A degradable polymer part suitable for 3D printing and preparation method thereof
By synthesizing acrylate crosslinking agent and small molecule polyethylene glycol, controlling the 3D printing precursor solution parameters, the problem of difficult polymer degradation after photocuring 3D printing is solved, and a rapid degradable and adjustable polymer preparation is achieved.
Patent Information
- Application Number
- CN202310496233.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-05-04
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2043-05-04
AI Technical Summary
After existing photocuring 3D printing, crosslinked polymers are not easily degraded, resulting in environmental and economic problems, and lack of simple and universal degradable photopolymer materials.
The acrylic crosslinking agent is synthesized by reaction of dopamine hydrochloride and polyethylene glycol bisacrylate, combining small molecule polyethylene glycol, controlling the 3D printing precursor solution parameters, regulating the polymer degradation rate, and using water as a degradation solvent to accelerate the degradation reaction.
Obtain rapid degradation, degradation and controllable polymer products, accelerate degradation speed and controllable degradation process, suitable for 3D printing.
Smart Images
Figure CN116640246B_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the field of material technology and relates to the preparation of 3D printing liquid resin materials, and specifically to a degradable polymer part suitable for 3D printing and a preparation method thereof. Background Art
[0002] 3D printing, also known as additive manufacturing, is a general term for various printing processes. It's a rapid prototyping technology that can transform complex three-dimensional models into physical parts without the need for molds or fixtures. This technology integrates CAD, CNC, materials, electronics, and laser technologies, enabling an integrated process from prototyping to production. Since its concept was first proposed in the 1980s, 3D printing has rapidly developed, expanding its application beyond traditional manufacturing to include flexible electronics, biomedicine, aerospace, and other industries.
[0003] 3D printing technology can be divided into two categories based on the forming process. One is laser-based or high-energy-density heat source-based forming technologies, including digital light processing (DLP), layered object manufacturing (LOM), selective laser sintering (SLS), and selective laser melting (SLM). The other is jet-based forming technologies, including fused deposition modeling (FDM) and three-dimensional printing (3DP). Stereolithography is the earliest and most mature 3D printing technology. It is based on photopolymerization technology, using a photosensitive liquid resin as the raw material. Under computer control, a radiation light source scans the surface of each layered cross-section point by point. The radiation light triggers a chain chemical reaction in the scanned area, causing low-molecular-weight monomers or oligomers to cross-link and polymerize to form a dense three-dimensional solid. This polymerization reaction solidifies to form a thin cross-section of the part. After each layer is cured, the workbench moves down by the thickness of the layer, and a new layer of photosensitive resin is applied on top of the previously cured resin, allowing for repeated scanning and curing cycles until the part is complete. In the photocuring process, the rapid liquid-solid transition under light irradiation often requires thermosetting resins with bifunctional or multifunctional monomers and cross-linking via covalent bonds to achieve 3D printing. However, after photocuring 3D printing, the cross-linked polymer network is not easily degraded, which leads to some economic and environmental problems.
[0004] Polymer degradation includes irreversible structural and morphological changes and fragmentation into smaller residues. Under natural conditions, degradation can be induced by chemical and physical processes (such as photooxidation, thermal activation, hydrolysis, mechanical stress) or biological activity. With the rapid development of 3D printing technology, the demand for polymer materials such as resins used in 3D printing continues to increase, and the environmental load caused by a large number of polymer products in the entire life cycle, including production, application and recycling, is also becoming increasingly serious. Therefore, the development of new degradable polymer materials to replace traditional materials has become an urgent problem to be solved in the application of polymer materials. To date, most of the reported reprocessable materials for photocuring 3D printing are composed of multiple components or complex structures, which limits their applicability and increases production costs. There is still a lack of a universal and simple method to design fully degradable photopolymers for 3D printing. Summary of the Invention
[0005] To address the shortcomings of the aforementioned background technology, primarily addressing the fact that cross-linked polymer parts in existing photocuring 3D printing are not easily degraded, which can lead to economic and environmental problems, the present invention provides a method for preparing degradable polymer parts suitable for 3D printing. This method synthesizes a degradable photosensitive acrylate monomer for photocuring 3D printing, combines it with a small molecule polyethylene glycol, and modulates the polymer degradation rate by controlling the raw material parameters of the 3D printing precursor solution, thereby obtaining a polymer part with rapid and controllable degradation.
