Method for preparing high-precision 3D printing starch-based ink through cooperation of critical melting and polysaccharide

Abstract

The invention discloses a method for preparing high-precision 3D printing starch-based ink through cooperation of critical melting and polysaccharide. The preparation method comprises the following steps: slowly adding galactomannan into distilled water, stirring at 45-80 DEG C for 30-60 minutes to completely dissolve galactomannan, and cooling to room temperature; adding starch, and uniformly stirring at room temperature; and heating and stirring the obtained product at a starch critical gelatinization temperature TO for 30-45 minutes to obtain starch-based ink suitable for high-precision 3D printing, then putting the starch-based ink into a 3D printing injector, naturally cooling, removing bubbles, adjusting printing parameters, and then printing to obtain a high-precision starch-based 3D printing product. The starch is used as a raw material, the galactomannan is used as an auxiliary material, the precision of a starch-based 3D printing product is greatly improved by adopting a physical means, the condition is safe, green and mild, the product is endowed with functionality, and personalized requirements are met.

Description

Technical Field

[0001] The invention relates to the technical field of green printing materials, and in particular to a method for preparing a highly printable starch-based 3D printing ink by utilizing critical melting synergistic polysaccharides to improve precision. Background Art

[0002] With the rapid development of 3D printing technology, printing accuracy directly affects the performance and application effect of the final product. Traditional 3D printing materials are mostly plastics, metals, etc. However, these materials have problems such as high cost and great environmental impact in certain application scenarios. Therefore, the development of new environmentally friendly materials has become one of the research hotspots. Starch, as a natural polymer material, has good moldability and biodegradability and is suitable for 3D printing. However, natural starch-based inks have problems such as difficulty in extrusion, poor molding effect, and poor stability. Therefore, it is particularly important to select suitable additives to improve their fluidity and printing accuracy.

[0003] Chinese invention patent application CN117297074A discloses a method for preparing 3D printing materials based on cassava starch, firstly, a cassava starch suspension is obtained by high-pressure micro-jetting, then protein, fatty acid and polysaccharide are added and stirred evenly, ultrasonic treatment is performed to obtain a pre-treated material, and the pre-treated material is heated to make the starch completely gelatinized and then loaded into the 3D printer material barrel, and 3D printing is performed after the gel is cooled. Although this technology greatly improves the printing accuracy, the preparation of materials through high-pressure micro-jetting, ultrasound and complete gelatinization treatment has the disadvantages of cumbersome operation and energy consumption. At the same time, the protein is prone to denaturation phenomena such as structural destruction, causing allergies, and is not suitable for some people.

[0004] Chinese invention patent application CN117106337A discloses a method for preparing a starch-based 3D printing ink suitable for high printability, wherein corn starch is first dissolved in dimethyl sulfoxide and heated until completely gelatinized, and methacrylic anhydride and triethylamine are added; then precipitated in anhydrous ethanol, washed with deionized water, and freeze-dried to obtain methacrylated starch; methacrylated starch, high-amylose corn starch, and ordinary starch are gelatinized and mixed evenly in proportion to obtain starch-based ink. This technology completely gelatinizes starch and then adds chemical reagents for cross-linking. Although the gel strength is improved, it has the disadvantages of energy consumption and safety risks and is not suitable for widespread use. Therefore, the energy-saving and green method used in the present invention to prepare printing ink will better meet market demand. Summary of the invention

[0005] The primary purpose of the present invention is to provide a method for preparing a starch-based 3D printing ink raw material that can utilize critical melting synergistic polysaccharides to improve the accuracy of 3D printed products, and give the products functionality to meet personalized needs.

[0006] The purpose of the present invention is achieved through the following technical solutions:

[0007] The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide comprises the following steps:

[0008] 1) Add galactomannan into distilled water, heat and stir until completely dissolved, and cool to room temperature;

[0009] 2) adding starch and stirring evenly at room temperature; the amount of galactomannan is 0.5-2% of the dry weight of starch;

[0010] 3) the product obtained in step 2) is subjected to the critical gelatinization temperature T O The mixture is heated and stirred for 30 to 45 minutes, and high-precision 3D printing starch-based ink is obtained after melting.

