Hydrophilic modified PDMS composite material and flexible circuit preparation method thereof
By using hydrophilic modification of PDMS composite materials and the dip-coating self-assembly method to prepare flexible circuits, the problems of low production efficiency and poor adhesion of conductive circuits on the PDMS surface are solved, realizing the preparation of flexible circuits with high efficiency and low cost, which is suitable for flexible wearable electronic devices.
Patent Information
- Application Number
- CN202510987835.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-11-07
AI Technical Summary
Existing technologies struggle to efficiently fabricate conductive circuits on PDMS surfaces, resulting in low production efficiency, high costs, and poor film adhesion.
A flexible circuit was fabricated by using hydrophilic modified PDMS composite material, which was prepared by mixing PDMS liquid, crosslinking agent and siloxane liquid, and then curing it by scraping and using a lifting machine to make conductive ink self-assemble into a conductive film.
The improved hydrophilicity of PDMS solved the problem of conductive material adhesion, enabling low-cost, large-scale fabrication of flexible circuits with commercial potential.
Smart Images
Figure CN120904515A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of composite materials, in particular to a hydrophilic modified PDMS composite material and a flexible circuit preparation method thereof. BACKGROUND
[0002] Since the 21st century, with the development of economy and digitalization and informatization, the demand for precision medicine has been increasing, which has given rise to the demand for the deep integration of traditional medical technology and digital space. Traditional human body sensors have defects such as volume limitation, poor biocompatibility, and poor skin adhesion due to their hard and rigid characteristics, and it is difficult to maintain long-term stable monitoring in a dynamic human body environment. This demand has promoted the development of flexible wearable electronic devices.
[0003] A flexible wearable electronic device is a microsystem formed by heterogeneously integrating a flexible polymer substrate, a low-dimensional conductive material, a flexible circuit, and a wireless transmission module. Common flexible polymer substrates include polydimethylsiloxane (PDMS), polyimide (PI), polyethylene terephthalate (PET), and other materials. However, PI, PET, and other materials have problems such as poor biocompatibility and insufficient flexibility. PDMS is widely used due to its similar Young's modulus to skin and excellent biocompatibility. However, due to the presence of a large number of methyl groups in PDMS, it has poor polarity, low surface energy, and other problems such as hydrophobicity and weak interaction with low-dimensional conductive materials. These problems make it difficult to prepare conductive circuits on the surface of PDMS. Some methods have been developed to prepare conductive films on the surface of PDMS, including thermal evaporation, magnetron sputtering, and other methods. However, these methods have problems such as low production efficiency, high cost, and poor film adhesion, which restrict the application of PDMS in flexible wearable electronic devices. SUMMARY
[0004] The present application aims to solve the problems of low production efficiency, high cost, and poor film adhesion in preparing conductive circuits on the surface of PDMS. A hydrophilic modified PDMS composite material is proposed, which includes PDMS liquid, crosslinking agent, and siloxane liquid. The three are thoroughly stirred and evenly spread on a glass plate for curing.
[0005] The present application also proposes a method for preparing a flexible circuit using the above-mentioned hydrophilic modified PDMS composite material, which specifically includes the following steps: S1: Mix the PDMS liquid and the crosslinking agent in proportion, thoroughly stir and evenly spread on a glass plate for curing. S2: Add the siloxane liquid to the liquid obtained in step S1, thoroughly stir and evenly spread on a glass plate for curing. S3: Pour the liquid obtained in step S2 on a glass plate, scrape flat with a film scraper, and solidify at 100 DEG C for 40 min to obtain a hydrophilic modified PDMS composite material film; S4: Place the beaker containing the conductive ink on a pulling machine, repeatedly immerse and pull the hydrophilic modified PDMS composite material film with the pulling machine, so that the conductive ink self-assembles on the surface of the film to form a conductive film, and obtain a flexible circuit based on the hydrophilic modified PDMS composite material.
[0006] The further arrangement of the application is that the mass ratio of the PDMS liquid to the crosslinking agent in step S1 is 10:1.
[0007] The further arrangement of the application is that the siloxane liquid in step S2 is poly [dimethylsiloxane-co-(3-aminopropyl)methylsiloxane] or poly (dimethylsiloxane), bis (hydroxyalkyl) -terminated, or a mixture of the two.
[0008] The further arrangement of the application is that the mass of the siloxane liquid in step S2 is 1-9% of the PDMS liquid.
