A heat-resistant and high-toughness degradable 3D printing material and its preparation method

Abstract

The present invention relates to the technical field of 3D printing materials, discloses a kind of heat-resistant and high-toughness degradable 3D printing material and preparation method thereof, and material is measured by mass, including the following raw material components: 60 80 parts of PLA masterbatch, 20 40 parts of PBS, 1 5 parts of compatibilizer; The PLA masterbatch includes raw material components: 80 95 parts of PLA, 5 20 parts of fillers, 2 8 parts of toughening agents, 0.1 1 parts of antioxidants, 0.1 1 parts of lubricants, 0.1 1 parts of nucleating agents, 0.1 1 parts of coupling agents. The present invention adopts PBS and PLA to blend, pre-treats the filler with a coupling agent, and then blends and extrudes the particles obtained by blending and modifying with PLA with PBS. The addition of filler can enhance the strength and heat resistance of the material, and the particles after extrusion are blended and granulated with PBS, ensure that the filler can be completely dispersed among PLA, accelerate the crystallization rate of PLA, and ultimately achieve the improvement of the heat resistance and toughness of the printed material.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing materials, and in particular to a heat-resistant and high-toughness degradable 3D printing material and a preparation method thereof. Background Art

[0002] With the development of the times, 3D printing, which can generate parts of any shape directly from computer graphics data without the need for machining or molds, significantly shortens product development cycles, improves productivity, and reduces production costs. It is gradually replacing traditional mold production and is widely used in engineering, civil engineering, medical, construction, and other industries. Amidst the global push for plastic bans, the development of biodegradable materials to replace commonly used plastics is urgent. Polylactic acid (PLA) is a new biodegradable polymer made from biomass such as corn or sugarcane. It exhibits excellent compatibility, degradability, and mechanical properties, making it widely used in extrusion, injection molding, blown film, and spinning. During the printing process, PLA requires a relatively low printing temperature, produces virtually no odor during the melt process, and exhibits high ductility and low shrinkage. However, due to its slow crystallization rate and low heat distortion temperature, PLA softens at around 55°C, causing distortion or deformation in finished products. Furthermore, PLA has poor toughness and a brittle texture, significantly limiting the application of PLA-printed products.

[0003] CN106893279A discloses a degradable 3D printing toughening material and its preparation method, comprising the following components by weight: 70-80 parts polylactic acid, 20-30 parts EVA, 6-8 parts toughening agent, 0.4-5 parts compatibilizer, and 0.2-2 parts auxiliary agent. The toughening agent is dioctyl phthalate (DOP), and the compatibilizer includes a malic anhydride grafted polymer, a terpolymer formed by copolymerization of methyl methacrylate, butadiene, and styrene copolymer; and a terpolymer (SAG) formed by styrene, acrylonitrile, and glycidyl methacrylate, wherein one or more compatibilizers are used in combination. However, this method only enhances the toughness of the material and does not provide an effective solution for enhancing heat resistance.

[0004] CN103540111A discloses a high-strength, high-temperature-resistant all-bio-polylactic acid sheet and its manufacturing method. According to the percentage by mass of the raw materials, 50%-78% of polylactic acid, 10%-30% of toughening components, 10%-30% of inorganic fillers and 1%-3% of other additives are mixed evenly, and an extruder is used to prepare the blended masterbatch, which is then used to prepare the sheet. However, according to this method, the toughness and heat resistance of the sheet actually obtained cannot reach the values ​​described, and the addition of glass fiber makes it unsuitable for use in the 3D printing industry. Therefore, the market urgently needs a biodegradable 3D printing material that is heat-resistant and has satisfactory mechanical properties. Summary of the Invention

[0005] The present invention addresses the problems of poor toughness and insufficient heat resistance of PLA materials used in 3D printing, and provides a heat-resistant, high-toughness, degradable 3D printing material with excellent heat resistance.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] A heat-resistant and highly tough biodegradable 3D printing material, comprising the following raw material components by weight: 60-80 parts of PLA masterbatch, 20-40 parts of PBS, and 1-5 parts of a compatibilizer;

[0008] The PLA masterbatch comprises raw material components: 80-95 parts of PLA, 5-20 parts of filler, 2-8 parts of toughening agent, 0.1-1 part of antioxidant, 0.1-1 part of lubricant, 0.1-1 part of nucleating agent, and 0.1-1 part of coupling agent.