[0011] To further achieve the purpose of the present invention, preferably, the galactomannan is one or more of locust bean gum, tara gum and guar gum.

[0012] Preferably, in step 1), the heating temperature is 45-80°C.

[0013] Preferably, in step 1), the stirring speed is 400-600 rpm, and the stirring time is 30-60 min.

[0014] Preferably, in step 1), the amount of distilled water added is 4 to 5 times the mass of the dry basis of starch.

[0015] Preferably, in step 2), the uniform stirring is performed by magnetic stirring at a rotation speed of 400 to 600 rpm for 20 to 40 minutes.

[0016] Preferably, in step 2), the starch is one or more of taro starch, potato starch and tapioca starch.

[0017] Preferably, in step 3), the critical gelatinization temperature of starch is O Obtained by DSC measurement; the stirring speed is 400-600 rpm.

[0018] Preferably, the high-precision 3D printing starch-based ink obtained in step 3) is placed in a 3D printing syringe, cooled naturally, bubbles are removed, and printing is performed after adjusting the printing parameters to obtain a high-precision starch-based 3D printed product.

[0019] Preferably, the printing temperature in the printing parameters is set to the critical gelatinization temperature of starch T O , nozzle diameter is 0.6~1mm, and printing speed is 25~45mm / s.

[0020] The product obtained by the invention is a 3D printed white solid product without odor, and the 3D printing accuracy reaches more than 95%.

[0021] The raw material used in the present invention is starch, including various commercial starches such as yam starch, potato starch, cassava starch, etc. The galactomannan in the raw material is a common food additive on the market.

[0022] Compared with the prior art, the present invention has the following advantages:

[0023] 1) The raw materials used in the present invention are natural starch and common food additives, which are safe and non-toxic, have been widely used in food processing and production, have low production costs, and have broad application prospects in the field of 3D printing.

[0024] 2) Compared with the technology of preparing starch-based ink by heating above the gelatinization temperature, the present invention uses the starch critical gelatinization temperature T with low energy consumption. O As the heating temperature, the amylose leached during gelatinization is likely to form more three-dimensional gel network structures, which enhances the viscoelasticity of the gel and increases the viscosity of the gel. O There are also more crystal structures, which significantly improve the gel hardness and form a starch gel with high stability and high gel strength.

[0025] 3) The functional properties of the product obtained by the present invention are easy to control. By adjusting the amount of galactomannan added, products with different textures, rheological properties or 3D printing precision can be obtained to meet different needs.

[0026] 4) The invention has the characteristics of high efficiency, high printability, low cost, etc., and no toxic or polluting raw materials are used in the preparation process, the conditions are mild, and the product is green and safe. The addition of galactomannan gives the product functionality.

[0027] 5) The technology of the present invention is simple and can be easily automated. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 The starch gel without and with galactomannan added in Comparative Example 1, Comparative Example 2, and Examples 1-3 at T O and water holding capacity diagrams for treatments above gelatinization temperature.

[0029] Figure 2 The starch gel without and with galactomannan added in Comparative Example 1, Comparative Example 2, and Examples 1-3 at T O Apparent viscosity diagram for treatments above and pasting temperatures.

[0030] Figure 3 The starch gel without and with galactomannan added in Comparative Example 1, Comparative Example 2, and Examples 1-3 at T O Rheological diagrams of treatments above the gelatinization temperature.

[0031] Figure 4 The starch gel without and with galactomannan added in Comparative Example 1, Comparative Example 2, and Examples 1-3 at T O Figure 3D printed products processed above the gelatinization temperature. DETAILED DESCRIPTION

[0032] In order to better understand the present invention, the present invention is further described below in conjunction with embodiments, but the embodiments of the present invention are not limited thereto.

[0033] Extrusion printing is the most common 3D printing method, which is divided into cold printing and hot printing. Cold printing is to heat the starch material to a gelatinized state, then cool it down to make it regenerate, and then reheat it to the printing temperature, and finally stack it layer by layer through an extruder to form a 3D printed object. Hot printing is to heat the starch material to a gelatinized state and stack it directly through an extruder at high temperature. At present, starch-based inks are often prepared by heating above the gelatinization temperature, which consumes a lot of energy. If additives are added, it may cause degradation, and the printed products have disadvantages such as low precision and poor self-support.

