Light-curable polyurethane and bio-oil-based phosphate elastomer synergistically modified high-volume rubber powder asphalt and preparation method thereof

Abstract

The invention discloses light-curable polyurethane and bio-oil-based phosphate elastomer synergistically modified high-volume rubber powder asphalt and a preparation method thereof, and belongs to the technical field of road engineering, and the preparation method comprises the following steps: carrying out a decrosslinking reaction on rubber powder to obtain desulfurized rubber powder; the method comprises the following steps: pre-reacting bio-oil and polyphosphoric acid to generate bio-oil-based phosphate; the preparation method comprises the following steps: carrying out prepolymerization, chain extension reaction and polymerization reaction on polyhydric alcohol and isocyanate to generate photocurable polyurethane; the desulfurized rubber powder, bio-oil-based phosphate and light-curable polyurethane are used for modifying the high-mixing-amount rubber powder asphalt, and the bio-oil-based phosphate / light-curable polyurethane / high-mixing-amount rubber powder modified asphalt is obtained. According to the preparation method of the photo-curable polyurethane and bio-oil-based phosphate elastomer synergistically modified high-volume rubber powder asphalt, through innovative component design and process control, the high-temperature stability, low-temperature toughness and construction performance of the modified asphalt are synergistically optimized, and high-efficiency and high-value utilization of the waste tire rubber powder is realized.

Description

Technical Field

[0001] This invention relates to the field of road engineering technology, and in particular to a high-content asphalt powder modified by photocurable polyurethane and bio-oil-based phosphate elastomer, and its preparation method. Background Technology

[0002] In solid waste management, the disposal of waste tires is a global environmental challenge. Globally, over one billion tons of waste tires are generated annually. Their main component, vulcanized rubber, has a stable three-dimensional cross-linked network structure, making it difficult to reprocess using conventional melting processes. Open-air stockpiling of waste tires easily leads to fires and releases harmful substances, while landfilling occupies vast amounts of land. Therefore, the efficient recycling and resource utilization of waste tires is crucial.

[0003] Grinding waste tires into crumb rubber (CR) and using it for asphalt modification is a promising and efficient recycling method. CR-modified asphalt not only significantly improves the rutting resistance, elastic recovery, fatigue resistance, aging resistance, and low-temperature crack resistance of asphalt pavements, but also allows for the large-scale utilization of waste tire resources. However, the CR content in conventional rubberized asphalt is generally less than 20%. Although desulfurization pretreatment of CR can increase its content and improve asphalt storage stability, it weakens the cross-linking structure of CR, leading to a significant decrease in the high-temperature performance and resistance to permanent deformation of the modified asphalt. Simply increasing the amount of CR powder can enhance high-temperature performance, but it will drastically increase the viscosity of the asphalt, seriously affecting its workability.

[0004] Currently, among the main strategies for improving the performance of high-content rubber powder asphalt, adding softeners such as bio-oil can effectively reduce high viscosity and improve low-temperature ductility, while adding polyphosphoric acid can enhance high-temperature performance. However, the existing technologies for adding bio-oil and polyphosphoric acid, their proportions, and interaction mechanisms are still insufficient to synergistically and effectively optimize the high-temperature stability, low-temperature ductility, crack resistance, and construction viscosity of high-content rubber powder modified asphalt. Existing technologies lack preparation methods that can balance its high-temperature performance, low-temperature toughness, and construction viscosity, necessitating the development of innovative formulations and processes to synergistically improve overall performance, meet road application requirements, and achieve efficient and high-value utilization of waste tires. Summary of the Invention

[0005] The purpose of this invention is to provide a method for synergistic modification of high-content rubber powder asphalt by photocurable polyurethane and bio-oil-based phosphate elastomer, and its preparation method. Through innovative component design and process control, the high-temperature stability, low-temperature toughness and construction performance of the modified asphalt are synergistically optimized, thereby achieving efficient and high-value utilization of waste tire rubber powder.