[0009] The present invention utilizes a mixture of PBS and PLA. PBS has excellent biocompatibility and bioabsorbability, and it naturally degrades into water and carbon dioxide. After being blended and modified with PLA, PBS acts as a backbone within the copolymer, supporting the entire structure in high-temperature environments and buying time for PLA crystallization, thereby effectively enhancing the composite material's heat resistance.

[0010] Preferably, the degradable 3D printing material comprises the following raw material components: 65-75 parts of PLA masterbatch, 25-35 parts of PBS, and 1-5 parts of a compatibilizer. The amount of PBS and PLA used will affect the heat resistance and printing effect of the composite material. The product obtained at this ratio has better heat resistance and better printing effect.

[0011] The PLA masterbatch comprises the following raw materials: 85-95 parts PLA, 5-15 parts filler, 2-8 parts toughening agent, 0.1-1 part antioxidant, 0.1-1 part lubricant, 0.1-1 part nucleating agent, and 0.1-1 part coupling agent. The filler dosage affects the mechanical properties of the composite material, and a specific ratio yields superior mechanical properties.

[0012] Further preferably, the degradable 3D printing material comprises the following raw material components: 70-75 parts of PLA masterbatch, 25-30 parts of PBS, and 1-5 parts of a compatibilizer;

[0013] Further preferably, the PLA masterbatch comprises raw material components: 90-95 parts of PLA, 5-10 parts of filler, 2-8 parts of toughening agent, 0.1-1 part of antioxidant, 0.1-1 part of lubricant, 0.1-1 part of nucleating agent, and 0.1-1 part of coupling agent.

[0014] Preferably, the PLA has a weight average molecular weight of 120,000-190,000, a melt index of 4-10 g / 10 min, and is tested at 190° C. and 2.16 kg.

[0015] The PLA comprises any one of L-type polylactic acid and D-type polylactic acid or a mixture of the two.

[0016] Preferably, the density of the PBS is 1.2-1.28 g / cm 3 , melt index is 10-20g / 10min, test conditions are 190℃, 2.16kg;

[0017] Preferably, the compatibilizer includes one or more of a cyclic anhydride (MAH) compatibilizer, a carboxylic acid compatibilizer, an epoxy compatibilizer, and an oxazoline compatibilizer.

[0018] Further preferably, the compatibilizer is selected from one or more of AS-K25 of Shanghai Nanosu, EPDM of Coase, and HC-6 of Jinhua Hong Innovation Materials.

[0019] Preferably, the filler includes one or more of calcium carbonate, talc, mica powder, wollastonite, and montmorillonite; the filler has a particle size of no less than 2000 mesh. Mica powder with a particle size greater than 2500 mesh is further preferred. High-mesh mica powder effectively disperses in PLA, accelerating its crystallization. It also increases melt viscosity, helping PLA and PBS form a co-continuous structure rather than an island-in-the-sea structure, enhancing the heat resistance of the composite material. Furthermore, the layered structure of mica powder enhances the dimensional stability of printed samples and reduces shrinkage.

[0020] Preferably, the coupling agent includes one or more of a silane coupling agent, an aluminate coupling agent, and a titanate coupling agent.

[0021] Further preferably, the coupling agent includes any one or more of Union Carbide A-1100, Shin-Etsu KBM-903, KH-550, KH-560, Jessica Chemical HY-1804, Jessica Chemical HY-1805, Jessica Chemical HY-999, Jessica Chemical HY-133, NDZ-201, isopropyl tris(dioctyl pyrophosphate), KR-41B, and KR-TTS.

