A biobased degradable one-component elastomeric resin, and a preparation method and application thereof

Abstract

This invention discloses a bio-based biodegradable one-component elastic resin, its preparation method, and its applications. The one-component elastic resin comprises PLA-PCL block copolymer modified polyurethane acrylate, a bio-based reactive diluent, a latent photothermal dual-curing system, and a medical functional additive. The PLA-PCL block copolymer modified polyurethane acrylate uses polylactic acid and polycaprolactone as soft segments and bio-based diisocyanate as hard segments, with acrylate double bonds grafted to the ends of the molecular chains. The bio-based reactive diluent is a compound of lactide-caprolactone copolymer acrylate and bio-based isooctyl acrylate. The latent photothermal dual-curing system includes a blocked bio-based isocyanate and a photoinitiator. The resin of this invention is composed entirely of bio-based raw materials, and the components work synergistically to achieve comprehensive performance including high elasticity, biodegradability, stable one-component storage, and photothermal dual-curing, ensuring the biosafety and controllable degradation of long-term implantation.

Description

Technical Field

[0001] This invention relates to the field of polymer materials technology, and in particular to a bio-based biodegradable single-component elastic resin, its preparation method, and its application. Background Technology

[0002] With the rapid development of bioprinting in tissue engineering, personalized medical devices, and absorbable implants, stringent requirements have been placed on the biocompatibility, biodegradability, elasticity, and ease of use of single-component printing materials. However, current medical 3D printing elastic materials face several bottlenecks: Most mainstream elastic resins are two-component systems, requiring precise on-site mixing and proportioning, resulting in low batch stability and utilization rates, making large-scale production difficult. Traditional polyurethane and acrylate elastic resins are petroleum-based, with degradation products posing biocompatibility risks; some are not completely degradable, and long-term implantation can easily lead to inflammation. Polylactic acid (PLA) is rigid and brittle, while polycaprolactone (PCL) lacks sufficient strength and elasticity; simple blending cannot simultaneously meet the synergistic requirements of elasticity, mechanical strength, and controllable degradation cycles. Existing one-component elastic resins mostly rely on non-bio-based curing agents such as blocked isocyanates, resulting in insufficient biocompatibility and difficulty in balancing degradability and high elasticity. Therefore, developing a fully bio-based, degradable, one-component, highly elastic medical resin suitable for bio-3D printing has become a key technical problem urgently needing to be solved in this field. Summary of the Invention

[0003] This invention provides a bio-based biodegradable single-component elastic resin, its preparation method, and its application, in order to solve the technical problems of poor biocompatibility and degradability of existing medical 3D printing elastic materials.

[0004] In a first aspect, the present invention provides a bio-based biodegradable one-component elastic resin, comprising the following raw materials in parts by mass: PLA-PCL block copolymer modified polyurethane acrylate 45-65 parts; 20-35 parts of bio-based active diluent; 8 to 20 parts of a latent photothermal dual-curing system; 0.5 to 3 parts of medical functional adjuvants; The PLA-PCL block copolymer modified polyurethane acrylate uses polylactic acid and polycaprolactone as soft segments, bio-based diisocyanate as hard segments, and acrylate double bonds grafted to the ends of the molecular chains. The bio-based active diluent is a compound of lactide-caprolactone copolymer acrylate and bio-based isooctyl acrylate; The latent photothermal dual-curing system includes a blocked bio-based isocyanate and a photoinitiator.

[0005] In some of these embodiments, the PLA-PCL block copolymer modified polyurethane acrylate has a number average molecular weight of 2000 g / mol to 8000 g / mol, which gives the prepolymer both good flowability and elasticity after curing, avoiding excessively high viscosity that affects printing accuracy or excessively low viscosity that leads to insufficient strength. The mass ratio of polylactic acid to polycaprolactone is (3~5):(5~7) to balance rigidity and flexibility. The PLA segments provide strength, while the PCL segments contribute elasticity and toughness, synergistically giving the resin suitable hardness, tensile recovery rate and controllable degradation rate. The acrylate double bond content is 0.2mmol / g~0.8mmol / g, which ensures the efficiency of photocuring crosslinking and the precision of one-time molding, while avoiding the material embrittlement caused by excessive crosslinking density, thus balancing elasticity and strength.

