first and second arrays are different arrays. The low-temperature thermoplastic board has a unique three-dimensional pore structure, which ensures lightweight and breathability while providing better mechanical support and shape memory performance than boards with a single mesh distribution.

[0023] Furthermore, the thickness of the substrate layer is greater than twice the thickness of the elastic layer. The substrate layer is sandwiched between the two elastic layers. During the thermoplastic forming process, the substrate layer penetrates into the elastic layers. The fact that the thickness of the substrate layer is greater than twice the thickness of the elastic layers effectively prevents excessive penetration of the substrate layer from negatively impacting the surface of the low-temperature thermoplastic sheet.

[0024] Preferably, the thickness of the substrate layer is 0.2mm-1mm, and the thickness of the elastic layer is 0.03mm-0.2mm. The thicknesses of both the substrate layer and the elastic layer are the thicknesses of a single substrate layer and a single elastic layer, respectively.

[0025] Furthermore, it also includes a reinforcing structure for local reinforcement of the low-temperature thermoplastic sheet, which gives the low-temperature thermoplastic sheet local rigidity, achieves precise reinforcement of functional zones, and ensures the support strength of key stress-bearing parts.

[0026] Furthermore, a base layer is sandwiched between two elastic layers to form a layer group. The low-temperature thermoplastic board includes two layers, and the two layers are mirror-symmetrical about the reinforcing structure to ensure the overall plasticity and shape memory performance of the low-temperature thermoplastic board.

[0027] Furthermore, the reinforcing structure includes several alternating layers of reinforcing sheets and a reinforcing elastic layer, with the reinforcing sheets serving as the upper and lower surfaces of the reinforcing structure. The matrix layer can be made of polycaprolactone sheets to impart overall shapeability to the low-temperature thermoplastic board. The reinforcing sheets can be designed in shape and selected from low-temperature thermoplastic materials as needed, thereby imparting local rigidity to the low-temperature thermoplastic board and achieving precise reinforcement of functional zones. This ensures the support strength of key stress-bearing parts while retaining the flexibility and fit of non-reinforced areas, significantly expanding the application boundaries of low-temperature thermoplastic materials in personalized medical assistive devices.

[0028] Furthermore, the reinforcing sheet is embedded between the two elastic layers. As a special matrix layer, the reinforcing sheet ensures that the overall low-temperature thermoplastic sheet still consists of alternating elastic and matrix layers, thus making the introduction of the reinforcing sheet almost unaffected by the overall plasticity and shape memory properties of the low-temperature thermoplastic sheet.

[0029] The present invention also provides a radiotherapy positioning membrane, including a positioning frame and a low-temperature thermoplastic plate as described above, wherein the low-temperature thermoplastic plate is connected to the positioning frame and the low-temperature thermoplastic plate is shaped and wrapped around the patient's positioning site.

[0030] The present invention also provides a rehabilitation external fixation brace, including the low-temperature thermoplastic plate as described above, wherein the low-temperature thermoplastic plate is shaped and wrapped around the patient's rehabilitation site.

[0031] Compared with the prior art, the beneficial effects of the present invention are: The low-temperature thermoplastic sheet of the present invention uses an elastic layer as the surface layer of the low-temperature thermoplastic sheet. The elastic layer is located on the two opposite surfaces of the low-temperature thermoplastic sheet, so that the surface of the low-temperature thermoplastic sheet loses its surface adhesiveness without coating treatment, which simplifies the production process.

[0032] The low-temperature thermoplastic board of this invention has an elastic layer sandwiched between two substrate layers. The elastic layer provides support, eliminating the need for cross-linking of the substrate layers. The entire low-temperature thermoplastic board possesses the strength required for heating and softening, removal from the heating container, and shaping on the patient. The multi-layer substrate and multi-layer elastic layer design not only reduces the problem of shear delamination between the elastic and substrate layers but also gives the inner layer of the low-temperature thermoplastic board similar mechanical properties to the surface layer. This allows the inner and outer layers of the product to deform and recover synchronously, enabling the substrate layer to possess shape memory characteristics without cross-linking. This simplifies the production process, allows for continuous production, significantly reduces production costs, and the uncross-linked substrate layer scraps can be directly recycled, improving resource utilization.