[0022] A further preferred coupling agent is an aluminate coupling agent. The inorganic and organic end groups of the coupling agent can chemically react or form entangled structures with the surface of the inorganic filler and the organic resin, respectively. This enhances interfacial compatibility and dispersibility of the inorganic powder and the organic resin after treatment with the aluminate coupling agent, resulting in improved mechanical properties of the resulting product. Examples include any one or more of Jessica Chemical HY-1804, Jessica Chemical HY-1805, Jessica Chemical HY-999, and Jessica Chemical HY-133.

[0023] Preferably, the toughening agent includes one or more of ethylene ester copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, and silicone-methyl methacrylate;

[0024] More preferably, the vinyl acetate copolymer includes VINNEX 2525 from Wacker; the ethylene-butyl acrylate-glycidyl methacrylate copolymer includes PTW from DuPont; and the organosilicon-methyl methacrylate includes any one or more of S-2001, S-2100, and S-2030 from Mitsubishi Chemical of Japan.

[0025] Preferably, the antioxidant includes one or more of diaryl secondary amine, p-phenylenediamine and ketoamine, aldehyde amine, antioxidant 1010, antioxidant 1076, phosphite, didodecyl alcohol ester, didetradecyl alcohol ester and didecyl alcohol ester; preferably, the antioxidant is antioxidant 1076, which has a lower melting point and is more compatible with the processing temperature of PLA.

[0026] Preferably, the lubricant comprises one or more of calcium stearate, zinc stearate, ethylene bisstearamide (EBS), oxidized PE wax, and oleamide;

[0027] Preferably, the nucleating agent includes one or more of sodium succinate, sodium glutarate, sodium hexanoate, potassium benzoate, lithium benzoate, sodium cinnamate, β-sodium naphthoate, ADICO NA11, ADICO NA18, ADICO NA21, Milliken NX8000, Milliken HPN 20E, and Zhejiang Chuangmo NA3011.

[0028] The present invention also provides a method for preparing the heat-resistant and high-toughness degradable 3D printing material, comprising the steps of:

[0029] Step 1: Add filler into a blender, spray a coupling agent into the blender while stirring, then add PLA, a toughening agent, an antioxidant, a lubricant, and a nucleating agent, mix, melt blend, and extrude to obtain a PLA masterbatch;

[0030] Step 2: melt-blending the PLA masterbatch, PBS and a compatibilizer, and extruding and granulating the mixture to obtain the degradable 3D printing material.

[0031] In the present invention, the filler is pretreated with a coupling agent, then blended and modified with PLA, extruded and granulated, and the resulting particles are then blended and extruded with PBS. While the addition of fillers can enhance the strength and heat resistance of the material, small amounts of fillers have limited effects on material properties, while large amounts tend to agglomerate. Therefore, pretreating the filler with a coupling agent enhances its compatibility with PLA. The extruded particles are then blended and granulated with PBS to ensure complete dispersion of the filler within the PLA, accelerating the PLA's crystallization rate and improving the heat resistance and toughness of the printed material.

[0032] Preferably, in step 1, the filler and the coupling agent are mixed for 3-5 minutes, and then other raw materials are added and mixed for 5-10 minutes. During the mixing process, the stirrer speed is 1000-2000 r / min.

[0033] Preferably, melt extrusion is performed using a twin-screw extruder at a melt extrusion temperature of 150-180°C, a screw speed of 200-300 r / min, a feed rate of 10-20 r / min, and a screw aspect ratio of 48-52:1. Preferably, the PLA masterbatch and PBS are dried in advance to remove moisture, such as by drying at 60-80°C for 2-8 hours.

[0034] Further preferably, the twin-screw extruder has 12 heating zones, with the temperatures of the following sections, starting from the die head, being: 150-160°C (section 1), 160-180°C (section 2), 160-180°C (section 3), 170-180°C (section 4), 170-180°C (section 5), 170-180°C (section 6), 160-180°C (section 7), 150-170°C (section 8), 150-170°C (section 9), 150-170°C (section 10), 150-170°C (section 11), and 160-180°C (section 12). A vent is provided in section 5, and vacuum ports are provided in sections 9 and 10. The vent removes moisture generated during extrusion, while the vacuum port removes small molecule products, thereby reducing product odor and enhancing product stability.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] (1) The present invention mixes PBS with PLA masterbatch in a suitable ratio, so that PBS can play a skeletal supporting role for PLA, thereby providing PLA with a longer crystallization time under high temperature environment, and the final product has excellent heat resistance.

