A biomass-recyclable shape memory epoxy resin, its monomer and preparation method

Abstract

The present invention discloses a biomass recyclable shape memory epoxy resin, its monomer and preparation method. Using biomass tyrosol and bisphenolic acid as raw materials, an intermediate is obtained through a heating reaction; the intermediate and epichlorohydrin are heated and reacted to obtain a bisphenolic acid epoxy monomer; and the bisphenolic acid epoxy monomer is cured to obtain a recyclable biomass epoxy resin with shape memory function. Compared with the prior art, the epoxy resin of the present invention has excellent thermal properties and high tensile strength. The epoxy resin obtained by the method of the present invention can have its original shape permanently changed as needed, overcoming the defect that existing biomass epoxy cannot be processed again after forming, and realizing the recovery function under heating stimulation conditions. The excellent thermal properties and mechanical properties also greatly expand the scope of application of the shape memory polymer. At the same time, the epoxy resin of the present invention also has self-healing, degradable and weldable properties.

Description

Technical Field

[0001] The present invention relates to a biomass epoxy monomer, a recyclable shape memory resin based on the biomass epoxy monomer and a preparation method thereof, belonging to the technical field of functional polymer materials. Background Art

[0002] Shape memory polymers (SMPs) are a class of stimulus-responsive polymers that can change and fix their shapes under certain conditions; subsequently, through external stimuli such as heat, electricity, light, chemical induction, etc., the polymers can be made to recover their original shapes. Therefore, SMPs have important applications in many fields, especially when they are used as deployment components and structures, enabling the complex, large-scale, and high-volume assembly of devices. High performance and greenness are the two main directions of material research and development, and the same is true for the research and development of functional polymer materials. High heat resistance and high mechanical strength are typical indicators of high-performance green polymer materials, while most of the currently developed SMPs have a low glass transition temperature (Tg) and are not suitable for fields with high requirements for heat resistance. Moreover, their tensile strength is relatively low.

[0003] In particular, most SMPs cannot be reshaped or recycled due to their irreversible three-dimensional network cross-linked structure. The large accumulation of discarded functional polymer materials will cause irreversible environmental pollution, which is one of the key problems restricting their future applications and development. The prior art synthesized an epoxy resin containing an amide bond using tyramine and bisphenolic acid as raw materials. Both the tyramine and bisphenolic acid used are biomass raw materials, with outstanding heat resistance, a glass transition temperature (T g ) of 126 °C, high impact strength (21.80 KJ / m 2 without notch) and tensile strength (89.99 MPa), but it cannot be degraded, recycled, or self-healed, nor does it have a dual shape memory function.

[0004] In summary, it is necessary to develop new biomass recyclable shape memory epoxy resins with high heat resistance and high tensile strength. Summary of the Invention

[0005] Aiming at the deficiencies of the prior art, the present invention provides a biomass recyclable shape memory epoxy resin with high heat resistance and high tensile strength and a preparation method thereof. In particular, the epoxy resin of the present invention has self-healing, degradable, and weldable properties.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A preparation method of a bisphenolic acid epoxy monomer, in which a p-hydroxyphenyl alcohol compound and bisphenolic acid are reacted and then epoxidized to obtain the bisphenolic acid epoxy monomer.

[0008] The present invention discloses a biomass recyclable shape memory epoxy resin, and the above bisphenolic acid epoxy monomer is cured to obtain the biomass recyclable shape memory epoxy resin; preferably, the biomass recyclable shape memory epoxy resin is obtained by curing the bisphenolic acid epoxy monomer with a curing agent; more preferably, the biomass recyclable shape memory epoxy resin is obtained by curing the bisphenolic acid epoxy monomer with a biomass curing agent. In the present invention, when curing to prepare the biomass recyclable shape memory epoxy resin, a promoter may or may not be added, and it is preferred to add a promoter, wherein the promoter is preferably a metal compound promoter, and more preferably a metal organic compound promoter, such as an organic zinc compound.

[0009] Preferably, the biomass curing agent is a biomass anhydride; more preferably, the molar ratio of the epoxy group of the bisphenolic acid epoxy monomer to the anhydride group of the biomass anhydride is 1:(0.1 - 1), preferably 1:(0.3 - 0.7), such as 1:0.5.

