Low-stripping-force release film and preparation method thereof

Abstract

The invention discloses a release film with low stripping force. The release film takes polyethylene glycol terephthalate (PET) as a base material; a molybdenum disulfide (MoS2) layer made of a two-dimensional material is deposited on the surface of the PET base material through a chemical vapor deposition method; the surface of the molybdenum disulfide (MoS2) layer is coated with a self-repairing coating, and the self-repairing coating is formed by curing the following components: isopropyl alcohol; a thiol self-assembled molecule; quantum effect particles; polyethyleneimine (PEI) and a self-healing polymer. According to the invention, molybdenum disulfide (MoS2), quantum effect particles and self-assembled mercaptan molecules are combined in the design of the release film, and different characteristics of various materials are utilized to achieve a synergistic effect to realize low stripping force, self-repairing property and long-term durability. The multi-material composite structure not only can reduce the stripping force, but also has wider application potential and applicability.

Description

Technical Field

[0001] The present invention relates to the field of release films, and in particular to a low peeling force release film and a preparation method thereof. Background Art

[0002] Release films are widely used in adhesive materials, adhesive tapes, and optoelectronic device production. Their primary function is to prevent adhesives or other materials from adhering to the substrate surface during processing, thereby enabling smooth release. However, traditional release films often suffer from excessive peel force, poor abrasion resistance, or surface damage over time, leading to a gradual decline in functionality and failing to meet the demands of long-term, repeated use. Therefore, developing a release film with low peel force, self-healing capabilities, and high durability has become a key issue in this field.

[0003] In the prior art, release films are mainly used to reduce the peeling force by surface treatment or coating with materials with low friction coefficients. Two-dimensional materials such as graphene have gradually been introduced into the design of release films due to their unique mechanical and lubricating properties. However, the preparation cost of graphene is relatively high, and its compatibility with other functional materials in specific application scenarios has certain limitations. In addition, although the prior art has made certain progress in reducing the peeling force and enhancing the functionality of release films, there are still many challenges in how to make low peeling force, durability and other properties compatible in the same release film. Therefore, there is an urgent need to develop a low peeling force release film with excellent comprehensive performance to meet higher usage requirements. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a low peeling force release film and a preparation method thereof, so as to reduce or avoid the above-mentioned problems.

[0005] In order to solve the above technical problems, the present invention proposes a low peeling force release film, which uses polyethylene terephthalate (PET) as a substrate; a layer of two-dimensional material molybdenum disulfide (MoS2) is deposited on the surface of the PET substrate by chemical vapor deposition; a self-healing coating is coated on the surface of the molybdenum disulfide (MoS2) layer, and the self-healing coating is solidified by the following components: isopropyl alcohol; thiol self-assembly molecules; quantum effect particles; polyethyleneimine (PEI) and self-healing polymer.

[0006] Preferably, the thickness of the molybdenum disulfide layer is 5-15 nanometers.

[0007] Preferably, the thickness of the self-repairing coating is 10-100 nanometers.

[0008] Preferably, the thickness of the PET substrate is 25 μm to 80 μm.

[0009] Preferably, the weight percentages of the components constituting the self-healing coating are: 85wt%-90wt% of isopropyl alcohol, 0.5wt%-1.0wt% of 1-octanethiol, 2.0wt%-5.0wt% of zinc sulfide-coated cadmium selenide nanoparticles, 0.1wt%-0.5wt% of polyethyleneimine (PEI), and 5.0wt%-8.0wt% of polydimethylsiloxane (PDMS).

[0010] Preferably, the zinc sulfide-coated cadmium selenide nanoparticles are prepared from the following raw materials in parts by weight: 0.04-0.07 parts by weight of cadmium oxide; 0.03-0.06 parts by weight of selenium powder; 18-27 parts by weight of octadecene; 1-4 parts by weight of oleylamine; 1.5-3 parts by weight of oleic acid; 50-100 parts by weight of n-octane; 0.08-0.12 parts by weight of zinc acetate; 0.015-0.03 parts by weight of H2S gas; and 50-100 parts by weight of isopropyl alcohol.

[0011] The present invention also proposes a method for preparing the above-mentioned low peel force release film, comprising the following steps: using polyethylene terephthalate (PET) as a substrate, first cleaning the surface of the PET substrate; depositing a layer of molybdenum disulfide film on the PET substrate by CVD at 500°C-600°C, and cooling to room temperature; preparing a self-repairing coating solution; coating the prepared self-repairing coating solution on the surface of the molybdenum disulfide layer; after coating, placing the film in a drying oven and drying it at a temperature of 60°C to 80°C for 30-60 minutes; raising the temperature to 120°C-150°C to further cure the coating for 60-90 minutes.