[0037] (2) In the present invention, the coupling agent is used to modify the filler to enhance the mechanical properties of the PLA matrix, and all the raw materials and additives used can be completely degraded in the natural environment without causing plastic pollution.

[0038] (3) The preparation and processing temperature of the degradable 3D printing material of the present invention is low, there is no odor during the processing, and no toxic or harmful substances are produced. It is compatible with most 3D printers, and the parts produced by 3D printing have improved heat resistance, no deformation, and excellent layer adhesion and toughness. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is the SEM image of the degradable 3D printing material after etching prepared in Example 3. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiment. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Those skilled in the art will make modifications or equivalent substitutions based on understanding the technical solution of the present invention, without departing from the spirit and scope of the technical solution of the present invention, and all should be encompassed within the protection scope of the present invention.

[0041] The raw materials used in the following specific embodiments were all purchased from the market, among which PLA was purchased from Total Corbijn's LX175, PBS was purchased from PPT Chemicals of Thailand's FZ91PM, mica powder was purchased from Yuejiang New Materials' TY-100, toughening agent was purchased from DuPont's PTW, antioxidant was purchased from BASF's Irganox 1076, lubricant was purchased from KLK OLEO of Malaysia's Baomowei EBS, nucleating agent was purchased from Chuangmo New Materials' NA3011, coupling agent was purchased from Jessica Chemical's isopropyl distearate acyloxyaluminate (HY-999), and compatibilizer was purchased from Jinhua Hong Innovation Materials' HC-6.

[0042] The prepared heat-resistant and high-toughness biodegradable 3D printing materials were tested using the following test methods: mechanical property test: using GB / T 1040.1-2018, Vicat temperature test: using GB / T1633-2000.

[0043] The twin-screw extruder used in the following specific embodiment has an aspect ratio of 50 and 12 heating zones. The temperatures of each zone from the die head are: 150°C in the first zone, 170°C in the second zone, 170°C in the third zone, 175°C in the fourth zone, 175°C in the fifth zone, 180°C in the sixth zone, 170°C in the seventh zone, 165°C in the eighth zone, 165°C in the ninth zone, 160°C in the tenth zone, 165°C in the eleventh zone, and 170°C in the twelfth zone. An exhaust port is provided in the fifth zone, and vacuum ports are provided in the ninth and tenth zones. The screw speed during extrusion granulation is 300 r / min and the feed rate is 15 r / min.

[0044] Example 1

[0045] Add 10 parts mica powder to a blender. While stirring, add 0.5 parts coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 90 parts PLA, 2 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, and 0.5 parts EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0046] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 70 parts of PLA masterbatch, 30 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A1.

[0047] Example 2

[0048] Add 10 parts mica powder to a blender. While stirring, add 0.5 parts coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 90 parts PLA, 2 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, and 0.5 parts EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0049] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 65 parts of PLA masterbatch, 35 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A2.

[0050] Example 3

[0051] Add 10 parts mica powder to a blender. While stirring, add 0.5 parts coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 90 parts PLA, 2 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, and 0.5 parts EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0052] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 60 parts of PLA masterbatch, 40 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A3.

[0053] SEM phase morphology observation: The particles obtained in Example 3 were pressed into round pieces by a tablet press. The round pieces were etched with dichloromethane for 12 hours, and then placed in a vacuum oven at 50°C for 12 hours. After drying, the pieces were sprayed with gold for 90 seconds, and then observed under an electron scanning microscope. The results are as follows: Figure 1 As shown in the figure, a co-continuous structure is formed after blending PLA and PBS. This indicates that during the printing process, PBS provides a supporting skeleton for PLA, which is conducive to the crystallization of PLA, thereby improving the heat resistance of the product.