[0006] In some embodiments, the method for preparing the PLA-PCL block copolymer modified polyurethane acrylate includes the following steps: Lactide and caprolactone were mixed in a mass ratio of (3~5):(5~7), and 0.1%~0.5% of a tin catalyst was added. The mixture was reacted under nitrogen protection at 130℃~160℃ for 4h~8h. The residual monomers were removed by vacuum drying to obtain PLA-PCL block copolymer diol. With a molar ratio of NCO groups to OH groups of (1.2~1.5):1, bio-based diisocyanate was added to the PLA-PCL block copolymer diol and reacted at 70℃~90℃ for 2h~4h under nitrogen protection; then excess hydroxyethyl acrylate (-OH to -NCO molar ratio of 1.05:1) was added and reacted at 60℃~80℃ for 3h~5h to obtain PLA-PCL block copolymer modified polyurethane acrylate.

[0007] Optionally, the bio-based diisocyanate can be pentamethylene diisocyanate, dimer acid diisocyanate, or L-lysine diisocyanate; the tin catalyst is stannous octoate.

[0008] In some embodiments, the mass ratio of the lactide-caprolactone copolymer acrylate to the bio-based isooctyl acrylate is (2~4):1. The lactide-caprolactone copolymer acrylate is structurally similar and compatible with the main prepolymer, effectively reducing the viscosity of the system and participating in photocuring crosslinking without sacrificing bio-based properties and degradability; the bio-based isooctyl acrylate (monomers derived from biomass, such as vegetable oils, fermented alcohols, etc.) acts as a monofunctional reactive diluent, which can further adjust the viscosity, reduce the curing shrinkage rate, and introduce flexible side chains to improve the elongation at break of the cured product.

[0009] In some embodiments, the blocked bio-based isocyanate is pentamethylene diisocyanate (PDI) using lactic acid or acetylacetone as a blocking agent. PDI is a bio-based aliphatic diisocyanate with superior biocompatibility compared to traditional aromatic isocyanates, and its degradation products pose a low toxicity risk. Lactic acid or acetylacetone, as a bio-based blocking agent, has a suitable desealing temperature, is stably end-capped at room temperature, remains inert during the photoforming stage, and releases isocyanate groups during subsequent desealing in a thermal environment of 80-120°C, reacting with active hydrogen in the system to form a second cross-linked network. After printing, the resin undergoes further heat treatment to enhance its mechanical properties and resilience, while its fully bio-based origin ensures the long-term biocompatibility of the final implant.

[0010] In some embodiments, the method for preparing the blocked bio-based isocyanate includes the following steps: Bio-based diisocyanate and a bio-based blocking agent were mixed at a molar ratio of NCO groups to blocking agent of 1:(1.05~1.2) and reacted under nitrogen protection at 40℃~60℃ for 3h~6h to obtain blocked bio-based isocyanate. A slight excess of blocking agent ensures that the isocyanate groups are fully capped, eliminating the influence of free isocyanate on the storage stability of the photosensitive system. The low-temperature, long-duration reaction avoids the decomposition of the blocking agent, and the resulting product has a decapsulation temperature of 80℃~120℃, which matches well with the post-thermo-curing process window, neither affecting photocuring nor hindering stable secondary crosslinking.

[0011] In some embodiments, the photoinitiator is a mixture of (2,4,6-trimethylbenzoyl)diphenylphosphine oxide (TPO) and 2-hydroxy-2-methyl-1-phenyl-1-propanone (1173) in a mass ratio of (1~3):1, with a total amount of 1 to 5 parts. TPO is a highly efficient acylphosphine oxide initiator with a long absorption wavelength, which is beneficial for deep curing. 1173 is an α-hydroxy ketone initiator, which efficiently initiates surface polymerization. The combination of the two can achieve synchronous and uniform curing from the surface to the interior, avoiding the obstacle of deep cross-linking caused by rapid film formation on the surface. The specific ratio ensures the curing speed and reduces the biocompatibility risks caused by unreacted initiator residues. Moreover, the total amount is low, meeting the strict requirements of interlayer bonding and cytotoxicity in the layer-by-layer deposition process of bio-3D printing.