[0012] Preferably, the self-healing coating solution is prepared by the following steps: first adding 85wt%-90wt% of isopropanol to a clean container; adding 0.5wt%-1.0wt% of 1-octanethiol to the container and stirring until completely dissolved; continuing to add 2.0wt%-5.0wt% of zinc sulfide-coated cadmium selenide to the container and stirring for 30-60 minutes; continuing to add 0.1wt%-0.5wt% of polyethyleneimine to the container and stirring for 30-60 minutes; continuing to add 5.0wt%-8.0wt% of PDMS to the container and continuing to stir for 30-60 minutes.

[0013] Preferably, the zinc sulfide-coated cadmium selenide nanoparticles are prepared by the following steps: adding 0.04-0.07 parts by weight of CdO, 1.5-3 parts by weight of oleic acid and 8-12 parts by weight of octadecene (ODE) to a three-necked flask, heating to 150°C under a nitrogen environment, and reacting until CdO is completely dissolved to form a Cd oleate solution; mixing 0.03-0.06 parts by weight of selenium powder with 1-4 parts by weight of oleylamine (OLA), and heating to 120°C in another flask to form a Se precursor solution; injecting the selenium precursor solution into the Cd oleate solution, and immediately raising the temperature to 300°C, maintaining the reaction for 1 hour, cooling to room temperature, and using 50-100 parts by weight of n-octane solvent to clean and precipitate the CdSe core; The cleaned CdSe cores prepared above were redispersed in 10-15 parts by weight of octadecene, heated to 80°C, and maintained in a nitrogen environment; 0.08-0.12 parts by weight of zinc acetate (Zn(OAc)2) was added at 80°C and stirred for 30-60 minutes; 0.015-0.03 parts by weight of H2S gas was introduced; the temperature was maintained at 100°C and the reaction was continued for 2 hours, after which the temperature was lowered to room temperature, and the product was washed and separated with 20-50 parts by weight of isopropanol to obtain ZnS@CdSe nanoparticles; the obtained ZnS@CdSe nanoparticles were centrifuged and repeatedly washed with 30-50 parts by weight of isopropanol; the washed ZnS@CdSe nanoparticles were vacuum dried and stored for later use.

[0014] Preferably, the temperature for vacuum drying of the ZnS@CdSe nanoparticles is 40° C.-60° C.; the drying time is 4-8 hours; and the pressure range is 0.1 mbar to 0.5 mbar.

[0015] This invention combines molybdenum disulfide (MoS2), quantum effect particles, and self-assembling thiol molecules in the design of the release film, leveraging the different properties of each material to synergistically achieve low peel force, self-healing, and long-term durability. This multi-material composite structure not only reduces peel force but also has a wider application potential and applicability. DETAILED DESCRIPTION

[0016] In order to have a clearer understanding of the technical features, objectives and effects of the present invention, the specific embodiments of the present invention are now described in detail, wherein the same components are marked with the same reference numerals.

[0017] The present invention proposes a low-peeling force release film, which uses polyethylene terephthalate (PET) as a substrate; a layer of two-dimensional material molybdenum disulfide (MoS2) is deposited on the surface of the PET substrate by chemical vapor deposition; a self-healing coating is coated on the surface of the molybdenum disulfide (MoS2) layer, and the self-healing coating is solidified by the following components: isopropyl alcohol; thiol self-assembly molecules; quantum effect particles; polyethyleneimine; and a self-healing polymer.

[0018] Among them, isopropyl alcohol (IPA) is a solvent; 1-octanethiol can be selected as the thiol self-assembly molecule; the quantum effect particles are zinc sulfide-coated cadmium selenide nanoparticles; polyethyleneimine (PEI) is used as a dispersant for the quantum effect particles; and the self-healing polymer can be selected from polydimethylsiloxane (PDMS).

[0019] Thiol self-assembling molecules (SAMs) are a class of organic molecules that can spontaneously assemble on specific surfaces through chemical bonding. Their self-assembly process relies primarily on the strong interaction between sulfur atoms and metal surfaces. The sulfur atoms at the end of the thiol molecule (R-SH) have a high affinity for metal surfaces, bonding to the metal atoms through covalent bonds or other strong interactions to form a stable chemically adsorbed layer. This is a key step in self-assembly, ensuring the molecules' strong attachment to the surface. Due to intermolecular van der Waals forces, the organic groups (such as alkyl chains) in the thiol molecules adsorbed on the metal surface tend to form a highly ordered monolayer with a specific orientation. As the adsorption process proceeds, the molecules align to minimize free energy, resulting in a denser and more ordered monolayer. The structural stability of the self-assembled molecular layer stems from two factors: the chemical bond formed between the sulfur atoms and the metal surface and the van der Waals and hydrophobic interactions between the molecular chains. The monolayer is highly stable and remains unchanged in water, air, and certain organic solvents. Thiol self-assembly molecules can reduce surface friction, lower peel force, and reduce the adhesion between adhesives and films. The strong bond between thiol self-assembly molecules and metal surfaces makes them very stable in chemical environments and less susceptible to oxidation or chemical attack, thereby improving the durability of coatings and release films.