[0054] Example 4

[0055] Add 10 parts mica powder to a blender. While stirring, add 0.5 parts coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 90 parts PLA, 2 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, and 0.5 parts EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0056] The PLA masterbatch and PBS were placed in an oven at 80°C and dried for two hours. 75 parts of PLA masterbatch, 25 parts of PBS and 2 parts of compatibilizer were taken to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was marked as A4.

[0057] Example 5

[0058] Add 15 parts of mica powder to a blender. While stirring, add 0.5 parts of coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 85 parts of PLA, 2 parts of PTW, 0.2 parts of 1076, 0.8 parts of NA3011, and 0.5 parts of EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0059] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 65 parts of PLA masterbatch, 35 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A5.

[0060] Example 6

[0061] Add 20 parts of mica powder to a blender. While stirring, add 0.5 parts of coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 80 parts of PLA, 2 parts of PTW, 0.2 parts of 1076, 0.8 parts of NA3011, and 0.5 parts of EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0062] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 65 parts of PLA masterbatch, 35 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A6.

[0063] Example 7

[0064] Add 5 parts of mica powder to a blender. While stirring, add 0.5 parts of coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 95 parts of PLA, 2 parts of PTW, 0.2 parts of 1076, 0.8 parts of NA3011, and 0.5 parts of EBS to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain PLA masterbatch.

[0065] The above PLA masterbatch and PBS were placed in an 80°C oven and dried for two hours. 65 parts of PLA masterbatch, 35 parts of PBS and 2 parts of compatibilizer were blended and extruded into granules through a twin-screw extruder to obtain a heat-resistant and high-toughness biodegradable 3D printing material, which was recorded as A7.

[0066] Comparative Example 1

[0067] The white PLA 3D printing material purchased from Dezhijian on the market is marked as B1.

[0068] Comparative Example 2

[0069] 55 parts PLA, 35 parts PBS, 10 parts mica powder, 3 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, 0.5 parts EBS, and 2 parts compatibilizer were mixed in a high-speed blender at 2000 rpm for 5 minutes. After mixing, the mixture was melt-extruded through a twin-screw extruder, passed through a cooling water tank, blower, and pelletizer, yielding a heat-resistant, high-toughness biodegradable 3D printing material, designated B2.

[0070] Comparative Example 3

[0071] Add 10 parts of mica powder to a blender and, while stirring, add 0.5 parts of coupling agent via a spray bottle. Stir at 1000 rpm for 3 minutes. Then, add 90 parts of PLA, 2 parts of PTW, 0.2 parts of 1076, 0.8 parts of NA3011, 0.5 parts of EBS, and 2 parts of a compatibilizer to a high-speed blender and stir for 5 minutes at 2000 rpm. After mixing, melt extrude the mixture through a twin-screw extruder, pass through a cooling water tank, blower, and pelletizer, and obtain resin pellets, designated B3.

[0072] Comparative Example 4

[0073] 65 parts PLA, 35 parts PBS, 2 parts PTW, 0.2 parts 1076, 0.8 parts NA3011, 0.5 parts EBS, and 2 parts compatibilizer were added to a high-speed blender and stirred for 5 minutes at 2000 rpm. After mixing, the mixture was melt-extruded through a twin-screw extruder, passed through a cooling water tank, blower, and pelletizer, and obtained resin pellets, designated B4.

[0074] The 3D printing materials prepared in the examples and comparative examples were sampled and their properties were tested. The results are shown in Table 1.

[0075] Table 1 Mechanical and heat-resistant properties of 3D printing materials of Examples and Comparative Examples

[0076]

[0077] The 3D printing materials prepared in the examples and comparative examples were printed, the state during the printing process was observed, and the heat resistance of the samples was tested. The results are shown in Table 2. The specific steps of the heat resistance test include:

[0078] (1) Heat-resistant model preparation: The prepared heat-resistant and high-toughness biodegradable 3D printing material is placed in an 85°C oven for 2 hours, then melt-extruded through a single-screw extruder, passed through a cooling water tank, a diameter gauge, and an automatic winder to be wound into a coil. The temperature of the single-screw extruder is 170-190°C, and the wire diameter must be controlled within 1.75±0.05mm.

