Active diluent containing dynamic intercalated carbamate bond as well as preparation method and application of active diluent

Abstract

The invention discloses a preparation method and application of a reactive diluent containing a dynamic intercalated urethane bond. The preparation method comprises the following steps: removing moisture from a monomer containing acetoacetate bonds and double bonds and polyether amine; adding polyether amine into the dehydrated monomer containing the acetoacetate bond and the double bond while stirring in a closed environment, and reacting for 2-4 hours at the temperature of 20-25 DEG C; and adding an excessive amount of water absorbent into the obtained product, and carrying out suction filtration to obtain the reactive diluent containing the dynamic intercalated carbamate bond. The obtained reactive diluent is low in viscosity, rich in raw material source, free of heating in the production process, capable of being generated through a one-step method, simple in process, low in cost and suitable for industrial production. The UV-LED (Ultraviolet-Light Emitting Diode) light-cured resin prepared by applying the active diluent containing the dynamic intercalated urethane bond has good degradability, mechanical property and reprocessing property.

Description

Technical Field

[0001] This invention relates to a diluent, specifically to an active diluent containing dynamically intercalated urethane bonds, its preparation method, and its application, belonging to the field of photocurable materials technology. Background Technology

[0002] Photocurable resins, as functional resin systems that cure by initiating polymerization reactions with ultraviolet or visible light, have been widely used in coatings, 3D printing, electronic packaging, and bonding in recent years. Compared with traditional thermosetting or solvent-based resins, photocurable systems have significant advantages. First, they cure quickly, typically within seconds to minutes, greatly improving production efficiency, making them particularly suitable for applications with high time and efficiency requirements. Second, photocuring is a room-temperature curing process, requiring no high-temperature heating, thus resulting in low energy consumption, environmental friendliness, and good compatibility with heat-sensitive substrates. Third, photocurable resins have high crosslinking density and excellent mechanical properties, achieving good abrasion resistance, chemical resistance, and dimensional stability. Furthermore, these systems typically use solvent-free or low-solvent formulations, emitting almost no volatile organic compounds (VOCs), aligning with the trend towards green and environmentally friendly development. In recent years, with the development of photoinitiators and functional reactive diluents, the shortcomings of photocurable resins as coatings in terms of adhesion, flexibility, and weather resistance have been gradually improved. Overall, UV-curable resins, with their high efficiency, energy saving, and environmental friendliness, exhibit unique advantages among many resin systems, making them an important research and application hotspot in the field of materials.

[0003] Photocurable resins are mainly composed of oligomers, photoinitiators, reactive diluents, and additives. The prepolymer forms the core of the resin, determining the basic properties of the cured material, such as strength, chemical resistance, and flexibility. The photoinitiator decomposes under light to generate free radicals or cations, initiating the polymerization reaction. Additives improve workability and surface quality. Reactive diluents play a crucial role in the system. They are low-viscosity monomers containing polymerizable double bonds, significantly reducing system viscosity and improving processing flow during coating, spraying, or printing. They also participate in crosslinking with the prepolymer during curing, becoming an important component of the cured network. By selecting different types of reactive diluents, the properties of the cured product can be flexibly controlled: multifunctional diluents help increase crosslinking density and hardness, while monofunctional diluents help reduce shrinkage and enhance toughness. Fluorine- or silicon-containing diluents can also improve weather resistance and surface properties. Therefore, reactive diluents are not merely simple diluents, but rather an important means of controlling the overall performance of photocurable resins.

[0004] Introducing dynamic bonds into UV-curable resins can endow them with degradable, adaptive, repairable, and reprocessable properties. This effectively overcomes the brittleness and irreversibility issues caused by the high crosslinking density of traditional UV-curable resins, providing new possibilities for their application in high-performance coatings, flexible electronics, and sustainable materials. Reactive diluents participate in the crosslinking process within the UV-curable resin, introducing dynamic bonds into the resin itself, thereby endowing the UV-curable resin with the properties inherent in dynamic bonds.