[0020] Quantum effect particles, also known as quantum dots (QDs), are nanoscale semiconductor materials with unique optical and electronic properties. In this invention, these particles, through synergistic interaction with thiol self-assembling molecules and self-healing polymers, not only reduce the surface energy of the release film, thereby reducing peel force, but also impart unique optical and electronic properties to the film, enhancing its uniformity, durability, and self-healing capabilities, making it suitable for high-frequency use and complex environments.

[0021] The quantum effect particles in the present invention are nanoparticles of zinc sulfide-coated cadmium selenide, and the ZnS@CdSe quantum dots adopt a core-shell structure, in which CdSe provides quantum effects as the core and ZnS provides protection as the shell, which significantly enhances the chemical stability and mechanical strength of the quantum dots. This core-shell structure can prevent the CdSe core from being subjected to external chemical reactions or mechanical damage, ensuring that the quantum effect particles maintain their optical properties and surface properties after repeated use or in harsh environments. If quantum effect particles of a single material (such as CdSe or ZnO) are used, their stability is poor and they are more susceptible to environmental influences, resulting in performance degradation, especially in self-healing coatings where low peeling force and high durability cannot be maintained for a long time.

[0022] ZnS@CdSe quantum effect particles have tunable optical properties and can adjust the wavelength of emitted light by changing the core-shell size. This flexibility provides a choice of optical properties for release films, making them suitable for scenarios that require transparency or optical property control (such as optoelectronic devices or high-transmittance films). If other materials, such as ZnO or TiO2, are used, although these quantum dots have similar optical properties in some aspects, their tunability and luminous efficiency are generally lower, and they cannot provide such precise optical control, which may limit the application of release films in specific optical environments.

[0023] The surface of ZnS@CdSe quantum dots has been optimized and combined with thiol self-assembly molecules to significantly reduce the surface energy of the film, reduce adhesion, and thus effectively reduce peel force. Its core-shell structure gives it excellent lubrication properties in a variety of chemical environments, enhancing the ability to control the friction coefficient of the release film. If other quantum effect particles are replaced, such as simple CdSe or PbS quantum dots, although they may also provide certain quantum effects, their surface energy control effect is poor, which easily increases peel force, and their lubrication properties are not as good as ZnS@CdSe quantum dots.

[0024] ZnS@CdSe nanoparticles combined with self-healing polymers promote the self-healing ability of the self-healing coating even after minor damage, extending the lifespan of the release film. Their optical and electronic properties remain stable even when damaged, ensuring long-term reliability. Using other quantum effect particles, particularly those without a core-shell structure, often reduces the self-healing effect due to particle agglomeration or material instability, resulting in reduced durability and inability to achieve long-term reuse.

[0025] In the present invention, the self-healing polymer, through combination with the molybdenum disulfide layer and the thiol self-assembly molecules, gives the release film the ability to automatically repair itself when it is micro-damaged, while enhancing the durability and wear resistance of the film, effectively reducing the peeling force and extending its service life, making it suitable for long-term and high-frequency application environments.

[0026] This invention significantly reduces the surface energy of the release film by depositing a two-dimensional molybdenum disulfide (MoS2) layer on the surface of a PET substrate, then coating it with a multilayer structure containing thiol self-assembling molecules, quantum effect particles, and a self-healing polymer. This design not only makes the release film easier to remove but also reduces adhesive residue, improving the user experience.

[0027] Molybdenum disulfide (MoS2), a two-dimensional material, possesses excellent mechanical strength, lubricity, and chemical stability. Its lubricating properties further reduce the release film's coefficient of friction and enhance its durability. Furthermore, self-assembled thiol molecules bond to the MoS2 surface, enhancing its overall chemical stability and making it resilient to surface oxidation and degradation in a variety of chemical environments.

[0028] To sum up, the innovation of the present invention lies in the innovative integration of multiple functional materials, combining two-dimensional materials, self-assembling molecules, quantum effect particles and self-healing polymers, creatively achieving a release film with low peel force, self-healing ability and high durability, solving the problems of high peel force, poor durability and insufficient self-healing performance in the prior art.

[0029] In a specific embodiment, the weight percentages of the components constituting the self-healing coating of the present invention are: 85wt%-90wt% of isopropyl alcohol, 0.5wt%-1.0wt% of 1-octanethiol, 2.0wt%-5.0wt% of zinc sulfide-coated cadmium selenide nanoparticles, 0.1wt%-0.5wt% of polyethyleneimine (PEI), and 5.0wt%-8.0wt% of polydimethylsiloxane (PDMS).