[0033] The low-temperature thermoplastic board of the present invention can use polycaprolactone sheet as the base layer to give the low-temperature thermoplastic board overall shapeability. The reinforcing sheet can be designed with shape as needed and selected with a material with a mechanical strength stronger than polycaprolactone as needed, thereby giving the low-temperature thermoplastic board local rigidity and realizing precise reinforcement of functional zones. This ensures the support strength of key stress parts while retaining the flexibility and fit of non-reinforced areas, greatly expanding the application boundaries of low-temperature thermoplastic materials in personalized medical aids. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the low-temperature thermoplastic sheet in Example 1; Figure 2 This is a schematic diagram of the low-temperature thermoplastic sheet in Example 2; Figure 3 This is a schematic diagram of the low-temperature thermoplastic sheet in Example 3; Figure 4 This is a schematic diagram of the low-temperature thermoplastic sheet in Example 4; Figure 5 This is a schematic diagram of the reinforcement structure in Example 4; Figure 6 This is a schematic diagram of the radiotherapy positioning membrane in Example 5; Figure 7 This is a schematic diagram of the external fixation brace for rehabilitation in Example 5; Figure descriptions: 100, Low-temperature thermoplastic sheet; 110, Elastic layer; 111, Microporous structure; 120, Matrix layer; 121, First perforation; 122, Second perforation; 130, Reinforcing structure; 131, Reinforcing sheet; 132, Reinforcing elastic layer; 200, Positioning frame. Detailed Implementation

[0035] The present invention will be further described below with reference to specific embodiments. The accompanying drawings are for illustrative purposes only, representing schematic diagrams rather than actual physical objects, and should not be construed as limiting the scope of this application. To better illustrate the embodiments of the present invention, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0036] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0037] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present application. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0038] Example 1 This embodiment is a first embodiment of a low-temperature thermoplastic sheet 100, including multiple elastic layers 110 and multiple substrate layers 120. The elastic layers 110 serve as the upper and lower surface layers of the low-temperature thermoplastic sheet 100, and the substrate layers 120 have a non-crosslinked layer structure. The substrate layers 120 are hot-pressed and bonded between two adjacent elastic layers 110, such as... Figure 1 As shown.

[0039] Using the elastic layer 110 as the surface layer of the low-temperature thermoplastic sheet 100, with the elastic layer 110 located on both opposite surfaces of the low-temperature thermoplastic sheet 100, eliminates surface tackiness without the need for coating treatment, simplifying the production process. The combination of multiple substrate layers 120 and multiple elastic layers 110 not only mitigates the problem of shear delamination between the elastic layer 110 and the substrate layer 120, but also gives the inner layers of the low-temperature thermoplastic sheet 100 similar mechanical properties to the surface layer. This allows the inner and outer layers of the product to deform and recover synchronously, enabling the substrate layer 120 to possess shape memory characteristics without cross-linking.

[0040] The matrix layer 120 has a melting point of 58℃-60℃, and the elastic layer 110 is elastic within a temperature range of 40℃-80℃. When the matrix layer 120 is shaped, the elastic layer 110 deforms accordingly; when the elastic layer 110 recovers its deformation, the matrix layer 120 also recovers its shape, meaning that the non-crosslinked matrix layer 120 also possesses shape memory characteristics. Specifically, in this embodiment, the matrix layer 120 is a polycaprolactone sheet, and the elastic layer 110 is either an EVA elastic layer or a polyurethane elastic layer.

[0041] In addition, in this embodiment, the elastic layer 110 is provided with a plurality of microporous structures 111, and the matrix layer 120 is at least partially penetrated into the microporous structures 111. Specifically, the elastic layer 110 located on the surface of the low-temperature thermoplastic board 100 has the adjacent matrix layer 120 partially penetrated into the microporous structures 111 but not permeable to the microporous structures 111; the elastic layer 110 located in the inner layer of the low-temperature thermoplastic board 100 has the adjacent matrix layer 120 partially penetrated into the microporous structures 111 but not permeable to the microporous structures 111, thereby further strengthening the interlayer bonding ability between the elastic layer 110 and the matrix layer 120 and preventing shear delamination between the elastic layer 110 and the matrix layer 120. The microporous structures 111 can specifically be closed-cell structures of EVA sponge.