[0006] In order to achieve the above objectives, the present invention provides a first aspect of a method for preparing a degradable polymer part suitable for 3D printing, comprising the following steps:
[0007] An acrylate-based crosslinker is obtained by reacting dopamine hydrochloride with polyethylene glycol diacrylate;
[0008] Mixing a monomer mixture including the cross-linking agent and a photoinitiator to form a 3D printing precursor solution, and obtaining a polymer part with a three-dimensional structure after 3D printing and curing;
[0009] The three-dimensional structured polymer article can be dissolved in an aqueous solution into a liquid state.
[0010] Preferably, the monomer mixture further comprises polyethylene glycol.
[0011] More preferably, the mass ratio of polyethylene glycol to the cross-linking agent in the monomer mixture is 1:1-10.
[0012] Preferably, the photoinitiator accounts for 0.5-1.5% of the total mass of the monomer mixture; wherein the photoinitiator is (2,4,6-trimethylbenzoyl)diphenylphosphine oxide or phenyl (2,4,6-trimethylbenzoyl) lithium phosphate.
[0013] Preferably, the raw materials for preparing the 3D printing precursor solution further include a water solvent; the water solvent accounts for 1% to 80% of the total mass of the monomer mixture.
[0014] Preferably, the temperature of the aqueous solution is 25-50°C.
[0015] Preferably, the molar ratio of dopamine hydrochloride to polyethylene glycol diacrylate is 1:0.5-1.5.
[0016] A second aspect of the present invention provides a degradable polymer part suitable for 3D printing, which is prepared by the above-mentioned preparation method; the polymer part can be dissolved into a liquid state in an aqueous solution.
[0017] Compared with the prior art, the present invention has the following beneficial effects:
[0018] The present invention provides a degradable polymer component suitable for 3D printing and a preparation method thereof. The method synthesizes a degradable photosensitive acrylate monomer for photocurable 3D printing, combines it with small molecule polyethylene glycol, and regulates the polymer degradation rate by controlling the raw material parameters of the 3D printing precursor solution. The small molecule polyethylene glycol is physically entangled in the cross-linked network, reducing the cross-linking density of the polymer network, thereby accelerating the degradation rate. Water, as a solvent for the degradation reaction, while reducing the cross-linking density, penetrates into the interior of the polymer, causing the degradation reaction to proceed simultaneously on the surface and inside the material, greatly accelerating the degradation reaction. In addition, the hydrophilicity of the polyethylene glycol itself is conducive to the degradation reaction. Ultimately, a polymer component with rapid degradation and controllable degradation is obtained. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] Figure 1 It is a specific flow chart implemented by the present invention.
[0020] Figure 2 It is the chemical formula of PEG575-Do.
[0021] Figure 3 It is PEG575-Do 1 H NMR spectrum.
[0022] Figure 4 It is the chemical formula for the hydrolysis of PEG575-Do.
[0023] Figure 5 These are the spline degradation curves of the polymer parts provided in Examples 1 to 4.
[0024] Figure 6 The polymer strip prepared in Example 5 is used 1 H NMR spectrum tracking the degradation process.
[0025] Figure 7 This is a microstructural view of the degradation process of the polymer strip prepared in Example 1.
[0026] Figure 8 The figure is a comparison of the degradation conditions of the polymer strips provided in Examples 1 to 4.
[0027] Figure 9 1 is the degradation curve of the polymer sample strips provided in Example 1, Example 6 and Example 7. DETAILED DESCRIPTION
[0028] In order to enable those skilled in the art to better understand and implement the technical solution of the present invention, the present invention is further described below with reference to specific embodiments and drawings, but the embodiments are not intended to limit the present invention.
[0029] The present invention provides a method for preparing a degradable polymer part suitable for 3D printing, see Figure 1 As shown, the following steps are included:
[0030] Acrylate-based crosslinker (PEG575-Do) was obtained by reacting dopamine hydrochloride with polyethylene glycol diacrylate (PEGDA575);
[0031] A monomer mixture including the crosslinking agent (PEG575-Do) and a photoinitiator are mixed to form a 3D printing precursor solution, and a polymer part with a three-dimensional structure is obtained after 3D printing and curing;
[0032] The three-dimensional structured polymer article can be dissolved in an aqueous solution into a liquid state.
[0033] The present invention provides a biodegradable polymer component suitable for 3D printing. A biodegradable photosensitive acrylate monomer for photocurable 3D printing is synthesized primarily through an aza-Michael addition reaction. By controlling parameters such as the monomer ratio and solvent ratio, the polymer degradation rate is regulated, resulting in a polymer network with rapid and controllable degradation, which can be used for DLP 3D printing. This material exhibits rapid degradation, adjustable degradation properties, and 3D printing capabilities.
