Temperature-triggered reversible adhesive conductive film and preparation method and application thereof

Abstract

The invention relates to a temperature-triggered reversible adhesive conductive film and a preparation method and application thereof, and the preparation method comprises the steps: S1, uniformly mixing a side chain phase transition monomer, a conductive material, an auxiliary material and an initiator according to a ratio to obtain temperature-triggered reversible adhesive conductive film precursor ink; s2, uniformly coating a substrate with the precursor ink prepared in the step S1; and S3, initiating curing of the precursor ink coated on the substrate in the step S2, and stripping from the substrate to obtain the temperature-triggered reversible adhesive conductive film. The property that the modulus of the phase-transition polymer is adjustable at different temperatures is utilized, the phase-transition polymer serves as a film base material and then is mixed with the conductive material and other auxiliary materials, the modulus change is controlled through the temperature, the film cannot adhere in a low-temperature and high-modulus state and can adhere in a high-temperature and low-modulus state, and the film which can adhere as needed and is integrally conductive is achieved; the method has a wide application prospect in the fields of motion monitoring, epidermal sensing, wearable electronics and the like.

Description

Technical Field

[0001] The present invention belongs to the field of flexible electronic technology, and in particular relates to a temperature-triggered reversible adhesive conductive film and a preparation method and application thereof. Background Art

[0002] Flexible electronics plays an important role in medical health, human-computer interaction, wearable devices and other fields and has attracted much attention. In flexible electronics, flexible conductive films are a research hotspot. In addition to good conductivity and sensitivity, the ability to fit closely to the skin and excellent biocompatibility are also essential.

[0003] However, flexible conductive materials still face several challenges. These include the complex manufacturing process required for polymer conductive materials to be composited with other flexible substrates, the poor environmental stability of hydrogel materials, which can easily lose various properties, and the risk of leakage from ionic liquids, which can harm human health. Therefore, developing a conductive film with a simple preparation method, reversible adhesion, and the ability to collect physiological signals is crucial for the research of flexible electronic films.

[0004] The inventor team of this patent application has also been aiming at this goal, and has been committed to the research and development of a conductive film with a simple preparation method, reversible adhesion and the ability to collect physiological signals, and has successively obtained the publication of two patents: Patent 1: Patent No. CN202310329102.7, Patent Name: A flexible conductive film that is easy to peel off and its preparation method. This invention utilizes the property of adjustable modulus of phase change polymer at different temperatures, and uses it as the substrate of the conductive film. By controlling the modulus change by temperature, it can achieve complete transfer of the electrode under low temperature and high modulus conditions; Patent 2: Patent No.: CN202411615284.5, Patent Name: Method for preparing reversibly adhesive flexible conductive film by aerosol jet printing. This invention utilizes the temperature to control the modulus change of phase change polymer, and uses it as the substrate of the conductive film, so that the conductive ink can be completely transferred by aerosol jet printing under low temperature and high modulus conditions to make an adherent and peelable conductive film.

[0005] The conductive films made based on previous research results all use phase change films as the substrate, with conductive materials coated on the surface. The shortcoming is that they are only conductive on one side. In order to facilitate use and expand application scenarios, it is more important to develop a conductive film with a simple preparation method, reversible adhesion, the ability to collect physiological signals, and overall conductivity. Summary of the Invention

[0006] The purpose of the present invention is to overcome the deficiencies of the prior art and to provide a temperature-triggered reversible adhesive conductive film and a preparation method and application thereof.

[0007] The present invention solves the technical problem by the following technical solutions:

[0008] A method for preparing a temperature-triggered reversibly adhesive conductive film, the method comprising the following steps:

[0009] S1. Mixing the side chain phase transition monomer, conductive material, auxiliary material and initiator in proportion to obtain a temperature-triggered reversible adhesion conductive film precursor ink;

[0010] S2, evenly coating the precursor ink prepared in S1 on the substrate;

[0011] S3. The precursor ink coated on the substrate in S2 is cured and peeled off from the substrate to obtain a temperature-triggered reversible adhesive conductive film.