[0012] In some embodiments, the medical functional adjuvant includes 0.1 to 0.5 parts of a polymerization inhibitor, 0.2 to 1 part of a leveling agent, 0.5 to 1.5 parts of a biocompatible plasticizer, and 0.1 to 0.5 parts of an antioxidant; The polymerization inhibitor includes one or both of p-hydroxyanisole and 4-methoxyphenol, which prolongs the resin's storage life at room temperature. The leveling agent is an organosilicon-based leveling agent, which improves the smoothness of the printed surface. The biocompatible plasticizer includes one or both of tributyl citrate and acetylated tributyl citrate, which enhances the activity of oligomer segments to improve elasticity and is non-toxic to metabolize. The antioxidants include one or both of vitamin E and tea polyphenols, which prevent the material from oxidative degradation during processing and in vivo service.

[0013] Secondly, the present invention also provides a method for preparing a bio-based biodegradable single-component elastic resin, comprising the following steps: Under light-protected and nitrogen-protected conditions, PLA-PCL block copolymer modified polyurethane acrylate, bio-based reactive diluent, and blocked isocyanate were mixed and reacted at 50℃~60℃ for 1h~2h. After cooling to below 40℃, photoinitiator and medical functional additives were added sequentially, and the mixture was stirred for 30min~60min until completely dissolved. The mixture was then filtered through an organic filter membrane and degassed under vacuum for 30min to obtain a bio-based biodegradable single-component elastic resin.

[0014] Thirdly, the present invention also provides an application of bio-based biodegradable single-component elastic resin in 3D printing of bio-products, characterized in that the bio-products include medical implants, tissue engineering scaffolds, and soft tissue repair materials.

[0015] The single-component elastic resin is suitable for DLP / SLA bio-3D printing processes. The printing process parameters include: printing wavelength 405nm, layer thickness 25μm~100μm, exposure time 8s / layer~15s / layer, and post-processing: after printing, the uncured resin is removed by ethanol cleaning, followed by heat post-treatment at 80℃~120℃ for 1h~2h to complete the secondary cross-linking.

[0016] Compared with the prior art, the present invention has the following beneficial effects: This invention uses PLA-PCL block copolymer modified polyurethane acrylate as the elastic backbone. The soft segments are composed of biodegradable polylactic acid and polycaprolactone, while the hard segments are derived from bio-based diisocyanate with acrylate double bonds grafted at the ends, endowing the material with photocuring activity and high elasticity potential. The compounded bio-based reactive diluent has both viscosity-reducing and copolymerization functions. The latent photothermal dual curing system contains blocked bio-based isocyanate and photoinitiator. The blocked isocyanate is inert and stable at room temperature. After rapid curing and molding by photoinitiation of acrylate double bonds, it is unblocked and crosslinked in subsequent heat treatment to form an interpenetrating double network, which greatly improves mechanical strength and resilience. The resin is composed entirely of bio-based raw materials. The components work synergistically to achieve comprehensive performance of high elasticity, biodegradability, stable single-component storage, and photothermal dual curing, which significantly simplifies the bio-3D printing operation process and ensures the biosafety and controllable degradation of long-term implantation. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described in detail below. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] As used herein, the terms “prepared from” and “comprising” are synonymous. The terms “comprising,” “including,” “having,” “containing,” or any other variations thereof, as used herein, are intended to cover non-exclusive inclusion. For example, a composition, step, method, article, or apparatus that includes the listed elements is not necessarily limited to those elements, but may include other elements not expressly listed or elements inherent to such composition, step, method, article, or apparatus.