[0005] Currently, there are published documents on technologies that introduce dynamic bonds into polyfunctional acrylates containing dynamic bonds. For example, prior art 1, "Spessa A, Bongiovanni R, Vitale A. A novel disulfide-containing monomer for photoinitiator-free self-healable photocured coatings[J]. Progress in Organic Coatings, 2024, 187: 108098," discloses the synthesis of difunctional acrylates containing dynamic disulfide bonds using 2-hydroxyethyl disulfide (HEDS) and 2-acryloyloxyethyl isocyanate (AOI). These acrylates have the characteristics of reactive diluents, but the reversibility of the disulfide bonds is highly dependent on the redox environment. Their breaking and reconstruction must be regulated by oxidants or reducing agents, and they are prone to breaking at high temperatures, resulting in insufficient thermal stability.

[0006] Existing technology 2, "Ballester-Bayarri L, Pascal A, Ayestaran J, et al. 3Dprinting of vinylogous urethane-based methacrylic covalent adaptable networks by vat photopolymerization[J]. ACS Applied Polymer Materials, 2024, 6(5):2594-2603", discloses the use of tris(2-aminoethyl)amine (TREN) and (2-acetylacetoxy)ethyl methacrylate (AAEM) to form polyfunctional acrylates with dynamic intercalation bonds for 3D printing. However, the primary amine used in this prior art 2 is the trifunctional TREN, which has three amino groups. This will generate more cross-linking reactions and easily form polymers with larger molecular weights. The resulting product has more intercalation bonds and forms more hydrogen bonds. Moreover, the TREN molecule is relatively rigid, and the product generated after the reaction is relatively stiff, resulting in excessively high viscosity of the synthesized monomer. It is necessary to use a large amount of solvent and common acrylate monomers for dilution before use. Although it involves polyfunctional acrylates with dynamic bonds, for the above reasons, the product cannot be used for dilution. Summary of the Invention

[0007] To address the problems existing in the prior art, this invention provides an active diluent containing dynamically intercalated urethane bonds with low viscosity, abundant raw material sources, no heating required during production, a one-step production process, and a simple and low-cost method, as well as its preparation method. The UV-LED photocurable resin prepared using the active diluent containing dynamically intercalated urethane bonds of this invention has good degradability, mechanical properties, and reprocessing properties.

[0008] Another object of the present invention is to provide the application of the active diluent containing dynamically intercalated urethane bonds in the preparation of UV-LED photocurable resins.

[0009] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0010] An active diluent containing dynamically intercalated urethane bonds has the following structural formula: or or ;

[0011] R1 is R2 is ;

[0012] R3 is ;

[0013] In the R1 group, i = 2.5-68, where i represents the number of structural replication units of the unit within the parentheses;

[0014] In the R2 group, a+b+c=5.3-85, where a, b, and c represent the number of structural replication units of the unit within the parentheses;

[0015] In the R3 group, q = 9-39, p+l = 3.6-6, where p, q, and l represent the number of structural replication units of the unit within the parentheses.

[0016] The R1 group is attached to the N atom of the secondary amine group on both sides, the R2 group is attached to the N atom of the secondary amine group on all three sides, and the R3 group is attached to the N atom of the secondary amine group on both sides.

[0017] The preparation method of the active diluent containing dynamically intercalated urethane bonds is as follows: A monomer containing acetoacetate bonds and double bonds and a polyetheramine are dehydrated; the dehydrated monomer containing acetoacetate bonds and double bonds is added to the polyetheramine under stirring in a closed environment, and reacted at 20-25℃ for 2-4 hours; an excess of desiccant is added to the obtained product, and the mixture is filtered to obtain the active diluent containing dynamically intercalated urethane bonds; the amount of the monomer containing acetoacetate bonds and double bonds and the polyetheramine is added according to a molar ratio of primary amine to acetoacetate bonds of 1:0.9-1.1.

[0018] To further achieve the objectives of this invention, preferably, the monomer containing ethyl acetoacetate and a double bond is selected from one or more of ethyl acetoacetate methacrylate and ethyl acetoacetate acrylate.