[0006] To achieve the above objectives, this invention provides a method for preparing high-content rubber powder asphalt synergistically modified with photocurable polyurethane and bio-oil-based phosphate elastomer, comprising the following steps: S1. Premix the rubber powder with the decrosslinking agent, and then carry out the decrosslinking reaction to obtain desulfurized rubber powder. Wash and dry the desulfurized rubber powder to obtain dry desulfurized rubber powder, denoted as DCR. S2. Mix bio-oil and polyphosphoric acid, stir and react to obtain bio-oil-based phosphate ester; S3. Prepolymerize polyol and isocyanate, then add chain extender to carry out chain extension reaction, and after the chain extension reaction is completed, add photoinitiator to carry out polymerization reaction to obtain photocurable polyurethane. S4. Mix and stir the DCR obtained in S1, the bio-oil-based phosphate ester obtained in S2, and the light-curable polyurethane obtained in S3 with the base asphalt. After mixing, shear emulsify the mixture and then irradiate it with light to obtain bio-oil-based phosphate ester / light-curable polyurethane / high-content rubber powder modified asphalt.

[0007] Preferably, in S1, the decrosslinking agent includes 3,6-dioxa-1,8-octanedithiol, dithiothreitol, or 2,2'-dibenzoylaminodiphenyldisulfide.

[0008] Preferably, in S1, the mass ratio of rubber powder to decrosslinking agent is 3-5:100, the premixing temperature is 90-110℃, the premixing stirring rate is 60-80 rpm, the premixing time is 10-15 min, the decrosslinking reaction temperature is 190-210℃, the solvent used for washing the desulfurized rubber powder is anhydrous ethanol, the drying temperature is 50-60℃, and the drying time is 12-15 h.

[0009] Preferably, in S2, the bio-oil includes epoxidized soybean oil, blended crude oil, soybean oil, or epoxidized linseed oil.

[0010] Preferably, in S2, the mass ratio of bio-oil to polyphosphoric acid is 0.5-1.5:1, the stirring rate is 20-50 rpm, the reaction time is 120-180 s, and the reaction temperature is 20-30℃.

[0011] Preferably, in S3, the polyol includes polyester polyol, polycaprolactone polyol or polycarbonate diol, the isocyanate includes toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate or isophorone diisocyanate, the chain extender includes small molecule diol chain extender, small molecule diamine chain extender or 2-hydroxyethyl methacrylate, and the photoinitiator includes methyl benzoylformate, 2-hydroxy-2-methyl-1-phenyl-1-propanone, diphenyl[4-(phenylthio)phenyl]-sulfonium hexafluoroantimonate or 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylphenylpropanone.

[0012] Preferably, in S3, the mass of the polyol is 25-32g, the mass of the isocyanate is 10-15g, the prepolymerization temperature is 75-80℃, the prepolymerization time is 90-120min, the volume of the chain extender is 5-6mL, the chain extension reaction temperature is 65-70℃, the chain extension reaction time is 50-60min, the mass of the photoinitiator is 0.4-0.6g, and the polymerization reaction time is 20-30min.

[0013] Preferably, in S4, the base asphalt includes No. 70 asphalt or No. 90 asphalt.

[0014] Preferably, in S4, the mass ratio of DCR, bio-oil-based phosphate ester, photocurable polyurethane, and matrix asphalt is 3.5-4:0.2-0.4:0.1-0.5:10, the mixing temperature is 180-210℃, the mixing time is 40-60 min, the stirring rate is 1000-1300 rpm, the shear emulsification temperature is 180-210℃, the shear emulsification time is 50-60 min, the shear emulsification rate is 4500-5000 rpm, and the light irradiation process is first ultraviolet light irradiation for 1.5-2 h, followed by natural light irradiation for 168-170 h.

[0015] The present invention also provides a high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer, which is prepared by the above-mentioned preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer.