[0079] The prepared wire drum was printed using a 3D printer. The printed model was a hollow cuboid with a base plate measuring 120 mm long, 60 mm wide, and 40 mm high. The printer temperature was 190-210°C, and the base plate temperature was 60°C.

[0080] (2) Test method: The printed models were placed in a 90°C oven for half an hour, the height difference after the model collapsed was measured, and the sample deformation rate was calculated.

[0081] Table 2 Printing conditions and sample deformation rates of 3D printing materials of the embodiment and comparative example

[0082] Serial number Printing status Sample deformation rate (%) A1 Smooth 3.5 A2 Smooth 2.1 A3 The bottom plate is slightly warped and deformed 1.4 A4 Smooth 2.7 A5 The model is slightly cracked and deformed 2.5 A6 The model is slightly cracked and deformed 2.2 A7 Smooth 2.8 B1 Smooth 68.4 B2 Smooth 34.1 B3 Smooth 43.7 B4 Smooth 21.6

[0083] The results in Tables 1 and 2 show that the heat-resistant, high-toughness, degradable 3D printing materials produced in Examples 1-7 significantly outperform commercially available printing materials. By observing Examples 1-4 and Comparative Example 1, it can be seen that the heat resistance and mechanical properties of the materials gradually improve with increasing PBS addition. However, when the addition exceeds 35 parts, while the heat resistance continues to improve, the mechanical properties of the material begin to decline, and slight warping and deformation may occur during printing.

[0084] By observing Examples 2, 5, 6, and 7 and Comparative Example 1, it can be seen that when the mica powder addition ratio exceeds 10 parts, the mechanical properties of the material will gradually decrease. At the same time, the layer viscosity deteriorates during printing, resulting in slight deformation of the printed model. If it exceeds 20 parts, further increasing the filler dosage will prevent smooth printing.

[0085] By observing Example 2 and Comparative Examples 2-4, it can be seen that the performance of the filler and PBS added together is better than adding only a single component, and the performance of the material obtained by pretreating the filler with a coupling agent to prepare a PLA masterbatch and then blending and extruding it with PBS is far better than direct blending.

Claims

1. A heat-resistant and high-toughness degradable 3D printing material, characterized in that: The degradable 3D printing material includes the following raw material components by weight: 65-75 parts of PLA masterbatch, 25-35 parts of PBS, and 1-5 parts of a compatibilizer; The PLA masterbatch comprises raw material components: 85-95 parts of PLA, 5-15 parts of filler, 2-8 parts of toughening agent, 0.1-1 part of antioxidant, 0.1-1 part of lubricant, 0.1-1 part of nucleating agent, and 0.1-1 part of coupling agent; the filler is mica powder; The preparation method of the degradable 3D printing material comprises the following steps: Step 1: Add filler into a blender, spray a coupling agent into the blender while stirring, then add PLA, a toughening agent, an antioxidant, a lubricant, and a nucleating agent, mix, melt blend, and extrude to obtain a PLA masterbatch; Step 2, melt-blending the PLA masterbatch, PBS and a compatibilizer, and extruding and granulating to obtain the degradable 3D printing material; In step 1, the filler and coupling agent are mixed for 3-5 minutes, and then other raw materials are added and mixed for 5-10 minutes. The stirrer speed during the mixing process is 1000-2000 r / min. The melt extrusion adopts a twin-screw extruder with a melt extrusion temperature of 150-180°C, a screw speed of 200-300 r / min, a feed rate of 10-20 r / min, and a screw length-diameter ratio of 48-52:1; The twin-screw extruder has 12 heating sections, and the temperatures of each section from the head are: 150-160°C for the first section, 160-180°C for the second section, 160-180°C for the third section, 170-180°C for the fourth section, 170-180°C for the fifth section, 170-180°C for the sixth section, 160-180°C for the seventh section, 150-170°C for the eighth section, 150-170°C for the ninth section, 150-170°C for the tenth section, 150-170°C for the eleventh section, and 160-180°C for the twelfth section, wherein an exhaust port is provided in the fifth section, and vacuum ports are provided in the ninth and tenth sections.