[0030] Correspondingly, the low peeling force release film of the above specific embodiment of the present invention can be prepared by the following method.

[0031] (1) PET substrate pretreatment:

[0032] Cleaning and Drying: Thoroughly clean the PET substrate with deionized water and dry it to remove organic matter and dust on the surface, as well as any residual moisture, ensuring the substrate surface is dry. PET substrate thickness range: 25μm to 80μm.

[0033] (2) Molybdenum disulfide (MoS2) deposition:

[0034] Chemical Vapor Deposition (CVD): A uniform thin film of molybdenum disulfide is deposited on the PET substrate via CVD at high temperatures (500-600°C). The MoS2 deposition thickness is preferably 5-15 nm to ensure a low peel force and smooth surface for the release film.

[0035] Cooling: After deposition, cool to room temperature to avoid cracks or stress in the film.

[0036] (3) Preparation of self-repairing coating solution:

[0037] Solvent preparation: In a clean container, first add 85 wt%-90 wt% of isopropyl alcohol (IPA) as a solvent.

[0038] Add 0.5 wt% to 1.0 wt% of thiol self-assembly molecular material (1-octanethiol) into the container and stir until completely dissolved. Control the stirring speed to prevent the generation of bubbles.

[0039] Continue to add 2.0 wt% to 5.0 wt% of quantum effect particles (zinc sulfide coated cadmium selenide) into the container and keep stirring for 30 to 60 minutes.

[0040] 0.1 wt% to 0.5 wt% of polyethyleneimine (PEI) is then added to the container to improve the dispersion stability of the particles. Stirring is continued for 30 to 60 minutes.

[0041] 5.0 wt% to 8.0 wt% of the self-healing polymer (PDMS) was added to the container and stirred for 30 to 60 minutes until the solution was uniform.

[0042] (4) Coating process:

[0043] Spin coating: The prepared solution is poured onto the PET surface that has been deposited with MoS2. Using a spin coating machine, the solution is evenly coated on the MoS2 surface at a high speed (3000 rpm). The thickness of the applied self-healing coating is 10-100 nanometers.

[0044] (5) Drying and curing:

[0045] Low temperature drying: After coating, place the film in a drying oven at 60°C to 80°C for 30-60 minutes to ensure that the solvent is completely evaporated.

[0046] Subsequent curing: Raise the temperature to 120-150°C to further cure the coating for 60-90 minutes to ensure the mechanical properties and durability of the film.

[0047] Parameter detection:

[0048] Surface testing: The release film's peel force, as measured by a peel force tester, is 5-10g / 25mm. This low peel force eliminates the need for silane release agents, demonstrating its suitability for use in the electronics industry. The surface friction coefficient is 0.2-0.3, demonstrating low friction and low adhesion.

[0049] Optical and Mechanical Properties: The film's light transmittance, thickness, tensile strength, and self-healing ability were tested. The tensile strength was 150-180 MPa, and the elongation at break was 100%-120%, demonstrating good strength and ductility. Optical transparency reached 90% to 95% in the visible light band of 500nm to 800nm.

[0050] Stability and Durability: Operates within temperatures between 120°C and 150°C without significant deformation or degradation. Self-healing at room temperature or under heating after minor mechanical damage. Durable over extended use, resists aging or degradation.

[0051] Example 1:

[0052] Raw material composition:

[0053] PET substrate thickness: 25μm; MoS2 layer thickness: 5nm; self-healing coating thickness: 10nm.

[0054] Self-healing coating components: isopropyl alcohol: 85wt%; 1-octanethiol: 0.5wt%; zinc sulfide-coated cadmium selenide nanoparticles: 2wt%; polyethyleneimine (PEI): 0.1wt%; PDMS: 5wt%.

[0055] Preparation conditions:

[0056] CVD deposition temperature: 500°C, time: 30 minutes; coating curing temperature: 120°C, time: 60 minutes.

[0057] Surface peel force tests showed a value of 5g / 25mm, with a coefficient of friction of 0.2, demonstrating low peel force and excellent anti-stick properties. Furthermore, the product boasts a tensile strength of 150MPa and an elongation at break of 100%, demonstrating excellent mechanical strength and flexibility. Its transmittance reaches 95% in the visible light band from 500nm to 800nm, making it particularly suitable for applications requiring high transparency.

[0058] Example 2:

[0059] Raw material composition:

[0060] PET substrate thickness: 50 μm; MoS2 layer thickness: 10 nm; Self-healing coating thickness: 50 nm.

[0061] Self-healing coating components: isopropyl alcohol: 87wt%; 1-octanethiol: 0.7wt%; zinc sulfide-coated cadmium selenide nanoparticles: 3wt%; polyethyleneimine (PEI): 0.3wt%; PDMS: 6wt%.