[0016] Therefore, the present invention employs the above-mentioned method for synergistic modification of high-content rubber powder asphalt with photocurable polyurethane and bio-oil-based phosphate elastomer, and its preparation method, which has the following beneficial effects: (1) In this invention, bio-oil and polyphosphoric acid are pre-reacted for 2-3 minutes to generate bio-oil-based phosphate ester. This product replaces the traditional direct mixing method of addition. Its phosphate ester groups preferentially bond with the polar groups on the surface of the adhesive powder to form a discrete network structure, which effectively solves the problem of increased viscosity caused by continuous network.

[0017] (2) The present invention introduces a photocurable polyurethane prepolymer, which maintains a low viscosity fluid state during the high temperature (160~180℃) construction stage. After irradiation triggers crosslinking to form an interpenetrating network, the synergistic discrete network enables the rubber powder to maintain a rotational viscosity of ≤4.0 Pa·s at 180℃ when the rubber powder content is 35~40 wt%, which meets the requirements of high temperature construction. Moreover, the softening point can reach 90℃ without the addition of styrene-butadiene block copolymer (SBS). At the same time, the processing temperature of this system is only 180~190℃, which is significantly lower than the traditional simple blending system of bio-oil / polyphosphoric acid / rubber powder. While ensuring low viscosity and high softening point, it has more advantages in energy saving and process adaptability.

[0018] (3) The preparation method of the present invention is simple to operate and highly universal, and the process parameters are easy to control. It can consume a large amount of waste rubber, and the processing temperature is low. It has excellent performance and is expected to solve the problem of high viscosity and insufficient high temperature performance of rubber powder modified asphalt at high dosage.

[0019] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0020] Figure 1 These are the gel permeation chromatography and infrared chromatograms of the bio-oil-based phosphate ester prepared in Example 1 of this invention. Detailed Implementation

[0021] The technical solution of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0022] Unless otherwise defined, the technical or scientific terms used in this invention shall have the ordinary meaning as understood by one of ordinary skill in the art to which this invention pertains.

[0023] Example 1 This invention provides a method for preparing high-content rubber powder asphalt synergistically modified with photocurable polyurethane and bio-oil-based phosphate elastomer, comprising the following steps: S1. Take 200g of 30-mesh waste radial tire rubber powder and premix it with 6g of 2,2'-dibenzoylaminodiphenyl disulfide. The premixing temperature is 100℃, and the mixture is stirred at 80rpm for 12min using a Hacker internal mixer. Then, the cross-linking reaction is carried out at 190℃ using a twin-screw extruder at 50rpm to obtain desulfurized rubber powder. The desulfurized rubber powder is washed with anhydrous ethanol and then dried in an oven at 50℃ for 12h to obtain dried desulfurized rubber powder, denoted as DCR. S2. Take 8g of soybean oil and 8g of polyphosphoric acid, mix them, and stir at 30rpm for 180s at room temperature to obtain bio-oil-based phosphate ester. S3. Prepolymerize 25g of polyester polyol and 10g of toluene diisocyanate at 80℃ for 100min, then add 5mL of small molecule diol chain extender and carry out chain extension reaction at 70℃ for 60min; after the chain extension reaction is completed, add 0.5g of methyl benzoate and carry out polymerization reaction for 20min to obtain photocurable polyurethane. S4. Take 160g of DCR obtained in S1, 16g of bio-oil-based phosphate ester obtained in S2, 5g of photocurable polyurethane obtained in S3, and 400g of No. 90 asphalt. Mix them at 190℃ and stir at 1200rpm for 60min. Then, shear emulsify the mixture at 190℃ for 5000rpm for 60min. After that, irradiate with ultraviolet light for 1.5h and with natural light for 7 days to obtain the product bio-oil-based phosphate ester / photocurable polyurethane / high-content rubber powder modified asphalt.

[0024] Example 2 The operation of this embodiment is the same as that of embodiment 1, except that the amount of photocurable polyurethane added in S4 is 20g.

[0025] Comparative Example 1 The operation of this comparative example is the same as that of Example 1, except that S2 and S3 are not performed, and only 160g of DCR and 400g of No. 90 asphalt are added in S4.