[0042] The thickness of the substrate layer 120 is greater than twice the thickness of the elastic layer 110. Specifically, in this embodiment, the thickness of the substrate layer 120 is 0.2mm-1mm, and the thickness of the elastic layer 110 is 0.03mm-0.2mm. The substrate layer 120 is sandwiched between the two elastic layers 110. During the thermoplastic forming process, the substrate layer 120 will penetrate into the elastic layer 110. The thickness of the substrate layer 120 is greater than twice the thickness of the elastic layer 110, which can effectively avoid the adverse effects of over-penetration of the substrate layer 120 on the surface of the low-temperature thermoplastic sheet 100.

[0043] To improve the breathability and aesthetics of the low-temperature thermoplastic sheet 100, the low-temperature thermoplastic sheet 100 of this embodiment can be perforated as needed. Generally, the perforations are round holes, evenly distributed across the entire surface of the low-temperature thermoplastic sheet 100.

[0044] To illustrate that the low-temperature thermoplastic sheet 100 of this embodiment can simultaneously deform and recover its inner and outer layers during molding and possesses shape memory characteristics, the present invention prepared the following two types of low-temperature thermoplastic sheets 100 and conducted tests: One type of low-temperature thermoplastic sheet 100 includes four elastic layers 110 and three matrix layers 120: the matrix layer 120 is a non-crosslinked polycaprolactone sheet with a thickness of 1 mm; the elastic layer 110 is EVA sponge with a thickness of 0.2 mm, an elastic elongation of 130%, a tensile stress of 15 kPa at 110% elongation under 50°C, and an air permeability of 800 L / m². 2Four elastic layers 110 and three base layers 120 are stacked together in an alternating arrangement and bonded by a hot-pressing process. After cooling and shaping, holes are punched to obtain a low-temperature thermoplastic sheet 100 with a thickness of 3.2 mm. Testing of this low-temperature thermoplastic sheet 100 shows that it can be stretched to more than twice its original length after heating in both the transverse and longitudinal directions, and its shape recovery rate after reheating is greater than 60%. The surface of the low-temperature thermoplastic sheet 100 is not easily sticky after softening, making it suitable for making fixing supports with good plasticity, comfort, breathability, and high support strength.

[0045] Another type of low-temperature thermoplastic board 100 includes eleven elastic layers 110 and ten matrix layers 120: the matrix layer 120 is a non-crosslinked polycaprolactone sheet with a thickness of 0.03 mm; the elastic layer 110 is a polyurethane meltblown fabric with a thickness of 0.03 mm, an elastic elongation of 500%, a tensile stress of 110 kPa at 110% elongation under 50°C, and an air permeability of 1100 L / m². 2 Eleven elastic layers 110 and ten base layers 120 are stacked together in an alternating arrangement and bonded by a hot-pressing process. After cooling and shaping, holes are punched to obtain a low-temperature thermoplastic sheet 100 with a thickness of 2.4 mm. Testing of this low-temperature thermoplastic sheet 100 shows that it can be stretched to more than four times its original length after heating in both the transverse and longitudinal directions, and its shape recovery rate is greater than 70% after reheating. The surface of the low-temperature thermoplastic sheet 100 is not easily sticky after softening, making it suitable for making fixing supports with good plasticity, comfort, breathability, and high support strength.

[0046] Example 2 This embodiment is a second embodiment of the low-temperature thermoplastic sheet 100. This embodiment is similar to the first embodiment, except that the elastic layer 110 on the surface of the low-temperature thermoplastic sheet 100 partially penetrates into the microporous structure 111 adjacent to it; the elastic layer 110 on the inner layer of the low-temperature thermoplastic sheet 100 partially passes through the microporous structure 111 adjacent to it. Figure 2 As shown. The outer elastic layer 110 does not allow the substrate to pass through, so that the surface of the low-temperature thermoplastic sheet 100 loses its surface adhesiveness without coating treatment, simplifying the production process; the inner elastic layer 110 allows the substrate to pass through, which can improve the bonding ability between the substrate layer 120 and the elastic layer 110, and further avoid shear delamination between the elastic layer 110 and the substrate layer 120.