[0010] Preferably, the dosage of the promoter is 1 - 15% of the mass of the bisphenolic acid epoxy monomer, preferably 5 - 12%, and more preferably 7 - 10%.

[0011] The present invention discloses a shape memory method of the above biomass recyclable shape memory epoxy resin, and the shape memory is shape change and recovery, including the following steps:

[0012] (1) At the deformation temperature, the above biomass recyclable shape memory epoxy resin with the original shape is changed into a new shape; the biomass recyclable shape memory epoxy resin with the new shape is obtained, and the shape change is completed;

[0013] (2) The biomass recyclable shape memory epoxy resin with the new shape is heated to the deformation temperature, and the biomass recyclable shape memory epoxy resin with the new shape is restored to the original shape, and the shape recovery is completed; preferably, it is heated to the deformation temperature and kept warm for 3 - 30 s, preferably, the heat preservation time is 5 - 20 s, and more preferably, the heat preservation time is 10 - 15 s.

[0014] Preferably, the deformation temperature is 10 - 100 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin, and as common knowledge, it is lower than the initial thermal decomposition temperature (5%); preferably, the deformation temperature is 10 - 80 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin, and more preferably, the deformation temperature is 20 - 60 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin.

[0015] The present invention discloses a self - repair method for the above - mentioned biomass - recyclable shape - memory epoxy resin, which includes the following steps: heating the damaged biomass - recyclable shape - memory epoxy resin to complete the self - repair of the biomass - recyclable shape - memory epoxy resin. Preferably, the damage is scratches, cracks, fractures, etc.; the heating temperature is 20 - 80 °C above the glass transition temperature of the biomass - recyclable shape - memory epoxy resin, and preferably the heating temperature is 50 - 80 °C above the glass transition temperature of the biomass - recyclable shape - memory epoxy resin. As an example, the heating is carried out at 180 - 220 °C for 10 minutes to 5 hours, such as at 190 - 210 °C for 20 minutes to 3 hours, and preferably for 0.5 - 2 hours. In the present invention, scratches are made on the surface of the above resin with a blade, and after being placed in an oven at 200 °C, the cracks almost completely disappear. In the present invention, two pieces of the above resin are joined together under the action of an external force, and after being placed in an oven at 200 °C, the welded spline can lift weights more than 200 times its own weight.

[0016] The present invention discloses a degradation method for the above - mentioned biomass - recyclable shape - memory epoxy resin. Mix the above - mentioned biomass - recyclable shape - memory epoxy resin with an alkali solution to achieve its degradation; preferably, the degradation is carried out at room temperature to 100 °C. In the present invention, a small piece of resin is placed in an NaOH solution, and the resin can be completely degraded after 2 hours.

[0017] In the present invention, the chemical structural formula of the p - hydroxybenzyl alcohol compound is as follows:

[0018]

[0019] Among them, n is 0 - 5, preferably 1 - 3, such as tyrosol.

[0020] In the present invention, the molar ratio of the p - hydroxybenzyl alcohol compound to bisphenolic acid is 1∶(0.5 - 1.5), preferably 1∶1; the reaction temperature is 150 - 200 °C, and the time is 1 - 8 h. Preferably, the reaction temperature is 170 - 180 °C, and the time is 4 - 6 h.

[0021] In the present invention, when preparing the bisphenolic acid epoxy monomer, epoxidation is carried out by the reaction of an epoxide compound; the epoxide compound is a compound with a reactive group and an epoxy group, where the reactive group is a group capable of reacting with a hydroxyl group, which can be a halogen, etc.; preferably, the reactive group and the epoxy group are connected by an alkyl chain, and the alkyl chain can be a straight chain or a branched chain; further preferably, the number of carbon atoms in the alkyl chain is 1 - 10, preferably 1 - 5, and further preferably 1 - 3; such as epichlorohydrin, epichlorobutane, etc. The epoxy group is introduced by reacting a halogen with the hydroxyl group on the reaction product of the p - hydroxybenzyl alcohol compound and bisphenolic acid to obtain the bisphenolic acid epoxy monomer.

