Low-ash-content 3D printing material containing photosensitive resin as well as preparation method and application of low-ash-content 3D printing material
By mixing polyurethane acrylate of polyether diol components, the oxygen content and C-O ether bond quantity are improved, and the thermal decomposition, shrinkage and thermal stability of photosensitive resins in 3D printing are solved, achieving high intensity and low strength Ash photosensitive resin improves its applicability in precision casting and high temperature applications.
Patent Information
- Application Number
- CN202411632557.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2024-12-20
AI Technical Summary
In 3D printing, existing photosensitive resins have problems such as incomplete thermal decomposition, high material shrinkage, poor thermal stability, insufficient brittleness and limited material selection, resulting in surface defects, reduced accuracy, unstable dimensions and insufficient mechanical properties of castings, which limits the Its development in precision casting and high-strength applications.
Polyurethane acrylate containing polyether diol is used as the photosensitive resin. By mixing the synthesis ratio of different polyether diol components, the oxygen content and the number of C-O ether bonds are increased, the gasification and cracking temperature is reduced, and the mechanical properties are enhanced. Applied on SLA, DLP or LCD photocuring 3D printers.
It improves the mechanical properties and low ash properties of the photosensitive resin, reduces the ash residue and linear shrinkage, and enhances its application suitability in 3D printing, especially in high-intensity and high-temperature resistance.
Smart Images
Figure CN119161542A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of 3D printing materials, and in particular to a low-ash 3D printing material containing a photosensitive resin, and a preparation method and application thereof. Background Art
[0002] 3D printing technology, also known as Additive Manufacturing (AM), is a type of rapid manufacturing technology developed in the late 1980s. Its essence is the process of stacking raw materials into corresponding physical devices by layering according to the designed 3D digital model. Compared with traditional subtractive (such as cutting, grinding, etc.) and equal material manufacturing methods, 3D printing technology can produce parts with complex structures and a wide variety of molding materials, which can greatly reduce R&D costs and reduce material waste. Thanks to the above advantages, 3D printing technology has developed rapidly in recent years, among which photocuring technology is the most widely used. Compared with other types of 3D printing technology, photocuring 3D printing technology has the advantages of high printing accuracy, high surface smoothness, and fast molding speed. It has broad application prospects in some application fields with high precision requirements such as jewelry design, hand-made figures, and cultural relics.
[0003] Rapid Casting belongs to precision casting and is a method that combines additive manufacturing technology (such as stereolithography SLA or other 3D printing technology) with investment casting (IC). Traditional lost foam for investment casting is usually made by manually carving wax, which has a long production cycle and high cost. Rapid casting uses 3D printing technology to quickly manufacture lost foam, thereby shortening some steps in traditional investment casting and speeding up production. Through 3D printing technology, complex geometric shapes can be quickly produced, design iterations can be achieved, and development time and costs can be reduced.
[0004] As the main material for precision casting and 3D printing technology, the performance of photosensitive resin must meet the requirements of precision samples for complex structures and mechanical properties. There are five problems with the photosensitive resin currently used on the market: First, incomplete thermal decomposition causes residues to remain in the mold cavity, which leads to defects on the surface of the casting, such as pores, impurities or irregular surface textures; second, the material shrinkage rate is high, resulting in reduced precision. For precision casting, especially parts with complex geometric shapes, there will be dimensional instability, resulting in product inconsistency with the design; third, poor thermal stability, softening or decomposition occurs prematurely during the casting process, resulting in mold deformation or reduced surface quality, which cannot meet the requirements of precision casting; fourth, there are problems of brittleness and insufficient mechanical properties, which are easy to be destroyed or damaged in subsequent operations, thereby affecting the integrity of the casting; fifth, limited material selection, the limited types of commercially available photosensitive resins limit the application and development of photosensitive resins in different application fields, especially in applications with special requirements (such as high strength and high temperature resistance). Summary of the invention
[0005] The purpose of the present invention is to provide a low-ash 3D printing material containing a photosensitive resin and a preparation method and application thereof to solve the above-mentioned problems.
