A rosin-based epoxy vitrimer with fluorescent properties, its preparation method and its application

Abstract

This invention discloses a rosin-based epoxy vitrimer with fluorescent properties, its preparation method, and its applications. The structural formula of the fluorescent rosin-based epoxy vitrimer is as follows: This invention uses renewable biomass resources rosin and malic acid as raw materials. Hydrogenated acrylic rosin is ring-opened with epoxy resin under solvent-free conditions to obtain rosin-based epoxy resin. The rosin-based epoxy resin is then ring-opened with malic acid under catalyst-free and solvent-free conditions to obtain the vitrimer material. The vitrimer material of this invention has good metal adhesion properties, with an adhesion strength of up to 24.8 MPa, which is higher than some traditional epoxy resin adhesives. It exhibits shape memory and self-healing properties, possessing triple shape memory properties based on Tg and Tv, and has good self-healing ability when heated without a catalyst. It can also be recycled through two environmentally friendly strategies: physical recycling and chemical degradation recycling. In addition, HAR-EP-MA also has unique fluorescent properties, emitting fluorescence at around 500 nm under ultraviolet light excitation.

Description

Technical Field

[0001] This invention relates to a rosin-based epoxy vitrimer with fluorescent properties, its preparation method and its application, belonging to the field of chemical materials technology. Background Technology

[0002] Traditional polymer materials can be divided into thermosetting polymers and thermoplastic polymers. Thermoplastic polymers are characterized by melting upon heating and hardening upon cooling, thus generally possessing the advantage of reusability. However, their mechanical properties and thermal stability are generally poor, significantly limiting their applications. Thermosetting resins, due to their excellent mechanical properties and solvent resistance, have a wide range of applications across various industries. However, the irreversible three-dimensional permanent network structure in cured thermosetting resins leads to a loss of reprocessing properties, resulting in resource waste. Furthermore, thermosetting resins and their curing agents are mostly petroleum-based products, causing environmental pollution problems with long-term use. Gradually replacing petroleum-based resources with bio-based resources, introducing reversible dynamic covalent bonds, and preparing bio-based "Vitrimer" resins that possess the reprocessability of thermoplastic materials and the excellent mechanical properties of thermosetting materials can largely solve the above problems.

[0003] Currently, most of the raw materials used to prepare epoxy vitrimer are petrochemical-based products, which does not conform to the concept of sustainable development, and the preparation process requires a lot of solvents and catalysts. Summary of the Invention

[0004] The purpose of this invention is to provide a rosin-based epoxy vitrimer with fluorescent properties, its preparation method, and its applications. This invention involves a solvent-free and catalyst-free process where renewable biomass rosin and epoxy resin undergo a ring-opening reaction with an epoxy protic acid to obtain a rosin-based epoxy resin. This resin, along with a dicarboxylic acid, then undergoes a further ring-opening reaction to prepare a rosin-based epoxy vitrimer material with self-healing, reprocessing, and chemical degradation properties. This solves the problem of the difficulty in recycling and reusing traditional thermosetting polymer materials, while simultaneously achieving controlled recycling of thermosetting materials under mild conditions.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0006] A rosin-based epoxy vitrimer with fluorescent properties has the following structural formula:

[0007]

[0008] Where n = 0, 0.2, 0.4, 0.5, 2.3, 4.7; the wavy line represents the omission of repeating units.

[0009] The above-mentioned method for preparing rosin-based epoxy vitrimer with fluorescent properties first involves reacting hydrogenated acrylic rosin (HAR) with bisphenol A type epoxy resin (EP). n Acidic ring-opening under the catalysis of triphenylphosphine yields rosin-based epoxy resin (HAR-EP). n Then, rosin-based epoxy resin (HAR-EP) n HAR-EP was synthesized by acidic ring-opening of malic acid (MA) under solvent-free and catalyst-free conditions. n -MA x No solvent is required during the entire reaction process.

[0010] The fluorescent rosin-based epoxy vitrimer is abbreviated as HAR-EP. n -MA x x = carboxyl group content / epoxy group content.

[0011] Rosin-based epoxy resin (HAR-EP) n The structural formula of ) is:

[0012]

[0013] Where n = 0, 0.2, 0.4, 0.5, 2.3, 4.7.

[0014] The aforementioned bisphenol A type epoxy resin is at least one of bisphenol A diglycidyl ether, E-51 epoxy resin, E-44 epoxy resin, E-42 epoxy resin, E-20 epoxy resin, or E-12 epoxy resin.