[0019] Preferably, the polyetheramine is selected from one or more of polyetheramine D230, polyetheramine D400, polyetheramine D2000, polyetheramine D4000, polyetheramine T403, polyetheramine T3000, polyetheramine T5000, polyetheramine ED600, polyetheramine ED900 and polyetheramine ED2003.

[0020] Preferably, the absorbent is selected from one or more of anhydrous magnesium sulfate, anhydrous sodium sulfate, anhydrous calcium sulfate, and anhydrous potassium carbonate.

[0021] Preferably, the removal of moisture from the monomers containing acetoacetate bonds and double bonds and the polyetheramine is achieved by adding molecular sieves.

[0022] The stirring speed is 100-200 rpm;

[0023] The enclosed environment is a sealed container with a stirring paddle.

[0024] Preferably, the temperature of 20-25℃ is controlled by a water bath;

[0025] The aforementioned filtration is used to remove the water-containing absorbent.

[0026] Preferably, the viscosity of the obtained reactive diluent containing dynamic intercalated urethane bonds is 300-650 mPa·s.

[0027] Application of the active diluent containing dynamic intercalated urethane bonds in the preparation of UV-LED photocurable resin: 30%-70% acrylate oligomer, 20%-60% active diluent containing dynamic intercalated urethane bonds and 1%-10% photoinitiator are added to a reaction vessel and mixed and stirred for 1-2 hours by mass percentage to obtain UV-LED photocurable resin.

[0028] Preferably, the acrylate oligomer is selected from one of epoxy acrylate, polyester acrylate, polyether acrylate, polyurethane acrylate, unsaturated polyester, organosilicon oligomer, and acrylate-esterified acrylate;

[0029] The photoinitiator is one or more of 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO), 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone (photoinitiator 369), 1-hydroxycyclohexylphenyl ketone (photoinitiator 184), and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator 819).

[0030] The stirring speed is 200-300 rpm.

[0031] Compared with the prior art, the main advantages of the present invention are as follows:

[0032] (1) The polyfunctional acrylate monomer obtained by the present invention has a low viscosity and can be used as an active diluent for UV curing materials to enhance the mechanical properties of UV curing materials. Because it contains dynamic intercalated urethane bonds, it can give the resin degradable and processable properties.

[0033] (2) The present invention first uses various polyetheramines with different structures and acrylates containing acetoacetate bonds as raw materials, and prepares an active diluent containing dynamic intercalated urethane bonds through the enamylation reaction of primary amines and β-keto ester bonds. Only a small amount of water in the product needs to be removed.

[0034] (3) By controlling the length and functionality of the polyetheramine containing the dynamic intercalated urethane bond reactive diluent, the present invention can obtain reactive diluents containing dynamic intercalated urethane bonds with different molecular weights and different functionalities. Moreover, the prepared reactive diluents have fast photocuring speed and low volatility, further expanding the potential application scenarios of the material in the field of polymer materials.

[0035] (4) The preparation method of the active diluent containing dynamic intercalated carbamate bonds of the present invention has a wide range of raw material sources and a simple synthesis method. At the same time, since the enamine reaction is fast and the reaction conditions are mild, no heating or cooling is required, and the product only needs to be separated from water, which greatly reduces the production cost of enterprises and has obvious cost advantages.

[0036] (5) The reactive diluent of the present invention can be photocured with different acrylate oligomers. The UV-LED photocurable resin prepared by using the reactive diluent of the present invention containing dynamic intercalated urethane bonds has good degradability, mechanical properties and reprocessing properties.

[0037] (6) The active diluent of the present invention contains an intercalated urethane bond, which is a dynamic bond. It can undergo intercalated amine-imine tautomerism / amine exchange reaction under various conditions such as water, acid, heat or amine exchange, and has a wide range of applications. Attached Figure Description

[0038] Figure 1 The image shows the 1H NMR spectrum of the active diluent with dynamically inserted urethane bonds in Example 1.

[0039] Figure 2 The stress-strain curve of the resin prepared for the application example is shown.

