A 3D printable smart self-adaptive adhesive film, and a preparation method and application thereof

Abstract

The application relates to the field of adhesive stickers, and discloses a 3D-printable intelligent self-adaptive adhesive sticker as well as a preparation method and application thereof, which comprises the following steps: dissolving PVA in a DMSO mixed solvent, adding 3,5-dihydroxybenzoic acid, performing esterification reaction under the action of a catalyst sodium bisulfate for 24 hours, performing dialysis purification and freeze-drying drying after the reaction is completed to obtain a PVA-DHBA graft copolymer; dissolving the PVA-DHBA graft copolymer and PVA-SbQ in deionized water or a water / alcohol mixed solvent to form ink which is uniform and has certain viscoelasticity; using an extrusion type or photocuring 3D printer to print the ink into a preset structure; immediately or in the molding process, using a UV light source to irradiate to trigger the crosslinking of the PVA-SbQ, realize the rapid stability of the structure, and obtain the printed structure; the application solves the problems of low biocompatibility, inability to realize wet-state self-adaptability, low safety of photocuring characteristics and low freedom degree of structure manufacturing capacity in the prior art.

Description

Technical Field

[0001] This invention relates to the field of adhesive films, and more particularly to a 3D-printable intelligent adaptive adhesive film, its preparation method, and its application. Background Technology

[0002] In fields such as wearable health monitoring, rehabilitation medicine, soft robotics, and wound repair, there is an urgent need for flexible devices that can provide long-term, stable, and comfortable interfaces on the surfaces of moist and dynamically changing human tissues. Traditional medical tapes or patches have weak adhesion, are prone to causing allergies, have poor breathability, and cannot perfectly conform to irregular body surfaces. Existing electronic skin or biointerface devices often have separate designs for their adhesive layer, functional layer, and base layer, which leads to problems such as interfacial stress mismatch, signal interference, and complex manufacturing processes.

[0003] Limitations of existing technology:

[0004] Adhesion materials: Commercial medical adhesives (such as acrylates) lack biocompatibility and wet adhesion; although mussel biomimetic hydrogels have good adhesion, their mechanical strength and molding precision are often insufficient, making it difficult to construct fine microstructures or embedded functional devices.

[0005] Photopolymerization technology: Most photopolymerization 3D printing materials rely on small molecule photoinitiators, whose residues may cause cytotoxicity and allergic reactions, limiting their safety in long-term implantation or skin contact applications.

[0006] Manufacturing and Integration Technologies: Traditional manufacturing methods (such as etching and transfer printing) struggle to achieve personalized customization of film structures (such as porosity, thickness, and pattern) and integrated molding of functional components (such as electrodes and piezoelectric elements). Mismatches in the mechanical properties of devices and tissues can lead to discomfort, signal drift, or failure.

[0007] Therefore, it is necessary to develop a new material system that combines excellent biocompatibility, wet adaptive adhesion, safe photocuring properties, and high degree of freedom in structural manufacturing, in order to achieve a smart film that can be seamlessly integrated with the tissue interface and has customizable functions. Summary of the Invention

[0008] The present invention aims to provide a 3D printable intelligent adaptive adhesive film, its preparation method and application, to solve the problems of low biocompatibility, inability to achieve wet adaptive adhesion, low safety of photocuring characteristics and low degree of freedom in structural manufacturing in the prior art.

[0009] To achieve the above objectives, the present invention provides the following method:

[0010] The present invention provides a method for preparing a 3D-printable intelligent adaptive adhesive film:

[0011] S1: Synthesis of PVA-DHBA graft copolymer: PVA was dissolved in a DMSO mixed solvent, and 3,5-dihydroxybenzoic acid was added. The molar ratio of PVA to 3,5-dihydroxybenzoic acid was 6:1 to 1:1. Under the action of sodium bisulfate catalyst, the esterification reaction was carried out at 80°C for 24 hours in an inert gas atmosphere. After the reaction, the product was purified by dialysis for 5 days and then lyophilized for 3 days to obtain the PVA-DHBA graft copolymer.