[0034] Critical melting treatment is a "clean label" physical treatment method proposed in recent years, which takes the critical temperature at which the ordered starch crystals begin to transform into disorder as the core of regulation. O , T P , T C These correspond to the temperatures at which starch crystals begin to melt, most starch crystals melt, and all starch crystals melt. Treatment at these three temperatures will cause changes in the internal structure of starch, thereby affecting the physical and chemical properties of starch. This method consumes less energy than the method of heating above the gelatinization temperature and produces a better gel.

[0035] Galactomannan is a natural polysaccharide, mainly composed of two monosaccharides, galactose and mannose, and widely found in plants. It has good biocompatibility and solubility, and is often used in food, medicine, cosmetics and other fields. Galactomannan has excellent thickening, stabilization and gelling properties, so it has important application value in improving the performance of natural printing inks and enhancing product quality.

[0036] The present invention can significantly improve the gel properties and 3D printing properties of the composite starch gel by treating starch with galactomannan in a critical melting synergistic manner. ODuring critical melting treatment, starch granules swell and may show a pore structure. These pores will enhance the ability of starch granules to bind water molecules. At the same time, the leached amylose easily forms a three-dimensional gel network structure, or entangles with the remaining crystal structure, making the starch structure more compact and stable, thereby enhancing the gel properties. Different galactomannans contain different proportions of galactose and mannose. The difference in molecular structure makes the effect between them and starch different, but they can all enhance the gel properties. Galactomannans contain a large number of free hydroxyl groups, which can better bind water molecules and significantly improve the water holding capacity of the gel. At the same time, the galactose side chain interacts with the surrounding water molecules or the exuded amylose, resulting in intermolecular chain entanglement and increased viscosity, so that the starch gel can be smoothly extruded from the nozzle and the surface of the printed product becomes smooth. The addition of galactomannan will also enhance the hydrogen bonding force of the gel, fill its three-dimensional spatial network structure to a certain extent, thereby playing a reinforcing role, so that the printed product has good formability and self-support; therefore, the present invention utilizes critical melting to synergize galactomannan to treat starch to develop a starch-based ink suitable for cooling printing, with low energy consumption, high precision and strong self-support.

[0037] The raw material used in the present invention is starch, including various commercial starches such as yam starch, potato starch, cassava starch, etc. The galactomannan in the raw material is a common food additive on the market.

[0038] The galactomannan used in the present invention is purchased from Macklin Company and Yuanye Company.

[0039] Testing methods for the physical and chemical properties and 3D printing properties of the composite gel in the embodiments of the present invention:

[0040] Determination of water holding capacity of starch-based ink: The water holding capacity of starch gel was determined by centrifugal weighing method. After the cooled starch gel was centrifuged (4000rpm, 4℃, 20min), the water was removed to determine the water holding capacity. The calculation formula is as follows:

[0041]

[0042] Where: m0 is the mass of the centrifuge tube, g; m1 is the total mass of the centrifuge tube and gel after removing water, g; m2 is the total mass of the centrifuge tube and gel before centrifugation, g.

[0043] Determination of rheological properties: Anton Paar rheometer (MCR 702e MultiDrive, AT) was used to measure the rheological properties of the samples in the linear viscoelastic region. -1 ~200s -1The apparent viscosity was measured in the range of 1-100 rad / s. The storage modulus (G') and loss modulus (G") were measured in the range of angular frequency and strain of 2%. The temperature was 25°C.

[0044] Determination of texture properties: The P / 0.5R probe in the TA-XT 2i texture analyzer was used to measure the elasticity, cohesion, adhesiveness, chewiness and 40% compression hardness of the samples.