[0019] When a quantity, concentration, or other value or parameter is expressed as a range, a preferred range, or a range defined by a series of upper and lower preferred values, it should be understood as specifically disclosing all ranges formed by any pair of any upper or preferred value with any lower or preferred value, regardless of whether the range is disclosed individually.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. Unless otherwise specified, the raw materials used in the following examples and comparative examples are commercially available industrial products or prepared by conventional methods, and conditions not specifically stated are conventional conditions. Example 1

[0021] The one-component elastic resin of Example 1 comprises the following parts by weight of raw materials: 55 parts of PLA-PCL block copolymer modified polyurethane acrylate (PLA:PCL=4:6, Mn=5000 g / mol); 28 parts of bio-based reactive diluent (lactide-caprolactone copolymer acrylate: bio-based isooctyl acrylate = 3:1); 12 parts of blocked bio-based isocyanate (PDI-lactic acid end-capped, unsealing temperature 100℃). Three parts of photoinitiator (TPO:1173=2:1); Two parts of medical functional additives (0.2 parts MEHQ, 0.5 parts leveling agent, 1 part ATBC, and 0.3 parts vitamin E); Preparation method of the one-component elastic resin in Example 1: Under light-protected and nitrogen-protected conditions, PLA-PCL block copolymer modified polyurethane acrylate, bio-based reactive diluent, and blocked isocyanate were mixed and reacted at 55°C for 1.5 h. The mixture was then cooled to 38°C, and a photoinitiator and medical functional additives were added sequentially. The mixture was stirred for 30-60 min until completely dissolved. After filtration through a 0.45 μm organic filter membrane and vacuum degassing for 30 min, a bio-based biodegradable single-component elastic resin was obtained.

[0022] 3D printing process of Example 1: The printed product was obtained by printing with a DLP bio 3D printer (405nm), with a layer thickness of 50μm, an exposure time of 10s / layer, and post-treatment at 100℃ / 1.5h. Example 2

[0023] The one-component elastic resin of Example 2 comprises the following parts by weight of raw materials: 50 parts of PLA-PCL block copolymer modified polyurethane acrylate (PLA:PCL=3:7, Mn=6000 g / mol); 32 parts of bio-based reactive diluent (lactide-caprolactone copolymer acrylate: bio-based isooctyl acrylate = 4:1); 10 parts of blocked bio-based isocyanate (PDI-acetylacetone end-capped, unsealing temperature 90℃); Four parts of photoinitiator (TPO:1173=1:1); 1.5 parts of medical functional additives (0.1 parts of MEHQ, 0.4 parts of leveling agent, 0.8 parts of ATBC, and 0.2 parts of vitamin E); The preparation method of the single-component elastic resin in Example 2 is the same as that in Example 1.

[0024] 3D printing process of Example 2: The printed product was obtained by using an SLA bio-3D printer (405nm) with a layer thickness of 75μm, an exposure time of 12s / layer, and a post-treatment at 90℃ for 2h. Example 3

[0025] The one-component elastic resin of Example 3 comprises the following parts by weight of raw materials: PLA-PCL block copolymer modified polyurethane acrylate (PLA:PCL=1:1, Mn=4000 g / mol) 60 parts; 22 parts of bio-based reactive diluent (lactide-caprolactone copolymer acrylate: bio-based isooctyl acrylate = 2:1); 15 parts of blocked bio-based isocyanate (PDI-lactic acid end-capped, unsealing temperature 110℃). Two parts of photoinitiator (TPO:1173=3:1); One part of medical functional additives (0.1 part MEHQ, 0.3 part leveling agent, 0.5 part ATBC, 0.1 part vitamin E); The preparation method of the single-component elastic resin in Example 3 is the same as that in Example 1.

[0026] 3D printing process of Example 3: The printed product was obtained by using a DLP bio-3D printer (405nm) with a layer thickness of 25μm, an exposure time of 8s / layer, and a post-treatment temperature of 110℃ / 1h.

[0027] Comparative Example 1 The difference between Comparative Example 1 and Example 1 is that Comparative Example 1 uses PLA-PCL block copolymer modified polyurethane acrylate, bio-based reactive diluent, photoinitiator, and medical functional additives as component A, and uses an instant-reactive isocyanate curing agent (uncapped PDI trimer) instead of blocked bio-based isocyanate as component B. In use, components A and B are mixed in proportion, stirred for 5 minutes, vacuum degassed, printed, and post-treated at 100°C for 1.5 hours.