[0015] To further ensure the overall performance of rosin-based epoxy Vitrimer, E-51 epoxy resin is preferred as the bisphenol A type epoxy resin.

[0016] To balance product performance and yield, the mass ratio of hydrogenated acrylic rosin to bisphenol A epoxy resin is 1:(1.5–8); the mass ratio of malic acid (MA) to rosin-based epoxy resin (HAR-EP) is... n The mass ratio is 1:(8~15);

[0017] As a specific implementation scheme, the preparation method of the above-mentioned rosin-based epoxy vitrimer with fluorescent properties includes the following steps:

[0018] 1) Hydrogenated acrylic rosin, bisphenol A epoxy resin, and triphenylphosphine are reacted at a temperature of 130–160°C with stirring until the acid value is less than 1 mg KOH / g, to obtain HAR-EP. nThe molar ratio of -COOH in hydrogenated acrylic rosin to epoxy group in bisphenol A epoxy resin is 1:(2-2.1); triphenylphosphine is used as a catalyst, and the amount of triphenylphosphine used is 1-3g / 500g of total mass, and the total mass is the sum of the masses of hydrogenated acrylic rosin and bisphenol A epoxy resin.

[0019] 2) Add malic acid (MA) to HAR-EP at a temperature of 120–135°C. n After stirring and reacting in the molten material, a rosin-based epoxy vitrimer prepolymer was obtained. This prepolymer was then poured into a mold while hot and cured at high temperature to obtain HAE-EP. n -MA x Among them, HAR-EP n The molar ratio of the epoxy group in the middle to the -COOH group in malic acid (MA) is 1:(0.6~1.0), preferably 1:1.

[0020] In step 1) above, the carboxyl group in the rosin structure is an active modification site. Using epoxy resin as a raw material, rosin-based epoxy resin can be prepared by undergoing an acidic ring-opening reaction with rosin under solvent-free conditions, triphenylphosphine catalysis, and a temperature of 130–160°C. A more preferable molar ratio of -COOH in hydrogenated acrylic rosin to epoxy groups in bisphenol A type epoxy resin is 1:2, which results in a higher grafting rate of hydrogenated acrylic rosin onto the rosin-based epoxy resin and facilitates the ring-opening reaction.

[0021] In step 2) above, the material used for the mold can be selected from polytetrafluoroethylene, silicone, or glass. Preferably, the mold is made of polytetrafluoroethylene, so that the rosin-based epoxy Vitrimer material can be easily demolded after complete curing.

[0022] To ensure complete curing, a step-by-step curing method is adopted. In step 2), the high-temperature curing is carried out sequentially at 120-130℃ for 1-2 hours, at 140-150℃ for 1-2 hours, and at 160-170℃ for 1-2 hours. In step 1), the stirring speed is 100-300 rpm and the reaction time is 1-2 hours. In step 2), the heating rate is 2-4℃ / min, the stirring speed is 100-300 rpm, and the reaction time is 10-30 minutes.

[0023] This application presents a rosin-based epoxy vitrimer with fluorescent properties that can be recycled and reused, and can also be completely degraded. Recycling method: The recycled rosin-based epoxy vitrimer is ground into powder and hot-pressed at 170–180℃ and 8–10 MPa for 20–30 min to obtain rosin-based epoxy vitrimer again. Degradation method: The recycled rosin-based epoxy vitrimer is ground into powder, placed in anhydrous ethanol, and reacted in a pressure reactor at 170–180℃ and 2–3 MPa for 6–8 h. The powder is completely dissolved in the anhydrous ethanol, completing the degradation, and the degradation solution can be used to obtain rosin-based epoxy vitrimer material again.

[0024] During the above degradation process, 15–25 mL of anhydrous ethanol is used for every 1 g of rosin-based epoxy Vitrimer.

[0025] The aforementioned rosin-based epoxy vitrimer with fluorescent properties can be used as an adhesive.

[0026] One specific implementation method when used as an adhesive is to place the rosin-based epoxy Vitrimer prepolymer between two substrates and apply it at a temperature of 65-95℃ and a pressure of 15-25 N / m. 2 Under hot pressing conditions for 1–3 minutes, the substrates are cured at high temperature, and the two substrates are stably bonded together. The high-temperature curing is performed sequentially at 120–130°C for 1–2 hours, at 140–150°C for 1–2 hours, and at 160–170°C for 1–2 hours.