[0022] Preferably, the molar ratio of the product of the reaction between the p-hydroxyphenyl alcohol compound and bisphenolic acid to the epoxy compound is 1:(5 - 15), preferably 1:10. The temperature of epoxidation is 50 - 100°C, and the time is 0.5 - 5 h.

[0023] In the present invention, the curing temperature is 100 - 200°C, and the time is 5 - 16 h. Preferably, the curing is carried out in a stepwise temperature increase manner, with the holding time at each step temperature being not less than 1 h, and the temperature difference between adjacent steps not exceeding 30°C.

[0024] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0025] 1. Using tyrosol and bisphenolic acid as raw materials, the biomass recyclable shape memory epoxy resin prepared by the present invention has outstanding heat resistance, with a glass transition temperature (T g g) of 140°C. It also has a high flexural modulus (3.86 GPa) and strength (115.1 MPa), and at the same time has a high tensile strength (85.12 MPa), thus providing a reliable basis for its application in cutting-edge fields. In particular, both tyrosol and bisphenolic acid used are biomass raw materials.

[0026] 2. The biomass epoxy thermosetting shape memory resin prepared by the present invention has the advantage of being able to change its initial shape, enabling the reconstruction of its crosslinked network, thereby obtaining a stable permanent shape. The prepared biomass recyclable shape memory epoxy resin has excellent shape recovery performance. At the same time, the epoxy resin of the present invention also has self-healing, degradable, and weldable properties. These application methods overcome the defect that traditional crosslinked polymers cannot be processed again after molding. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is the synthetic reaction formula and chemical structural formula for preparing the intermediate and biomass epoxy monomer in Example 1 of the present invention.

[0028] Figure 2 is the nuclear magnetic resonance hydrogen spectrum ( 1 1H-NMR) of the intermediate in Example 1 of the present invention.

[0029] Figure 3 is the nuclear magnetic resonance carbon spectrum ( 13 13C-NMR) of the intermediate in Example 1 of the present invention.

[0030] Figure 4 is the nuclear magnetic resonance hydrogen spectrum ( 1 1H-NMR) of the biomass epoxy monomer in Example 1 of the present invention.

[0031] Figure 5 is the nuclear magnetic resonance carbon spectrum ( 13 13C-NMR) of the biomass epoxy monomer in Example 1 of the present invention.

[0032] Figure 6 is the high-resolution mass spectrum of the biomass epoxy monomer prepared in Example 1 of the present invention;

[0033] Figure 7 is the thermogravimetric (TGA) curve of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention, 10 °C / min, nitrogen.

[0034] Figure 8 is the dynamic thermomechanical analysis (DMA) curve of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention, 3 °C / min.

[0035] Figure 9 is the tensile stress-strain curve of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention.

[0036] Figure 10 is the shape memory electron image of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention.

[0037] Figure 11 is the self-healing electron image of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention.

[0038] Figure 12 is the welding electron image of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention.

[0039] Figure 13 is the degradation electron image of the biomass recyclable shape memory epoxy resin prepared in Example 1 of the present invention. Detailed implementation manners

[0040] The technical solution of the present invention will be further described below in conjunction with the accompanying drawings and embodiments; all raw materials are commercially available, and the specific preparation operations and testing methods involved are conventional methods in the art. The mechanical properties are tested using a universal testing machine (MTS CMT-4104, China), and the testing standards for tensile tests refer to the American Materials Testing Standard ASTM-D882, and the testing standards for bending tests refer to the Chinese Materials Testing Standard GBT2570-1995. The molecular weight of the epoxy monomer is tested using high-resolution mass spectrometry (HRMS, MICRO TOF-QIII, Germany, ESI+). 1H-NMR and 13C–NMR spectra are tested using a nuclear magnetic resonance spectrometer (Bruker 400-600mhz, Germany), and the solvent is CDCl3 or DMSO-d6. The thermal stability of the resin in a N2 atmosphere is studied using a thermogravimetric analyzer (TGA, Discovery, USA), and the sample is heated from room temperature to 800°C at a heating rate of 10°C / min. The morphology before and after microcrack self-repair is observed using a super-depth-of-field microscope (VH X 5000, Japan). The dynamic thermomechanical properties of the material are tested using a dynamic thermomechanical analyzer (DMA, TA Q800, USA), with a frequency of 1 Hz, heating from 25°C to 250°C at a heating rate of 3°C / min, and the specimen size is 30 mm × 3 mm × 1 mm.