[0062] Preparation conditions:

[0063] CVD deposition temperature: 550°C, time: 45 minutes; coating curing temperature: 130°C, time: 75 minutes.

[0064] The peel force is 7g / 25mm and the coefficient of friction is 0.25, maintaining a low peel force and good abrasion resistance. Its tensile strength is 165MPa and its elongation at break reaches 110%, demonstrating its excellent mechanical properties and suitability for use under conditions of high mechanical stress. Its light transmittance remains around 90% in the visible light band, meeting the standards required by most industries.

[0065] Example 3:

[0066] Raw material composition:

[0067] PET substrate thickness: 80 μm; MoS2 layer thickness: 15 nm; Self-healing coating thickness: 100 nm.

[0068] Self-healing coating components:

[0069] Isopropyl alcohol: 90 wt %; 1-octanethiol: 1 wt %; zinc sulfide-coated cadmium selenide nanoparticles: 5 wt %; polyethyleneimine (PEI): 0.5 wt %; PDMS: 8 wt %.

[0070] Preparation conditions:

[0071] CVD deposition temperature: 600°C, time: 60 minutes; coating curing temperature: 150°C, time: 90 minutes.

[0072] With a peel force of 10g / 25mm and a coefficient of friction of 0.3, it offers enhanced durability and abrasion resistance. With a tensile strength of 180MPa and an elongation at break of 120%, it exhibits excellent strength and ductility under high loads. Its light transmittance reaches 90%, making it particularly suitable for applications subject to high frequency use or extreme environments.

[0073] Comparative Example 1

[0074] Based on Examples 1-3, zinc sulfide-coated cadmium selenide nanoparticles were replaced with zinc sulfide particles, while keeping other conditions unchanged. Test results showed that the quantum effect of zinc sulfide particles was weak and could not significantly reduce the surface energy, resulting in increased peel force and decreased optical and electronic properties of the film.

[0075] Comparative Example 2

[0076] Based on Examples 1-3, the CVD deposition temperature was lowered from 500°C to 400°C, while other conditions remained unchanged. Test results showed that low-temperature deposition resulted in an incomplete molybdenum disulfide layer structure, poor film crystal quality, decreased film friction coefficient and durability, and an inability to effectively achieve low peel force.

[0077] Comparative Example 3

[0078] Based on Example 3, the PDMS content in the self-healing coating was reduced from 8wt% to 2wt%, while keeping all other conditions unchanged. Test results showed that insufficient PDMS significantly reduced the self-healing effect, preventing the film from repairing itself in time when it sustained minor damage, thus reducing the durability and service life of the release film.

[0079] Comparative Example 4

[0080] Based on Examples 1-3, the thickness of the molybdenum disulfide layer was reduced to 2nm, the thickness of the self-healing coating was increased to 150nm, and the PDMS content was reduced to 3wt%, while other conditions remained unchanged. Test results showed that an overly thin molybdenum disulfide layer resulted in insufficient structural integrity of the membrane, failing to effectively reduce the surface friction coefficient, and the peel force increased to 15g / 25mm. Furthermore, an overly thick self-healing coating compromised the membrane's optical properties, reducing its transmittance to 80%. The self-healing ability was also significantly reduced due to insufficient PDMS content, making it impossible to recover after repeated damage.

[0081] Comparative Example 5

[0082] Based on Examples 1-3, the CVD deposition temperature was increased to 700°C, and the thiol self-assembling molecules in the self-healing coating component were reduced to 0.3wt%, while other conditions remained unchanged. Test results showed that excessively high deposition temperatures led to a decrease in the crystalline quality of the molybdenum disulfide layer, resulting in cracks, an increase in the friction coefficient to 0.5, and a peel force of 20g / 25mm. Furthermore, the reduction in the number of thiol self-assembling molecules resulted in poor surface self-assembly, reduced chemical stability and durability of the film, and increased surface energy, resulting in a shortened service life.

[0083] Comparative Example 6

[0084] Based on Examples 1-3, the substrate was changed to a 100μm-thick polycarbonate (PC), while other conditions remained unchanged. Test results showed that the PC substrate had poor flexibility and low compatibility with the molybdenum disulfide layer, resulting in decreased coating adhesion and an increase in peel force to 25g / 25mm. The increased PC substrate thickness also further reduced the film's transmittance to 70%. At the same time, the tensile strength dropped to 130MPa, and the elongation at break was only 80%, significantly affecting the film's mechanical properties and durability.