[0040] Figure 3 The images show the appearance of the photocurable resin prepared in Example 1 before and after degradation; the left side of the image shows the appearance before degradation, and the right side shows the appearance after degradation.

[0041] Figure 4 The degradation mechanism reaction diagram is shown for the photocurable resin prepared in Example 1.

[0042] Figure 5 Images of products obtained by reprocessing the photocurable resin prepared in Example 1. Detailed Implementation

[0043] To better understand the present invention, it will be further described below with reference to the accompanying drawings and specific embodiments. However, the implementation of the present invention is not limited thereto. The described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0044] Introducing dynamic bonds into photocurable resins can improve their properties, giving them degradability, self-adaptive properties, repairability, and reprocessability. Compared to disulfide bonds, the reversibility of intercalated alkene bonds is independent of redox environments, being more controlled by factors such as temperature, light, or pH. This makes intercalated alkene bonds more flexible in applications under various conditions, and they typically exhibit better thermal stability, maintaining their structure at higher temperatures, making them suitable for materials requiring high-temperature processing or applications.

[0045] The aforementioned function of intercalated ene bonds is based on the ene intercalation reaction, a reversible addition reaction that allows for bond breaking and reformation under certain conditions. However, existing technologies struggle to apply intercalated ene bonds to reactive diluents, possibly because such reactions are generally used to generate macromolecular polymers to improve the mechanical properties of the products. This invention discovers that the reaction of ethyl acetoacetate with monomers containing double bonds and polyetheramines allows the products to be used as reactive diluents, effectively solving the problem of excessively high product viscosity.

[0046] Therefore, the preparation method of the reactive diluent containing dynamically intercalated acetoacetate bonds of the present invention involves removing moisture from monomers containing acetoacetate bonds and double bonds and polyetheramine; adding polyetheramine to the dehydrated monomers containing acetoacetate bonds and double bonds in a closed environment under stirring, and reacting at a temperature of 20-25°C for 2-4 hours; adding excess desiccant to the obtained product, filtering, and obtaining the reactive diluent containing dynamically intercalated acetoacetate bonds; the amount of monomers containing acetoacetate bonds and double bonds and polyetheramine added is based on a molar ratio of primary amine to acetoacetate bonds of 1:0.9-1.1. Removing moisture from the monomers containing acetoacetate bonds and double bonds and polyetheramine is very important and can be achieved using molecular sieves. Appropriate temperature and time are also necessary conditions, and controlling the molar ratio of raw materials is also essential. As for the monomers containing acetoacetate bonds and double bonds that meet the requirements of the present invention, ethyl acetoacetate and ethyl acetoacetate are preferably one or more of them. There are many options for polyetheramines, with one or more of the following being preferred: polyetheramine D230, polyetheramine D400, polyetheramine D2000, polyetheramine D4000, polyetheramine T403, polyetheramine T3000, polyetheramine T5000, polyetheramine ED600, polyetheramine ED900, and polyetheramine ED2003.

[0047] For the purpose of drying, the desiccant can be one or more of anhydrous magnesium sulfate, anhydrous sodium sulfate, anhydrous calcium sulfate, and anhydrous potassium carbonate.

[0048] In the above preparation method, the stirring speed, the sealed environment, and the temperature control are conventional processes in the art. The preferred stirring speed is 100-200 rpm; the sealed environment is a sealed container with a stirring paddle; and the temperature is 20-25℃, which is achieved through water control. The purpose of filtration is to remove the water-containing absorbent.

[0049] The viscosity of the reactive diluent containing dynamic intercalated urethane bonds obtained by the above method is 300-650 mPa·s.

[0050] This invention introduces a suitable number of intercalated olefin bonds into an active diluent, which can impart rearrangement properties to the material's network structure during subsequent service stages. Thus, the resulting cured product can achieve self-healing through dynamic bond recombination when subjected to microcracks or external damage, thereby extending its service life. Simultaneously, the intercalated olefin dynamic bonds can also alleviate curing shrinkage and internal stress to a certain extent, improving the material's dimensional stability; and through the dynamic equilibrium of amines, the resin can possess reprocessable and biodegradable properties. Specifically, introducing dynamic intercalated olefin bonds into polyfunctional acrylates, and by introducing flexible polyether long chains into polyfunctional acrylates with low viscosity, not only enriches the molecular design methods of photocuring systems but also expands their application advantages in the fields of smart, self-healing, and recyclable materials.

