CN113831706B

CN113831706B - High-toughness polycaprolactone remodelable shape memory material and preparation method thereof

Info

Publication number: CN113831706B
Application number: CN202110954669.4A
Authority: CN
Inventors: 马文中; 张佑; 杨海存; 钟璟
Original assignee: Changzhou University
Current assignee: Changzhou University
Priority date: 2021-08-19
Filing date: 2021-08-19
Publication date: 2022-05-31
Anticipated expiration: 2041-08-19
Also published as: CN113831706A

Abstract

The invention belongs to the field of shape memory materials, and particularly relates to a high-toughness polycaprolactone remodelable shape memory material and a preparation method thereof. The invention proves that the method of ultrasonic treatment can reconstruct the butyl-endocyclic ring generated by photodimerization into conjugated double bonds. The mechanochemical means has mild conditions, can accurately regulate and control the molecular structure of the polymer, and is safer and more environment-friendly. The selected crosslinking node is the slidable polyrotaxane, so that the defect of uneven distribution of internal stress of the material in stress circulation can be effectively overcome, and the material has the characteristics of high toughness and high shape recovery rate.

Description

High-toughness polycaprolactone remodelable shape memory material and preparation method thereof

Technical Field

The invention belongs to the field of shape memory materials, and particularly relates to a high-toughness polycaprolactone remodelable shape memory material and a preparation method thereof.

Background

Mechanochemical in the chemical reaction level mainly means that mechanical energy is applied to condensed substances such as solids, liquids and the like by means of shearing, friction, impact, extrusion and the like, so that the structures and physicochemical properties of the substances are induced to change, and a chemical reaction is induced. Unlike ordinary thermochemical reaction, the mechanochemical reaction is powered by mechanical energy rather than thermal energy, so that the reaction can be completed without harsh conditions such as high temperature, high pressure and the like. In recent years, the use of mechanochemistry to direct structural transformations of polymers has produced a series of engineered molecular responses spanning optical, mechanical, electronic and thermal properties, with a wide range of applications in material science, polymer physics, mechanics and additive manufacturing. Polymer mechanochemistry has evolved into a highly accurate tool for inducing molecular reorganization in response to macroscopic effects, a new opportunity to innovate response material design methods.

Although the molecular structure of the polymer can be accurately regulated and controlled through the conventional thermochemical reaction, the separation and purification of products are involved, the synthesis steps are complicated, a large amount of solvents are needed, and the requirements of high efficiency and environmental protection are difficult to achieve. In order to prevent the memory performance reduction caused by the slippage of polymer molecular chains in the shape memory cycle, the polymer molecular chains need to be crosslinked to fix the permanent shape, but the conventional covalent crosslinking mode is difficult to prepare a crosslinked structure with uniform network, so that the stress distribution is uneven, and the secondary processing cannot be carried out.

Disclosure of Invention

Aiming at the problems, the invention provides a high-toughness polycaprolactone remodelable shape memory material and a preparation method thereof.

The technical purpose is achieved, the technical effect is achieved, and the invention is realized through the following technical scheme:

a preparation method of a high-toughness polycaprolactone remodelable shape memory material comprises the following steps:

s1: initiating epsilon-caprolactone to open a ring to prepare linear Polycaprolactone (PCL) by using ethylene glycol as an initiator and stannous octoate as a catalyst;

s2: synthesizing 4- ((4-methyl-2-oxo-2H-chromium-7-yl) oxy) butyric acid (COU-COOH), and modifying a terminal hydroxyl group of the PCL into a coumarin group by adopting a Steglich esterification reaction;

s3: uniformly mixing the modified PCL in S2 with benzophenone, pressing into a sheet shape, irradiating under ultraviolet light to perform chain extension reaction, preparing the PCL subjected to chain extension by illumination into a solution, and performing ultrasonic treatment to prepare the PCL (also called PCL cross-linked network precursor) with a conjugated double bond on a main chain;

s4: alpha-cyclodextrin (alpha-CD) is selected as a main body, and polyethylene glycol diamine (PEG-NH)₂) Preparing Polyrotaxane (PR) for an object, and modifying a molecular ring on the polyrotaxane to prepare a polyrotaxane crosslinking agent containing double bonds;

s5: and uniformly mixing the PCL with the conjugated double bond on the main chain prepared in the S3 and the polyrotaxane crosslinking agent prepared in the S4, and carrying out Diels-Alder reaction at the reaction temperature to crosslink (the reaction temperature is preferably 70 ℃), so as to prepare the high-toughness polycaprolactone remodelable shape memory material.