[0012] S2: Preparation of 3D printing photosensitive ink: Dissolve the PVA-DHBA graft copolymer and PVA-SbQ together in deionized water or water / alcohol mixed solvent at a mass ratio of 10:1 to 2:1 to form a homogeneous ink with a certain degree of viscoelasticity.

[0013] S3: 3D printing and photopolymerization: Using an extrusion or photopolymerization 3D printer, the ink is printed into a preset structure. After printing, an ultraviolet light source is used immediately or during the forming process to trigger the cross-linking of the PVA-SbQ, thereby achieving rapid and stable structure and obtaining the printed structure.

[0014] S4: Post-processing and functionalization: The functional element is placed in the predetermined position of the printed structure, or an active substance is loaded on the surface of the printed structure by coating or impregnation, and then secondary cross-linking or encapsulation is performed.

[0015] Preferably, the inert gas is nitrogen, argon, or helium.

[0016] Preferably, the alcohol in the water / alcohol mixed solvent is ethanol, propanol, or isopropanol.

[0017] Preferably, the viscosity of the ink is between 500 mPa·s and 5000 mPa·s.

[0018] Preferably, the preset structure is a thin film, a mesh, a structure with grooves, or a structure with cavities.

[0019] Preferably, the wavelength of the ultraviolet light source is 365nm.

[0020] Preferably, the functional element is a microsensor or a piezoelectric element.

[0021] Preferably, the secondary crosslinking method is ultraviolet light irradiation crosslinking, and the irradiation time is 1 minute to 15 minutes.

[0022] The present invention provides a 3D-printable intelligent adaptive adhesive film prepared according to the preparation method of a 3D-printable intelligent adaptive adhesive film described above.

[0023] The present invention provides the application of a 3D-printable intelligent adaptive adhesive film as described above in the fields of smart wearable devices, electronic device packaging, and medical dressings.

[0024] The beneficial effects of this invention are reflected in:

[0025] 1. Adaptive Wet Adhesion and Tissue Conformity: The catechol groups in the PVA-DHBA graft copolymer endow the material with strong wet adhesion capabilities similar to mussel byssal silk. This film can closely adhere to the surface of moist, irregular, and dynamically changing skin or soft tissue, forming a low-modulus, highly compliant interface, significantly reducing discomfort and signal noise caused by mechanical mismatch.

[0026] 2. Safe and efficient photocuring: PVA-SbQ is a classic photocrosslinking polymer. Its SbQ groups can undergo a dimerization reaction under ultraviolet light without the need for small molecule photoinitiators, fundamentally eliminating the potential biotoxicity risks of photoinitiators and their decomposition products. Through physical blending with PVA-DHBA, safe photocuring of the entire ink system is achieved.

[0027] 3. 3D printing provides the freedom to design integrated structures and functions.

[0028] 4. Customized Structure: The macroscopic shape, thickness, and pore structure of the film can be precisely controlled through 3D printing (such as biomimetic honeycomb structure to improve breathability), perfectly adapting to specific anatomical parts (such as joints and face).

[0029] 5. Functional integration: As an "integrated platform", functional modules can be directly embedded / integrated during or after printing.

[0030] 6. Sensing Interface: The printed adhesive layer serves as an ideal interface between the flexible electrode, strain sensor, and skin, ensuring stable contact without affecting sensing sensitivity.

[0031] 7. Treatment platform: It can be loaded with or combined with piezoelectric materials (such as PZT nanofibers, PVDF), and utilizes the deformation of the film with tissue movement to generate a piezoelectric effect, so as to realize electrical stimulation to promote wound healing or analgesia.

[0032] 8. Drug delivery: Porous structures can be used for loading and controlled release of drugs.