[0026] Comparative Example 2 The operation of this comparative example is the same as that of comparative example 1, except that 160g of DCR, 8g of soybean oil and 400g of No. 90 asphalt are added to S4.

[0027] Comparative Example 3 The operation of this comparative example is the same as that of comparative example 1, except that 160g of DCR, 8g of polyphosphate and 400g of No. 90 asphalt are added to S4.

[0028] Comparative Example 4 This embodiment operates the same as Comparative Example 1, except that S3 is omitted, and 160g of DCR, 16g of bio-oil-based phosphate ester, 8g of SBS, and 400g of No. 90 asphalt are added in S4.

[0029] Comparative Example 5 This embodiment operates the same as Comparative Example 1, except that 160g of DCR, 8g of soybean oil, 8g of polyphosphoric acid, 8g of SBS and 400g of No. 90 asphalt are added to S4.

[0030] Comparative Example 6 This embodiment operates the same as Comparative Example 1, except that S3 is omitted, and 160g of DCR, 16g of bio-oil-based phosphate ester, and 400g of No. 90 asphalt are added in S4.

[0031] Comparative Example 7 This embodiment operates the same as Comparative Example 1, except that 160g of DCR, 8g of soybean oil, 8g of polyphosphoric acid, and 400g of No. 90 asphalt are added to S4.

[0032] Take 3g of the DCR prepared in Example 1, dissolve it in 150mL of toluene, and extract it using a Soxhlet extractor to obtain a sol content of 25%.

[0033] The product of the reaction between soybean oil and polyphosphoric acid in Example 1, bio-oil-based phosphate ester, was analyzed by gel permeation chromatography and infrared spectroscopy. The results are as follows: Figure 1 As shown, where Figure 1 In the image, 'a' is the gel permeation chromatogram of bio-oil-based phosphate esters, and 'b' and 'c' are the infrared chromatograms of bio-oil-based phosphate esters. Figure 1 As can be seen from b and c, the infrared peak is at 2920 cm⁻¹. -1 and 2850 cm -1 The weakening at this point indicates that the fatty chain of soybean oil is degraded or restricted, while at 1745 cm -1 The peak value at 1208 cm⁻¹ weakens, indicating a decrease in COC, and... -1 P=O bond, 1035 cm -1 and 1069 cm -1 The presence of POC indicates that an transesterification reaction has occurred; from Figure 1 As can be seen from 'a' in the gel permeation chromatography curve, a new set of peaks appeared in the main peak of bio-oil-based phosphate ester, indicating that new polymers were generated, producing phosphorylated ester compounds or oligomers with larger molecular weights and stronger polarity.

[0034] The products of Examples 1-2 and Comparative Examples 1-7 were evaluated for low-temperature toughness using a 5℃ ductility test. The results are shown in Table 1. As can be seen from Table 1, compared with Comparative Example 1, the ductility of Example 1 increased by 8.57%, the ductility of Comparative Example 4 increased by 129.5%, and the ductility of Comparative Example 5 increased by 58.1%.

[0035] The softening point test was used to characterize the high-temperature stability of the products of Examples 1-2 and Comparative Examples 1-7. The results are shown in Table 1. As can be seen from Table 1, compared with Comparative Examples 1 and 2, the softening point of Example 1 increased by 19.9% ​​and 27.6%, respectively, and the softening point of Example 2 increased by 16.1% and 23.5%, respectively. Compared with Comparative Examples 4 and 5, which are modified asphalt with added SBS, the softening point of Example 1 increased by 9.6% and 7.0%, respectively, and the softening point of Example 2 increased by 6.1% and 3.3%, respectively.