Further, in S5, the molar ratio of the number of conjugated double bonds on PCL to the double bonds on polyrotaxane in the polymer crosslinking system is: 1:1, which can ensure the complete progress of the thermal crosslinking reaction.

Furthermore, in S4, the molecular weights of the polyethylene glycol diamine are respectively 10kDa to 35kDa, and a large steric hindrance end-capping reagent N-benzyloxycarbonyl-L-tyrosine is selected in the preparation of the polyrotaxane.

Further, in S4, the double bond-containing polyrotaxane crosslinking agent is prepared by the following method: the alpha-CD group on PR is first hydroxypropyl activated with propylene oxide and then double bond is grafted with 2-ethyl propenyl ethyl isocyanate.

Further, in S3, the molar ratio of the amount of the benzophenone to the modified coumarin group at the end of the PCL is 1: 1-1: 2, and the ratio ensures sufficient ultraviolet light absorption intensity.

Furthermore, the concentration of the PCL solution prepared in S3 after chain extension by illumination is 0.1-1 mg/mL.

Further, in S2, a method for synthesizing 4- ((4-methyl-2-oxo-2H-chromen-7-yl) oxy) butyric acid comprises: 4-methyl umbelliferone is selected as a raw material, is substituted by 4-ethyl bromobutyrate, and is hydrolyzed under alkaline conditions to prepare carboxylated coumarin, namely 4- ((4-methyl-2-oxo-2H-chromium-7-yl) oxy) butyric acid.

Further, in S1, in the ring-opening polymerization of e-caprolactone, the molar ratio of ethylene glycol to e-caprolactone is 1: 50-1: 100.

The invention also provides a high-toughness polycaprolactone remodelable shape memory material prepared based on the preparation method.

The invention has the beneficial effects that:

(1) the PCL cross-linked network precursor with controllable conjugated double bond positions on a molecular chain is synthesized by ultraviolet light, ultrasonic treatment and other treatment methods, and the ultrasonic treatment method proves that the butyl inner ring generated by photodimerization can be reconstructed into conjugated double bonds. Compared with the traditional thermochemical reaction, the method can also accurately regulate and control the molecular structure of the polymer, and is safer and more environment-friendly;

(2) the selected crosslinking mode is thermo-reversible DA reaction, the material can be shaped at 70 ℃, and network crosslinking is performed at 140 ℃, so that the material has thermo-plasticity;

(3) the selected crosslinking node is the slidable polyrotaxane, so that the defect of uneven distribution of internal stress of the material in stress circulation can be effectively overcome, and the material has the characteristics of high toughness and high shape recovery rate.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

FIG. 1 is a graph comparing the nuclear magnetic hydrogen spectrum and the carbon spectrum of 4-Me-7-OH-COU and COU-COOH prepared in example 1;

FIG. 2 shows pure PCL and PCL-COU prepared in example 1¹H NMR nuclear magnetic spectrum;

FIG. 3 is a comparison graph of gel permeation chromatography of pure PCL, PCL-COU and sonicated PCL-COU-BP prepared in example 3;

FIG. 4 is a drawing showing the preparation of polyrotaxane prepared in examples 1, 2 and 3¹H NMR Nuclear magnetic Spectrum

FIG. 5 is the PCL reaction equation of PCL-COU under UV and ultrasonic treatment to prepare PCL with definite conjugate double bond position.

Detailed Description

The present invention is not limited to the following embodiments, and those skilled in the art can implement the present invention in other embodiments according to the disclosure of the present invention, or make simple changes or modifications on the design structure and idea of the present invention, and fall into the protection scope of the present invention. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The invention is described in more detail below with reference to the following examples:

the reagents used in the invention are all purchased from the market, and the detection instrument comprises:

infrared spectroscopy (FTIR): infrared tests and analyses were performed using a Fourier transform Infrared spectrometer (model Avatar 370) (Thermomani high force instruments, USA) using the prepared samples, FTIR passes were recorded at 4000 and 500cm^-1Obtained by scanning 32 times in between and has resolution of 2cm^-1。

Nuclear magnetic resonance spectrum (¹H-NMR): the nuclear magnetic resonance spectrometer is Bruker ARX-500 product of Bruker company of Switzerland, and the resolution ratio<0.2 Hz; sensitivity of the probe>100. The experiment adopts nuclear magnetic resonance hydrogen spectrum analysis, takes deuterated chloroform and deuterated dimethyl sulfoxide as solvents, has the working frequency of 500MHz and the magnetic field intensity of 7.05T, and is tested at normal temperature.