[0033] 9. Excellent biocompatibility and mechanical compatibility: Based on PVA, the material itself has good biocompatibility. By adjusting the ratio of PVA-DHBA to PVA-SbQ and the printing parameters, the mechanical properties (modulus, toughness) of the resulting film can be flexibly controlled to match soft tissue (~kPa-MPa). Attached Figure Description

[0034] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0035] Figure 1 The following diagrams are provided for embodiments of the present invention: a) a schematic diagram of the material tightly bonded to pigskin; b) a schematic diagram of the photocuring properties of the material; c) a schematic diagram of the material bonding to glass and plastic interfaces.

[0036] Figure 2 The synthesis variation diagram of the NMR results verification material and the schematic diagram of the tensile properties of the intelligent adaptive adhesive film are provided for the embodiments of the present invention.

[0037] Figure 3 a) A schematic diagram of the 3D printing process of the intelligent adaptive adhesive film provided in an embodiment of the present invention;

[0038] Figure 4 An adaptive schematic diagram of the material and finger joint and a schematic diagram of the mechanical strength of the 3D-printed thin film product provided for embodiments of the present invention;

[0039] Figure 5 This is a schematic diagram of the intelligent adaptive adhesive film bonding to the heart, liver, spleen, lungs, and kidneys provided in an embodiment of the present invention;

[0040] Figure 6 The diagrams provided in this invention are: a schematic diagram of the intelligent adaptive adhesive film bonded to tissue after being subjected to water flow erosion, and a schematic diagram of the overlap shear adhesion test between the intelligent adaptive adhesive film and plastic, glass, bone fragments, mucous membranes, and skin. Detailed Implementation

[0041] To enable those skilled in the art to better understand the present invention, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, apparatus, product, or end that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products, or ends.

[0043] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0044] Limitations of existing technology:

[0045] Adhesion materials: Commercial medical adhesives (such as acrylates) lack biocompatibility and wet adhesion; although mussel biomimetic hydrogels have good adhesion, their mechanical strength and molding precision are often insufficient, making it difficult to construct fine microstructures or embedded functional devices.

[0046] Photopolymerization technology: Most photopolymerization 3D printing materials rely on small molecule photoinitiators, whose residues may cause cytotoxicity and allergic reactions, limiting their safety in long-term implantation or skin contact applications.

[0047] Manufacturing and Integration Technologies: Traditional manufacturing methods (such as etching and transfer printing) struggle to achieve personalized customization of film structures (such as porosity, thickness, and pattern) and integrated molding of functional components (such as electrodes and piezoelectric elements). Mismatches in the mechanical properties of devices and tissues can lead to discomfort, signal drift, or failure.

[0048] Therefore, it is necessary to develop a new material system that combines excellent biocompatibility, wet adaptive adhesion, safe photocuring properties, and high degree of freedom in structural manufacturing, in order to achieve a smart film that can be seamlessly integrated with the tissue interface and has customizable functions.

[0049] The present invention aims to provide a 3D printable intelligent adaptive adhesive film, its preparation method and application, to solve the problems of low biocompatibility, inability to achieve wet adaptive adhesion, low safety of photocuring characteristics and low degree of freedom in structural manufacturing in the prior art.

[0050] This invention provides a method for preparing a 3D-printable intelligent adaptive adhesive film, comprising the following steps:

[0051] S1: Synthesis of PVA-DHBA graft copolymer: PVA was dissolved in a DMSO mixed solvent, and 3,5-dihydroxybenzoic acid was added. The molar ratio of PVA to 3,5-dihydroxybenzoic acid was 6:1 to 1:1. Under the action of sodium bisulfate catalyst, the esterification reaction was carried out at 80°C for 24 hours in an inert gas atmosphere. The inert gas was nitrogen, argon or helium. After the reaction was completed, the product was purified by dialysis for 5 days and lyophilized for 3 days to obtain the PVA-DHBA graft copolymer.