[0027] The aforementioned rosin-based epoxy Vitrimer material with fluorescent properties can also be used in fluorescent anti-counterfeiting and / or information transmission, emitting a blue light of about 500nm when excited by ultraviolet light.

[0028] When applied to information transmission, it can be used to manufacture supports, correctors, deformation mechanisms, controllers, or sensors.

[0029] Any techniques not mentioned in this invention are based on existing technologies.

[0030] Compared with the prior art, the present invention achieves the following beneficial effects:

[0031] (1) This invention uses renewable biomass resources rosin and malic acid as raw materials. Rosin undergoes a ring-opening reaction with epoxy resin under solvent-free conditions to obtain rosin-based epoxy resin. Then, the rosin-based epoxy resin undergoes a ring-opening reaction with malic acid under catalyst-free and solvent-free conditions to obtain Vitrimer material. The preparation process is green and environmentally friendly, the raw materials used are inexpensive, and the preparation cost is low. At the same time, it can reduce the dependence on non-renewable petroleum resources and realize the recycling of thermosetting materials.

[0032] (2) The rosin-based epoxy Vitrimer material prepared by this invention contains dynamically reversible β-hydroxy ester bonds and has the characteristics of thermal stimulation and alcohol degradation, which makes Vitrimer exhibit self-healing, reprocessing and physical and chemical recycling capabilities, thus broadening the research field of Vitrimer.

[0033] (3) The rosin-based epoxy Vitrimer material prepared by the present invention can be applied to adhesives, and the bonding strength of stainless steel can reach 24 MPa, which is higher than that of traditional epoxy resin.

[0034] (4) The rosin-based epoxy Vitrimer material prepared by the present invention has strong fluorescent properties. Under ultraviolet light excitation, it can emit blue light of about 500nm and the quantum yield can reach 10.78%. It can be applied to fluorescent anti-counterfeiting, which broadens the application value of rosin and realizes the high-value sustainable utilization of rosin.

[0035] (5) The rosin-based epoxy Vitrimer material prepared by the invention has triple shape memory characteristics based on Tg and Tv, high glass transition temperature and good mechanical properties. Attached Figure Description

[0036] Figure 1 For HAR-EP 0.2 -MA x Tensile strength;

[0037] Figure 2 For HAR-EP 0.2 -MA x Lap shear strength when bonding stainless steel;

[0038] Figure 3 HAREP under different heating times 0.2 -MA x The healing status;

[0039] Figure 4 It is a triple shape memory for HAR-EP0.2-MA1.0. Detailed Implementation

[0040] The present invention will be further described in detail below with reference to the embodiments. The embodiments are for illustrative purposes only and do not limit the invention in any way. Unless otherwise specified, the raw materials and reagents used in the embodiments are conventional products that can be obtained commercially; experimental methods that do not specify specific conditions in the embodiments are generally performed under conventional conditions in the art or according to the conditions recommended by the manufacturer.

[0041] Unless otherwise specified, the process was carried out at room temperature (15–25°C); the stirring speed was 200 r / min.

[0042] Example 1

[0043] Hydrogenated acrylic rosin (Shenzhen Siten Industrial Co., Ltd.) and E-51 epoxy resin (Shanghai McLean Biochemical Technology Co., Ltd.) were mixed at a molar ratio of -COOH in the hydrogenated acrylic rosin to epoxy groups in the bisphenol E-51 epoxy resin of 1:2. An acidic ring-opening reaction was carried out under stirring at 150℃ and with triphenylphosphine catalysis. The mass of triphenylphosphine was 1 g / 500 g of total mass. The reaction progress was accurately monitored every half hour using 0.1 mol / L KOH standard solution. The reaction was stopped when the acid value of the mixed system was less than 1 mg KOH / g, taking 1.5 h. After cooling, the disappearance of the epoxy and carboxyl peaks and the appearance of the ester characteristic peak were observed by Fourier transform infrared spectroscopy (FT-IR). Further structural characterization by nuclear magnetic resonance (NMR) confirmed that the rosin-based epoxy resin HAR-EP... 0.2 Successfully synthesized.

[0044] The prepared rosin-based epoxy resin HAR-EP 0.2 The mixture was melted at 130°C, and malic acid was then added. After stirring at 130°C for 20 minutes, a homogeneous rosin-based epoxy Vitrimer prepolymer was obtained. While still hot, the prepolymer was poured into a polytetrafluoroethylene mold and cured sequentially at 130°C for 2 hours, 150°C for 2 hours, and 170°C for 2 hours. After natural cooling to room temperature, the rosin-based epoxy Vitrimer material, denoted as HAR-EP, was obtained. 0.2 -MA 1.0 The molar ratio of epoxy groups in rosin-based epoxy resin to carboxyl groups in malic acid is 1:1.0; the heating rate during curing is 3℃ / min.

