Method for preparing reversible adhesive flexible conductive film through aerosol jet printing

Abstract

The invention relates to a method for preparing a reversible adhesive flexible conductive film through aerosol jet printing. The method comprises the following steps: S1, preparing a phase transition polymer film; s2, preparing conductive ink; and S3, preparing the reversible adhesive flexible conductive film. According to the invention, the modulus change of the phase transition polymer is controlled by using temperature, and the phase transition polymer is used as a substrate of the conductive film, so that the conductive ink is completely transferred in an aerosol jet printing mode in a low-temperature and high-modulus state, and the adhesive and peelable conductive film is prepared; the method has a wide prospect in the application fields of electrophysiological signal monitoring, epidermal sensing, wearable electronics and the like.

Description

Technical Field

[0001] The invention belongs to the field of flexible electronic technology, and in particular relates to a method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing. Background Art

[0002] Flexible electronics have attracted much attention due to their various potential applications in human-computer interaction and electrophysiological signal monitoring. In order to improve the accuracy of the signal, it is necessary to reduce the signal-to-noise ratio, so flexible electronics with high adhesion have been widely studied.

[0003] In flexible electronics, flexible conductive films are a hot topic of research, and their good conductivity and adhesion are the key to signal acquisition and transmission. However, high adhesion interfaces can irritate the skin during the peeling process, causing secondary damage; at the same time, high adhesion interfaces can damage the device structure during the peeling process, affecting the device's service life.

[0004] Therefore, developing a conductive film with simple preparation methods, adhesion and peelability, and stable electrodes is crucial to achieving efficient integration and stable performance of flexible electronic devices. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing.

[0006] The present invention solves the technical problem by the following technical solutions:

[0007] A method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing, the method comprising the steps of:

[0008] S1, uniformly mixing a side chain phase transition monomer, a long chain crosslinking agent and an initiator to obtain a phase transition polymer precursor liquid, and curing the phase transition polymer precursor liquid to obtain a phase transition polymer film;

[0009] S2, uniformly mixing the conductive material and the high boiling point solvent in proportion to obtain a conductive ink;

[0010] S3, printing the conductive ink of S2 on the phase change polymer film of S1 by aerosol jet printing to obtain a reversibly adhesive flexible conductive film.

[0011] Moreover, the side chain phase transition monomer is one or more of octadecyl acrylate, hexadecyl acrylate, tetradecyl acrylate, octadecyl methacrylate, hexadecyl methacrylate, tetradecyl methacrylate, and dodecyl methacrylate.

[0012] Moreover, the mass fraction of the side chain phase transition monomer in the phase transition polymer precursor liquid is higher than 60%, and the mass fraction of the cross-linking agent is lower than 40%.

[0013] Moreover, the long-chain crosslinking agent is one or more of CN6021, CN8888, CN9021, trimethylolpropane triacrylate, polyurethane diacrylate, polyethylene glycol polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

[0014] Moreover, the initiator is a thermal initiator or a photoinitiator.

[0015] Moreover, the concentration of the conductive material in the S2 conductive ink is 1-50 mg / ml, and the mass fraction of the high boiling point solvent in the conductive ink is 1%-30%.

[0016] Moreover, the atomization mode of the aerosol jet printing is pneumatic atomization or ultrasonic atomization.

[0017] Moreover, the nozzle size of the aerosol jet printing is 200-800 μm, the temperature of the workbench is 20-100° C., the printing speed is 1-15 mm / s, the height of the printing nozzle from the printing bottom is 5-30 mm, and the number of cycle printing is 10-60 times.