[0036] The processing properties of the products of Examples 1-2 and Comparative Examples 1-7 were evaluated by rotational viscosity at 180°C. The results are shown in Table 1. As can be seen from Table 1, the viscosity of the products of Comparative Examples 3-7 and Examples 1-2 increased to varying degrees compared with the pure DCR modified asphalt of Comparative Example 1. This is because the addition of polymers creates cross-linked structures, which restricts molecular flow and thus increases viscosity. Compared with Comparative Example 3, the viscosity of Example 1 decreased by 26.5%, and the viscosity of Example 2 decreased by 26.6%.

[0037] The hardness of the products from Examples 1-2 and Comparative Examples 1-7 was characterized using a 25°C penetration test. The results are shown in Table 1. Table 1 shows that compared to the pure DCR modified asphalt in Comparative Example 1, the penetration of Example 1 increased by 38.9%, and the penetration of Example 2 increased by 15.3%. Compared to the SBS-modified asphalts in Comparative Examples 4 and 5, the penetration of Example 1 decreased by 5.7% and 1.9%, respectively, and the penetration of Example 2 decreased by 21.7% and 18.8%, respectively. Compared to Comparative Example 3, the penetration of Example 1 increased by 10.7%, and the penetration of Example 2 decreased by 8.3%. A lower penetration indicates harder asphalt and higher strength, but low-temperature brittleness may increase; excessive penetration results in softer asphalt that is prone to deformation at high temperatures. The 25°C penetration of Example 1 is 59.9 × 0.1 mm, which meets the requirement of 40-60 × 0.1 mm in road engineering, while the 25°C penetration of Comparative Examples 4-7 is greater than 60 × 0.1 mm.

[0038] Elastic recovery tests were used to characterize the deformation recovery capabilities of the products from Examples 1-2 and Comparative Examples 1-7, and the results are shown in Table 1. Table 1 shows that compared to the pure DCR modified asphalt of Comparative Example 1, the elastic recovery of Example 1 decreased by 6.4%, and the elastic recovery of Example 2 decreased by 6.4%. Compared to the SBS-modified asphalt of Comparative Examples 4 and 5, the elastic recovery of Example 1 decreased by 12.3% and 11.0%, respectively, and the elastic recovery of Example 2 decreased by 12.3% and 11.0%, respectively. Compared to Comparative Example 3, the elastic recovery of Example 1 decreased by 7.4%, and the elastic recovery of Example 2 decreased by 7.4%. Compared to Comparative Example 6, the elastic recovery of Example 1 decreased by 5.0%, and the elastic recovery of Example 2 decreased by 5.0%. Although the elastic recovery of the examples decreased, their recovery rates were still greater than 80%.

[0039] Table 1 Physical properties of the products from Examples 1-2 and Comparative Examples 1-7

[0040] In summary, although Comparative Example 4 demonstrated outstanding performance in low-temperature toughness and elastic recovery, and Comparative Example 3 outperformed some groups in high-temperature stability, Example 1 achieved balanced optimization in key indicators: ductility at 5℃ reached 11.4 cm (meeting low-temperature crack resistance requirements), softening point reached 90.1℃ (optimal high-temperature stability), viscosity at 180℃ was 3.6 Pa·s (meeting construction requirements), and penetration at 25℃ was 59.9 × 0.1 mm (reasonable balance between hardness and softness), while maintaining an elastic recovery rate of 82.0% at 25℃. Therefore, Example 1 exhibits the best overall performance, with its product possessing excellent low-temperature toughness, high-temperature performance, construction performance, and elastic recovery performance. Furthermore, it can process large quantities of waste tires, enabling resource reuse and fulfilling the national development plan for the recycling of waste tires.