[0045] Tests showed that the glass transition temperature of the rosin-based epoxy Vitrimer material is 102℃.

[0046] The stress-strain curve of rosin-based epoxy Vitrimer material is as follows: Figure 1 As shown, by Figure 1 As can be seen, due to the rigid skeleton of rosin, the material exhibits excellent mechanical properties, with a stress of 28.2 MPa, which can meet the basic mechanical performance requirements.

[0047] Adhesion performance testing: The adhesion performance of rosin-based epoxy Vitrimer material was measured using a microcomputer-controlled electronic tensile testing machine at a tensile speed of 5 mm / min. -1Each type of sample was tested 5 times. A uniformly mixed rosin-based epoxy Vitrimer prepolymer was placed between two identical stainless steel substrates (100mm × 25mm × 1.6mm). The coverage area of ​​the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 25mm × 12.5mm, and the thickness of the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 0.2mm. The test was conducted at a temperature of 65℃ and a pressure of 15N / m. 2 Under hot pressing conditions for 2 minutes, the two substrates were fixed together at both ends with paperclips. Curing was then completed after sequentially curing at 130℃ for 2 hours, 150℃ for 2 hours, and 170℃ for 2 hours. The measured bond strength was as follows: Figure 2 As shown, it can reach 24.8 MPa.

[0048] Self-healing experiment: After scratching the rosin-based epoxy Vitrimer material with a blade (scratch width 225 μm, depth 0.2 mm), a glass slide was placed on the surface and placed on a hot stage at 130℃. The scratches on the material surface gradually healed within 0–15 minutes. Figure 3 As shown, the healing rate reached 46.7%, indicating that the prepared rosin-based epoxy Vitrimer material has highly efficient self-healing properties.

[0049] Shape memory experiment: Change the shape of the spline, such as Figure 4 As shown, HAR-EP 0.2 -MA 1.0 The material is bent into an "S" shape at 120°C (above Tg) and cooled to 25°C to obtain the final "S" shape. When the temperature is reheated to 120°C, the temporary "S" shape reverts to a permanent rectangle, indicating that HAR-EP... 0.2 -MA 1.0 The vitreous body possesses shape memory properties based on Tg. Furthermore, to demonstrate HAR-EP... 0.2 -MA 1.0 The vitreous body's triple shape memory, HAR-EP 0.2 -MA 1.0 The material was bent into an "O" shape at 180°C, stored for 30 minutes for topological freezing transformation, and then cooled to 25°C to obtain a permanent "O" shape. Subsequently, HAR-EP... 0.2 -MA 1.0 It deforms into a spiral shape at 120°C and cools to 25°C. When reheated to 100°C, the spiral shape returns to a permanent "O" shape, and DTER occurs only when heated to 180°C, HAR-EP. 0.2 -MA 1.0 Only then can it be restored to a rectangular shape. This indicates that HAR-EP 0.2 -MA 1.0 The vitreous body has triple shape memory.

[0050] Recycling Experiments: (a) Physical Recycling: Rosin-based epoxy Vitrimer material was ground into powder with a particle size of less than 100 μm and hot-pressed for 30 min at 180 °C and 10 MPa. The rosin-based epoxy Vitrimer material was then molded into complete samples. The mechanical property recovery rate of the recycled samples reached 64%, indicating that the prepared rosin-based epoxy Vitrimer material has reprocessable properties. (b) Chemical Recycling: 1 g of rosin-based epoxy Vitrimer material powder with a particle size of less than 100 μm was placed in 20 mL of anhydrous ethanol and degraded in a pressure reactor at 180 °C and 3 MPa for 8 h. The solid was completely dissolved in the solution, indicating that the prepared rosin-based epoxy Vitrimer material can be chemically degraded and can be re-cured using the degradation solution to obtain rosin-based epoxy Vitrimer material.

[0051] Fluorescence properties: The fluorescence properties of HAR-EP-MA were tested using a fluorescence spectrometer. Under 390 nm UV excitation, HAR-EP... 0.2 -MA 1.0 It emits fluorescence at around 500nm.