[0041] As an example, the preparation process of the biomass recyclable shape memory epoxy resin disclosed in the present invention is shown in Figure 1 , and is specifically as follows:

[0042] (1) After reacting tyrosol and bisphenolic acid by heating, an intermediate is obtained;

[0043] (2) Reacting the intermediate and epichlorohydrin by heating to obtain a bisphenolic acid epoxy monomer;

[0044] (3) Curing the bisphenolic acid epoxy monomer to obtain a biomass recyclable shape memory epoxy resin.

[0045] In the above step (1), the molar ratio of tyrosol to bisphenolic acid is 1:(0.5 - 1.5), preferably 1:1; the temperature for the heating reaction is 170 - 185°C, and the time is 3 - 8 h. Preferably, the temperature for the heating reaction is 175 - 180°C, and the time is 4 - 6 h; in step (2), the molar ratio of the intermediate to epichlorohydrin is 1:(5 - 15), preferably 1:10; the heating reaction is carried out in an alcohol solvent. Preferably, the alcohol solvent is ethanol; the temperature for the heating reaction is 80 - 100°C, and the time is 1 - 2 h. Preferably, the temperature for the heating reaction is 80 - 90°C, and the time is 1.5 - 2 h; the heating reaction is carried out in the presence of an inorganic base. Preferably, the inorganic base is sodium hydroxide, potassium hydroxide, etc.; the amount of the inorganic base is 1 - 1.5 times the molar amount of phenolic hydroxyl groups in the intermediate, preferably 1.1 - 1.2 times, such as 1.1 times; in step (3), the curing temperature is 100 - 160°C, and the time is 5 - 16 h. Preferably, the curing is carried out in a stepwise temperature increase manner, and the heat preservation time at each step temperature is not less than 1 h, and the temperature difference between adjacent steps does not exceed 30°C.

[0046] Specifically, the preparation method of the biomass recyclable shape memory epoxy resin of the present invention is as follows:

[0047] (1) By mole, 100 parts of tyrosol and 100 parts of bisphenolic acid are mixed, and then stirred and reacted at 175 - 180°C for 4 - 6 h, and naturally cooled to room temperature to obtain an intermediate;

[0048] (2) By mole, 100 parts of the intermediate and 1000 parts of epichlorohydrin are mixed in ethanol, and then an aqueous sodium hydroxide solution (1 mol / L, 1 - 1.5 times the equivalent amount per mole of phenolic hydroxyl group) is added dropwise to the mixture, and the reaction is carried out at 80 - 100°C for 1 - 2 h, and naturally cooled to room temperature. Then the mixture is mixed with dichloromethane, washed with deionized water, and rotary evaporated (80°C, 0.1 MPa) to remove the solvent, and a bisphenolic acid epoxy monomer is obtained by vacuum distillation (120°C);

[0049] (3) The bisphenolic acid epoxy monomer obtained in step (2) is defoamed and then cured to obtain a biomass recyclable shape memory epoxy resin.

[0050] The present invention discloses a method for shape change and recovery of the above biomass recyclable shape memory epoxy resin, including the following steps:

[0051] (1) At the deformation temperature, the biomass recyclable shape memory epoxy resin with the original shape is changed into a new shape to obtain a biomass recyclable shape memory epoxy resin with the new shape, and the shape change is completed; as common knowledge, the deformation is achieved under the action of conventional external forces;

[0052] (2) Heat the biomass recyclable shape memory epoxy resin with the new shape to the deformation temperature and keep it warm for 5 - 20 s. The biomass recyclable shape memory epoxy resin with the new shape returns to its original shape, completing the shape recovery.

[0053] In the above technical solution, the deformation temperature is 10 - 100 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin. As common knowledge, it is lower than the initial thermal decomposition temperature (5%); preferably, the deformation temperature is 10 - 80 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin. More preferably, the deformation temperature is 20 - 60 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin.