[0006] According to one aspect of the present invention, there is provided a low-ash 3D printing material containing a photosensitive resin, wherein the photosensitive resin comprises a polyurethane acrylate containing a polyether diol, wherein the polyether diol comprises a polyethylene glycol having a molecular weight of 200 to 2000 and a polypropylene glycol having a molecular weight of 200 to 2000, wherein the molar ratio of the polyethylene glycol to the polypropylene glycol is 0 to 5:1 to 10; Wherein, the molecular structure of the polyethylene glycol is: ; The molecular structure of the polypropylene glycol is: ; Wherein, n represents the degree of polymerization of the polyether diol.
[0007] In some embodiments, the polyurethane acrylate is synthesized by reacting diisocyanate, the polyether diol and an acrylate containing active hydroxyl groups in a molar ratio of 1-7:1-3:2-10, and the general structural formula of the polyurethane acrylate is: ; Wherein, R1 is one or more of the following structural formulas: ; R2 is one or more of the following structural formulas: ; R3 is one or more of the following structural formulas: .
[0008] In some embodiments, the synthesis method of the polyurethane acrylate is: S1. Add the oligomer of the polyether diol into a three-necked flask equipped with a mechanical stirrer, evacuate at 110° C., and remove water for 0.5 to 3 h; S2, placing the product of S1 in a nitrogen atmosphere at a temperature of 50-100°C, adding 0.1%-5% by mass of stannous octoate, and adding the diisocyanate dropwise, and reacting for 2-10 hours; S3. Add 0.1% to 5% by mass of stannous octoate and the acrylate containing active hydroxyl groups to the product of S2, and react for 2 to 10 hours to obtain the polyurethane acrylate.
[0009] A method for preparing a low-ash 3D printing material containing a photosensitive resin according to any one of claims 1 to 3, comprising the following preparation method: P1, adding 20% to 80% by weight of the polyurethane acrylate, 8% to 60% by weight of the alkoxylated acrylate monomer or polyether acrylate monomer, 1% to 10% by weight of the free radical photoinitiator and 1% to 10% by weight of the auxiliary agent into a reactor; P2, mechanically stir and mix evenly, the speed is 800~1500 r / min, stir for 0.5~1 h, then vacuum and remove bubbles for 10~30 min; P3. Fill and seal the product.
[0010] In some embodiments, the alkoxylated acrylate monomer is at least one of propoxylated neopentyl glycol diacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and ethoxylated pentaerythritol tetraacrylate.
[0011] In some embodiments, the polyether acrylate monomer is at least one of ethoxyethoxyethyl acrylate, ethylene glycol dimethacrylate, polyethylene glycol monomaleate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, and dipropylene glycol dimethacrylate.
[0012] In some embodiments, the free radical photoinitiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, and ethyl 2,4,6-trimethylbenzoylphenylphosphonate.
[0013] In some embodiments, the auxiliary agent includes at least one of an inhibitor, a defoamer, a leveling agent, and an organic pigment.
[0014] An application of a low-ash 3D printing material containing a photosensitive resin comprises applying the low-ash 3D printing material containing the photosensitive resin to a SLA, DLP or LCD light-curing 3D printer with a curing wavelength of 380-420 nm.
[0015] Compared with the prior art, the beneficial effects of this application are: The present application improves the mechanical properties of the polyurethane acrylate oligomer by adjusting the synthesis ratio of different polyether diol components while ensuring a high oxygen content and a large number of CO ether bonds; the high oxygen content and the large number of CO ether bonds ensure that the prepared polyurethane acrylate oligomer has a low gasification and cracking temperature, is easy to burn, and reduces the ash residual rate; the synthesis ratio of different polyether diol components is matched, so that it has excellent mechanical properties and low linear shrinkage. BRIEF DESCRIPTION OF THE DRAWINGS
[0016] Figure 1 It is a schematic diagram of the synthesis process of the present invention; Figure 2 is the infrared spectrum of the prepared polyurethane acrylate. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0018] refer to Figures 1 to 2 , the present application provides a low-ash 3D printing material containing a photosensitive resin, wherein the photosensitive resin includes a polyurethane acrylate containing a polyether diol, wherein the polyether diol includes a polyethylene glycol with a molecular weight of 200 to 2000 and a polypropylene glycol with a molecular weight of 200 to 2000, wherein the molar ratio of the polyethylene glycol to the polypropylene glycol is 0 to 5:1 to 10; Wherein, the molecular structure of the polyethylene glycol is: ; The molecular structure of the polypropylene glycol is: ; Wherein, n represents the degree of polymerization of the polyether diol.