[0051] The reactive diluent containing dynamically intercalated urethane bonds obtained by the preparation method of this invention has the following structural formula: or or ;

[0052] R1 is R2 is ;

[0053] R3 is ;

[0054] In the R1 group, i = 2.5-68; in the R2 group, a+b+c = 5.3-85; and in the R3 group, q = 9-39 and p+l = 3.6-6.

[0055] Although the reactive diluent containing dynamically intercalated urethane bonds of this invention has three structural formulas, they all contain common specific groups, and the preparation methods are consistent, with essentially the same performance and function. The products of the three structural formulas are specifically demonstrated in Examples 1-5, and their performance tests also prove their basic consistency. The prepared reactive diluent has low viscosity and can act as a diluent. When added in a certain proportion, it can improve the thermal stability, mechanical properties, and thermomechanical properties of the cured film. In particular, it exhibits high reactivity under ultraviolet light irradiation and also possesses a good balance between hardness and flexibility. Compared with existing known polyfunctional acrylates, the surface shrinkage of the coating after photocuring crosslinking is very small. Blending this reactive diluent with oligomers in different proportions can give the resulting photocurable resin reprocessable and biodegradable properties.

[0056] Unless otherwise stated, the raw materials, reactions, and post-processing methods mentioned in the examples are all commercially available raw materials and technical methods well known to those skilled in the art.

[0057] Example 1

[0058] A method for preparing an active diluent containing dynamically intercalated urethane bonds includes the following steps:

[0059] S1: Add ethyl acetoacetate methacrylate and polyetheramine D230 to a molecular sieve to remove the water inside; add 40g of ethyl acetoacetate methacrylate to a sealed container with a stirrer, stir at 100rpm, immerse the sealed container in a water bath to cool the temperature rise caused by the intercalation reaction, and add 21.473g of polyetheramine D230 dropwise using a constant pressure dropping funnel, and react at 20℃ for 2h.

[0060] S2: Add excess anhydrous magnesium sulfate to the product of step S1, stir to remove the water produced by the reaction, and then remove the water-containing desiccant anhydrous magnesium sulfate by filtration to obtain an active diluent containing dynamic intercalated urethane bonds; the yield was tested to be 98% and the viscosity was 300 mPa·s, and it was named AD230A.

[0061] Structural characterization: The 1H NMR spectrum of the reactive diluent containing dynamically intercalated urethane bonds prepared in Example 1 was measured using a Bruker AVANCE 500 MHz nuclear magnetic resonance spectrometer. Deuterated chloroform solvent (CDCL3) was used as the deuteration reagent, and 1H NMR spectra were acquired.

[0062] Figure 1The 1H NMR spectrum of the active diluent with the dynamic intercalated urethane bond of Example 1 is shown. As can be seen from the figure, 8.52 ppm is the hydrogen on the -NH- of the intercalated amine, 6.13 ppm and 5.57 ppm are the hydrogen on the double bond -CH=CH2-, 4.44 ppm is the hydrogen on -C=CH-C-, and 4.33 ppm and 4.28 ppm are the hydrogen on -CH2-CH2-. Therefore, it can be shown that the structure containing the dynamic intercalated urethane bond is consistent with the target.

[0063] The above NMR spectra indicate that the obtained reactive diluent containing dynamically intercalated urethane bonds has the following structure: .

[0064] Example 2

[0065] A method for preparing an active diluent containing dynamically intercalated urethane bonds includes the following steps:

[0066] S1: Add molecular sieves to ethyl acetoacetate methacrylate and polyetheramine D400 to remove internal moisture; add 40g of ethyl acetoacetate methacrylate to a sealed container with a stirrer, stir at 200rpm, immerse the sealed container in a water bath to cool the temperature rise caused by the intercalation reaction, and add 40.15g of polyetheramine D400 dropwise using a constant pressure dropping funnel, and react at 25℃ for 3h.