[0018] The advantages and beneficial effects of the present invention are:

[0019] The present invention utilizes temperature to control the modulus change of phase-change polymers, uses it as the substrate of a conductive film, and enables the conductive ink to be completely transferred by aerosol jet printing under low-temperature and high-modulus conditions to form an adherent and peelable conductive film, which has broad prospects in the application fields of electrophysiological signal monitoring, epidermal sensing, wearable electronics, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a flow chart of the present invention;

[0021] Figure 2 DMA image of the reversibly adhesive flexible conductive film obtained by the present invention;

[0022] Figure 3 This is a 90° peeling test diagram of the flexible film of the present invention;

[0023] Figure 4 Figure 2 is a diagram showing the adhesion and removal of the flexible film of the present invention on the skin;

[0024] Figure 5 This is an electron microscope morphology image of the conductive ink lines printed by aerosol jetting of the present invention;

[0025] Figure 6 The electrocardiogram tested by the aerosol jet printing flexible conductive film of the present invention;

[0026] Figure 7 This is the electromyogram tested by the aerosol jet printing flexible conductive film of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

[0028] Example 1

[0029] A method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing, such as Figure 1 As shown, the innovation lies in that the steps of the method are:

[0030] 1. Hexadecyl acrylate and tetradecyl acrylate were mixed in a mass ratio of 98:2, the mixture of hexadecyl acrylate and tetradecyl acrylate and polypropylene glycol diacrylate were mixed in a mass ratio of 95:5, 1 wt% of photoinitiator 2,2-dimethoxy-2-phenylacetophenone was added, heated and stirred at 80°C for 3h, and then ultrasonicated for 30 minutes to obtain a phase change polymer precursor liquid;

[0031] 2. Drop the phase change polymer precursor obtained above on the substrate, UV cure it at room temperature for 20 minutes, and peel it off from the polystyrene substrate to obtain a flexible, transparent film that can be adhered as needed;

[0032] 3. Mix MXene with a concentration of 10 mg / mL, PEDOT:PSS (poly(3,4-ethylenedioxythiophene)-polystyrene sulfonate) with a concentration of 5 mg / ml, and 1% EG (ethylene glycol) evenly, then adjust the aerosol jet printing, select the ultrasonic atomization method, select a 200 μm nozzle, a printing speed of 5 mm / s, a carrier gas of 30 sccm, a sheath gas of 50 sccm, and print 20 times to obtain an easily peelable flexible conductive film.

[0033] The flexible conductive film prepared by the present invention can realize the transformation of modulus at different temperatures, such as Figure 2 As shown in FIG. 1 , when the phase transition temperature is reached, the peel strength can reach an average of about 31 N / m. Figure 3 The film can fit the skin well and can be peeled off from the skin intact when the temperature drops below a certain level. Figure 4 As shown; Figure 5This is the pattern printed this time and the morphology observed under an electron microscope. Due to multiple printings, it can be seen that the ink is closely connected together to form a conductive path. Figure 6 and Figure 7 The electrophysiological signal detection results of the flexible conductive film achieved by aerosol jet printing can realize the accurate detection of ECG, EMG and other signals.

[0034] Example 2

[0035] A method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing, the innovation of which lies in the following steps:

[0036] 1. Octadecyl acrylate and tetradecyl acrylate were mixed in a mass ratio of 4:3, the mixture of octadecyl acrylate and tetradecyl acrylate and polyurethane diacyl acid were mixed in a mass ratio of 8:2, 1 wt% of photoinitiator 2,2-dimethoxy-2-phenylacetophenone was added, heated and stirred at 80°C for 3h, and then ultrasonicated for 30 minutes to obtain a phase change polymer precursor liquid;

[0037] 2. Drop the phase-change polymer precursor obtained above on the substrate, UV-curing it at room temperature for 20 minutes, and peeling it off from the glass substrate to obtain a flexible, transparent film that can be adhered as needed.

[0038] 3. Mix MXene with a concentration of 15 mg / mL, PEDOT:PSS with a concentration of 10 mg / ml, and 5% EG evenly, then adjust the aerosol jet printing, select the pneumatic atomization method, select a 300 μm nozzle, a printing speed of 8 mm / s, a carrier gas of 60 sccm, a sheath gas of 120 sccm, and print 30 times to obtain an easily peelable flexible conductive film.