[0052] Example 2

[0053] Hydrogenated acrylic rosin (Shenzhen Siten Industrial Co., Ltd.) and E-51 epoxy resin (Shanghai McLean Biochemical Technology Co., Ltd.) were mixed at a molar ratio of -COOH in the hydrogenated acrylic rosin to epoxy groups in the bisphenol E-51 epoxy resin of 1:2. An acidic ring-opening reaction was carried out under stirring at 150℃ and with triphenylphosphine catalysis. The mass of triphenylphosphine was 1 g / 500 g of total mass. The reaction progress was accurately monitored every half hour using 0.1 mol / L KOH standard solution. The reaction was stopped when the acid value of the mixed system was less than 1 mg KOH / g, taking 1.5 h. After cooling, the disappearance of epoxy and carboxyl peaks and the appearance of ester characteristic peaks were observed by Fourier transform infrared spectroscopy (FT-IR). Further structural characterization by nuclear magnetic resonance (NMR) confirmed that the rosin-based epoxy resin HAR-EP... 0.2 Successfully synthesized.

[0054] The prepared rosin-based epoxy resin HAR-EP 0.2 The mixture was melted at 130°C, and malic acid was then added. After stirring at 130°C for 20 minutes, a homogeneous rosin-based epoxy Vitrimer prepolymer was obtained. While still hot, the prepolymer was poured into a polytetrafluoroethylene mold and cured sequentially at 130°C for 2 hours, 150°C for 2 hours, and 170°C for 2 hours. After natural cooling to room temperature, the rosin-based epoxy Vitrimer material, denoted as HAR-EP, was obtained. 0.2 -MA 0.8The molar ratio of epoxy groups in rosin-based epoxy resin to carboxyl groups in malic acid is 1:0.8; the heating rate during curing is 3℃ / min.

[0055] Tests showed that the glass transition temperature of the rosin-based epoxy Vitrimer material is 100℃.

[0056] The stress-strain curve of rosin-based epoxy Vitrimer material is as follows: Figure 1 As shown, by Figure 1 As can be seen, due to the rigid skeleton of rosin, the material exhibits excellent mechanical properties, showing a stress of 22.7 MPa, which can meet the basic mechanical performance requirements.

[0057] Adhesion performance testing: The adhesion performance of rosin-based epoxy Vitrimer material was measured using a microcomputer-controlled electronic tensile testing machine at a tensile speed of 5 mm / min. -1 Each type of sample was tested 5 times. A uniformly mixed rosin-based epoxy Vitrimer prepolymer was placed between two identical stainless steel substrates (100mm × 25mm × 1.6mm). The coverage area of ​​the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 25mm × 12.5mm, and the thickness of the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 0.2mm. The test was conducted at a temperature of 65℃ and a pressure of 15N / m. 2 Under hot pressing conditions for 2 minutes, the two substrates were fixed together at both ends with paperclips. Curing was then completed after sequentially curing at 130℃ for 2 hours, 150℃ for 2 hours, and 170℃ for 2 hours. The measured bond strength was as follows: Figure 2 As shown, it can reach 20.8 MPa.

[0058] Self-healing experiment: After scratching the rosin-based epoxy Vitrimer material with a blade (scratch width 240 μm, depth 0.2 mm), a glass slide was placed on the surface and placed on a hot stage at 130°C. The scratches on the material surface gradually healed within 0–15 minutes. Figure 3 As shown, the healing rate reached 43.8%, indicating that the prepared rosin-based epoxy Vitrimer material has highly efficient self-healing properties.

[0059] Shape memory experiment: changing the shape of a spline, HAR-EP 0.2 -MA 0.8 The material is bent into an "S" shape at 120°C (above Tg) and cooled to 25°C to obtain the final "S" shape. When the temperature is reheated to 120°C, the temporary "S" shape reverts to a permanent rectangle, indicating that HAR-EP... 0.2 -MA 0.8 The vitreous body possesses shape memory properties based on Tg. Furthermore, to demonstrate HAR-EP... 0.2 -MA0.8 The vitreous body's triple shape memory, HAR-EP 0.2 -MA 0.8 The material was bent into an "O" shape at 180°C, stored for 30 minutes for topological freezing transformation, and then cooled to 25°C to obtain a permanent "O" shape. Subsequently, HAR-EP... 0.2 -MA 0.8 It deforms into a spiral shape at 120°C and cools to 25°C. When reheated to 100°C, the spiral shape returns to a permanent "O" shape, and DTER occurs only when heated to 180°C, HAR-EP. 0.2 -MA 0.8 Only then can it be restored to a rectangular shape. This indicates that HAR-EP 0.2 -MA 0.8 The vitreous body has triple shape memory.