[0047] To verify the excellent performance of the low-temperature thermoplastic sheet 100 in this embodiment, the present invention prepared the following low-temperature thermoplastic sheet 100 and conducted tests: This embodiment is the third embodiment of the low-temperature thermoplastic sheet 100, including four elastic layers 110 and three matrix layers 120: the matrix layer 120 is a non-crosslinked polycaprolactone sheet with a thickness of 1.0 mm; the second and third elastic layers 110 are polyurethane meltblown fabric with a thickness of 0.05 mm, an elastic elongation of 110%, a tensile stress of 50 kPa at 110% elongation under 50°C, and an air permeability of 500 L / m². 2 •s; The first and fourth elastic layers (110) are made of EVA sponge, with a thickness of 0.2mm, an elastic elongation of 130%, a tensile stress of 50Kpa at 110% elongation under 50℃ conditions, and an air permeability of 500L / m³. 2 Four elastic layers 110 and three base layers 120 are stacked together in an alternating arrangement and bonded by a hot-pressing process. After cooling and shaping, holes are punched to obtain a low-temperature thermoplastic sheet 100 with a thickness of 3.2 mm. Testing of this low-temperature thermoplastic sheet 100 shows that it can be stretched to more than four times its original length after heating in both the transverse and longitudinal directions, and its shape recovery rate is greater than 70% after reheating. The surface of the low-temperature thermoplastic sheet 100 is not easily sticky after softening, making it suitable for making fixing supports with good plasticity, comfort, breathability, and high support strength.

[0048] Example 3 This embodiment is the third embodiment of the low-temperature thermoplastic board 100. This embodiment is similar to the first embodiment, except that the substrate layer 120 is punched in this embodiment, and the punched substrate layer 120 and elastic layer 110 are hot-pressed together. This punching method can ensure good air permeability of the product on the one hand, and avoid the adverse effects of punching the elastic layer 110 on the tensile properties and shape memory properties of the elastic layer 110.

[0049] In one embodiment, the substrate layer 120 is provided with first perforations 121 distributed in a first array, and the first perforations 121 communicate with the microporous structure 111 to form a breathable channel. That is, the first perforations 121 on all the substrate layers 120 are distributed in the first array, and all the substrate layers 120 are stacked one on top of the other so that the first perforations 121 overlap on the same projection plane.

[0050] In another embodiment, a portion of the substrate layer 120 is provided with first perforations 121 arranged in a first array, and a portion of the substrate layer 120 is provided with second perforations 122 arranged in a second array. The first perforations 121 and the second perforations 122 communicate with the microporous structure 111 to form air-permeable channels. Figure 3 As shown. The first and second arrays are different arrays. The low-temperature thermoplastic board 100 has a unique three-dimensional hole structure, which ensures that it is lightweight and breathable while having better mechanical support and shape memory performance than boards with a single mesh distribution.

[0051] As a preferred option, taking the three-layer matrix layer 120 as an example: Using three layers of 1.0mm non-crosslinked polycaprolactone low-temperature thermoplastic sheet as the base layer 120, referred to as the first base layer, second base layer, and third base layer, two layers with a thickness of 0.05mm and an elongation of 110%, the tensile stress at 110% elongation at 50℃ is 50kPa, and the air permeability is 500L / m. 2 The polyurethane meltblown fabric with a density of 30 g / cm³ is designated as the first elastic layer, and two layers of polyurethane meltblown fabric with a density of 30 g / cm³ are also included. 3 An EVA sponge with an elastic elongation of 130% and a thickness of 0.2mm is called elastic layer 110, and is referred to as the second elastic layer.