[0085] Comparative Example 7

[0086] Based on Examples 1-3, the self-healing coating thickness was reduced to 5nm, the quantum effect particle content was increased to 7wt%, and all other conditions remained unchanged. When the self-healing coating was too thin, it was easily abraded and unable to effectively repair itself upon damage, significantly reducing the durability and self-healing ability of the film. Furthermore, when the quantum effect particle content was too high, particle agglomeration occurred, resulting in poor surface uniformity and an increase in peel force to 18g / 25mm. This compromised optical properties and reduced transmittance to 85%, affecting overall performance.

[0087] In summary, adjusting multiple parameters in the comparative examples above, such as coating thickness, material ratio, and deposition conditions, resulted in a significant decrease in the release film's peel force, friction coefficient, optical clarity, and self-healing ability. In contrast, the present invention, through a rational combination design, effectively controls the peel force, providing excellent durability, self-healing properties, and optical clarity, demonstrating its significant innovation in the field of release films.

[0088] As mentioned above, the quantum effect particles of cadmium selenide coated with zinc sulfide in the present invention can provide excellent optical properties, mechanical strength, low peel force and self-repairing ability. Replacing with other quantum effect particles may lead to a significant decrease in stability, durability, self-repairing and peel force control effects, affecting the overall performance and application range of the release film.

[0089] Those skilled in the art can purchase existing zinc sulfide-coated cadmium selenide for use as the quantum effect particles in the present invention, or can prepare zinc sulfide-coated cadmium selenide suitable for the present invention by the following method.

[0090] Furthermore, the quantum effect particles of zinc sulfide-coated cadmium selenide can be prepared by the following process:

[0091] 1. Preparation of CdSe core:

[0092] Cadmium source: Cadmium oxide (CdO): 0.04-0.07 parts by weight

[0093] Selenium source: Selenium powder (Se): 0.03-0.06 parts by weight

[0094] Ligand: 8-12 parts by weight of octadecene (ODE), 1-4 parts by weight of oleylamine (OLA), 1.5-3 parts by weight of oleic acid (OA)

[0095] Solvent: n-octane (for cleaning): 50-100 parts by weight

[0096] Process steps:

[0097] Step 1:

[0098] In a three-necked flask, add 0.04-0.07 parts by weight of CdO, 1.5-3 parts by weight of oleic acid, and 8-12 parts by weight of octadecene (ODE). Heat to 150°C under a nitrogen atmosphere and react until CdO is completely dissolved to form a Cd oleate solution.

[0099] Step 2:

[0100] 0.03-0.06 parts by weight of selenium powder and 1-4 parts by weight of oleylamine (OLA) were mixed and heated to 120° C. in another flask to form a Se precursor solution.

[0101] Step 3:

[0102] The selenium precursor solution is injected into the Cd oleate solution and the temperature is immediately raised to 300°C. The reaction is maintained for one hour. This process forms CdSe quantum dot cores. After cooling to room temperature using a cooling system, the CdSe cores are then cleaned and precipitated using 50-100 parts by weight of n-octane.

[0103] 2. ZnS shell coating:

[0104] Zinc source: zinc acetate (Zn(OAc)2): 0.08-0.12 parts by weight

[0105] Sulfur source: H2S gas: 0.015-0.03 parts by weight

[0106] Solvent: Isopropyl alcohol: 50-100 parts by weight

[0107] Redispersion solvent: octadecene: 10-15 parts by weight

[0108] Process steps:

[0109] Step 1:

[0110] The cleaned CdSe cores prepared above were redispersed in 10-15 parts by weight of octadecene, heated to 80° C., and maintained in a nitrogen atmosphere.

[0111] Step 2:

[0112] At 80°C, 0.08-0.12 parts by weight of zinc acetate (Zn(OAc)2) was added and stirred for 30-60 minutes to evenly distribute the zinc ions. The temperature was then raised to 100°C to promote the adsorption of Zn.

[0113] Step 3:

[0114] 0.015-0.03 parts by weight of H2S gas is introduced. When H2S reacts with zinc ions to generate ZnS, a ZnS shell is deposited on the surface of the CdSe quantum dots.

[0115] Step 4:

[0116] The reaction was heated for 2 hours to ensure the formation of the ZnS shell (maintaining the temperature at 100° C.), then cooled to room temperature, and the product was washed and separated with 20-50 parts by weight of isopropanol to obtain ZnS@CdSe nanoparticles.

[0117] 5. Cleaning and drying:

[0118] Step 1:

[0119] The prepared ZnS@CdSe nanoparticles were centrifuged and repeatedly washed with 30-50 parts by weight of isopropyl alcohol to remove any unreacted residues.

[0120] Step 2:

[0121] After cleaning, vacuum dry the ZnS@CdSe nanoparticles and store them for future use. Drying temperature: 40°C-60°C; drying time: 4-8 hours; pressure: 0.1 mbar to 0.5 mbar. This ensures efficient and uniform drying while ensuring particle integrity and functionality. Try to keep the temperature below 60°C to avoid thermal damage.