[0060] Recycling Experiments: (a) Physical Recycling: Rosin-based epoxy Vitrimer material was ground into powder with a particle size of less than 100 μm and hot-pressed for 30 min at 180 °C and 10 MPa. The rosin-based epoxy Vitrimer material was then molded into complete samples. The mechanical property recovery rate of the recycled samples reached 58%, indicating that the prepared rosin-based epoxy Vitrimer material has reprocessable properties. (b) Chemical Recycling: 1 g of rosin-based epoxy Vitrimer material powder with a particle size of less than 100 μm was placed in 20 mL of anhydrous ethanol and degraded in a pressure reactor at 180 °C and 3 MPa for 8 h. The solid was completely dissolved in the solution, indicating that the prepared rosin-based epoxy Vitrimer material can be chemically degraded and can be re-cured using the degradation solution to obtain rosin-based epoxy Vitrimer material.

[0061] Fluorescence properties: The fluorescence properties of HAR-EP-MA were tested using a fluorescence spectrometer. Under 390 nm UV excitation, HAR-EP... 0.2 -MA 1.0 It can emit fluorescence at around 500nm.

[0062] Example 3

[0063] Hydrogenated acrylic rosin (Shenzhen Siten Industrial Co., Ltd.) and E-51 epoxy resin (Shanghai McLean Biochemical Technology Co., Ltd.) were mixed at a molar ratio of -COOH in the hydrogenated acrylic rosin to epoxy groups in the bisphenol E-51 epoxy resin of 1:2. An acidic ring-opening reaction was carried out under stirring at 150℃ and with triphenylphosphine catalysis. The mass of triphenylphosphine was 1 g / 500 g of total mass. The reaction progress was accurately monitored every half hour using 0.1 mol / L KOH standard solution. The reaction was stopped when the acid value of the mixed system was less than 1 mg KOH / g, taking 1.5 h. After cooling, the disappearance of epoxy and carboxyl peaks and the appearance of ester characteristic peaks were observed by Fourier transform infrared spectroscopy (FT-IR). Further structural characterization by nuclear magnetic resonance (NMR) confirmed that the rosin-based epoxy resin HAR-EP... 0.2 Successfully synthesized.

[0064] The prepared rosin-based epoxy resin HAR-EP 0.2 The mixture was melted at 130°C, and malic acid was then added. After stirring at 130°C for 20 minutes, a homogeneous rosin-based epoxy Vitrimer prepolymer was obtained. While still hot, the prepolymer was poured into a polytetrafluoroethylene mold and cured sequentially at 130°C for 2 hours, 150°C for 2 hours, and 170°C for 2 hours. After natural cooling to room temperature, the rosin-based epoxy Vitrimer material, denoted as HAR-EP, was obtained. 0.2 -MA 0.6 The molar ratio of epoxy groups in rosin-based epoxy resin to carboxyl groups in malic acid is 1:0.6; the heating rate during curing is 3℃ / min.

[0065] Tests showed that the glass transition temperature of the rosin-based epoxy Vitrimer material is 95℃.

[0066] The stress-strain curve of rosin-based epoxy Vitrimer material is as follows: Figure 1 As shown, by Figure 1 As can be seen, due to the rigid skeleton of rosin, the material exhibits excellent mechanical properties, showing a stress of 21.4 MPa, which can meet the basic mechanical performance requirements.

[0067] Adhesion performance testing: The adhesion performance of rosin-based epoxy Vitrimer material was measured using a microcomputer-controlled electronic tensile testing machine at a tensile speed of 5 mm / min. -1Each type of sample was tested 5 times. A uniformly mixed rosin-based epoxy Vitrimer prepolymer was placed between two identical stainless steel substrates (100mm × 25mm × 1.6mm). The coverage area of ​​the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 25mm × 12.5mm, and the thickness of the uniformly mixed rosin-based epoxy Vitrimer prepolymer was 0.2mm. The test was conducted at a temperature of 65℃ and a pressure of 15N / m. 2 Under hot pressing conditions for 2 minutes, the two substrates were fixed together at both ends with paperclips. Curing was then completed after sequentially curing at 130℃ for 2 hours, 150℃ for 2 hours, and 170℃ for 2 hours. The measured bond strength was as follows: Figure 2 As shown, it can reach 14.2 MPa.