[0054] Preferably, when the deformation temperature in step (1) is 10 - 40 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin, step (2) is carried out without external force, and the biomass recyclable shape memory epoxy resin with the new shape can be restored to its original shape, indicating that the product of the present invention has excellent shape memory ability. Further, step (2) can also be carried out under external force.

[0055] Preferably, when the deformation temperature in step (1) is 40 - 100 °C above the glass transition temperature of the biomass recyclable shape memory epoxy resin, step (2) is carried out under external force, and the biomass recyclable shape memory epoxy resin with the new shape can be restored to its original shape. In particular, the biomass recyclable shape memory epoxy resin with the new shape obtained in step (1) of this method has good shape retention ability. Without external force, when heated to the deformation temperature, it cannot be restored to the original shape, which is very beneficial for the application of structural materials; further, when the original shape is required, apply an external force (the force that can achieve the original shape), and heat it to the deformation temperature to restore it to the original shape, indicating that the product of the present invention has excellent shape memory ability.

[0056] The specific example steps of the method for shape change and recovery of the above biomass recyclable shape memory epoxy resin are as follows:

[0057] (1) When the temperature is heated to 10 - 20 °C above the glass transition temperature, under external force, change the resin with the original shape into the required new shape.

[0058] (2) Cool to room temperature, and the new shape described in step (1) is fixed, becoming a new permanent shape II of the biomass recyclable shape memory epoxy resin.

[0059] (3) Heat the biomass recyclable shape memory epoxy resin with the new permanent shape II to 10 - 20 °C above its glass transition temperature and hold for 5 - 20 s. The resin will automatically return from the permanent shape II in step (2) to the permanent original shape I, i.e., the original shape. When heating, the resin is conventionally placed in an oven without external force.

[0060] Example 1

[0061] (1) Preparation of intermediate

[0062] Mix 6 g of tyrosol (CAS#: 501 - 94 - 0) and 12.52 g of bisphenolic acid (CAS#: 126 - 00 - 1), then stir and react at 175 °C for 4 h, then naturally cool to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate with a yield of 92%; its nuclear magnetic resonance hydrogen spectrum ( 1 H-NMR) and nuclear magnetic resonance carbon spectrum ( 13 C-NMR) are shown in Appendix Figure 2 and Figure 3 .

[0063] (2) Preparation of bisphenolic acid epoxy monomer

[0064] At room temperature, mix 10 g of the intermediate and 16.10 g of epichlorohydrin in 35 mL of ethanol, then add sodium hydroxide aqueous solution (1 mol / L, 1.1 times the equivalent amount per mole of phenolic hydroxyl group) dropwise to the mixture. After the addition is completed (1 minute), react at 80 °C for 2 h, then naturally cool to room temperature. Mix the obtained mixture with 30 mL of dichloromethane, wash with 100 mL of deionized water, then remove dichloromethane and most of the ethanol by rotary evaporation (80 °C, 0.1 MPa), and then obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C) with a yield of 93%; Figure 4 is its nuclear magnetic resonance hydrogen spectrum ( 1 H NMR); Figure 5 is its nuclear magnetic resonance carbon spectrum ( 13 C-NMR); Figure 6 is its high-resolution mass spectrum.

[0065] (3) Preparation of biomass recyclable shape memory epoxy resin

[0066] Mix 10.0 g of bisphenol acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, pour it into a mold conventionally, and then defoam it (80 °C, 10 min, 0.1 MPa). Then, cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h. After curing, let it cool naturally in the oven to obtain the biomass recyclable shape memory epoxy resin. The thermogravimetric curve, dynamic thermomechanical analysis (DMA) curve and tensile stress-strain curve are respectively shown in Figure 7 , Figure 8 , Figure 9 .

[0067] It can be seen from this that the glass transition temperature (T g DMA) of the above biomass recyclable shape memory epoxy resin is 140 °C, and T d5% is 293 °C. Further, the flexural modulus, flexural strength and tensile strength of the above biomass recyclable shape memory epoxy resin at room temperature are 3.86 GPa, 115.1 MPa and 85.12 MPa respectively, showing outstanding mechanical properties.