[0052] First, the first, second, and third substrate layers are punched. The first and third substrate layers have diamond-shaped holes with a diameter of 1.7 mm and a spacing of 2 mm. The second substrate layer has square-shaped holes with a diameter of 1.5 mm and a spacing of 2 mm. These layers are stacked in the following order: second elastic layer - first substrate layer - first elastic layer - second substrate layer - first elastic layer - first substrate layer - second elastic layer. They are then bonded together using a hot-pressing process to produce a 3.2 mm thick low-temperature thermoplastic sheet 100. This thermoplastic sheet has a unique three-dimensional hole structure, ensuring lightweight breathability while providing better mechanical support than sheets with a single mesh distribution.

[0053] Example 4 This embodiment is the fourth embodiment of the low-temperature thermoplastic board 100. This embodiment is similar to the first embodiment, except that it also includes a reinforcing structure 130 for local reinforcement of the low-temperature thermoplastic board 100.

[0054] A matrix layer 120 is sandwiched between two elastic layers 110 to form a layer group. The low-temperature thermoplastic sheet 100 includes two layer groups, and the two layer groups are mirror-symmetrical about the reinforcing structure 130. The matrix layer 120 and the elastic layer 110 serve as the main structure of the low-temperature thermoplastic sheet 100. Each layer group is a sandwich structure, and the mirror symmetry of the layer groups about the reinforcing structure 130 can ensure the tensile plasticity and shape memory properties of the low-temperature thermoplastic sheet 100.

[0055] Specifically, the reinforcing structure 130 includes a plurality of alternately laid reinforcing sheets 131 and reinforcing elastic layers 132, wherein the reinforcing sheets 131 serve as the upper and lower surface layers of the reinforcing structure 130, such as Figure 4-5As shown. In this embodiment, a low-temperature thermoplastic material sheet can be used as the reinforcing layer 131. The low-temperature thermoplastic material is a material with a melting point of 55℃-65℃. This reinforcing layer 131 can serve as a special matrix layer 120. In this way, on the one hand, a good reinforcing effect can be ensured, and on the other hand, the longitudinal section of the low-temperature thermoplastic board 100 still has an elastic layer 110 located on the surface layer of the low-temperature thermoplastic board 100, and the middle part has two matrix layers 120 sandwiching an elastic layer 110. Thus, the introduction of the reinforcing structure 130 hardly affects the overall plasticity and shape memory properties of the low-temperature thermoplastic board 100.

[0056] For this type of low-temperature thermoplastic board 100 with different shapes of each layer structure, the position limitation of the base layer 120 hot-pressed and bonded between two adjacent elastic layers 110 refers to the relative position limitation of the layer structure shown in the longitudinal section containing all layers.

[0057] To verify the excellent performance of the low-temperature thermoplastic sheet 100 in this embodiment, the present invention prepared the following low-temperature thermoplastic sheet 100 and conducted tests: Using two 2mm thick layers of non-crosslinked polycaprolactone low-temperature thermoplastic board 100 as the base layer 120, with a four-layer thickness of 0.03mm, an elongation of 120%, a tensile stress of 250KPa at 110% elongation under 50℃, and an air permeability of 500L / m², the material is designed for use. 2 Polyurethane elastic meltblown fabric of type s is used as elastic layer 110. Three layers of reinforcing sheets of a specific shape and a thickness of 0.2 mm are used as reinforcing sheet layer 131. Two layers of 0.1 mm thick EVA sponge of the same shape as reinforcing sheet layer 131 are used as reinforcing elastic layer 132. The reinforcing elastic layer 132 and reinforcing sheet layer 131 are stacked on specific parts of the base layer 120 and elastic layer 110 in the following order: elastic layer 110-base layer 120-base layer 120-base layer 110. The reinforcing elastic layer 132 and reinforcing sheet layer 131 are stacked on specific parts of the base layer 120 and elastic layer 110. Then, they are hot-pressed together to form a locally reinforced low-temperature thermoplastic board 100. While maintaining the good plasticity of ordinary low-temperature thermoplastic sheet 100, the bending strength of the locally reinforced area is increased by 120% compared with the ordinary area, making it suitable for custom-made fixtures with different mechanical performance requirements in different parts.

[0058] Example 5 This embodiment is an example of a radiotherapy positioning membrane, including a positioning frame and a low-temperature thermoplastic plate 100 as described in any one of embodiments one to four. The low-temperature thermoplastic plate 100 is connected to the positioning frame 200 and is shaped and wrapped around the patient's positioning site.