[0122] Notes:

[0123] During the entire synthesis process, nitrogen protection was used to prevent oxidation of CdSe quantum dots.

[0124] Temperature control is crucial to the core-shell structure of quantum dots. The formation of CdSe core requires a high temperature environment, while the coating of ZnS shell is usually carried out at a lower temperature.

[0125] The washing process is important to remove unreacted impurities, precursors, and excess ligands to ensure the purity and dispersion of the final product.

[0126] Through the above steps, ZnS@CdSe nanoparticles with excellent optical and electrical properties can be prepared, while ensuring their stability and uniform dispersion. These nanoparticles can be used for surface functionalization of release films, while also ensuring the optical, electrical properties and durability of core-shell quantum dots.

[0127] Example 4

[0128] In a three-necked flask, 0.05 parts by weight of CdO, 1.5 parts by weight of oleic acid, and 10 parts by weight of octadecene were added and heated to 150°C under nitrogen to form a Cd oleate solution. In another flask, 0.04 parts by weight of selenium powder and 2 parts by weight of oleylamine were mixed and heated to 120°C to form a Se precursor solution. The Se precursor solution was injected into the Cd oleate solution, and the temperature was immediately raised to 300°C. The reaction was maintained for 1 hour. After cooling, the CdSe cores were washed. The CdSe cores were dispersed in 12 parts by weight of octadecene, heated to 80°C, and 0.1 parts by weight of zinc acetate was added and stirred for 30 minutes. 0.02 parts by weight of H2S gas was introduced and the reaction was maintained at 100°C for 2 hours to obtain ZnS@CdSe nanoparticles.

[0129] Test: Particle size: about 8 nm; Optical absorption peak: 520 nm; Luminescence intensity (PL): 80%.

[0130] Example 5

[0131] In a three-necked flask, 0.04 parts by weight of CdO, 1.8 parts by weight of oleic acid, and 9 parts by weight of octadecene were added and heated to 160°C under nitrogen to form a Cd oleate solution. In another flask, 0.05 parts by weight of selenium powder and 2.5 parts by weight of oleylamine were mixed and heated to 125°C to form a Se precursor solution. The Se precursor solution was injected into the Cd oleate solution, and the temperature was immediately raised to 320°C. The reaction was maintained for 1 hour. After cooling, the CdSe cores were washed. The CdSe cores were dispersed in 15 parts by weight of octadecene, heated to 85°C, and 0.12 parts by weight of zinc acetate was added and stirred for 30 minutes. 0.025 parts by weight of H2S gas was then introduced and the reaction was maintained at 105°C for 2 hours to obtain ZnS@CdSe nanoparticles.

[0132] Test: Particle size: about 10 nm; Optical absorption peak: 530 nm; Luminescence intensity (PL): 85%.

[0133] Example 6

[0134] In a three-necked flask, 0.06 parts by weight of CdO, 1.3 parts by weight of oleic acid, and 8 parts by weight of octadecene were added and heated to 140°C under nitrogen to form a Cd oleate solution. In another flask, 0.06 parts by weight of selenium powder and 2 parts by weight of oleylamine were mixed and heated to 130°C to form a Se precursor solution. The Se precursor solution was injected into the Cd oleate solution, and the temperature was immediately raised to 310°C. The reaction was maintained for 1 hour. After cooling, the CdSe cores were washed. The CdSe cores were dispersed in 14 parts by weight of octadecene, heated to 90°C, and 0.15 parts by weight of zinc acetate was added and stirred for 30 minutes. 0.03 parts by weight of H2S gas was introduced, and the reaction was maintained at 110°C for 2 hours to obtain ZnS@CdSe nanoparticles.

[0135] Test: Particle size: about 12 nm; Optical absorption peak: 540 nm; Luminescence intensity (PL): 78%.

[0136] The ZnS@CdSe particles of Examples 4-6 were applied to Examples 1-3, and were replaced with ZnO quantum dots, TiO2 quantum dots, and PbS quantum dots for comparative experiments. The results showed that the quantum effect particles of zinc sulfide-coated cadmium selenide can significantly provide excellent optical properties, mechanical strength, low peeling force, and self-healing ability.

[0137] Those skilled in the art should understand that although the present invention is described in terms of multiple embodiments, not each embodiment contains only one independent technical solution. This description is provided for clarity only. Those skilled in the art should understand the description as a whole and consider the technical solutions involved in each embodiment as being combinable into different embodiments to understand the scope of protection of the present invention.

[0138] The above description is only an illustrative embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principle of the present invention shall fall within the scope of protection of the present invention.