[0009] The further arrangement of the application is that after scraping flat with the film scraper in step S3, the film is left to stand in the natural environment for 10 min, so that the bubbles are separated automatically.
[0010] The further arrangement of the application is that the immersion and pulling speed in step S4 is 40-80 mm / min.
[0011] The further arrangement of the application is that the conductive ink in step S4 is one or more of MXene dispersion, graphene dispersion, reduced graphene oxide dispersion, carbon nanotube dispersion and conductive silver paste, and the concentration is 20 mg / ml.
[0012] The application has the beneficial effect that the hydrophilic modified PDMS composite material flexible circuit preparation method disclosed in the application greatly improves the hydrophilic ability of PDMS, solves the problems of difficulty in attaching conductive materials to the surface of silane-based polymers and difficulty in developing flexible circuits, can be prepared on a large scale at low cost, and has great commercialization potential. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 The structural formulae of the PDMS, poly [dimethylsiloxane-co-(3-aminopropyl)methylsiloxane] and poly (dimethylsiloxane), bis (hydroxyalkyl) -terminated used in the application are shown.
[0014] Figure 2Contact angles of water and water-ethanol binary solutions on PDMS / poly[di- methylsiloxane-co-(3-aminopropyl)methylsiloxane] composites prepared in the present invention with different mass fractions of poly[di-methylsiloxane-co-(3- aminopropyl)methylsiloxane] 0-9 wt.%.
[0015] Figure 3 Contact angles of water and water-ethanol binary solutions on PDMS / poly[di- methylsiloxane-co-(3-aminopropyl)methylsiloxane] / poly(dimethylsiloxane), bis(hydroxyalkyl) terminated composites prepared in the present invention with different mass fractions of m(poly[di-methylsiloxane-co-(3-aminopropyl)methylsiloxane]):m(poly(dimethylsiloxane), bis(hydroxyalkyl) terminated) = 1:1, 0-9 wt.%.
[0016] Figure 4 Scanning electron microscope images of the surface of a flexible circuit prepared by the pull-up self-assembly method using the hydrophilic modified PDMS composite prepared in the present invention.
[0017] Figure 5 Scanning electron microscope images of the edge of a flexible circuit prepared by the pull-up self-assembly method using the hydrophilic modified PDMS composite prepared in the present invention.
[0018] Figure 6 Scanning electron microscope images of the cross section of a flexible circuit prepared by the pull-up self-assembly method using the hydrophilic modified PDMS composite prepared in the present invention.
[0019] Figure 7 Scanning electron microscope images of the surface of a flexible circuit prepared by the drop coating method using the hydrophilic modified PDMS composite prepared in the present invention.
[0020] Figure 8 Scanning electron microscope images of the edge of a flexible circuit prepared by the drop coating method using the hydrophilic modified PDMS composite prepared in the present invention.
[0021] Figure 9 Scanning electron microscope images of the cross section of a flexible circuit prepared by the drop coating method using the hydrophilic modified PDMS composite prepared in the present invention. DETAILED DESCRIPTION
[0022] Those skilled in the art can improve the process parameters according to the content herein. In particular, it should be pointed out that all similar substitutions and changes are obvious to those skilled in the art, and they are considered to be included in the present application. The methods and applications of the present application have been described by preferred embodiments, and relevant personnel can modify or appropriately change and combine the methods and applications described herein without departing from the content, spirit and scope of the present application to realize and apply the present application technology.
[0023] Embodiment 1
[0024] The present application provides a hydrophilic modified PDMS composite material, which comprises a PDMS liquid, a crosslinking agent and a siloxane liquid, which are fully stirred and uniformly scraped on a glass plate and solidified.
[0025] Embodiment 2
[0026] The present embodiment provides a method for preparing a flexible circuit using the hydrophilic modified PDMS composite material disclosed in embodiment 1, which specifically comprises the following steps:
[0027] S1: Mix the PDMS liquid and the crosslinking agent in proportion, fully stir and uniformly, and degas in an environment of 200 Pa vacuum degree for 30 min.
[0028] S2: Add the siloxane liquid to the liquid obtained in step S1, fully stir and uniformly.
[0029] S3: Pour the liquid obtained in step S2 on a glass plate, scrape it flat with a film scraper, and solidify at 100℃ for 40 min to obtain a hydrophilic modified PDMS composite material film.