[0039] Example 3

[0040] A method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing, the innovation of which lies in the following steps:

[0041] 1. Mix octadecyl acrylate and dodecyl methacrylate in a mass ratio of 7:3, mix the mixture of octadecyl acrylate and dodecyl methacrylate and CN8888 in a mass ratio of 9:1, heat and stir at 80°C for 3h, wait for the mixture to cool, add 1wt% thermal initiator potassium persulfate, stir quickly and evenly, and then ultrasonicate for 30 minutes to obtain a phase change polymer precursor liquid;

[0042] 2. Drop the phase change polymer precursor obtained above on the substrate, UV-curing it at room temperature for 20 minutes, and peeling it off from the polyvinyl pyrrolidone substrate to obtain a flexible, transparent film that can be adhered as needed.

[0043] 3. Mix MXene with a concentration of 20 mg / mL, PEDOT:PSS with a concentration of 10 mg / ml, and 10% EG evenly, then adjust the aerosol jet printing, select the pneumatic atomization method, select a 300 μm nozzle, a printing speed of 10 mm / s, a carrier gas of 60 sccm, a sheath gas of 200 sccm, and print 30 times to obtain an easily peelable flexible conductive film.

[0044] Example 4

[0045] A method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing, the innovation of which lies in the following steps:

[0046] 1. Hexadecyl methacrylate and dodecyl methacrylate were mixed in a mass ratio of 98:2, the mixture of hexadecyl methacrylate and dodecyl methacrylate and trimethyl propane trimethacrylate were mixed in a mass ratio of 9:1, 1 wt% of photoinitiator benzophenone was added, heated and stirred at 80°C for 3h, and then ultrasonicated for 30 minutes to obtain a phase change polymer precursor liquid;

[0047] 2. Drop the phase change polymer precursor obtained above on the substrate, UV-cure it at room temperature for 20 minutes, and peel it off from the polyvinyl chloride substrate to obtain a flexible, transparent film that can be adhered as needed.

[0048] 3. Mix MXene with a concentration of 30 mg / mL, PEDOT:PSS with a concentration of 15 mg / ml, and 10% EG evenly, then adjust the aerosol jet printing, select the ultrasonic atomization method, select a 500 μm nozzle, a printing speed of 10 mm / s, a carrier gas of 80 sccm, a sheath gas of 160 sccm, and print 20 times to obtain an easily peelable flexible conductive film.

[0049] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate 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 reversibly adhesive flexible conductive film by aerosol jet printing, characterized in that: The steps of the method are: S1, uniformly mixing a side chain phase transition monomer, a long chain crosslinking agent and an initiator to obtain a phase transition polymer precursor liquid, and curing the phase transition polymer precursor liquid to obtain a phase transition polymer film; S2, uniformly mixing the conductive material and the high boiling point solvent in proportion to obtain a conductive ink; S3, printing the conductive ink of S2 on the phase change polymer film of S1 by aerosol jet printing to obtain a reversibly adhesive flexible conductive film.

2. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The side chain phase transition monomer is one or more of octadecyl acrylate, hexadecyl acrylate, tetradecyl acrylate, octadecyl methacrylate, hexadecyl methacrylate, tetradecyl methacrylate and dodecyl methacrylate.

3. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The mass fraction of the side chain phase transition monomer in the phase transition polymer precursor liquid is higher than 60%, and the mass fraction of the cross-linking agent is lower than 40%.

4. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The long-chain crosslinking agent is one or more of CN6021, CN8888, CN9021, trimethylolpropane triacrylate, polyurethane diacrylate, polyethylene glycol polyethylene glycol diacrylate, polypropylene glycol diacrylate, hexanediol diacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, and trimethylolpropane trimethacrylate.

5. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The initiator is a thermal initiator or a photoinitiator.

6. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The concentration of the conductive material in the S2 conductive ink is 1-50 mg / ml, and the mass fraction of the high boiling point solvent in the conductive ink is 1%-30%.

7. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The atomization method of the aerosol jet printing is pneumatic atomization or ultrasonic atomization.

8. The method for preparing a reversibly adhesive flexible conductive film by aerosol jet printing according to claim 1, characterized in that: The nozzle size of the aerosol jet printing is 200-800 μm, the temperature of the workbench is 20-100° C., the printing speed is 1-15 mm / s, the height of the printing nozzle from the printing bottom is 5-30 mm, and the number of cycle printing is 10-60 times.

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