[0068] Self-healing experiment: After scratching the rosin-based epoxy Vitrimer material with a blade (scratch width 175μm, depth 0.2mm), a glass slide was placed on the surface and placed on a hot stage at 130℃. The scratches on the material surface gradually healed within 0–15 minutes. Figure 3 As shown, the healing rate reached 31.4%, indicating that the prepared rosin-based epoxy Vitrimer material has highly efficient self-healing properties.

[0069] Shape memory experiment: changing the shape of a spline, HAR-EP 0.2 -MA 0.8 The material is bent into an "S" shape at 120°C (above Tg) and cooled to 25°C to obtain the final "S" shape. When the temperature is reheated to 120°C, the temporary "S" shape reverts to a permanent rectangle, indicating that HAR-EP... 0.2 -MA 0.8 The vitreous body possesses shape memory properties based on Tg. Furthermore, to demonstrate HAR-EP... 0.2 -MA 0.8 The vitreous body's triple shape memory, HAR-EP 0.2 -MA 0.8 The material was bent into an "O" shape at 180°C, stored for 30 minutes for topological freezing transformation, and then cooled to 25°C to obtain a permanent "O" shape. Subsequently, HAR-EP... 0.2 -MA 0.8 It deforms into a spiral shape at 120°C and cools to 25°C. When reheated to 100°C, the spiral shape returns to a permanent "O" shape, and DTER occurs only when heated to 180°C, HAR-EP. 0.2 -MA 0.8 Only then can it be restored to a rectangular shape. This indicates that HAR-EP 0.2 -MA 0.8 The vitreous body has three shape memories.

[0070] Recycling Experiments: (a) Physical Recycling: Rosin-based epoxy Vitrimer material was ground into powder with a particle size of less than 100 μm and hot-pressed for 30 min at 180 °C and 10 MPa. The rosin-based epoxy Vitrimer material was then molded into complete samples. The mechanical property recovery rate of the recycled samples reached 50%, indicating that the prepared rosin-based epoxy Vitrimer material has reprocessable properties. (b) Chemical Recycling: 1 g of rosin-based epoxy Vitrimer material powder with a particle size of less than 100 μm was placed in 20 mL of anhydrous ethanol and degraded in a pressure reactor at 180 °C and 3 MPa for 8 h. The solid was completely dissolved in the solution, indicating that the prepared rosin-based epoxy Vitrimer material can be chemically degraded and can be cured again using the degradation solution to obtain rosin-based epoxy Vitrimer material.

[0071] Fluorescence properties: The fluorescence properties of HAR-EP-MA were tested using a fluorescence spectrometer. Under 390 nm UV excitation, HAR-EP... 0.2 -MA 1.0 It can emit fluorescence at around 500nm.

Claims

1. The use of a rosin-based epoxy vitrimer with fluorescent properties, characterized in that: It is used in fluorescent anti-counterfeiting and / or information transmission; the rosin-based epoxy vitrimer with fluorescent properties has triple shape memory characteristics and emits 500 nm blue light when excited by ultraviolet light; A method for preparing a rosin-based epoxy vitrimer with fluorescent properties involves ring-opening a rosin-based epoxy resin with malic acid under solvent-free and catalyst-free conditions. The rosin-based epoxy resin is prepared by ring-opening a hydrogenated acrylic rosin with a bisphenol A type epoxy resin under solvent-free conditions. The specific preparation process includes the following steps: 1) Hydrogenated acrylic rosin, bisphenol A type epoxy resin, and triphenylphosphine are stirred and reacted at a temperature of 130~160℃ until the acid value is less than 1mgKOH / g to obtain rosin-based epoxy resin; wherein, the molar ratio of -COOH in hydrogenated acrylic rosin to epoxy group in bisphenol A type epoxy resin is 1:(2~2.1); the mass of triphenylphosphine is 1~3g / 500g total mass; wherein, the total mass is the sum of the mass of hydrogenated acrylic rosin and bisphenol A type epoxy resin; 2) Malic acid is added to the molten rosin-based epoxy resin at a temperature of 120~135℃. After stirring and reacting, rosin-based epoxy Vitrimer prepolymer is obtained. It is poured into a mold while hot and cured at high temperature to obtain rosin-based epoxy Vitrimer with fluorescent properties. The molar ratio of epoxy groups in rosin-based epoxy resin to -COOH in malic acid is 1:(0.6~1.0). The bisphenol A type epoxy resin uses E-51 epoxy resin.

2. The use as described in claim 1, characterized in that: In step 2), the high-temperature curing is performed sequentially at 120~130℃ for 1~2h, at 140~150℃ for 1~2h, and at 160~170℃ for 1~2h.