[0034] The monomer mixture further comprises polyethylene glycol (PEG400), and the mass ratio of polyethylene glycol to the cross-linking agent (PEG575-Do) in the monomer mixture is 1:1-10.
[0035] Furthermore, the photoinitiator accounts for 0.5 to 1.5% of the total mass of the monomer mixture; wherein the photoinitiator is (2,4,6-trimethylbenzoyl) diphenylphosphine oxide or phenyl (2,4,6-trimethylbenzoyl) lithium phosphate.
[0036] During the preparation of the present invention, the raw materials for preparing the 3D printing precursor solution also include a water solvent; the water solvent accounts for 1% to 80% of the total mass of the monomer mixture.
[0037] In the present invention, the temperature of the aqueous solution is 25-50° C., which facilitates the rapid degradation of the three-dimensional polymer component.
[0038] In the present invention, in the process of preparing the cross-linking agent, the molar ratio of dopamine hydrochloride to polyethylene glycol diacrylate is 1:0.5-1.5.
[0039] A second aspect of the present invention provides a degradable polymer part suitable for 3D printing, which is prepared by the preparation method provided by the present invention; the polymer part can be dissolved into a liquid state in an aqueous solution.
[0040] It should be noted that, in the 3D printing process of the present invention, the DLP light-curing printing temperature is room temperature.
[0041] It should be noted that the experimental methods used in the present invention are all conventional methods unless otherwise specified; the reagents and materials used are all commercially available unless otherwise specified.
[0042] The acrylate-based crosslinking agent used in the following examples was prepared according to the following steps:
[0043] 0.18 mmol of hydroquinone and 0.11 mmol of dopamine hydrochloride were added to a Schlenk flask. 80 mL of dry DMF was then added under a nitrogen atmosphere to dissolve the solid powder. Once the solid was completely dissolved, 0.11 mmol of polyethylene glycol diacrylate (PEGDA575) was added dropwise to the Schlenk flask, followed by 26.4 mmol of dry triethylamine solution. The resulting mixture was stirred in an 85°C oil bath for 24 hours. After 24 hours, an additional 5.3 mmol of PEGDA575 was added under a nitrogen atmosphere to ensure sufficient acrylate end groups in the final product. After two days, the reaction was terminated, and the resulting mixture was cooled to 4°C and maintained at this temperature for at least 30 minutes. The mixture was then filtered, and the resulting yellow filtrate was precipitated in a mixture of n-hexane / ethyl acetate (1:1, v / v) and the precipitate was collected. The precipitate was collected by centrifugation, and vitamin E (12 mg) was added to the collected precipitate. The product obtained by centrifugation in the previous step was dried in a vacuum drying oven overnight to obtain a yellow viscous liquid, which is the final product, an acrylate-based crosslinker (PEG575-Do). Figure 2 As shown in Figure 2, the chemical formula for synthesizing the crosslinker PEG575-Do is simple and can be synthesized in large quantities. Figure 3 The 1H NMR spectrum of PEG575-Do is shown in FIG. The 1H NMR spectrum shows essentially no impurity peaks, confirming the successful preparation and high purity of PEG575-Do.
[0044] Example 1
[0045] A method for preparing a degradable polymer part suitable for 3D printing comprises the following steps:
[0046] Add 1% of the initiator ((2,4,6-trimethylbenzoyl) diphenylphosphine oxide) relative to the mass of PEG575-Do to PEG575-Do (1g) and shake to mix evenly to obtain a printing precursor solution. Perform photocuring printing at room temperature to obtain three-dimensional polymer sample strips. A group of sample strips with the same printing quality were placed in a 37°C aqueous solution. Sample strips were taken at 20 minutes, 2 hours, 4 hours, 6 hours, 12 hours, and 24 hours, and placed in a vacuum drying oven at room temperature overnight. The mass of the dried sample strips was then measured. At the same time, sample strips were taken at 20 minutes, 2 hours, 6 hours, and 16 hours, and their surface morphology was observed using SEM. Figure 7 shown.