Claims

1. A low peel force release film, with polyethylene terephthalate (PET) as a base material; characterized in that: A two-dimensional molybdenum disulfide (MoS2) layer is deposited on the surface of a PET substrate by chemical vapor deposition; a self-repairing coating is coated on the surface of the molybdenum disulfide (MoS2) layer, and the self-repairing coating is solidified by the following components: isopropyl alcohol; thiol self-assembly molecules; quantum effect particles; Polyethyleneimine (PEI) and self-healing polymers.

2. The release film according to claim 1, wherein The thickness of the molybdenum disulfide layer is 5-15 nanometers.

3. The release film according to claim 1, wherein The thickness of the self-repairing coating is 10-100 nanometers.

4. The release film according to claim 1, wherein The thickness of the PET substrate is 25 μm to 80 μm.

5. The release film according to claim 1, wherein The weight percentages of the components constituting the self-healing coating are: 85wt%-90wt% of isopropyl alcohol, 0.5wt%-1.0wt% of 1-octanethiol, 2.0wt%-5.0wt% of zinc sulfide-coated cadmium selenide nanoparticles, 0.1wt%-0.5wt% of polyethyleneimine (PEI), and 5.0wt%-8.0wt% of polydimethylsiloxane (PDMS).

6. The release film according to claim 5, wherein The zinc sulfide-coated cadmium selenide nanoparticles are prepared from the following raw materials in parts by weight: 0.04-0.07 parts by weight of cadmium oxide; 0.03-0.06 parts by weight of selenium powder; 18-27 parts by weight of octadecene; 1-4 parts by weight of oleylamine; 1.5-3 parts by weight of oleic acid; 50-100 parts by weight of n-octane; 0.08-0.12 parts by weight of zinc acetate; 0.015-0.03 parts by weight of H2S gas; and 50-100 parts by weight of isopropyl alcohol.

7. The method for preparing a low-peel force release film according to any one of claims 1 to 6, comprising the following steps: using polyethylene terephthalate (PET) as a substrate, first cleaning the surface of the PET substrate; depositing a molybdenum disulfide thin film on the PET substrate by CVD at 500° C. to 600° C., and cooling to room temperature; preparing a self-repairing coating solution; coating the prepared self-repairing coating solution on the surface of the molybdenum disulfide layer; After coating, the film is placed in a drying oven and dried at 60°C to 80°C for 30-60 minutes; the temperature is increased to 120°C to 150°C to further cure the coating for 60-90 minutes.

8. The release film according to claim 7, wherein The self-healing coating solution is prepared by the following steps: first adding 85wt%-90wt% of isopropanol to a clean container; adding 0.5wt%-1.0wt% of 1-octanethiol to the container and stirring until completely dissolved; continuing to add 2.0wt%-5.0wt% of zinc sulfide-coated cadmium selenide to the container and stirring for 30-60 minutes; continuing to add 0.1wt%-0.5wt% of polyethyleneimine to the container and stirring for 30-60 minutes; continuing to add 5.0wt%-8.0wt% of PDMS to the container and stirring for 30-60 minutes.

9. The release film according to claim 7, wherein: The zinc sulfide-coated cadmium selenide nanoparticles are prepared by the following steps: adding 0.04-0.07 parts by weight of CdO, 1.5-3 parts by weight of oleic acid and 8-12 parts by weight of octadecene (ODE) to a three-necked flask, heating to 150° C. under a nitrogen environment, and reacting until CdO is completely dissolved to form a Cd oleate solution; mixing 0.03-0.06 parts by weight of selenium powder with 1-4 parts by weight of oleylamine (OLA), and heating to 120° C. in another flask to form a Se precursor solution; injecting the selenium precursor solution into the Cd oleate solution, and immediately raising the temperature to 300° C., maintaining the reaction for 1 hour, cooling to room temperature, and then using 50-100 parts by weight of n-octane solvent to clean and precipitate the CdSe core; The prepared cleaned CdSe cores are redispersed in 10-15 parts by weight of octadecene, heated to 80° C., and maintained in a nitrogen environment; 0.08-0.12 parts by weight of zinc acetate (Zn(OAc)2) are added at 80° C. and stirred for 30-60 minutes; 0.015-0.03 parts by weight of H2S gas are introduced; the temperature is maintained at 100° C. and the reaction is continued for 2 hours, after which the temperature is lowered to room temperature, and the product is washed and separated with 20-50 parts by weight of isopropanol to obtain ZnS@CdSe nanoparticles; the prepared ZnS@CdSe nanoparticles are centrifuged and repeatedly washed with 30-50 parts by weight of isopropanol; the washed ZnS@CdSe nanoparticles are vacuum dried and stored for later use.

10. The release film according to claim 9, wherein The vacuum drying temperature of ZnS@CdSe nanoparticles is 40°C-60°C; the drying time is 4-8 hours; and the pressure range is 0.1 mbar to 0.5 mbar.