[0052] S2: Preparation of 3D printing photosensitive ink: PVA-DHBA graft copolymer and PVA-SbQ are dissolved together in deionized water or water / alcohol mixed solvent at a mass ratio of 10:1 to 2:1 to form a homogeneous ink with certain viscoelasticity. The alcohol in the water / alcohol mixed solvent is ethanol, propanol or isopropanol, and the viscosity of the ink is 500 mPa·s to 5000 mPa·s.

[0053] S3: 3D Printing and Photopolymerization: Using an extrusion or photopolymerization 3D printer, ink is printed into a preset structure, which can be a thin film, a mesh, a grooved structure, or a cavity structure. After printing, an ultraviolet light source is used to irradiate the structure immediately or during the forming process. The wavelength of the ultraviolet light source is 365nm, which triggers the cross-linking of PVA-SbQ, achieving rapid stabilization of the structure and obtaining the printed structure.

[0054] S4: Post-processing and functionalization: The functional element is placed in the predetermined position of the printed structure. The functional element is a micro-sensor or a piezoelectric sheet, or an active material is loaded on the surface of the printed structure by coating or impregnation, and then a secondary cross-linking or encapsulation is performed. The secondary cross-linking method is ultraviolet light irradiation cross-linking, and the irradiation time is 1 to 15 minutes.

[0055] The present invention provides a 3D-printable intelligent adaptive adhesive film prepared according to the preparation method of a 3D-printable intelligent adaptive adhesive film described above.

[0056] The present invention provides the application of a 3D-printable intelligent adaptive adhesive film as described above in the fields of smart wearable devices, electronic device packaging, and medical dressings.

[0057] like Figure 1 As shown, the material's adhesive properties and photocuring performance are as follows:

[0058] a. The material is tightly bonded to the pigskin and can withstand the pulling, bending and twisting of the pigskin;

[0059] b. The photocurability of the material;

[0060] c. The material can bond to various interfaces, including glass, plastic and other surfaces;

[0061] like Figure 2 As shown, the material's synthesis and mechanical properties

[0062] The NMR results showed that the synthesis of inflammatory materials peaked at 6-7 ppm;

[0063] The material's tensile properties allow it to reach a force of 500 kPa at 500% strain;

[0064] Conclusion: The material was successfully synthesized and possesses good mechanical and adhesive properties, enabling it to bond to various interfaces.

[0065] like Figure 3 The 3D printing process of the material is shown below:

[0066] The 3D printing process of materials can be designed and prepared into various shapes, which can be bonded to biological tissues and bear the weight of organs;

[0067] like Figure 4 As shown, the adhesive properties and mechanical strength of the patch

[0068] The material has good self-adaptability to finger joints and conforms to skin folds;

[0069] The 3D-printed film products have good mechanical strength and can withstand a tensile strength of 1 MPa.

[0070] like Figure 5 As shown, the adhesive properties of the material are:

[0071] The material is used to bond tissues such as the heart, liver, spleen, lungs, and kidneys.

[0072] like Figure 6 As shown, the wet bonding properties of the material

[0073] After the material is bonded to the tissue, it can withstand the erosion of water flow, achieving strong wet adhesion;

[0074] The shear bonding test of the material with plastics, glass, bone fragments, mucous membranes, and skin can reach 50 kPa.

[0075] The beneficial effects of this invention are reflected in:

[0076] 1. Adaptive Wet Adhesion and Tissue Conformity: The catechol groups in the PVA-DHBA graft copolymer endow the material with strong wet adhesion capabilities similar to mussel byssal silk. This film can closely adhere to the surface of moist, irregular, and dynamically changing skin or soft tissue, forming a low-modulus, highly compliant interface, significantly reducing discomfort and signal noise caused by mechanical mismatch.

[0077] 2. Safe and efficient photocuring: PVA-SbQ is a classic photocrosslinking polymer. Its SbQ groups can undergo a dimerization reaction under ultraviolet light without the need for small molecule photoinitiators, fundamentally eliminating the potential biotoxicity risks of photoinitiators and their decomposition products. Through physical blending with PVA-DHBA, safe photocuring of the entire ink system is achieved.