[0012] Moreover, the side chain phase transition monomer is one or more of octadecyl acrylate, hexadecyl acrylate, tetradecyl acrylate, dodecyl acrylate, octadecyl methacrylate, hexadecyl methacrylate, tetradecyl methacrylate, and dodecyl methacrylate.

[0013] Moreover, the conductive material is one or more of a low eutectic solvent, an ionic liquid, a conductive polymer, a metal nanomaterial, a metal powder, MXene, graphene, carbon nanotubes, and carbon powder.

[0014] Moreover, the auxiliary material is a long-chain cross-linking agent or a surfactant; the long-chain cross-linking agent is one or more of Sartomer's CN6021, Sartomer's CN8888, Sartomer's CN9021, Sartomer's CN6290, trimethylolpropane triacrylate, polyurethane diacyl acid, polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and trimethylolpropane trimethacrylate; the surfactant is one or more of Span 80 / sorbitan monooleate, Tween 80 / polyoxyethylene sorbitan monooleate, Span 20 / sorbitan monolaurate, Tween 20 / polyoxyethylene sorbitan monolaurate, sodium lauryl sulfate, and dodecyldimethylammonium oxide.

[0015] Moreover, the mass fraction of the side chain phase transition monomer in the conductive film precursor ink is higher than 30%, the mass fraction of the conductive material is higher than 10%, the mass fraction of the long chain crosslinking agent is not higher than 30%, and the mass fraction of the initiator is not higher than 10%.

[0016] Furthermore, the initiator is a thermal initiator or a photoinitiator.

[0017] Moreover, the material of the substrate is selected from one or more of glass, polystyrene, polyvinyl alcohol, polytetrafluoroethylene, polylactic acid, polyethylene oxide, polyvinyl acetate, polyacrylic acid, polycaprolactone, polyacrylonitrile, polyvinyl pyrrolidone, polyvinyl chloride, polycarbonate, polyimide, polyether sulfone, polybenzimidazole, polyethylene terephthalate, and polybutylene terephthalate.

[0018] A temperature-triggered reversible adhesive conductive film is prepared by adopting the preparation method.

[0019] A temperature-triggered reversibly adhesive conductive film is used as an electrode patch in motion monitoring, epidermal sensing, wearable electronics, and adhesives.

[0020] The advantages and beneficial effects of the present invention are:

[0021] The present invention utilizes the property of phase change polymers with adjustable modulus at different temperatures, uses it as a film substrate, and then mixes it with conductive materials and other auxiliary materials. The modulus change is controlled by temperature, and the film cannot adhere under low-temperature and high-modulus conditions, but can adhere under high-temperature and low-modulus conditions. This realizes a film that can adhere on demand and is conductive as a whole. It has broad application prospects in the fields of motion monitoring, epidermal sensing, and wearable electronics. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Figure 1 shows the process of adhering and removing the conductive film of the present invention from the skin;

[0023] Figure 2 This is a graph showing the modulus change of the temperature-triggered reversible adhesive conductive film of the present invention;

[0024] Figure 3 This is an operation flow chart of Example 3 of the conductive film of the present invention;

[0025] Figure 4 This is a 90° peel test diagram of the conductive film of the present invention as an adhesive at room temperature and human skin temperature;

[0026] Figure 5 This is an electrocardiogram signal image collected by the conductive film of the present invention as an electrode patch;

[0027] Figure 6 This is a graph of myoelectric signals collected using the conductive film of the present invention as an electrode patch. DETAILED DESCRIPTION

[0028] The present invention will be further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the scope of protection of the present invention cannot be limited thereto.