Gel Permeation Chromatography (GPC): the molecular weight of the polymer was determined by gel permeation chromatography model Waters515 from Wyatt, USA, using a high pressure liquid chromatography pump model Water515, a detector model 2414RI, a Shodex KD-806M column (pore size 104105,106 nm), THF as the mobile phase, a flow rate of 1mL/min, a test temperature of 35 ℃ and a calibration with monodisperse polystyrene standards.

Secondly, the method for preparing the polycaprolactone remodelable shape memory material with high toughness comprises the following steps:

s4: preparing Polyrotaxane (PR) by using alpha-cyclodextrin (alpha-CD) as a main body and polyethylene glycol diamine (PEG-NH2) as an object, and modifying molecular rings on the polyrotaxane to prepare a polyrotaxane crosslinking agent containing double bonds;

s5: and uniformly mixing the PCL with the conjugated double bond on the main chain prepared in the S3 and the poly rotaxane crosslinking agent prepared in the S4, and performing Diels-Alder reaction at the reaction temperature to crosslink the PCL and the poly rotaxane crosslinking agent to prepare the high-toughness polycaprolactone remodelable shape memory material.

The method comprises the following specific steps:

s1 Ring opening polymerization under nitrogen atmosphere using catalyst stannous Isooctoate (Sn (Oct)₂) The process is carried out. The required amount of the initiator ethylene glycol and the monomer epsilon-caprolactone is calculated according to the molar ratio of 1: 50-1: 100, and the catalyst Sn (Oct)₂The content of (B) is 1 wt%. And (3) placing the reaction bottle in an oil bath kettle which is preheated to 140 ℃ in advance, stirring, and ending the reaction until the rotation of the magnetic stirrer is stopped. And precipitating with n-hexane to recover the polymer, and drying in a vacuum drying oven at 40 ℃ for 24h to obtain hydroxyl-terminated PCL-OH.

S2, mixing 4-methylumbelliferone (COU-OH, 5g, 28.4mmol) and potassium carbonate (K)₂CO₃5.9g, 42.7mmol) and potassium iodide (KI, 0.2g, 1.2mmol) with 100mL of anhydrous acetone in a 250mL three-necked round-bottomed flask under nitrogen atmosphere with vigorous stirring, followed by dropwise addition of ethyl 4-bromobutyrate (5.1mL, 35.5mmol) to the suspension, refluxing of the reaction mixture at 58 ℃ for 20h, after completion of the reaction the cooled reaction mixture was concentrated by filtration under reduced pressure and then dried in a vacuum oven at 40 ℃ for 24 h. And after drying, recrystallizing twice by using ethanol to obtain an intermediate 4-Me-7-OH-COU.

The resulting 4-Me-7-OH-COU (3g, 10.3mmol) was dissolved in 58mL of isopropanol solution, 40mL of aqueous NaOH (4.1g, 103mmol) was added and the mixture was stirred at 90 ℃ for 12 h. After cooling to room temperature, the solution was transferred to an ice water bath and then acidified with concentrated HCl to adjust the pH to about 2. Recrystallizing the precipitate with ethanol twice, and drying in a vacuum oven at 30 deg.C for 24 hr to obtain carboxylated coumarin (COU-COOH).

Under a nitrogen atmosphere, a designed amount of PCL-OH (1.71g, 4X 10)^-4mol)、DCC(0.206g，1×10^-3mol) and DMAP (3 wt%) were dissolved in anhydrous DCM and stirred well. Thereafter, COU-COOH (0.262g, 1X 10)^-3mol) of anhydrous N, N-dimethyl formamideThe amide solution (DMF) was added dropwise to the reaction solution and stirred until it was completely dissolved, and the reaction was carried out at 30 ℃ for 48 hours with stirring. And finally, removing insoluble byproducts through suction filtration, settling in anhydrous ether, centrifugally collecting, washing with the anhydrous ether for 1-2 times, and drying in a vacuum drying oven at 30 ℃ for 24 hours to obtain the linear polycaprolactone (PCL-COU) with the tail end of coumarin.