[0019] The polyurethane acrylate is synthesized by reacting diisocyanate, the polyether diol and an acrylate containing active hydroxyl groups in a molar ratio of 1-7:1-3:2-10. The general structural formula of the polyurethane acrylate is: ; Wherein, R1 is one or more of the following structural formulas: ; R2 is one or more of the following structural formulas: ; R3 is one or more of the following structural formulas: .
[0020] The synthesis method of the polyurethane acrylate is: S1. Add the oligomer of the polyether diol into a three-necked flask equipped with a mechanical stirrer, evacuate at 110° C., and remove water for 0.5 to 3 h; S2, placing the product of S1 in a nitrogen atmosphere at a temperature of 50-100°C, adding 0.1%-5% by mass of stannous octoate, and adding the diisocyanate dropwise, and reacting for 2-10 hours; S3. Add 0.1% to 5% by mass of stannous octoate and the acrylate containing active hydroxyl groups to the product of S2, and react for 2 to 10 hours to obtain the polyurethane acrylate.
[0021] The prepared polyurethane acrylate was characterized by Fourier transform infrared spectrometer. Figure 2 As shown, located at 2200~2280cm -1 The N=C=O stretching vibration peak in the wavenumber range disappeared, indicating that the acrylate group completely blocked the isocyanate and the target polyurethane acrylate was successfully prepared. In addition, the 3315cm -1 、1723cm -1 and are the NH and C=O stretching vibration peaks on the formed carbamate bond, 1021 cm -1 The strongest peak is the stretching vibration peak of the COC ether bond which exists in large quantities in the prepared polyurethane acrylate, ensuring a lower gasification and cracking temperature.
[0022] A method for preparing a low-ash 3D printing material containing a photosensitive resin, comprising the following preparation methods: P1, adding 20% to 80% by weight of the polyurethane acrylate, 8% to 60% by weight of the alkoxylated acrylate monomer or polyether acrylate monomer, 1% to 10% by weight of the free radical photoinitiator and 1% to 10% by weight of the auxiliary agent into a reactor; P2, mechanically stir and mix evenly, the speed is 800~1500 r / min, stir for 0.5~1 h, then vacuum and remove bubbles for 10~30 min; P3. Fill and seal the product.
[0023] The alkoxylated acrylate monomer is at least one of propoxylated neopentyl glycol diacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and ethoxylated pentaerythritol tetraacrylate.
[0024] The polyether acrylate monomer is at least one of ethoxyethoxyethyl acrylate, ethylene glycol dimethacrylate, polyethylene glycol monomaleate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, and dipropylene glycol dimethacrylate.
[0025] The free radical photoinitiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide and ethyl 2,4,6-trimethylbenzoylphenylphosphonate.
[0026] The auxiliary agent includes at least one of an inhibitor, a defoamer, a leveling agent, and an organic pigment.
[0027] The application of low-ash 3D printing materials containing photosensitive resins includes the application of low-ash 3D printing materials containing photosensitive resins on SLA, DLP or LCD light-curing 3D printers with a curing wavelength of 380~420nm.
[0028] The present application improves the mechanical properties of the polyurethane acrylate oligomer by adjusting the synthesis ratio of different polyether diol components while ensuring a high oxygen content and a large number of CO ether bonds; the high oxygen content and the large number of CO ether bonds ensure that the prepared polyurethane acrylate oligomer has a low gasification and cracking temperature, is easy to burn, and reduces the ash residual rate; the synthesis ratio of different polyether diol components is matched, so that it has excellent mechanical properties and low linear shrinkage.