[0068] See Figure 10 , the specific steps of the shape change and recovery method of the above biomass recyclable shape memory epoxy resin are as follows:

[0069] (1) At 160 °C, under the action of an external force, change the resin with the original shape into the required new shape;

[0070] (2) Naturally cool to room temperature, and the new shape described in step (1) is fixed to become a new permanent shape II of the biomass recyclable shape memory epoxy resin;

[0071] (3) Place the biomass recyclable shape memory epoxy resin with the new permanent shape II at 160 °C (without external force) for 10 seconds, and the resin automatically returns from the permanent shape II in step (2) to the permanent original shape I, that is, the original shape.

[0072] Further:

[0073] (4) At 200 °C, under the action of an external force, change the resin with the original shape into the required new shape, and maintain this temperature and external force for 30 min; to become a new permanent shape III of the biomass recyclable shape memory epoxy resin;

[0074] (5) At 160 °C, under the action of an external force, change the resin with the permanent shape III into the required new shape;

[0075] (6) Naturally cool to room temperature, and the new shape described in step (5) is fixed to become a new permanent shape Ⅳ of the biomass recyclable shape memory epoxy resin;

[0076] (7) Place the biomass recyclable shape memory epoxy resin with the new permanent shape Ⅳ at 160 °C (without external force) for 8 seconds, and the resin automatically returns from the permanent shape Ⅳ in step (6) to the permanent shape Ⅲ, not the original shape;

[0077] (8) At 200 °C, under the action of external force for 30 min, restore the resin with the permanent shape Ⅲ to the original shape.

[0078] In this embodiment, a conventional mold is used to provide external force. In actual production or application, other methods that can deform the resin strip can also be used, which is a conventional technique.

[0079] The microcrack self-healing performance test of the above-mentioned biomass recyclable shape memory epoxy resin is as Figure 11 shown. Use a blade to scratch a 118-μm-wide scratch on the resin surface, and then place it in an oven at 200 °C for 30 min. The crack almost completely disappears and cannot be observed.

[0080] The welding performance test of the above-mentioned biomass recyclable shape memory epoxy resin is as Figure 12 shown. Fit two resin strips (with dimensions of 40 mm × 10 mm × 1 mm) under the action of external force. After placing them in an oven at 200 °C for 2 h, the welded sample strip can lift a weight (500 g) more than 200 times its own weight. Under the same experiment, the biomass self-curing epoxy resin prepared by CN2023101626543 did not achieve welding after 2 h.

[0081] In this embodiment, an experimental clamp is used to provide external force. In actual production or application, other methods that can make two resin strips fit can also be used, which is a conventional technique.

[0082] The degradability test of the above-mentioned biomass recyclable shape memory epoxy resin is as Figure 13 shown. Place a small piece of resin (weight 0.1 g) in a 1 mol / L NaOH aqueous solution at 90 °C, and the resin can be completely degraded after 2 h. Under the same experiment, the biomass self-curing epoxy resin prepared by CN2023101626543 did not degrade after 2 h.

[0083]

[0084] As can be seen from Table 1, the biomass recyclable shape memory epoxy resin prepared by the present invention has excellent heat resistance and very good mechanical properties.

[0085] Example Two

[0086] (1) Preparation of intermediate

[0087] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 175 °C for 5 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0088] (2) Preparation of bisphenolic acid epoxy monomer

[0089] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, add an aqueous sodium hydroxide solution (1 mol / L, 1.1 times the equivalent amount per mole of phenolic hydroxyl group) dropwise to the mixture. After the addition is completed (1 minute), react at 80 °C for 2 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0090] (3) Preparation of biomass recyclable shape memory epoxy resin

[0091] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa), and then place the mold in a forced-air drying oven, and cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h; after the curing is completed, cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0092] Example 3

[0093] (1) Preparation of intermediate

[0094] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 175 °C for 5 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0095] (2) Preparation of bisphenolic acid epoxy monomer

[0096] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol. Dropwise add an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 90 °C for 2 h, and naturally cool to room temperature. Mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol. Obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0097] (3)Preparation of biomass recyclable shape memory epoxy resin

[0098] Mix 10.0 g of the bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride, and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, and place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa). Then place the mold in a forced-air drying oven and cure it according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h in sequence; after the curing is completed, let it cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0099] Example 4

[0100] (1)Preparation of the intermediate

[0101] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 175 °C for 5 h, naturally cool to room temperature, wash with boiling water, and then rotary evaporate (70 °C, 0.1 MPa) to remove water to obtain the intermediate.