[0030] S4: Place a beaker containing conductive ink on a puller, repeatedly immerse and pull the hydrophilic modified PDMS composite material film with the puller, so that the conductive ink self-assembles on the surface of the film to form a conductive film, and obtain a flexible circuit based on the hydrophilic modified PDMS composite material.
[0031] In step S1, the mass ratio of the PDMS liquid to the crosslinking agent is 10:1.
[0032] In step S2, the siloxane liquid is poly[di-methyl siloxane-co-(3-aminopropyl) methyl siloxane] or poly(dimethylsiloxane), bis(hydroxyalkyl) terminated, or a mixture thereof.
[0033] In step S2, the mass of the siloxane liquid is 1-9% of the PDMS liquid.
[0034] In step S3, after scraping with a film scraper, stand for 10 min in a natural environment to allow bubbles to separate by themselves, without the need for vacuum degassing.
[0035] wherein the intrusion, pulling speed in step S4 is 40-80 mm / min.
[0036] wherein the conductive ink in step S4 is one or several of MXene dispersion, graphene dispersion, reduced graphene oxide dispersion, carbon nanotube dispersion and conductive silver paste, and the concentration is 20 mg / ml.
[0037] Example 3
[0038] In this embodiment, the hydrophilic modified PDMS composite flexible circuit is prepared by the method disclosed in Example 2, specifically comprising the following steps:
[0039] S1: Mix the PDMS liquid and the crosslinking agent in a ratio of 10:1, fully stir uniformly, and degas in an environment of 200 Pa vacuum degree for 30 min.
[0040] S2: Add poly[di-methylsiloxane-co-(3-aminopropyl)methylsiloxane] to the liquid obtained in step S1, and the mass is 5% of the PDMS liquid, fully stir uniformly.
[0041] S3: Pour the liquid obtained in step S2 on a glass sheet, scrape flat with a film scraper, and stand for 10 min to allow the bubbles to self-detach, without the need for vacuum degassing. Then cure at an environment of 100°C for 40 min to obtain a hydrophilic modified PDMS composite film.
[0042] S4: Place a beaker containing MXene dispersion with a concentration of 20 mg / ml on the pulling machine, and repeatedly immerse and pull the hydrophilic modified PDMS composite glass with the pulling machine at a speed of 80 mm / min, so that the conductive ink self-assembles on the surface of the film to form a conductive film, to obtain a hydrophilic modified PDMS composite-based flexible circuit.
[0043] Example 4
[0044] In this embodiment, the hydrophilic modified PDMS composite flexible circuit is prepared by the method disclosed in Example 2, specifically comprising the following steps:
[0045] S1: Mix the PDMS liquid and the crosslinking agent in a ratio of 10:1, fully stir uniformly, and degas in an environment of 200 Pa vacuum degree for 30 min.
[0046] S2: Add a mixture of poly[di-methylsiloxane-co-(3-aminopropyl)methylsiloxane] and poly(dimethylsiloxane) with a mass ratio of 1:1 to the liquid obtained in step S1, and the mass is 5% of the PDMS liquid, fully stir uniformly.
[0047] S3: Pour the liquid obtained in step S2 on a glass sheet, level it with a film scraper, and let it stand for 10 min to allow the bubbles to detach by themselves, without the need for vacuum degassing. Then cure it at 100°C for 40 min to obtain a hydrophilic modified PDMS composite film.
[0048] S4: Place a beaker containing a MXene dispersion liquid with a concentration of 20 mg / ml on a pulling machine, and repeatedly immerse and pull the hydrophilic modified PDMS composite glass with the pulling machine at a speed of 80 mm / min, so that the conductive ink self-assembles on the surface of the film to form a conductive film, thereby obtaining a flexible circuit based on the hydrophilic modified PDMS composite material.
[0049] Reference Figure 4 , 5 , 6, shows the surface, edge and cross-section of the flexible circuit prepared in this embodiment, and it can be seen that the surface is uneven, and the edge and cross-section are not uniform in thickness.
[0050] Example 5
[0051] In this embodiment, the hydrophilic modified PDMS composite flexible circuit is prepared by the method disclosed in Example 2, which specifically comprises the following steps:
[0052] S1: Mix the PDMS liquid with the crosslinking agent at a ratio of 10:1, fully stir to uniform, and degas under the environment of 200 Pa vacuum degree for 30 min.