[0041] Therefore, this invention employs the above-mentioned method for synergistic modification of high-content rubber powder asphalt with photocurable polyurethane and bio-oil-based phosphate elastomer and its preparation method. Through innovative component design and process control, the high-temperature stability, low-temperature toughness and construction performance of the modified asphalt are synergistically optimized, thereby achieving efficient and high-value utilization of waste tire rubber powder.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A method for preparing high-content rubber powder asphalt synergistically modified with photocurable polyurethane and bio-oil-based phosphate elastomer, characterized in that: Includes the following steps: S1. Premix the rubber powder with the decrosslinking agent, and then carry out the decrosslinking reaction to obtain desulfurized rubber powder. Wash and dry the desulfurized rubber powder to obtain dry desulfurized rubber powder, denoted as DCR. S2. Mix bio-oil and polyphosphoric acid, stir and react to obtain bio-oil-based phosphate ester; S3. Prepolymerize polyol and isocyanate, then add chain extender to carry out chain extension reaction, and after the chain extension reaction is completed, add photoinitiator to carry out polymerization reaction to obtain photocurable polyurethane. S4. Mix and stir the DCR obtained in S1, the bio-oil-based phosphate ester obtained in S2, and the light-curable polyurethane obtained in S3 with the base asphalt. After mixing, shear emulsify the mixture and then irradiate it with light to obtain bio-oil-based phosphate ester / light-curable polyurethane / high-content rubber powder modified asphalt.

2. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S1, the decrosslinking agent includes 3,6-dioxa-1,8-octanedithiol, dithiothreitol, or 2,2'-dibenzoylaminodiphenyldisulfide.

3. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S1, the mass ratio of rubber powder to decrosslinking agent is 3-5:100, the premixing temperature is 90-110℃, the premixing stirring rate is 60-80 rpm, the premixing time is 10-15 min, the decrosslinking reaction temperature is 190-210℃, the solvent used for washing the desulfurized rubber powder is anhydrous ethanol, the drying temperature is 50-60℃, and the drying time is 12-15 h.

4. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S2, bio-oils include epoxidized soybean oil, blended crude oil, soybean oil, or epoxidized linseed oil.

5. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S2, the mass ratio of bio-oil to polyphosphoric acid is 0.5-1.5:1, the stirring speed is 20-50 rpm, the reaction time is 120-180 s, and the reaction temperature is 20-30℃.

6. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S3, the polyols include polyester polyols, polycaprolactone polyols, or polycarbonate diols; the isocyanates include toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, or isophorone diisocyanate; the chain extenders include small molecule diol chain extenders, small molecule diamine chain extenders, or 2-hydroxyethyl methacrylate; and the photoinitiators include methyl benzoylformate, 2-hydroxy-2-methyl-1-phenyl-1-propanone, diphenyl[4-(phenylthio)phenyl]-sulfonium hexafluoroantimonate, or 2-hydroxy-4′-(2-hydroxyethoxy)-2-methylphenylpropanone.

7. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S3, the mass of the polyol is 25-32g, the mass of the isocyanate is 10-15g, the prepolymerization temperature is 75-80℃, the prepolymerization time is 90-120min, the volume of the chain extender is 5-6mL, the chain extension reaction temperature is 65-70℃, the chain extension reaction time is 50-60min, the mass of the photoinitiator is 0.4-0.6g, and the polymerization reaction time is 20-30min.

8. The preparation method of high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S4, the base asphalt includes No. 70 asphalt or No. 90 asphalt.

9. The method for preparing high-content rubber powder asphalt synergistically modified by photocurable polyurethane and bio-oil-based phosphate elastomer according to claim 1, characterized in that: In S4, the mass ratio of DCR, bio-oil-based phosphate ester, photocurable polyurethane, and matrix asphalt is 3.5-4:0.2-0.4:0.1-0.5:

10. The mixing temperature is 180-210℃, the mixing time is 40-60 min, the stirring rate is 1000-1300 rpm, the shear emulsification temperature is 180-210℃, the shear emulsification time is 50-60 min, the shear emulsification rate is 4500-5000 rpm, and the light irradiation process is as follows: first, irradiate with ultraviolet light for 1.5-2 h, then irradiate with natural light for 168-170 h.

10. A high-content asphalt powder synergistically modified with photocurable polyurethane and bio-oil-based phosphate elastomer, characterized in that: The high-content rubber powder asphalt was prepared by the method described in any one of claims 1-9, which is a photocurable polyurethane and a bio-oil-based phosphate elastomer synergistic modification method.

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