[0067] S2: Add excess anhydrous potassium sulfate to the product of step S1, stir to remove the water produced by the reaction, and then remove the water-containing desiccant by filtration to obtain an active diluent containing dynamic intercalated urethane bonds. The yield was tested to be 96% and the viscosity was 350 mPa·s. It was named AD400A.

[0068] similar Figure 1 The NMR spectrum test confirmed that the reactive diluent containing dynamically intercalated urethane bonds obtained in this embodiment has the following structure: .

[0069] Example 3

[0070] A method for preparing an active diluent containing dynamically intercalated urethane bonds includes the following steps:

[0071] S1: Add molecular sieves to ethyl acetoacetate methacrylate and polyetheramine D2000 to remove excess water; add 40g of ethyl acetoacetate methacrylate to a sealed container with a stirrer, stir at 150rpm, immerse the sealed container in a water bath to cool the temperature rise caused by the intercalation reaction, and add 186.72g of polyetheramine D2000 dropwise using a constant pressure dropping funnel, and react at 25℃ for 4h.

[0072] S2: Add excess anhydrous potassium sulfate to the product of step S1, stir to remove the water produced by the reaction, and then remove the water-containing desiccant by filtration to obtain an active diluent containing dynamic intercalated urethane bonds with a yield of 97% and a viscosity of 370 mPa·s, named AD2000A.

[0073] similar Figure 1 The NMR spectrum test confirmed that the reactive diluent containing dynamically intercalated urethane bonds obtained in this embodiment has the following structure: .

[0074] Example 4

[0075] A method for preparing an active diluent containing dynamically intercalated urethane bonds includes the following steps:

[0076] S1: Add molecular sieves to ethyl acetoacetate methacrylate and polyetheramine T403 to remove internal moisture; add 40g of ethyl acetoacetate methacrylate to a sealed container with a stirrer, stir at 150rpm, immerse the sealed container in a water bath to cool the temperature rise caused by the intercalation reaction, and add 27.38g of polyetheramine T403 dropwise using a constant pressure dropping funnel, and react at 23℃ for 3h.

[0077] S2: Add excess anhydrous sodium sulfate to the product of step S1, stir to remove the water produced by the reaction, and then remove the water-containing desiccant by vacuum filtration to obtain an active diluent containing dynamic intercalated urethane bonds. The yield was tested to be 96% and the viscosity was 550 mPa·s. It was named AT403A.

[0078] x+y+z=5.3.

[0079] Example 5

[0080] A method for preparing an active diluent containing dynamically intercalated urethane bonds includes the following steps:

[0081] S1: Add molecular sieves to ethyl acetoacetate methacrylate and polyetheramine ED600 to remove internal moisture; add 40g of ethyl acetoacetate methacrylate to a sealed container with a stirrer, stir at 120rpm, immerse the sealed container in a water bath to cool the temperature rise caused by the intercalation reaction, and add 56.02g of polyetheramine ED600 dropwise using a constant pressure dropping funnel, and react at 21℃ for 2h.

[0082] S2: Add excess anhydrous sodium sulfate to the product of step S1, stir to remove the water produced by the reaction, and then remove the water-containing desiccant by filtration to obtain an active diluent containing dynamic intercalated urethane bonds. The yield was 96% and the viscosity was 650 mPa·s. It was named AED600A.

[0083] y=9, x+z=3.6.

[0084] Application Examples

[0085] This application example provides a photocurable resin prepared from an active diluent containing dynamically intercalated urethane bonds synthesized in Example 1.

[0086] A UV-curable resin comprising, as described in Examples 1 and 4, a reactive diluent containing dynamically intercalated urethane bonds, an oligomer, and a photoinitiator, wherein the UV-curable resin is divided into two components with the following weight percentages:

[0087] Table 1. Examples of applications of photocurable resins

[0088] Table 2 Examples of Application of Photocurable Resins

[0089] The raw materials in the above proportions were put into a reaction vessel and stirred at 50°C for 2 hours to obtain UV-LED light-curing resin.