[0028] Comparative Example 2 The difference from Example 1 is that Comparative Example 2 uses an equal amount of petroleum-based polyurethane acrylate (synthesized from polytetrahydrofuran diol, isophorone diisocyanate and hydroxyethyl acrylate) instead of PLA-PCL block copolymer modified polyurethane acrylate.

[0029] Comparative Example 3 The difference from Example 1 is that the synthesis method of PLA-PCL block copolymer modified polyurethane acrylate in Comparative Example 3 is changed as follows: PLA diol (Mn=3500) and PCL diol (Mn=3500) are prepared separately, physically mixed at a mass ratio of 4:6, and then reacted with equal amounts of pentamethylene diisocyanate and hydroxyethyl acrylate in a one-pot reaction to obtain polyurethane acrylate.

[0030] Comparative Example 4 The difference from Example 1 is that in Comparative Example 4, the 12 parts of blocked bio-based isocyanate in Example 1 were replaced with an equal amount of bio-based active diluent, so that the system became a pure UV-cured single network.

[0031] Comparative Example 5 The difference from Example 1 is that Comparative Example 5 uses a blocked petroleum-based isocyanate (HDI-butanone oxime-terminated) instead of a blocked bio-based isocyanate.

[0032] Comparative Example 6 The difference from Example 1 is that in Comparative Example 6, the 28 parts of bio-based active diluent in Example 1 were replaced with an equal amount of lactide-caprolactone copolymer acrylate.

[0033] Performance testing 1. Hardness test: A Shore A hardness tester was used to measure the hardness of samples with a thickness ≥ 6 mm at 23±2℃, and the hardness value was read after 5 seconds.

[0034] 2. Tensile property test: Type II dumbbell-shaped specimens were used, with a tensile rate of 50 mm / min. The tensile strength and elongation at break were recorded.

[0035] 3. Rebound rate test: A pendulum elasticity testing machine is used to determine the percentage of the specimen's rebound height after impact.

[0036] 4. Cell viability test: In vitro cytotoxicity test was performed using the CCK-8 method. L929 mouse fibroblasts were used as a model. Cell viability was detected after culturing the extract for 24 hours. Blank culture medium was used as a 100% control.

[0037] 5.6-month degradation rate test: According to the in vitro degradation test method, the sample was immersed in phosphate buffered saline (PBS, pH 7.4) at 37±1℃ for 6 months, and fresh PBS was replaced every two weeks. The degradation percentage was calculated by subtracting the residual mass after drying from the initial mass.

[0038]

[0039] As shown in Table 1, Examples 1 to 3 are non-toxic, completely biodegradable, and suitable for medical products. Example 1 meets medical requirements, Example 2 is suitable for soft tissue repair materials, and Example 3 is suitable for orthopedic implants and tissue engineering scaffolds.

[0040] Comparative Example 1 (two-component instant reactive type) showed a significant decrease in rebound rate and cell survival rate due to on-site mixing errors and uneven reaction; Comparative Example 2 (petroleum-based polyurethane acrylate) had acceptable mechanical properties but a cell survival rate of only 52% and a degradation rate of only 8%, indicating severe deficiencies in biocompatibility and degradability; Comparative Example 3 (one-pot method after simple physical mixing) showed uncontrolled block structure, resulting in comprehensive deterioration of mechanical strength, rebound, and elongation; Comparative Example 4 (pure UV single network) lacked a thermosetting second network, leading to a sharp decrease in tensile strength and rebound rate, and excessively rapid degradation; Comparative Example 5 (petroleum-based blocked isocyanate) showed a cell survival rate reduced to 68% and a degradation rate of 25%, indicating that the non-biologically based curing component posed a biosafety risk; Comparative Example 6 (pure copolymer reactive diluent) had excessively high hardness, a significant decrease in elongation and rebound rate, and a loss of elastic adaptability.

[0041] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0042] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. In particular, it should be noted that any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention for those skilled in the art.