3. The use as described in claim 1 or 2, characterized in that: The heating rate in step 2) is approximately 2-4°C / min, the stirring speed is 100-300 rpm, and the reaction time is 10-30 min.

4. A method for reprocessing rosin-based epoxy vitrimer with fluorescent properties, characterized in that: A method for preparing a rosin-based epoxy vitrimer with fluorescent properties involves ring-opening a rosin-based epoxy resin with malic acid under solvent-free and catalyst-free conditions. The rosin-based epoxy resin is prepared by ring-opening a hydrogenated acrylic rosin with a bisphenol A type epoxy resin under solvent-free conditions. The specific preparation process includes the following steps: 1) Hydrogenated acrylic rosin, bisphenol A type epoxy resin, and triphenylphosphine are stirred and reacted at a temperature of 130~160℃ until the acid value is less than 1mgKOH / g to obtain rosin-based epoxy resin; wherein, the molar ratio of -COOH in hydrogenated acrylic rosin to epoxy group in bisphenol A type epoxy resin is 1:(2~2.1); the mass of triphenylphosphine is 1~3g / 500g total mass; wherein, the total mass is the sum of the mass of hydrogenated acrylic rosin and bisphenol A type epoxy resin; 2) Malic acid is added to the molten rosin-based epoxy resin at a temperature of 120~135℃. After stirring and reacting, rosin-based epoxy Vitrimer prepolymer is obtained. It is poured into a mold while hot and cured at high temperature to obtain rosin-based epoxy Vitrimer with fluorescent properties. The molar ratio of epoxy groups in rosin-based epoxy resin to -COOH in malic acid is 1:(0.6~1.0). Bisphenol A type epoxy resin uses E-51 epoxy resin; A reprocessing method for rosin-based epoxy vitrimer with fluorescent properties includes recycling and degradation. The recycling method involves grinding the recycled rosin-based epoxy vitrimer into powder and hot-pressing it for 20-30 minutes at 170-180℃ and 8-10MPa to obtain rosin-based epoxy vitrimer again. The degradation method involves grinding the recycled rosin-based epoxy vitrimer into powder, placing it in anhydrous ethanol, and reacting it in a pressure reactor at 170-180℃ and 2-3MPa for 6-8 hours. The powder is completely dissolved in the anhydrous ethanol, completing the degradation, and the degradation solution can be used to obtain rosin-based epoxy vitrimer material again.

5. The use of a rosin-based epoxy vitrimer with fluorescent properties, characterized in that: Used as an adhesive; A method for preparing a rosin-based epoxy vitrimer with fluorescent properties involves ring-opening a rosin-based epoxy resin with malic acid under solvent-free and catalyst-free conditions. The rosin-based epoxy resin is prepared by ring-opening a hydrogenated acrylic rosin with a bisphenol A type epoxy resin under solvent-free conditions. The specific preparation process includes the following steps: 1) Hydrogenated acrylic rosin, bisphenol A type epoxy resin, and triphenylphosphine are stirred and reacted at a temperature of 130~160℃ until the acid value is less than 1mgKOH / g to obtain rosin-based epoxy resin; wherein, the molar ratio of -COOH in hydrogenated acrylic rosin to epoxy group in bisphenol A type epoxy resin is 1:(2~2.1); the mass of triphenylphosphine is 1~3g / 500g total mass; wherein, the total mass is the sum of the mass of hydrogenated acrylic rosin and bisphenol A type epoxy resin; 2) Malic acid is added to the molten rosin-based epoxy resin at a temperature of 120~135℃. After stirring and reacting, rosin-based epoxy Vitrimer prepolymer is obtained. It is poured into a mold while hot and cured at high temperature to obtain rosin-based epoxy Vitrimer with fluorescent properties. The molar ratio of epoxy groups in rosin-based epoxy resin to -COOH in malic acid is 1:(0.6~1.0). The bisphenol A type epoxy resin uses E-51 epoxy resin.

6. The use as described in claim 5, characterized in that: Rosin-based epoxy Vitrimer prepolymer is placed between two substrates at a temperature of 65-95℃ and a pressure of 15-25 N / m. 2 Under hot pressing conditions for 1-3 minutes, the substrates are cured at high temperature, and the two substrates are stably bonded together. The high-temperature curing is performed sequentially at 120-130℃ for 1-2 hours, at 140-150℃ for 1-2 hours, and at 160-170℃ for 1-2 hours.

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