[0078] 3. 3D printing provides the freedom to design integrated structures and functions.

[0079] 4. Customized Structure: The macroscopic shape, thickness, and pore structure of the film can be precisely controlled through 3D printing (such as biomimetic honeycomb structure to improve breathability), perfectly adapting to specific anatomical parts (such as joints and face).

[0080] 5. Functional integration: As an "integrated platform", functional modules can be directly embedded / integrated during or after printing.

[0081] 6. Sensing Interface: The printed adhesive layer serves as an ideal interface between the flexible electrode, strain sensor, and skin, ensuring stable contact without affecting sensing sensitivity.

[0082] 7. Treatment platform: It can be loaded with or combined with piezoelectric materials (such as PZT nanofibers, PVDF), and utilizes the deformation of the film with tissue movement to generate a piezoelectric effect, so as to realize electrical stimulation to promote wound healing or analgesia.

[0083] 8. Drug delivery: Porous structures can be used for loading and controlled release of drugs.

[0084] 9. Excellent biocompatibility and mechanical compatibility: Based on PVA, the material itself has good biocompatibility. By adjusting the ratio of PVA-DHBA to PVA-SbQ and the printing parameters, the mechanical properties (modulus, toughness) of the resulting film can be flexibly controlled to match soft tissue (~kPa-MPa).

[0085] The above descriptions are merely embodiments of the present invention. Commonly known technical solutions or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for preparing a 3D-printable intelligent adaptive adhesive film, characterized in that, The method includes: S1: Synthesis of PVA-DHBA graft copolymer: PVA was dissolved in a DMSO mixed solvent, and 3,5-dihydroxybenzoic acid was added. The molar ratio of PVA to 3,5-dihydroxybenzoic acid was 6:1 to 1:

1. Under the action of sodium bisulfate catalyst, the esterification reaction was carried out at 80°C for 24 hours in an inert gas atmosphere. After the reaction, the product was purified by dialysis for 5 days and then lyophilized for 3 days to obtain the PVA-DHBA graft copolymer. S2: Preparation of 3D printing photosensitive ink: Dissolve the PVA-DHBA graft copolymer and PVA-SbQ together in deionized water or water / alcohol mixed solvent at a mass ratio of 10:1 to 2:1 to form a homogeneous ink with a certain degree of viscoelasticity. S3: 3D printing and photopolymerization: Using an extrusion or photopolymerization 3D printer, the ink is printed into a preset structure. After printing, an ultraviolet light source is used immediately or during the forming process to trigger the cross-linking of the PVA-SbQ, thereby achieving rapid and stable structure and obtaining the printed structure. S4: Post-processing and functionalization: The functional element is placed in the predetermined position of the printed structure, or an active substance is loaded on the surface of the printed structure by coating or impregnation, and then secondary cross-linking or encapsulation is performed.

2. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The inert gas is nitrogen, argon, or helium.

3. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The alcohol in the water / alcohol mixed solvent is ethanol, propanol, or isopropanol.

4. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The viscosity of the ink is from 500 mPa·s to 5000 mPa·s.

5. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The preset structure is a thin film, a mesh, a structure with grooves, or a structure with cavities.

6. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The wavelength of the ultraviolet light source is 365nm.

7. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The functional element is a microsensor or a piezoelectric element.

8. The method for preparing a 3D-printable intelligent adaptive adhesive film according to claim 1, characterized in that: The secondary cross-linking method is cross-linking by ultraviolet light irradiation, with an irradiation time of 1 to 15 minutes.

9. A 3D-printable intelligent adaptive adhesive film prepared by the preparation method of a 3D-printable intelligent adaptive adhesive film according to claims 1-8.

10. The application of the 3D-printable smart adaptive adhesive film according to claim 9 in the fields of smart wearable devices, electronic device packaging, and medical dressings.

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