[0059] Example 6 This embodiment is an example of a rehabilitation external fixation brace, including the low-temperature thermoplastic plate 100 from any of the embodiments one to four, which is shaped and wrapped around the patient's rehabilitation area.

[0060] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A low-temperature thermoplastic sheet (100), characterized in that, It includes multiple elastic layers (110) and multiple substrate layers (120). The elastic layers (110) serve as the upper and lower surfaces of the low-temperature thermoplastic sheet (100). The substrate layers (120) have a non-crosslinked layer structure and are hot-pressed together between two adjacent elastic layers (110).

2. The low-temperature thermoplastic sheet (100) according to claim 1, characterized in that, The base layer (120) has a melting point of 58°C-60°C, and the elastic layer (110) is elastic in the temperature range of 40°C-80°C.

3. The low-temperature thermoplastic sheet (100) according to claim 2, characterized in that, The substrate layer (120) is a polycaprolactone sheet, and the elastic layer (110) is either an EVA elastic layer or a polyurethane elastic layer.

4. The low-temperature thermoplastic sheet (100) according to claim 3, characterized in that, The elastic layer (110) is provided with a plurality of microporous structures (111), and the matrix layer (120) is at least partially penetrated into the microporous structures (111).

5. The low-temperature thermoplastic sheet (100) according to claim 4, characterized in that, The elastic layer (110) located on the surface of the low-temperature thermoplastic board (100) has a portion of the adjacent substrate layer (120) penetrating into the microporous structure (111); the elastic layer (110) located in the inner layer of the low-temperature thermoplastic board (100) has a portion of the adjacent substrate layer (120) passing through the microporous structure (111).

6. The low-temperature thermoplastic sheet (100) according to claim 4, characterized in that, The substrate layer (120) is provided with first perforations (121) distributed in a first array, and the first perforations (121) are connected to the microporous structure (111) to form a breathable channel.

7. The low-temperature thermoplastic sheet (100) according to claim 6, characterized in that, Part of the substrate layer (120) is provided with first perforations (121) arranged in a first array, and part of the substrate layer (120) is provided with second perforations (122) arranged in a second array. The first perforations (121) and the second perforations (122) are connected to the microporous structure (111) to form a breathable channel.

8. The low-temperature thermoplastic sheet (100) according to claim 1, characterized in that, The thickness of the substrate layer (120) is more than twice the thickness of the elastic layer (110).

9. A low-temperature thermoplastic sheet (100) according to claim 8, characterized in that, The thickness of the substrate layer (120) is 0.2mm-1mm, and the thickness of the elastic layer (110) is 0.03mm-0.2mm.

10. The low-temperature thermoplastic sheet (100) according to any one of claims 1 to 9, characterized in that, It also includes a reinforcement structure (130) for local reinforcement of the low-temperature thermoplastic sheet (100).

11. The low-temperature thermoplastic sheet (100) according to claim 10, characterized in that, A base layer (120) is sandwiched between two elastic layers (110) to form a layer group. The low-temperature thermoplastic board (100) includes two layers, and the two layers are mirror-symmetrical about the reinforcing structure (130).

12. The low-temperature thermoplastic sheet (100) according to claim 11, characterized in that, The reinforcing structure (130) includes a plurality of alternatingly laid reinforcing sheets (131) and reinforcing elastic layers (132), wherein the reinforcing sheets (131) serve as the upper and lower surfaces of the reinforcing structure (130).

13. A radiotherapy positioning membrane, characterized in that, It includes a positioning frame and a low-temperature thermoplastic plate (100) as described in any one of claims 1 to 12, the low-temperature thermoplastic plate (100) being connected to the positioning frame (200), and the low-temperature thermoplastic plate (100) being molded and wrapped around the patient's positioning area.

14. A rehabilitation external fixation brace, characterized in that, Includes a low-temperature thermoplastic plate (100) as described in any one of claims 1 to 12, wherein the low-temperature thermoplastic plate (100) is shaped and wrapped around the patient's rehabilitation area.

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