[0102] (2)Preparation of the bisphenolic acid epoxy monomer

[0103] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol. Dropwise add an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 100 °C for 1 h, naturally cool to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol. Obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0104] (3)Preparation of biomass recyclable shape memory epoxy resin

[0105] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa), and then put the mold into a forced-air drying oven and cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h; after the curing is completed, let it cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0106] Example 5

[0107] (1) Preparation of intermediate

[0108] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 175 °C for 6 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0109] (2) Preparation of bisphenolic acid epoxy monomer

[0110] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, dropwise add an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture, and react at 80 °C for 2 h after the addition is completed (1 minute). Cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0111] (3) Preparation of biomass recyclable shape memory epoxy resin

[0112] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa), and then put the mold into a forced-air drying oven and cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h; after the curing is completed, let it cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0113] Example 6

[0114] (1) Preparation of intermediate

[0115] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 175 °C for 4 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0116] (2) Preparation of bisphenolic acid epoxy monomer

[0117] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, add dropwise an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 100 °C for 2 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0118] (3) Preparation of biomass recyclable shape memory epoxy resin

[0119] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa), and then place the mold in a forced-air drying oven, and cure according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h in sequence; after the curing is completed, cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0120] Example 7

[0121] (1) Preparation of the intermediate

[0122] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 180 °C for 4 h, cool naturally to room temperature, wash with boiling water, and then rotary evaporate (70 °C, 0.1 MPa) to remove water to obtain the intermediate.

[0123] (2) Preparation of bisphenolic acid epoxy monomer

[0124] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, add dropwise an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 80 °C for 2 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0125] (3) Preparation of biomass recyclable shape memory epoxy resin

[0126] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for degassing (80 °C, 10 min, 0.1 MPa), and then put the mold into a forced-air drying oven and cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h; after the curing is completed, let it cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0127] Example 8

[0128] (1) Preparation of intermediate

[0129] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 180 °C for 5 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0130] (2) Preparation of bisphenolic acid epoxy monomer

[0131] Mix 10 g of the intermediate and 15 g of epichlorohydrin in ethanol, dropwise add an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 80 °C for 2 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0132] (3) Preparation of biomass recyclable shape memory epoxy resin

[0133] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for degassing (80 °C, 10 min, 0.1 MPa), and then put the mold into a forced-air drying oven and cure it successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h; after the curing is completed, let it cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0134] Example 9

[0135] (1) Preparation of intermediate

[0136] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 180 °C for 5 h, cool naturally to room temperature, wash with boiling water, and then remove water by rotary evaporation (70 °C, 0.1 MPa) to obtain the intermediate.

[0137] (2) Preparation of bisphenolic acid epoxy monomer

[0138] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, add dropwise an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 100 °C for 1 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0139] (3) Preparation of biomass recyclable shape memory epoxy resin

[0140] Mix 10.0 g of bisphenolic acid epoxy monomer, 2.5 g of itaconic anhydride and 0.91 g of zinc acetylacetonate evenly at 80 °C, put them into a mold, place the mold in a vacuum oven for defoaming (80 °C, 10 min, 0.1 MPa), and then place the mold in a forced-air drying oven, and cure according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h in sequence; after the curing is completed, cool naturally with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0141] Example 10

[0142] (1) Preparation of the intermediate

[0143] Mix 6 g of tyrosol and 12.52 g of bisphenolic acid, stir and react at 180 °C for 6 h, cool naturally to room temperature, wash with boiling water, and then rotary evaporate (70 °C, 0.1 MPa) to remove water to obtain the intermediate.

[0144] (2) Preparation of bisphenolic acid epoxy monomer

[0145] Mix 10 g of the intermediate and 16.10 g of epichlorohydrin in ethanol, add dropwise an aqueous sodium hydroxide solution (1 mol / L, 1.1-fold equivalent per mole of phenolic hydroxyl group) to the mixture. After the addition is completed (1 minute), react at 80 °C for 2 h, cool naturally to room temperature, mix the mixture with dichloromethane, wash with deionized water, and rotary evaporate (80 °C, 0.1 MPa) to remove dichloromethane and most of the ethanol, and obtain the bisphenolic acid epoxy monomer by vacuum distillation (120 °C).