[0045] Determination of the accuracy and stability of printed samples: Use a ruler to measure the side length and height of the printed sample, compare it with the side length and height of the model and calculate the deviation. The accuracy is expressed by the deviation at 0 hours after printing, and the stability is expressed by the deviation after printing and placing it in a 4℃ refrigerator for 2, 4, 6, and 24 hours. The calculation formula is as follows:

[0046]

[0047]

[0048]

[0049] Where: E l and E h are the relative deviations of side length and height, %; S l and S h are the side length and height of the printed sample, mm; T l and T h are the design values ​​of the side length and height of the model, mm; E a The average value of the relative deviations of side length and height is the accuracy, %.

[0050] Example 1

[0051] (1) slowly adding 0.5% locust bean gum based on the dry weight of canna starch into distilled water 5 times the dry weight of the starch, stirring with a magnetic stirrer at 400 rpm at 80° C. for 30 min to completely dissolve the locust bean gum, and cooling to room temperature;

[0052] (2) adding starch to the product obtained in step (1), and stirring at 400 rpm for 30 min at room temperature;

[0053] (3) heating and stirring the product obtained in step (2) at 61° C. and 400 rpm for 40 min to obtain a high-precision 3D printing starch-based ink;

[0054] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 1 mm, the printing speed was controlled to 30 mm / s, and the printing temperature was 61° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0055] Example 2

[0056] (1) slowly adding 1% of tara gum based on the dry weight of potato starch into distilled water based on the dry weight of starch by 4.8 times, stirring with a magnetic stirrer at 500 rpm for 40 min at 45° C. to completely dissolve the tara gum, and cooling to room temperature;

[0057] (2) adding starch to the product obtained in step (1), and stirring at 500 rpm for 20 min at room temperature;

[0058] (3) heating and stirring the product obtained in step (2) at 65° C. and 500 rpm for 30 min to obtain a high-precision 3D printing starch-based ink;

[0059] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 0.8 mm, the printing speed was controlled to 35 mm / s, and the printing temperature was 65° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0060] Example 3

[0061] (1) slowly adding 1.5% guar gum by weight of cassava starch to distilled water 4.6 times by weight of the starch by weight, stirring with a magnetic stirrer at 600 rpm for 50 min at 60° C. to completely dissolve the guar gum, and cooling to room temperature;

[0062] (2) adding starch to the product obtained in step (1), and stirring at 600 rpm for 40 min at room temperature;

[0063] (3) heating and stirring the product obtained in step (2) at 59° C. and 600 rpm for 45 min to obtain a high-precision 3D printing starch-based ink;

[0064] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 0.6 mm, the printing speed was controlled to 40 mm / s, and the printing temperature was 59° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0065] Example 4

[0066] (1) slowly adding 1.5% tara gum based on the dry weight of canna starch into distilled water based on 4.4 times the dry weight of the starch, stirring with a magnetic stirrer at 400 rpm for 60 min at 45° C. to completely dissolve the locust bean gum, and then cooling to room temperature;

[0067] (2) adding starch to the product obtained in step (1), and stirring at 400 rpm for 25 min at room temperature;

[0068] (3) heating and stirring the product obtained in step (2) at 61° C. and 400 rpm for 30 min to obtain a high-precision 3D printing starch-based ink;

[0069] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 0.8 mm, the printing speed was controlled to 25 mm / s, and the printing temperature was 61° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0070] Example 5

[0071] (1) 0.5% guar gum by weight of potato starch on a dry basis was slowly added to distilled water 4.2 times the weight of the starch on a dry basis, and magnetic stirring was performed at 500 rpm at 60° C. for 40 min to completely dissolve the tara gum, and then the mixture was cooled to room temperature;

[0072] (2) adding starch to the product obtained in step (1), and stirring at 500 rpm for 35 min at room temperature;

[0073] (3) heating and stirring the product obtained in step (2) at 65° C. and 500 rpm for 40 min to obtain a high-precision 3D printing starch-based ink;

[0074] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 1 mm, the printing speed was controlled to 45 mm / s, and the printing temperature was 65° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0075] Example 6

[0076] (1) slowly adding 2% locust bean gum based on the dry weight of cassava starch into distilled water based on 4 times the dry weight of the starch, stirring with a magnetic stirrer at 600 rpm at 80° C. for 50 min to completely dissolve the guar gum, and cooling to room temperature;