S3, dissolving the PCL-COU and the benzophenone in 10ml of dichloromethane (the molar ratio of the amount of the benzophenone to the coumarin group on the PCL-COU is 1:1), removing the solvent by rotary evaporation, drying for 24h in a vacuum drying oven at 50 ℃, putting the dried sample into a special film, and pressing and processing the sample into a sheet shape by a flat vulcanizing machine at 80 ℃. And fixing the plate between quartz plates, heating the plate on a heating plate at 60 ℃, illuminating the plate in a 365nm ultraviolet box for 6 hours, weighing a certain amount of sample after the illumination is finished, dissolving the sample in 100mL dichloromethane, and preparing a 0.1-1 mg/mL diluted solution. And (3) carrying out ultrasonic treatment on the diluted solution in an ultrasonic instrument for 30min to ensure that PCL molecules are reconstructed into a conjugated double bond structure under the action of mechanical force, thus obtaining the PCL crosslinking network precursor containing conjugated double bonds on the main chain.

S4, mixing PEG-NH with different molecular weights₂(2.3×10^-5mol) was added to a saturated solution of α -CD (7.25g/50mL of ultrapure water), and the solution was stirred at room temperature for 24 hours to give a white gelatinous solid. And then, the sample is placed in a low-temperature refrigerator for 12 hours to be completely frozen and is freeze-dried in a freeze dryer to obtain the clathrate compound. Then 0.82g of N-benzyloxycarbonyl-L-tyrosine (2.6X 10) was added in this order to a previously dried vacuum reaction flask^-3mol), 1.15g of Kate condensate BOP (2.6X 10)^-3mol)，0.35g HOBt(2.6×10^-3mol), 0.45mLN, N-diisopropylethylamine DIEA (2.6X 10)^-3mol) and dissolved in 15mL of anhydrous DMF, after which the lyophilized inclusion compound is added to the solution and the suspension is stirred at room temperature for 24 h. The suspension was precipitated in excess ether to give the crude product, and the precipitate was collected by centrifugation at 7000 rpm for 5 minutes at room temperature. Finally, continuously stirring in a large amount of acetone, methanol and water for 3h respectively, centrifugally collecting precipitates, and drying in vacuum at 50 ℃ for 48h to obtain Polyrotaxane (PR), wherein the polyrotaxane prepared in example 1 is marked as PR (10), and the polyrotaxane prepared in example 2 is marked as PR (10)Rotaxane is represented by PR (20), and polyrotaxane prepared in example 3 is represented by PR (35), namely PR prepared in example 1 has a molecular weight of 10kDa, PR prepared in example 2 has a molecular weight of 20kDa, and PR prepared in example 3 has a molecular weight of 35 kDa.

Polyrotaxane (500mg) was dissolved in 50mL of 1mol/L sodium hydroxide solution, 4.6mL of propylene oxide (66mmol) was added dropwise to the solution under ice bath conditions, and the mixture was stirred overnight. The reaction temperature was gradually raised to room temperature as the ice in the solution melted. After hydroxypropylation, the sample was purified by dialysis against deionized water. To remove free PEG produced by the decomposition during hydroxypropylation, the lyophilized sample was poured into 100mL CH₂Cl₂Stirring overnight to filter out PEG, then adding acetone (100mL), stirring for 3h, centrifuging at 7000 rpm for 5min to collect precipitate, and vacuum drying the precipitate at 50 ℃ for 48h to obtain hydroxypropylated polyrotaxane.

Hydroxypropylated polyrotaxane (500mg), DBTDL (1 drop) and BHT (0.78mg) were dissolved in 30ml of anhydrous DMSO. 2-Acryloxyethyl isocyanate (78mg) was dissolved in 10ml of anhydrous dimethyl sulfoxide, and the solution was dropped into the mixture in the absence of light and stirred vigorously. The mixture was then stirred continuously overnight at 40 ℃ to ensure completion of the reaction. Reprecipitation from the reaction mixture was carried out with excess methanol or acetone, respectively, and the precipitated product was refrigerated. Washing the product with methanol and acetone and drying for several times to obtain the double-bond modified poly-rotaxane cross-linking agent.

S5, mixing the polyrotaxane cross-linking agent and the PCL cross-linking network precursor to form a transparent solution, and then pouring the transparent solution into an open polytetrafluoroethylene circular mold with the diameter of 80 mm. The solution was subjected to a thermal crosslinking reaction at 70 ℃ for 10 hours, and the solvent was partially evaporated to give a gel. And then, drying the gel for 50h at 70 ℃ under vacuum to obtain the high-toughness polycaprolactone remodelable shape memory material.