[0146] (3) Preparation of biomass recyclable shape memory epoxy resin

[0147] 10.0 g of bisphenolic acid epoxy monomer, 2.9 g of itaconic anhydride and 0.85 g of zinc acetylacetonate were mixed evenly at 80 °C, put into a mold, and the mold was placed in a vacuum oven for degassing (80 °C, 10 min, 0.1 MPa). Then the mold was placed in a forced-air drying oven and cured successively according to the process of 100 °C / 2 h + 120 °C / 2 h + 140 °C / 2 h + 160 °C / 2 h. After curing, it was naturally cooled with the oven to obtain the biomass recyclable shape memory epoxy resin.

[0148] In this invention, tyrosol and bisphenolic acid were used as raw materials to synthesize an epoxy resin containing ester bonds. Both tyrosol and bisphenolic acid used are biomass raw materials. The prepared biomass recyclable shape memory epoxy resin has outstanding heat resistance, and its glass transition temperature (T g g) is 140 °C. It also has a high flexural modulus (3.86 GPa) and strength (115.1 MPa). At the same time, it also has a high tensile strength (85.12 MPa). Compared with the prior art, this invention realizes the preparation of biomass epoxy resin from all biomass raw materials, and this resin has very excellent comprehensive properties, thus providing a reliable basis for its application in cutting-edge fields.

Claims

1. A preparation method of bisphenolic acid epoxy monomer, characterized in that, The p - hydroxybenzyl alcohol compound and bisphenolic acid are reacted and then epoxidized to obtain a bisphenolic acid epoxy monomer; the epoxidation is carried out by reacting with an epoxy compound, and the molar ratio of the product of the reaction of the p - hydroxybenzyl alcohol compound and bisphenolic acid to the epoxy compound is 1∶(5 - 15); the molar ratio of the p - hydroxybenzyl alcohol compound to bisphenolic acid is 1∶(0.5 - 1.5); the chemical structural formula of the p - hydroxybenzyl alcohol compound is as follows: ； Wherein, n is 0 - 5.

2. A preparation method of a biomass recyclable shape memory epoxy resin, characterized in that, The bisphenolic acid epoxy monomer is prepared by using the preparation method of the bisphenolic acid epoxy monomer described in claim 1; the bisphenolic acid epoxy monomer and a curing agent are cured to obtain a biomass - recyclable shape - memory epoxy resin; the curing agent is itaconic anhydride.

3. The bisphenolic acid epoxy monomer or the biomass - recyclable shape - memory epoxy resin prepared by the method according to claim 1 or 2.

4. The shape memory method of the biomass recyclable shape memory epoxy resin according to claim 3, characterized in that, Comprising the following steps: (1) At the deformation temperature, the biomass - recyclable shape - memory epoxy resin with the original shape is changed into a new shape; the biomass - recyclable shape - memory epoxy resin with the new shape is obtained, and the shape change is completed. (2) The biomass - recyclable shape - memory epoxy resin with the new shape is heated to the deformation temperature, and the biomass - recyclable shape - memory epoxy resin with the new shape is restored to the original shape, and the shape restoration is completed.

5. The shape memory method of the biomass recyclable shape memory epoxy resin according to claim 4, characterized in that, The deformation temperature is 10 - 100 °C above the glass transition temperature of the biomass - recyclable shape - memory epoxy resin.

6. The self-healing method of the biomass recyclable shape memory epoxy resin according to claim 3, comprising the following steps: The damaged biomass - recyclable shape - memory epoxy resin is heated to complete the self - repair of the biomass - recyclable shape - memory epoxy resin.

7. The degradation method of the biomass - recyclable shape - memory epoxy resin according to claim 3, wherein the biomass - recyclable shape - memory epoxy resin is mixed with an alkali solution to achieve its degradation.

8. The application of the bisphenolic acid epoxy monomer or the biomass - recyclable shape - memory epoxy resin according to claim 3 in the preparation or as an epoxy resin material.

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