2. The heat-resistant and high-toughness degradable 3D printing material according to claim 1, characterized in that: The PLA has a weight average molecular weight of 120,000-190,000 and a melt index of 4-10 g / 10 min, and the test conditions are 190° C. and 2.16 kg; And / or, the density of the PBS is 1.2-1.28 g / cm 3 , melt index is 10-20 g / 10min, test conditions are 190℃, 2.16kg; And / or, the compatibilizer includes one or more of a cyclic anhydride compatibilizer, a carboxylic acid compatibilizer, an epoxy compatibilizer, and an oxazoline compatibilizer.

3. The heat-resistant and high-toughness degradable 3D printing material according to claim 1, characterized in that: The particle size of the filler is not less than 2000 mesh; And / or, the coupling agent includes one or more of a silane coupling agent, an aluminate coupling agent, and a titanate coupling agent.

4. The heat-resistant and high-toughness degradable 3D printing material according to claim 3, characterized in that: The coupling agent includes any one or more of Union Carbide A-1100, Shin-Etsu KBM-903, KH-550, KH-560, Jessica Chemical HY-1804, Jessica Chemical HY-1805, Jessica Chemical HY-999, Jessica Chemical HY-133, NDZ-201, KR-41B, and KR-TTS.

5. The heat-resistant and high-toughness degradable 3D printing material according to claim 1, characterized in that: The toughening agent includes one or more of ethylene ester copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, and silicone-methyl methacrylate; and / or, the antioxidant comprises one or more of diaryl secondary amine, ketoamine, aldehyde amine, antioxidant 1010, antioxidant 1076, phosphite, didodecanol ester, didetradecyl ester and didecyl ester; And / or, the lubricant includes one or more of calcium stearate, zinc stearate, ethylene bisstearamide, oxidized PE wax, and oleamide; And / or, the nucleating agent includes one or more of sodium succinate, sodium glutarate, sodium hexanoate, potassium benzoate, lithium benzoate, sodium cinnamate, β-sodium naphthoate, ADICO NA11, ADICO NA18, ADICO NA21, Milliken NX8000, Milliken HPN 20E, and Zhejiang Chuangmo NA3011.

6. The method for preparing the heat-resistant and high-toughness degradable 3D printing material according to any one of claims 1 to 5, characterized in that: Including steps: Step 1: Add filler into a blender, spray a coupling agent into the blender while stirring, then add PLA, a toughening agent, an antioxidant, a lubricant, and a nucleating agent, mix, melt blend, and extrude to obtain a PLA masterbatch; Step 2: melt-blending the PLA masterbatch, PBS and a compatibilizer, and extruding and granulating the mixture to obtain the degradable 3D printing material.

7. The method for preparing the heat-resistant and high-toughness degradable 3D printing material according to claim 6, characterized in that: In step 1, the filler and the coupling agent are mixed for 3-5 minutes, and then other raw materials are added and mixed for 5-10 minutes. During the mixing process, the stirrer speed is 1000-2000 r / min.

8. The method for preparing the heat-resistant and high-toughness degradable 3D printing material according to claim 6, characterized in that: The melt extrusion adopts a twin-screw extruder, the melt extrusion temperature is 150-180°C, the screw speed is 200-300 r / min, the feeding speed is 10-20 r / min, and the screw length-diameter ratio is 48-52:

1.

9. The method for preparing the heat-resistant and high-toughness degradable 3D printing material according to claim 6, characterized in that: The twin-screw extruder has 12 heating sections, and the temperatures of each section from the head are: 150-160°C for the first section, 160-180°C for the second section, 160-180°C for the third section, 170-180°C for the fourth section, 170-180°C for the fifth section, 170-180°C for the sixth section, 160-180°C for the seventh section, 150-170°C for the eighth section, 150-170°C for the ninth section, 150-170°C for the tenth section, 150-170°C for the eleventh section, and 160-180°C for the twelfth section, wherein an exhaust port is provided in the fifth section, and vacuum ports are provided in the ninth and tenth sections.

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