[0029] Example 1: In this example, a polyurethane acrylate oligomer was synthesized, named resin 3, and a low-ash 3D printing material containing a photosensitive resin was prepared based on the oligomer; The synthetic process of resin 3 is as follows Figure 1 The formula ratio is shown in Table 1, and the specific synthesis steps are as follows: 480 g of 800 molecular weight polyethylene glycol and 800 g of 2000 molecular weight polypropylene glycol were added to a three-necked flask equipped with a mechanical stirrer, and the mixture was vacuumed at 110°C to remove water for 0.5-1 h. Place the mixture under nitrogen atmosphere at 50°C, add 0.15% by weight of stannous octoate, and then dropwise add 445 parts by weight of diisocyanate, and react for 5 hours; Add 1.5% by weight of stannous octoate and 348 g by weight of polyethylene glycol monomaleate, and react for 7 h; 50 g of the synthesized polyurethane acrylate, 20 g of ethoxylated trimethylolpropane triacrylate, 30 g of diethylene glycol dimethacrylate, 2% by weight of a photoinitiator, and 1% by weight of an auxiliary agent were added into a reaction kettle; Mechanically stir and mix evenly at a speed of 800-1500 r / min. Stir for 0.5 h and then evacuate and remove bubbles for 15 min. Fill and seal the product.
[0030] Example 2: In this example, a polyurethane acrylate oligomer was synthesized, named Resin 1, and a low-ash 3D printing material containing a photosensitive resin was prepared based on it. The difference between this example and Example 1 is that the reaction temperature is 60°C, the reaction time is 8 hours, the diol molecular weight and the amount of catalyst used, and the polyether diol used is 800g by weight of polyethylene glycol and 200g by weight of polypropylene glycol. The other reaction conditions are the same, and the reaction raw material formula design is shown in Table 1.
[0031] Example 3: In this example, a polyurethane acrylate oligomer was synthesized, named as resin 2, and a low-ash 3D printing material containing a photosensitive resin was prepared based on it. The difference between this example and Example 1 is that the reaction temperature is 80°C, the reaction time is 6 h, the diol molecular weight and the amount of catalyst used, and the polyether diol used is 640g by weight of polyethylene glycol and 400g by weight of polypropylene glycol. The other reaction conditions are the same, and the reaction raw material formula design is shown in Table 1.
[0032] Example 4: In this example, a polyurethane acrylate oligomer was synthesized, named as resin 4, and a low-ash 3D printing material containing a photosensitive resin was prepared based on the synthesized polyurethane acrylate oligomer. The difference between this example and Example 1 is that the reaction temperature is 100°C, the reaction time is 3 h, the diol molecular weight and the amount of catalyst used, and the polyether diol used is 320g by weight of polyethylene glycol and 1200g by weight of polypropylene glycol. The other reaction conditions are the same, and the reaction raw material formula design is shown in Table 1.
[0033] Example 5: In this example, a polyurethane acrylate oligomer was synthesized, named Resin 5, and a low-ash 3D printing material containing a photosensitive resin was prepared based on it. The difference between this example and Example 1 is that the reaction temperature is 75°C, the reaction time is 5 h, the diol molecular weight and the amount of catalyst used, and the polyether diol used is 160g by weight of polyethylene glycol and 1600g by weight of polypropylene glycol. The other reaction conditions are the same, and the reaction raw material formula design is shown in Table 1.
[0034] Example 6: In this example, a polyurethane acrylate oligomer was synthesized, named as resin 6, and a low-ash 3D printing material containing a photosensitive resin was prepared based on it. The difference between this example and Example 1 is that the reaction temperature is 85°C, the reaction time is 6h, the diol molecular weight and the amount of catalyst used, and the polyether diol used is 2000g of polypropylene glycol by weight. The other conditions are the same, and the reaction raw material formula design is shown in Table 1.
[0035] Table 1 Proportions of the synthetic components of polyurethane acrylate oligomers in various examples Comparative Example 1: The difference between this comparative example and Example 1 is that the acrylate monomer is 50 g by weight of diethylene glycol dimethacrylate, and the other conditions are the same. The formula table is shown in Table 2.
[0036] Comparative Example 2: This comparative example differs from Example 1 in that the acrylate monomer is 50 g by weight of ethoxylated trimethylolpropane triacrylate, and other conditions are the same. The formula is shown in Table 2.
[0037] Comparative Example 3: The difference between this comparative example and Example 1 is that the acrylate monomer is 30 g by weight of 1,6-hexanediol diacrylate and 20 g by weight of trimethylolpropane triacrylate, and other conditions are the same. The formula is shown in Table 2.
[0038] Comparative Example 4: The difference between this comparative example and Example 1 is that the oligomer is a commercial product, and the other conditions are the same. The formula table is shown in Table 2.
[0039] Comparative Example 5: The difference between this comparative example and Example 1 is that the oligomer is a commercial product, and the other conditions are the same. The formula table is shown in Table 2.