[0077] (2) adding starch to the product obtained in step (1), and stirring at 400 rpm for 40 min at room temperature;

[0078] (3) heating and stirring the product obtained in step (2) at 59° C. and 600 rpm for 35 min to obtain a high-precision 3D printing starch-based ink;

[0079] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 0.6 mm, the printing speed was controlled to 35 mm / s, and the printing temperature was 59° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0080] Comparative Example 1

[0081] (1) Prepare distilled water 5 times the dry weight of starch without adding galactomannan;

[0082] (2) adding taro starch to the distilled water in step (1), and stirring at 500 rpm for 40 min at room temperature;

[0083] (3) heating and stirring the product obtained in step (2) at 61° C. and 500 rpm for 40 min to obtain a 3D printing starch-based ink;

[0084] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 1 mm, the printing speed was controlled to 30 mm / s, and the printing temperature was 61° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0085] Comparative Example 2

[0086] (1) slowly adding 0.5% locust bean gum based on the dry weight of canna starch into distilled water 5 times the dry weight of the starch, stirring with a magnetic stirrer at 600 rpm at 80° C. for 40 min to completely dissolve the locust bean gum, and cooling to room temperature;

[0087] (2) adding starch to the product obtained in step (1), and stirring at 600 rpm for 35 min at room temperature;

[0088] (3) heating and stirring the product obtained in step (2) at 90° C. and 600 rpm for 30 min to obtain a 3D printing starch-based ink;

[0089] (4) The ink obtained in step (3) was placed in a 3D printing syringe, and bubbles were removed. The nozzle diameter was set to 1 mm, the printing speed was controlled to 30 mm / s, and the printing temperature was 70° C. The 3D printed model was a three-dimensional box of 30.84 mm×30.84 mm×15.42 mm (length×width×height).

[0090] Comparative Example 1: Using the original canna starch without adding galactomannan as raw material, at the critical gelatinization temperature TO In comparative example 2, canna starch with galactomannan added was used as raw material to prepare starch gel at a temperature higher than the gelatinization temperature, and 3D printing was performed.

[0091] (I) Physical and chemical properties of composite starch gel

[0092] The water holding capacity of the starch gels of Comparative Example 1, Comparative Example 2, and Examples 1-3 is as follows: Figure 1 , the apparent viscosity is Figure 2 , rheological properties such as Figure 3 , the texture properties are shown in Table 1. It can be found that the water holding capacity of Comparative Example 1 (native starch gel) is 83.83%, the water holding capacity of Comparative Example 2 (composite starch gel heated above the gelatinization temperature) is 71.92%, and the water holding capacity of Examples 1-3 (composite starch gel) is 98.90%, 98.53%, and 94.10%, which indicates that critical melting synergistic galactomannan treatment can significantly improve the water holding performance of the gel, thereby affecting the gel strength.

[0093] The apparent viscosity of the composite starch gel of Examples 1-3 is lower than that of the starch gel of Comparative Examples 1 and 2, indicating that critical melting and galactomannan have a protective effect on starch granules, can encapsulate or inhibit the crushing, swelling and dissolution of amylose molecules of granules, so the viscosity is reduced relative to the original starch gel. In addition, the storage modulus G' of the composite starch gel of the embodiment is up to 2303Pa, slightly lower than the original starch gel, but much higher than 542Pa of Comparative Example 2. As can be seen from Table 1, critical melting and galactomannan significantly improve the texture characteristics of starch gel, and the hardness can reach up to 461.04g, which is about twice that of Comparative Example 2, and the other parameters are also correspondingly improved. This shows that critical melting and galactomannan have a significant enhancing effect on the gel strength characteristics of starch gel, and can be used to prepare functional 3D printed products that meet personalized needs.