[0047] Example 2
[0048] A method for preparing a degradable polymer part suitable for 3D printing comprises the following steps:
[0049] PEG575-Do (1 g) and PEG400 (0.1 g) were mixed, and an initiator ((2,4,6-trimethylbenzoyl) diphenylphosphine oxide) was added to the mixed solution at a concentration of 1% relative to the total mass of PEG575-Do and PEG400, and the mixture was shaken and mixed to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain three-dimensional polymer component specimens. A group of specimens with the same printing quality were placed in a 37°C aqueous solution, and the specimens were taken out at 2h, 4h, 6h, 12h, and 24h, respectively, and placed in a vacuum drying oven to dry overnight at room temperature, and then the mass of the dried specimens was weighed.
[0050] Example 3
[0051] A method for preparing a degradable polymer part suitable for 3D printing comprises the following steps:
[0052] PEG575-Do (0.7 g), PEG400 (0.07 g), and H2O (0.33 mL) were mixed, and an initiator (phenyl (2,4,6-trimethylbenzoyl) lithium phosphate) was added to the mixed solution at a concentration of 1% relative to the total mass of PEG575-Do and PEG400, and the mixture was shaken and mixed evenly to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain three-dimensional polymer component specimens. A group of specimens with the same printing quality were placed in a 37°C aqueous solution, and the specimens were freeze-dried at 2h, 4h, 6h, 12h, and 24h, respectively, and the mass of the freeze-dried specimens was then weighed.
[0053] Example 4
[0054] A method for preparing a degradable polymer part suitable for 3D printing comprises the following steps:
[0055] PEG575-Do (1 g), PEG400 (0.1 g), and H2O (1.65 mL) were mixed, and an initiator (phenyl (2,4,6-trimethylbenzoyl) lithium phosphate) was added to the mixed solution at a concentration of 1% relative to the total mass of PEG575-Do and PEG400, and the mixture was shaken and mixed evenly to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain three-dimensional polymer component specimens. A group of specimens with the same printing quality were placed in a 37°C aqueous solution, and the specimens were freeze-dried at 2 h, 4 h, 6 h, 12 h, and 24 h, and the mass of the freeze-dried specimens was then weighed.
[0056] Example 5
[0057] A method for preparing a degradable polymer part suitable for 3D printing comprises the following steps:
[0058] 1% of the initiator ((2,4,6-trimethylbenzoyl) diphenylphosphine oxide) relative to the mass of PEG575-Do was added to PEG575-Do (1 g) and the mixture was shaken and mixed to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain a three-dimensional structure of the polymer sample. A group of samples with the same printing quality were placed in a 37°C D2O solution, and 0.5 mL of the solution was taken at 0.5 h, 1 h, 2 h, 4 h, 8 h, 12 h, 24 h, 30 h, and 36 h. 1 H NMR was used to follow the degradation process. Figure 6 shown.
[0059] Example 6
[0060] Similar to Example 1, 1% of an initiator ((2,4,6-trimethylbenzoyl)diphenylphosphine oxide) relative to the mass of PEG575-Do was added to PEG575-Do (1 g) and the mixture was shaken and mixed to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain three-dimensional polymer component specimens. A group of specimens with the same printing quality were placed in an aqueous solution at 25°C, and the specimens were taken out at 20 minutes, 2 hours, 4 hours, 6 hours, 12 hours, and 24 hours respectively, placed in a vacuum drying oven and dried overnight at room temperature, and then the mass of the dried specimens was weighed.
[0061] Example 7
[0062] Similar to Example 1, 1% of an initiator ((2,4,6-trimethylbenzoyl)diphenylphosphine oxide) relative to the mass of PEG575-Do was added to PEG575-Do (1 g) and the mixture was shaken and mixed to obtain a printing precursor solution. Photocuring printing was performed at room temperature to obtain three-dimensional polymer component specimens. A group of specimens with the same printing quality were placed in a 50°C aqueous solution, and the specimens were taken out at 20 minutes, 2 hours, 4 hours, 6 hours, 12 hours, and 24 hours respectively. The specimens were placed in a vacuum drying oven and dried overnight at room temperature, and then the mass of the dried specimens was weighed.
[0063] It should be noted that the splines in all embodiments are selected as a group of splines with the same printing quality in order to control variables.
[0064] In order to illustrate the relevant properties of the polymer parts prepared by the present invention, the following description is made with reference to the accompanying drawings. Figures 4 to 9 .
[0065] Figure 4 This is the chemical equation for the hydrolysis of PEG575-Do. Dopamine and PEGDA575 are obtained after the hydrolysis of PEG575-Do. This indicates that the macromolecular chain of PEG575-Do breaks in an aqueous environment, and the material absorbs water, swells, and eventually hydrolyzes.