[0040] Table 2 Composition ratio of each comparative example Ash content testing method: The above-mentioned Examples 1-6 and Comparative Examples 1-5 were printed on a light-curing 3D printer using SLA, DLP or LCD and a curing wavelength of 380-420 nm, and then the mold was made with gypsum slurry. Finally, it was placed in a muffle furnace for high-temperature combustion to test the residual ash content. The test results are shown in Table 3.
[0041] Table 3 Performance characteristics of prepared samples and comparative samples Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A low-ash 3D printing material containing photosensitive resin, It is characterized in that The photosensitive resin includes polyurethane acrylate containing polyether diol, wherein the polyether diol includes polyethylene glycol with a molecular weight of 200-2000 and polypropylene glycol with a molecular weight of 200-2000, wherein the molar ratio of the polyethylene glycol to the polypropylene glycol is 0-5:1-10; Wherein, the molecular structure of the polyethylene glycol is: ; The molecular structure of the polypropylene glycol is: ; Wherein, n represents the degree of polymerization of the polyether diol.
2. The low-ash 3D printing material containing photosensitive resin according to claim 1, It is characterized in that The polyurethane acrylate is synthesized by reacting diisocyanate, the polyether diol and an acrylate containing active hydroxyl groups in a molar ratio of 1-7:1-3:2-10. The general structural formula of the polyurethane acrylate is: ； Wherein, R1 is one or more of the following structural formulas: ； R2 is one or more of the following structural formulas: ； R3 is one or more of the following structural formulas: 。 3. The low-ash 3D printing material containing photosensitive resin according to claim 2, It is characterized in that The synthesis method of the polyurethane acrylate is: S1. Add the oligomer of the polyether diol into a three-necked flask equipped with a mechanical stirrer, evacuate at 110° C., and remove water for 0.5 to 3 h; S2, placing the product of S1 in a nitrogen atmosphere at a temperature of 50-100°C, adding 0.1%-5% by mass of stannous octoate, and adding the diisocyanate dropwise, and reacting for 2-10 hours; S3. Add 0.1% to 5% by mass of stannous octoate and the acrylate containing active hydroxyl groups to the product of S2, and react for 2 to 10 hours to obtain the polyurethane acrylate.
4. A method for preparing a low-ash 3D printing material containing a photosensitive resin according to any one of claims 1 to 3, It is characterized in that The invention comprises the following preparation methods: P1, adding 20% to 80% by weight of the polyurethane acrylate, 8% to 60% by weight of the alkoxylated acrylate monomer or polyether acrylate monomer, 1% to 10% by weight of the free radical photoinitiator and 1% to 10% by weight of the auxiliary agent into a reactor; P2, mechanically stir and mix evenly, the speed is 800~1500 r / min, stir for 0.5~1 h, then vacuum and remove bubbles for 10~30 min; P3. Fill and seal the product.
5. The method for preparing a low-ash 3D printing material containing a photosensitive resin according to claim 4, It is characterized in that The alkoxylated acrylate monomer is at least one of propoxylated neopentyl glycol diacrylate, propoxylated glycerol triacrylate, ethoxylated trimethylolpropane triacrylate, and ethoxylated pentaerythritol tetraacrylate.
6. The method for preparing a low-ash 3D printing material containing a photosensitive resin according to claim 4, It is characterized in that The polyether acrylate monomer is at least one of ethoxyethoxyethyl acrylate, ethylene glycol dimethacrylate, polyethylene glycol monomaleate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, and dipropylene glycol dimethacrylate.
7. The method for preparing a low-ash 3D printing material containing a photosensitive resin according to claim 4, It is characterized in that The free radical photoinitiator is at least one of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide and ethyl 2,4,6-trimethylbenzoylphenylphosphonate.
8. The method for preparing a low-ash 3D printing material containing a photosensitive resin according to claim 4, It is characterized in that The auxiliary agent includes at least one of an inhibitor, a defoamer, a leveling agent, and an organic pigment.
9. Application of a low-ash 3D printing material containing photosensitive resin, It is characterized in that The low-ash 3D printing material containing a photosensitive resin according to any one of claims 1 to 8 is used on a SLA, DLP or LCD light-curing 3D printer with a curing wavelength of 380 to 420 nm.