Specifically, the method is carried out according to the parameters shown in Table 1 in each example

Table 1: experimental parameters for examples 1-3

	Reagent	Example 1	Example 2	Example 3
					Synthesis of PCL	E epsilon-CL/mole ratio	1:50	1:75	1:100
Synthesis of PR	PEG-NH₂Molecular weight/kDa	10	20	35

Thirdly, structural characterization and performance test

FIG. 1 shows a nuclear magnetic hydrogen spectrum (i) and a carbon spectrum (ii) of 4-Me-7-BuOAc-COU and COOH-COU, wherein in the nuclear magnetic hydrogen spectrum, a peak at a chemical shift of 7.4 to 7.7ppm on the hydrogen spectrum of the COOH-COU corresponds to a proton peak near a methyl group on a benzene ring; the peak with the chemical shift of 6.8-7.0 ppm corresponds to the proton peak close to the ether bond on the benzene ring; the peak at the chemical shift of 6.1-6.2 ppm corresponds to the proton peak on the intermediate double bond between the ester bond and the methyl; the peak with the chemical shift of 4.0-4.2 ppm corresponds to the proton peak on the methylene near the ortho-oxygen of the benzene ring; the peak with the chemical shift of 2.4-2.6 ppm corresponds to a proton peak on a methylene near an ester bond between the ester bond and the ether bond and a proton peak of a methyl on a double bond adjacent to the ester bond; compared with a hydrogen spectrum of COOH-COU, a spectrogram of 4-Me-7-BuOAc-COU is basically consistent with the hydrogen spectrum, only an ester bond ortho methylene proton peak with a chemical shift of about 4.0ppm and a proton peak of a methyl group with a chemical shift of about 1.3ppm are added, and the integral result ratio of each group of peak areas is the same as the theoretical ratio. In nuclear magnetic carbon spectrum, the peak positions of the spectra of 4-Me-7-BuOAc-COU and COOH-COU are basically consistent, and only 4-Me-7-BuOAc-COU has a carbon peak with chemical shift of about 60.0ppm adjacent to oxygen atom in the ester bond and a carbon peak on methyl, which are consistent with theoretical prediction. The successful preparation of the carboxyl-containing coumarin can be proved by the nuclear magnetic hydrogen spectrum and the carbon spectrum of 4-Me-7-BuOAc-COU and COOH-COU.

FIG. 2 shows nuclear magnetic hydrogen spectra of synthesized PCL (i) and PCL-COU (ii), in which the peak at 1.32ppm of chemical shift corresponds to the proton peak on the central methylene group of the caprolactone segment; the peak at a chemical shift of 1.58ppm corresponds to the proton peak on the methylene group adjacent to the middle carbon atom in the caprolactone segment; the peak at a chemical shift of 2.24ppm corresponds to the proton peak at the carbon adjacent to the carbonyl group of the caprolactone segment; the peak at a chemical shift of 3.98ppm corresponds to the peak of the proton at the carbon adjacent to the oxygen atom of the caprolactone segment. These four shift values are characteristic peaks for five methylene groups of PCL, indicating successful preparation of linear PCL. The peaks at 7.42ppm, 6.78ppm, 6.73ppm, 6.07ppm, 2.46ppm, 2.08ppm and 1.85ppm in FIG. (ii) are all proton peak shifts of the coumarin group, indicating successful grafting of the carboxycoumarin group onto the PCL.

FIG. 3 shows a comparison of gel permeation chromatograms of pure PCL, PCL-COU and PCL-COU-BP after illumination. The number average molecular weight of the pure PCL is about 15000, and the molecular weight of the modified end group of the pure PCL is about 18000 which is larger than the preset molecular weight; the molecular weight of PCL-COU-BP is multiplied after illumination, which indicates the successful progress of the chain extension reaction.

As shown in FIG. 4, PEG-NH with different molecular weights is selected₂Synthetic PR nuclear magnetic contrast maps. The number of alpha-CD on a single PR, N, was calculated by integrating the characteristic peaks at 4.8ppm and 3.5ppm_(α-CD)And find out how many on averageThe PEG structural unit has an alpha-CD, the number of which is N_(EG)And (4) showing. As shown in FIG. 4, PEG-NH with different molecular weights is selected₂The synthesized PR gel permeation chromatography contrast chart can obtain the molecular weights of different PR, and the molecular weights of different PR are compared with the molecular weight of PR obtained by calculating the nuclear magnetic hydrogen spectrum. This gives 47 α -CDs on PR (10), with an average of one α -CD per 5 PEG building blocks; 143 α -CDs on PR (20), with an average of one α -CD per 3 PEG building blocks; while there were 179 α -CDs on PR (35), with an average of one α -CD per 4.5 PEG building blocks. However, the molecular weight measured by gel permeation chromatography is significantly smaller than that calculated by nuclear magnetic hydrogen spectrum, and it is hypothesized that the molecular weight measured by gel permeation chromatography is smaller because PR is easily adsorbed on the chromatographic column due to a large amount of hydrogen bond interactions on PR, which results in longer outflow time and smaller molecular weight.