[0094] Table 1 Measurement results of texture properties of comparative examples and examples

[0095]

[0096] (II) 3D printing properties of composite starch gel

[0097] 3D printed products of the composite starch gels added with galactomannan in Examples 1-3, the native starch gel without polysaccharide added in Comparative Example 1, and the composite starch gels prepared by heating to above the gelatinization temperature in Comparative Example 2 are as follows: Figure 4As shown. It can be found that comparative example 1, that is, a single canna starch gel, can be 3D printed, but the surface of the printed product is rough, and there is a phenomenon of unevenness and unevenness; comparative example 2, that is, the composite starch gel prepared by heating to 90°C, has poor formability and rough surface after printing. In Examples 1-3, the composite starch gels with a certain concentration of galactomannan added significantly improved the apparent morphology and formability after printing, and have the potential to prepare high-precision 3D printed products. From the results in Table 2, it can be seen that the accuracy deviation of comparative example 1 is 3.60%, the stability deviation of 24h is 26.29%, the accuracy deviation of comparative example 2 is 14.40%, and the stability deviation of 24h is 42.23%, which shows that critical melting treatment, that is, heating at the initial gelatinization temperature, can significantly improve the accuracy and stability of 3D printed products. However, the highest accuracy deviation of Examples 1-3 is only 2.63%, which is much lower than 14.4% of Comparative Example 2; in terms of stability deviation, 2h-24h, Examples 1-3 are also much better than Comparative Examples 1 and 2. It can be seen that the accuracy and stability deviations of Examples 1-3 are significantly smaller than those of Comparative Examples 1 and 2, which indicates that the critical melting synergistic galactomannan treatment after the addition of galactomannan can achieve accuracy and stability of the 3D printed products with obvious advantages.

[0098] Table 2 Measurement results of accuracy and stability deviation of 3D printed samples of comparative examples and examples

[0099]

[0100] Comparison between the above embodiments and the comparative examples shows that the present invention has a critical gelatinization temperature T O The material is heated to open the starch chain appropriately to interact with galactomannan, avoiding the problems of energy consumption and adding chemical cross-linking agents, which is beneficial to increase the thermal stability and gel properties of the material. Therefore, the method of using critical melting synergistic polysaccharides to treat starch-based materials and perform 3D printing is more likely to prepare 3D printed products that can be used in food industry production and have good stability. The present invention improves the thermal stability and gel properties of starch by stirring and compounding starch and galactomannan at the initial gelatinization temperature, and promotes the formation of the gel network by hydrogen bond interaction. There is no need to add other chemical cross-linking agents for complete gelatinization. The method is energy-saving, safe and efficient.

[0101] The embodiments and comparative examples described above provide detailed descriptions of the technical solutions and gain effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide, characterized in that The following steps are involved: 1) Add galactomannan into distilled water, heat and stir until completely dissolved, and cool to room temperature; 2) adding starch and stirring evenly at room temperature; the amount of galactomannan is 0.5-2% of the dry weight of starch; 3) the product obtained in step 2) is subjected to the critical gelatinization temperature T O The mixture is heated and stirred for 30 to 45 minutes, and high-precision 3D printing starch-based ink is obtained after melting.

2. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: The galactomannan is one or more of locust bean gum, tara gum and guar gum.

3. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 1), the heating temperature is 45-80°C.

4. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 1), the stirring speed is 400-600 rpm, and the stirring time is 30-60 min.

5. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 1), the amount of distilled water added is 4 to 5 times the mass of the dry basis of starch.

6. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 2), the uniform stirring is performed by magnetic stirring at a rotation speed of 400 to 600 rpm for 20 to 40 minutes.

7. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 2), the starch is one or more of taro starch, potato starch and tapioca starch.

8. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: In step 3), the critical gelatinization temperature of starch is O Obtained by DSC measurement; the stirring speed is 400-600 rpm.

9. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 1, characterized in that: The high-precision 3D printing starch-based ink obtained in step 3) is placed in a 3D printing syringe, cooled naturally, bubbles are removed, and printing is performed after adjusting the printing parameters to obtain a high-precision starch-based 3D printed product.

10. The method for preparing high-precision 3D printing starch-based ink by critical melting synergistic polysaccharide according to claim 9, characterized in that: The printing temperature in the printing parameters is set to the critical gelatinization temperature of starch T O , nozzle diameter is 0.6~1mm, and printing speed is 25~45mm / s.

Images