[0090] Test case

[0091] The UV-LED curable resin obtained for the corresponding use case was tested.

[0092] Test method:

[0093] The resin obtained from the application examples was used to prepare a resin film with a thickness of 0.4 mm, and then the mechanical properties were tested according to the following methods.

[0094] Mechanical property testing: Measured using a SANS universal testing machine at room temperature. Cured samples were cut into dumbbell-shaped strips and measured at a tensile speed of 10 mm / min and a gauge length of 1.2 mm.

[0095] Degradation performance test: 100 mg of sample was immersed in 5 ml of ethanol containing 0.5 g ethylamine at room temperature, the degradation time was recorded, and the degradation rate was calculated.

[0096] Processing performance: UV-LED light-curing resin is cut into small pieces and hot-pressed at 150℃ and 15MPa pressure.

[0097] Table 3 Resin performance test results

[0098] Figure 2 The stress-strain curves of the resins prepared in the application examples are shown. As can be seen from the figure, the tensile strength of the UV-cured resin obtained in Application Example 1 is 7.18 MPa, and the elongation at break is 177.29%. The tensile strength of the UV-cured resin in Application Example 2 is 39.78 MPa, and the elongation at break is 22.92%.

[0099] Figure 3 The images show the appearance of the photocurable resin prepared in Application Example 1 before and after degradation; wherein, Figure 3 The left side shows the appearance of the photocurable resin prepared using the formulation of Example 1 before degradation; Figure 3 The right side shows the appearance of the photocurable resin prepared in Application Example 1 after degradation. As can be seen from the figure, the photocurable resin prepared in Application Example 1 can be completely dissolved in ethanol solution after treatment at 60°C and under amine conditions for a certain time, indicating that the photocurable resin prepared in Application Example 1 can degrade, demonstrating that the introduction of intercalated alkene dynamic bonds endows the resin with good amine degradation performance.

[0100] Figure 4 The degradation mechanism of the photocurable resin prepared in Application Example 1 is illustrated. The raw materials for the photocurable resin prepared in Application Example 1 mainly consist of the reactive diluent containing intercalated olefin bonds and oligomers of the present invention. The resulting photocurable resin is obtained by crosslinking and curing the oligomers and the reactive diluent. Figure 4 The diagram shows that when the photocurable resin prepared in Application Example 1 is placed in an ethanol solution containing ethylamine, dynamic amine exchange occurs. The ethylamine displaces the polyetheramine from the resin, and the resin without crosslinking points becomes an oligomer, while the polyetheramine dissolves in the solution. The three substances at the bottom of the figure, from left to right, are the acrylate oligomer depolymerized after being replaced by ethylamine, polyetheramine D230, and the acrylate oligomer depolymerized after being replaced by ethylamine, illustrating the achievement of degradation.

[0101] Figure 5 An image showing the reprocessable photocurable resin prepared in Application Example 1 is shown. Figure 5 The left side shows a schematic diagram of the photocurable resin obtained in Application Example 1 being cut into small pieces. Figure 5 The image on the right shows a single film formed after the photocured resin, cut into small pieces, is hot-pressed at 150°C and 15MPa. Reprocessing refers to the process where the resin, after being broken down into various small pieces, can reconnect due to the presence of dynamic bonds, thus reforming into a whole. The image illustrates that the resin contains dynamic intercalated enamine bonds, which, after undergoing dynamic exchange at high temperatures and breaking, can reconnect. This demonstrates that the reactive diluent containing dynamic intercalated enamine bonds imparts excellent reprocessability to the resin.

[0102] The test results above show that the UV-LED resin prepared in the application example contains intercalated olefin dynamic bonds, which can undergo a primary amine exchange reaction under conditions containing small molecule primary amines, giving the resin good degradability. The reaction mechanism is as follows: Figure 4 As shown, the degradation rate in Application Example 1 can reach 3.33 mg·ml. -1 ·h -1 And by Figure 2 The photocurable resin prepared in the application examples exhibits certain mechanical properties, making it suitable for application. The photocurable resin prepared in Application Example 1 has a tensile strength of 7.18 MPa and an elongation at break of 177.29%. Furthermore, the fact that the photocurable resin, when cut into small pieces and hot-pressed at 150°C and 15 MPa, can be re-pressed into a single film demonstrates its good processability.