Claims

1. A bio-based biodegradable one-component elastic resin, characterized in that, The ingredients consist of the following parts by weight: PLA-PCL block copolymer modified polyurethane acrylate 45-65 parts; 20-35 parts of bio-based active diluent; 8 to 20 parts of a latent photothermal dual-curing system; 0.5 to 3 parts of medical functional adjuvants; The PLA-PCL block copolymer modified polyurethane acrylate uses polylactic acid and polycaprolactone as soft segments, bio-based diisocyanate as hard segments, and acrylate double bonds grafted to the ends of the molecular chains. The bio-based active diluent is a compound of lactide-caprolactone copolymer acrylate and bio-based isooctyl acrylate; The latent photothermal dual curing system includes a blocked bio-based isocyanate and a photoinitiator.

2. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The PLA-PCL block copolymer modified polyurethane acrylate has a number average molecular weight of 2000 g / mol to 8000 g / mol, a mass ratio of polylactic acid to polycaprolactone of (3~5):(5~7), and an acrylate double bond content of 0.2 mmol / g to 0.8 mmol / g.

3. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The preparation method of the PLA-PCL block copolymer modified polyurethane acrylate includes the following steps: Lactide and caprolactone were mixed in a mass ratio of (3~5):(5~7), a tin catalyst was added, and the mixture was reacted at 130℃~160℃ for 4h~8h under nitrogen protection. The residual monomers were removed by vacuum drying to obtain PLA-PCL block copolymer diol. With a molar ratio of NCO groups to OH groups of (1.2~1.5):1, bio-based diisocyanate was added to the PLA-PCL block copolymer diol and reacted at 70℃~90℃ for 2h~4h under nitrogen protection; then excess hydroxyethyl acrylate was added and reacted at 60℃~80℃ for 3h~5h to obtain PLA-PCL block copolymer modified polyurethane acrylate.

4. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The mass ratio of the lactide-caprolactone copolymer acrylate to the bio-based isooctyl acrylate is (2~4):

1.

5. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The blocked bio-based isocyanate is a pentamethylene diisocyanate using lactic acid or acetylacetone as a blocking agent.

6. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The method for preparing the blocked bio-based isocyanate includes the following steps: Bio-based diisocyanate and bio-based blocking agent are mixed at a molar ratio of NCO group to blocking agent of 1:(1.05~1.2), and reacted at 40℃~60℃ for 3h~6h under nitrogen protection to obtain blocked bio-based isocyanate.

7. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The photoinitiator is a compound of (2,4,6-trimethylbenzoyl)diphenylphosphine oxide and 2-hydroxy-2-methyl-1-phenyl-1-propanone in a mass ratio of (1~3):1, with a total amount of 1 to 5 parts.

8. The bio-based biodegradable single-component elastic resin as described in claim 1, characterized in that, The medical functional adjuvant includes 0.1 to 0.5 parts of a polymerization inhibitor, 0.2 to 1 part of a leveling agent, 0.5 to 1.5 parts of a biocompatible plasticizer, and 0.1 to 0.5 parts of an antioxidant; The polymerization inhibitor includes one or both of p-hydroxyanisole and 4-methoxyphenol; The leveling agent is an organosilicon-based leveling agent; The biocompatible plasticizer includes one or both of tributyl citrate and acetylated tributyl citrate; The antioxidants include one or both of vitamin E and tea polyphenols.

9. A method for preparing a bio-based biodegradable single-component elastic resin as described in any one of claims 1 to 8, characterized in that, Includes the following steps: Under light-protected and nitrogen-protected conditions, PLA-PCL block copolymer modified polyurethane acrylate, bio-based reactive diluent, and blocked isocyanate were mixed and reacted at 50℃~60℃ for 1h~2h. After cooling to below 40℃, photoinitiator and medical functional additives were added sequentially, and the mixture was stirred for 30min~60min until completely dissolved. The mixture was then filtered through an organic filter membrane and degassed under vacuum for 30min to obtain a bio-based biodegradable single-component elastic resin.

10. The application of a bio-based biodegradable single-component elastic resin as described in any one of claims 1 to 8 in 3D printing of bio-products, characterized in that, The bioproducts include medical implants, tissue engineering scaffolds, and soft tissue repair materials.

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