[0029] Example 1

[0030] A method for preparing a temperature-triggered reversibly adhesive conductive film, the innovation of which lies in the following steps:

[0031] Choline chloride and phenylacetic acid were mixed in a molar ratio of 1:2 to form a deep eutectic solvent, hexadecyl acrylate and tetradecyl acrylate were mixed in a mass ratio of 8:2 to form a side chain phase transition polymer, the deep eutectic solvent and the side chain phase transition polymer were mixed in a mass ratio of 6:4, and then mixed with CN6290 in a mass ratio of 95:5, 2.5wt% of a photoinitiator 2,2-dimethoxy-2-phenylacetophenone was added, and the mixture was heated and stirred at 80°C for 3 hours to obtain a conductive film precursor ink;

[0032] The conductive film precursor ink obtained above is coated on a polytetrafluoroethylene substrate;

[0033] The film was UV-cured at room temperature for 20 min and peeled off from the polytetrafluoroethylene substrate to obtain a temperature-triggered reversibly adhesive conductive film.

[0034] The temperature-triggered reversible adhesive conductive film of the present invention can be well adhered to the skin after reaching the phase transition temperature, and can be peeled off from the skin intact when it is lower than the phase transition temperature. Figure 1 As shown; the prepared temperature-triggered reversible adhesive conductive film can achieve modulus transformation at different temperatures, such as Figure 2 As shown; moreover, when the phase transition temperature is reached, the peel strength can reach an average of about 500N / m, which fully meets the application standards as an adhesive, such as Figure 4 As shown; Figure 5 and Figure 6 The electrophysiological signal detection results are performed by using a temperature-triggered reversibly adhesive conductive film as an electrode patch, which can achieve accurate detection of electrocardiographic, electromyographic and other signals.

[0035] Example 2

[0036] A method for preparing a temperature-triggered reversibly adhesive conductive film, the innovation of which lies in the following steps:

[0037] Choline chloride and phenylacetic acid were mixed in a molar ratio of 1:3 to form a low eutectic solvent, octadecyl acrylate and tetradecyl acrylate were mixed in a mass ratio of 7:3 to form a side chain phase transition polymer, the low eutectic solvent and the side chain phase transition polymer were mixed in a mass ratio of 5:5, and then mixed with trimethylolpropane triacrylate in a mass ratio of 8:2, 2.5 wt% of a photoinitiator 2,2-dimethoxy-2-phenylacetophenone was added, and the mixture was heated and stirred at 80°C for 3 hours to obtain a conductive film precursor ink;

[0038] Applying the conductive film precursor ink obtained above on a glass substrate;

[0039] The film was UV-cured at room temperature for 20 min and peeled off from the glass substrate to obtain a temperature-triggered reversibly adhesive conductive film.

[0040] Example 3

[0041] like Figure 3 As shown, a method for preparing a temperature-triggered reversible adhesive conductive film is innovative in that the method comprises the following steps:

[0042] A mixture of octadecyl acrylate and tetradecyl acrylate was mixed in a mass ratio of 6:4 to form a side chain phase transition polymer, a PEDOT:PSS dispersion was mixed with the side chain phase transition polymer in a mass ratio of 3:7, and then mixed with CN9021 in a mass ratio of 8:2. 3 wt% of the surfactant Span 20 and 2.5 wt% of the photoinitiator 2,2-dimethoxy-2-phenylacetophenone were added, and the mixture was heated and stirred at 80°C for 3 h to obtain a conductive film precursor ink;

[0043] The conductive film precursor ink obtained above is coated on a polyvinyl pyrrolidone substrate;

[0044] The film was UV-cured at room temperature for 20 min and peeled off from the polyvinyl pyrrolidone substrate to obtain a temperature-triggered reversibly adhesive conductive film.