[0103] In summary, the reactive diluent containing dynamically intercalated olefin bonds provided by this invention has abundant raw materials, a simple process, and a designable structure. It can be applied to polymer materials and can be photocured with different acrylate oligomers, giving the resin degradable properties and good mechanical properties. Its synthesis method is of great significance for the development of photocurable resin materials.

[0104] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A reactive diluent containing dynamically intercalated urethane bonds, characterized in that... It has the following structural formula: or or ; R1 is R2 is ; R3 is ; In the R1 group, i = 2.5-68; in the R2 group, a+b+c = 5.3-85; and in the R3 group, q = 9-39 and p+l = 3.6-6.

2. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds as described in claim 1, characterized in that: The monomers containing acetoacetate bonds and double bonds and polyetheramine are dehydrated; the dehydrated monomers containing acetoacetate bonds and double bonds are added to polyetheramine under stirring in a closed environment and reacted at 20-25℃ for 2-4 hours; excess desiccant is added to the obtained product, and the mixture is filtered to obtain an active diluent containing dynamic intercalated urethane bonds; the amount of monomers containing acetoacetate bonds and double bonds and polyetheramine is added according to the molar ratio of primary amine to acetoacetate bonds of 1:0.9-1.

1.

3. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that: The monomer containing ethyl acetoacetate and a double bond is selected from one or more of ethyl acetoacetate methacrylate and ethyl acetoacetate acrylate.

4. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that: The polyetheramine is selected from one or more of polyetheramine D230, polyetheramine D400, polyetheramine D2000, polyetheramine D4000, polyetheramine T403, polyetheramine T3000, polyetheramine T5000, polyetheramine ED600, polyetheramine ED900 and polyetheramine ED2003.

5. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that: The absorbent is selected from one or more of anhydrous magnesium sulfate, anhydrous sodium sulfate, anhydrous calcium sulfate, and anhydrous potassium carbonate.

6. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that: The removal of moisture from the monomers containing acetoacetate bonds and double bonds and the polyetheramine is achieved by adding molecular sieves; The stirring speed is 100-200 rpm; The enclosed environment is a sealed container with a stirring paddle.

7. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that, The temperature of 20-25℃ is achieved through water bath control. The aforementioned filtration is used to remove the water-containing absorbent.

8. The method for preparing the reactive diluent containing dynamically intercalated urethane bonds according to claim 2, characterized in that, The viscosity of the obtained reactive diluent containing dynamic intercalated urethane bonds is 300-650 mPa·s.

9. The application of the reactive diluent containing dynamically intercalated urethane bonds as described in claim 1 in the preparation of UV-LED photocurable resins, characterized in that, By weight percentage, 30%-70% of acrylate oligomer, 20%-60% of reactive diluent containing dynamic intercalated urethane bonds, and 1%-10% of photoinitiator are added to a reaction vessel and mixed and stirred for 1-2 hours to obtain UV-LED curable resin.

10. The application of the reactive diluent containing dynamically intercalated urethane bonds according to claim 9 in the preparation of UV-LED photocurable resin, characterized in that, The acrylate oligomers mentioned are selected from one of epoxy acrylates, polyester acrylates, polyether acrylates, polyurethane acrylates, unsaturated polyesters, organosilicon oligomers, and acrylate-esterified acrylates; The photoinitiator is one or more of 2,4,6-trimethylbenzoyl diphenylphosphine oxide (TPO), 2-phenylbenzyl-2-dimethylamine-1-(4-morpholinobenzylphenyl)butanone (photoinitiator 369), 1-hydroxycyclohexylphenyl ketone (photoinitiator 184), and phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (photoinitiator 819); The stirring speed is 200-300 rpm.

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