Cutting the sample of polycaprolactone remodelable shape memory material with high toughness prepared in S5 into 10X 5X 0.8mm³After the bar is stretched to 1200% strain, it is cooled and fixed in cold water under the strain condition, and then the bar is put into hot water at 70 ℃ to record the shape recovery rate and recovery time, and the following shape memory property test table is obtained, which is detailed in table 2.

TABLE 2 shape memory Performance test Table

From table 2, it can be seen that the material still has excellent shape memory performance under the strain of up to 1200%, the shape recovery rate is above 98%, and the shape recovery rate is within 5s, which indicates that the shape memory material prepared by the method effectively improves the toughness and recovery of the PCL shape memory material.

And (3) putting the sample of the polycaprolactone remodelable shape memory material with high toughness prepared in the step S5 into a custom-made mould, heating the mould at 140 ℃ for 12 hours, and measuring the change of the gel content of the material by using a Soxhlet extraction method, wherein the test data of the gel content are detailed in a table 3.

Table 3 gel content test data are shown in the table below

As can be seen from Table 3, the gel content of the material is greatly reduced after the high-temperature heat treatment at 140 ℃, which indicates that the D-A reaction is reversely performed, and the partial deconstruction of the crosslinking network enables the material to have the capability of permanent shape reconstruction under the solid condition.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and their concepts should be equivalent or changed within the technical scope of the present invention.

Claims

1. A preparation method of a high-toughness polycaprolactone remodelable shape memory material is characterized by comprising the following steps: the method comprises the following steps:

s3: uniformly mixing the modified PCL in the S2 with benzophenone, pressing into a sheet shape, irradiating under ultraviolet light to enable the sheet shape to have chain extension reaction, preparing the PCL with the chain extended by illumination into a solution, and carrying out ultrasonic treatment to prepare the PCL with a conjugated double bond on a main chain;

s5: and uniformly mixing the PCL with the conjugated double bond on the main chain prepared in the S3 and the polyrotaxane crosslinking agent prepared in the S4, and carrying out Diels-Alder reaction at the reaction temperature to crosslink to prepare the high-toughness polycaprolactone remodelable shape memory material.

2. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S5, in the polymer crosslinking system, the molar ratio of the number of conjugated double bonds on PCL to the double bonds on polyrotaxane is: 1:1.

3. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S5, the Diels-Alder reaction temperature was 70 ℃.

4. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S4, the molecular weights of the polyethylene glycol diamine are respectively 10kDa to 35kDa, and a large steric hindrance end-capping agent N-benzyloxycarbonyl-L-tyrosine is selected in the preparation of the polyrotaxane.

5. A method of preparing a high toughness polycaprolactone remodelable shape memory material as claimed in claim 1, wherein: in S4, the double bond-containing polyrotaxane crosslinking agent is obtained by the following method: the alpha-CD group on PR is first hydroxypropyl activated with propylene oxide and then double bond is grafted with 2-ethyl propenyl ethyl isocyanate.

6. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S3, the molar ratio of the amount of the benzophenone to the modified coumarin group at the end of the PCL is 1: 1-1: 2.

7. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: the concentration of the PCL solution prepared in S3 after chain extension by illumination is 0.1-1 mg/mL.

8. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S2, 4- ((4-methyl-2-oxo-2H-chromen-7-yl) oxy) butanoic acid was prepared by the following method: 4-methyl umbelliferone is selected as a raw material, substituted by 4-ethyl bromobutyrate and then hydrolyzed under an alkaline condition.

9. The method of preparing a high toughness polycaprolactone remodelable shape memory material of claim 1, wherein: in S1, in the ring-opening polymerization reaction of epsilon-caprolactone, the molar ratio of ethylene glycol to epsilon-caprolactone is 1: 50-1: 100.

10. The high toughness polycaprolactone remodelable shape memory material made by the process of making the high toughness polycaprolactone remodelable shape memory material of any one of claims 1 to 9.