[0045] Example 4

[0046] A method for preparing a temperature-triggered reversibly adhesive conductive film, the innovation of which lies in the following steps:

[0047] A mixture of hexadecyl methacrylate and dodecyl methacrylate was mixed in a mass ratio of 5:5 to form a side chain phase transition polymer, a MXene dispersion was mixed with the side chain phase transition polymer in a mass ratio of 3:7, and then mixed with hexanediol diacrylate in a mass ratio of 8:2, 3wt% of surfactant Tween 80 and 2.5wt% of photoinitiator 2,2-dimethoxy-2-phenylacetophenone were added, and the mixture was heated and stirred at 80°C for 3h to obtain a conductive film precursor ink;

[0048] The conductive film precursor ink obtained above is coated on a polyvinyl chloride substrate;

[0049] The film was UV-cured at room temperature for 20 min and peeled off from the polyvinyl chloride substrate to obtain a temperature-triggered reversibly adhesive conductive film.

[0050] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A method for preparing a temperature-triggered reversibly adhesive conductive film, characterized in that: The steps of the method are: S1. Mixing the side chain phase transition monomer, conductive material, auxiliary material and initiator in proportion to obtain a temperature-triggered reversible adhesion conductive film precursor ink; S2, evenly coating the precursor ink prepared in S1 on the substrate; S3. The precursor ink coated on the substrate in S2 is cured and peeled off from the substrate to obtain a temperature-triggered reversible adhesive conductive film.

2. The method for preparing a temperature-triggered reversible adhesive conductive film according to claim 1, wherein: The side chain phase transition monomer is one or more of octadecyl acrylate, hexadecyl acrylate, myristyl acrylate, dodecyl acrylate, octadecyl methacrylate, hexadecyl methacrylate, myristyl methacrylate, and dodecyl methacrylate.

3. The method for preparing a temperature-triggered reversibly adhesive conductive film according to claim 1, wherein: The conductive material is one or more of a deep eutectic solvent, an ionic liquid, a conductive polymer, a metal nanomaterial, a metal powder, MXene, graphene, a carbon nanotube, and carbon powder.

4. The method for preparing a temperature-triggered reversibly adhesive conductive film according to claim 1, wherein: The auxiliary material is a long-chain cross-linking agent or a surfactant; the long-chain cross-linking agent is one or more of Sartomer's CN6021, Sartomer's CN8888, Sartomer's CN9021, Sartomer's CN6290, trimethylolpropane triacrylate, polyurethane diacyl acid, polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and trimethylolpropane trimethacrylate; the surfactant is one or more of Span 80 / sorbitan monooleate, Tween 80 / polyoxyethylene sorbitan monooleate, Span 20 / sorbitan monolaurate, Tween 20 / polyoxyethylene sorbitan monolaurate, sodium lauryl sulfate, and dodecyldimethylammonium oxide.

5. The method for preparing a temperature-triggered reversible adhesive conductive film according to claim 4, wherein: The mass fraction of the side chain phase transition monomer in the conductive film precursor ink is higher than 30%, the mass fraction of the conductive material is higher than 10%, the mass fraction of the long chain crosslinking agent is not higher than 30%, and the mass fraction of the initiator is not higher than 10%.

6. The method for preparing a temperature-triggered reversibly adhesive conductive film according to claim 1, wherein: The initiator is a thermal initiator or a photoinitiator.

7. The method for preparing a temperature-triggered reversibly adhesive conductive film according to claim 1, wherein: The material of the substrate is selected from one or more of glass, polystyrene, polyvinyl alcohol, polytetrafluoroethylene, polylactic acid, polyethylene oxide, polyvinyl acetate, polyacrylic acid, polycaprolactone, polyacrylonitrile, polyvinyl pyrrolidone, polyvinyl chloride, polycarbonate, polyimide, polyether sulfone, polybenzimidazole, polyethylene terephthalate, and polybutylene terephthalate.

8. A temperature-triggered reversibly adhesive conductive film, characterized in that: The preparation method is as described in any one of claims 1 to 7.

9. Application of the temperature-triggered reversibly adhesive conductive film as claimed in claim 8 as an electrode patch in motion monitoring, epidermal sensing, wearable electronics and adhesives.

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