[0053] S2: Add poly[di-methylsiloxane-co-(3-aminopropyl)methylsiloxane] and poly(dimethylsiloxane) to the liquid obtained in step S1, and the mixture of bis(hydroxyalkyl) end-capped mass ratio is 1:1, and its mass is 5% of the PDMS liquid, fully stir to uniform.
[0054] S3: Pour the liquid obtained in step S2 on a glass sheet, level it with a film scraper, and let it stand for 10 min to allow the bubbles to detach by themselves, without the need for vacuum degassing. Then cure it at 100°C for 40 min to obtain a hydrophilic modified PDMS composite film.
[0055] S4: Directly drop the MXene dispersion liquid with a concentration of 20 mg / ml on the hydrophilic modified PDMS composite film, and dry it in a vacuum heated environment, so that the MXene dispersion liquid forms a conductive film on the surface of the film, thereby obtaining a flexible circuit based on the hydrophilic modified PDMS composite material.
[0056] Reference Figure 7 , 8 , 9, shows the surface, edge and cross-section of the flexible circuit prepared in this embodiment, and it can be seen that the surface is uneven, and the edge and cross-section are not uniform in thickness.
[0057] In summary, the present application prepares a hydrophilic modified PDMS composite material by mixing PDMS with poly[dimethylsiloxane-co-(3-aminopropyl)methylsiloxane] and poly(dimethylsiloxane), bis(hydroxyalkyl) terminated, and further prepares a flexible circuit by a pull-and-pull self-assembly method. This preparation method is simple, convenient, low in cost, high in efficiency, and can be mass-produced, and has great commercial potential. The hydrophilic modified PDMS composite material prepared according to this preparation method uses various conductive inks to prepare a flexible circuit, and the prepared flexible circuit can be used to build a flexible wearable electronic device system.
[0058] The above only describes the preferred embodiments of the present application, and it should be noted that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be within the scope of protection of the present application.
Claims
1. A hydrophilically modified PDMS composite, characterized in that, The PDMS liquid, the crosslinking agent and the siloxane liquid are fully stirred and mixed, and are scraped flat on a glass plate and cured.
2. A method for manufacturing a flexible circuit using the hydrophilic-modified PDMS composite according to claim 1, characterized by, Specifically comprising the following steps: S1: the PDMS liquid and the crosslinking agent are mixed in proportion, fully stirred and mixed, and are degassed under the environment of 200 Pa vacuum degree for 30 min; S2: the siloxane liquid is added to the liquid obtained in step S1, and is fully stirred and mixed; S3: the liquid obtained in step S2 is poured on a glass plate, is scraped flat by a film scraper, is cured under the environment of 100℃ for 40 min, and a hydrophilic modified PDMS composite material thin film is obtained; S4: a beaker containing conductive ink is placed on a pulling machine, the hydrophilic modified PDMS composite material thin film is repeatedly immersed and pulled by the pulling machine, the conductive ink is self-assembled on the surface of the thin film to form a conductive film, and a flexible circuit based on the hydrophilic modified PDMS composite material is obtained.
3. The method for preparing flexible circuits using hydrophilically modified PDMS composite materials according to claim 2, characterized in that, The mass ratio of the PDMS liquid to the crosslinking agent in step S1 is 10:
1.
4. The method of claim 2, wherein the hydrophilic modified PDMS composite is used to prepare a flexible circuit. The siloxane liquid in step S2 is poly[di-methylsiloxane-co-(3-aminopropyl)methylsiloxane] or poly(dimethylsiloxane), bis(hydroxyalkyl)-terminated, or a mixture of the two.
5. The method for preparing flexible circuits using hydrophilic modified PDMS composite materials according to claim 2 or 4, characterized in that, The mass of the siloxane liquid in step S2 is 1-9% of the mass of the PDMS liquid.
6. The method of claim 2, wherein the hydrophilic modified PDMS composite is used to prepare a flexible circuit. After being scraped flat by the film scraper in step S3, the liquid is left to stand in the natural environment for 10 min, so that the bubbles are separated automatically.
7. The method of claim 2, wherein the hydrophilic modified PDMS composite is used to prepare a flexible circuit. The immersion and pulling speed in step S4 is 40-80 mm / min.
8. The method of claim 2, wherein the hydrophilic modified PDMS composite is used to prepare a flexible circuit. The conductive ink in step S4 is one or more of MXene dispersion, graphene dispersion, reduced graphene oxide dispersion, carbon nanotube dispersion and conductive silver paste, and the concentration is 20 mg / ml.