[0066] Figure 5 The polymer sample strips provided in Examples 1 to 4 were placed in a 37°C aqueous solution and the degradation curves were obtained at 0h (origin), 2h, 4h, 6h, 8h, 12h, 18h, and 24h. Figure 5 It can be seen from the degradation curves of the four splines with different ratios of monomer and solvent that the degradation rate of the material can be controlled by changing the ratio of monomer PEG400 and solvent water. From the overall trend of the degradation curve, the addition of PEG400 or the increase of water content is conducive to the rapid progress of the degradation reaction.
[0067] It should be noted that the horizontal axis of the degradation curve represents the degradation time, and the vertical axis represents the mass of the spline corresponding to each time point during degradation.
[0068] Figure 6 The polymer strip prepared in Example 5 is used 1 H NMR traces the degradation process. 1 The degradation reaction of PEG575-Do was tracked by H NMR. From the NMR spectrum during the degradation process, it can be seen that more and more dopamine and PEGDA575 were produced during the degradation of PEG575-Do.
[0069] Figure 7 The following are microstructural images of the polymer strips prepared in Example 1, captured by SEM during the degradation of PEG575-Do at 20 minutes, 2 hours, 6 hours, and 16 hours. At the beginning of degradation, the material exhibits a smooth surface. As degradation time increases, cracks, small island-like defects, or pore-like defects gradually develop on the strip surface. As degradation proceeds, surface defects become more numerous and larger, eventually leading to fracture and degradation of the entire material.
[0070] Figure 8 The polymer specimens provided in Examples 1 to 4 were placed in a 37°C aqueous solution and the degradation diagrams were obtained at 0h (Origin), 6h, 12h, 18h, and 24h. Figure 8 It can be seen that the degradation conditions of different materials of the polymer parts provided in Examples 1 to 4 are different at the same time, indicating that the degradation rate of the printed polymer parts can be controlled by controlling the ratio of monomers or the content of water solvent.
[0071] Figure 9 The following are the degradation curves of the polymer specimens provided in Examples 1, 6 and 7, which were placed in aqueous solutions at 37°C, 25°C and 50°C, at 0h (origin), 2h, 4h, 6h, 8h, 12h, 18h and 24h, respectively. Figure 9It can be seen that by changing the temperature of the aqueous solution, the degradation rate of the material can be regulated. From the overall trend of the degradation curve, the increase in temperature is conducive to the rapid progress of the degradation reaction.
[0072] The present invention describes preferred embodiments and their effects. However, those skilled in the art, once informed of the basic inventive concept, may make additional changes and modifications to these embodiments. Therefore, it is intended that the appended claims be interpreted to include the preferred embodiments as well as all changes and modifications that fall within the scope of the invention.
[0073] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.
Claims
1. A method for preparing a degradable polymer part suitable for 3D printing, characterized in that: The following steps are involved: An acrylate-based crosslinker is obtained by reacting dopamine hydrochloride with polyethylene glycol diacrylate; Mixing a monomer mixture including the cross-linking agent and a photoinitiator to form a 3D printing precursor solution, and obtaining a polymer part with a three-dimensional structure after 3D printing and curing; The three-dimensional polymer component can be dissolved in an aqueous solution into a liquid state; The monomer mixture also includes polyethylene glycol; The mass ratio of polyethylene glycol to cross-linking agent in the monomer mixture is 1:1-10; The photoinitiator accounts for 0.5-1.5% of the total mass of the monomer mixture; The photoinitiator is (2,4,6-trimethylbenzoyl)diphenylphosphine oxide or phenyl (2, 4, 6-trimethylbenzoyl) lithium phosphate; The raw materials for preparing the 3D printing precursor solution also include a water solvent; the water solvent accounts for 1% to 80% of the total mass of the monomer mixture.
2. The method for preparing a degradable polymer part suitable for 3D printing according to claim 1, characterized in that: The temperature of the aqueous solution is 25-50°C.
3. The method for preparing a degradable polymer part suitable for 3D printing according to claim 1, characterized in that: The molar ratio of dopamine hydrochloride to polyethylene glycol diacrylate is 1:0.5-1.
5.
4. A biodegradable polymer part suitable for 3D printing, characterized in that: Prepared by the preparation method according to any one of claims 1 to 3; the polymer product can be dissolved in an aqueous solution into a liquid state.