Low-adhesion high-performance 3D printing polymer composite material and preparation method thereof

Abstract

The invention relates to the technical field of ultraviolet curing 3D printing materials, and discloses a low-adhesion high-performance 3D printing polymer composite material and a preparation method thereof, the composite material comprises the following components by mass: 60-75 parts of modified acrylate photosensitive resin; 10 to 20 parts of polyurethane acrylate resin; 1-5 parts of a hydrophobic organic silicon modifier; 0.5 to 3 parts of fluorinated silicon dioxide powder; 5 to 15 parts of a styrene-butadiene block copolymer; 1 to 5 parts of 2-hydroxy-2-methyl-1-phenylacetone, and 1 to 5 parts of 2-hydroxy-2-methyl-1-phenylacetone; 0.5 to 3 parts of polyethylene glycol dimethacrylate; 0.5 to 2 parts of an ultraviolet absorbent; 0.5 to 2 parts of a rheology regulating agent; the preparation method comprises the following steps: mixing modified acrylate with polyurethane acrylate, sequentially adding an organic silicon modifier, fluorinated silicon dioxide, a functional additive and a photoinitiator, and carrying out dispersing, defoaming and filtering treatment to prepare the low-adhesion high-performance 3D printing polymer composite material. The composite material disclosed by the invention has the advantages of good demolding property and excellent mechanical property.

Description

Technical Field

[0001] The present invention relates to the technical field of ultraviolet-curable 3D printing materials, specifically a low-adhesion and high-performance 3D printing polymer composite material and its preparation method. Background Art

[0002] With the continuous progress of 3D printing technology, ultraviolet-curable resin materials have been widely used in multiple industries, such as education, medical, art creation, industrial prototyping, etc. As a key 3D printing material, ultraviolet-curable resin can provide high precision and excellent surface quality, especially suitable for printing requirements that need complex geometries and high customization. However, existing photocurable resin materials still face some problems in practical applications, mainly in terms of low adhesion and high performance.

[0003] Currently, many traditional ultraviolet-curable resins rely on strong intermolecular interactions to ensure the adhesion of printed parts. Although this can improve the adhesion between the printed part and the platform, it causes great difficulties in the demolding process. The overly strong binding force between the cured resin and the printing platform often leads to damage or surface damage of the printed part when peeled off. Especially in mass production and high-precision printing applications, the difficult demolding not only increases the complexity of post-processing but also may affect the production efficiency and quality consistency of products.

[0004] In addition to the demolding performance problem, existing photocurable resins also have certain limitations in mechanical properties. Although most resins show good strength and toughness during the initial printing process, their wear resistance, impact resistance, and heat resistance are insufficient during long-term use, often making it difficult to meet the high-performance requirements in industrial manufacturing and engineering applications. Especially for scenarios that require long-term load or complex external forces, traditional resins often show low durability and mechanical strength, restricting their application in high-end product manufacturing.

[0005] Therefore, the present invention proposes a low-adhesion and high-performance 3D printing polymer composite material and its preparation method to solve the deficiencies of the prior art. Summary of the Invention

[0006] In view of the deficiencies of the prior art, the present invention provides a low-adhesion and high-performance 3D printing polymer composite material and its preparation method, which solves the problems of difficult demolding and insufficient mechanical properties of traditional resin materials.

[0007] To achieve the above objectives, the present invention is realized through the following technical solutions: A low-adhesion and high-performance 3D printing polymer composite material, comprising the following components in parts by mass: Modified acrylate photosensitive resin: 60 - 75 parts; Polyurethane acrylate resin: 10 - 20 parts; Hydrophobic silicone modifier: 1 - 5 parts; Fluorinated silica powder: 0.5 - 3 parts; Styrene-butadiene block copolymer: 5 - 15 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 1 - 5 parts; Polyethylene glycol dimethacrylate: 0.5 - 3 parts; Ultraviolet absorber: 0.5 - 2 parts; Rheology regulator: 0.5 - 2 parts.

[0008] Preferably, the modified acrylate photosensitive resin is composed of trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, and the mass ratio of trimethylolpropane triacrylate to poly-2-hydroxypropyl methacrylate is 3:1 - 5:1.

[0009] Preferably, the hydrophobic silicone modifier is a copolymer of hydroxyl-terminated polydimethylsiloxane and methyl methacrylate, and the mass ratio of hydroxyl-terminated polydimethylsiloxane to methyl methacrylate is 3:1 - 5:1.

[0010] Preferably, the particle size of the fluorinated silica powder is 50 - 150 nanometers, and the specific surface area is 100 - 200 m 2 / g.

[0011] Preferably, the styrene-butadiene block copolymer is a copolymer of styrene and butadiene, and the mass ratio of styrene to butadiene is 2:1 - 3:1.

[0012] The present invention also provides a method for preparing a low-adhesion and high-performance 3D printing polymer composite, comprising the following steps: S1. Mix the modified acrylate photosensitive resin and the polyurethane acrylate resin evenly to obtain a first mixture; S2. Add the hydrophobic silicone modifier and the fluorinated silica powder to the first mixture, stir and disperse to obtain a second mixture; S3. Add the ultraviolet absorber, polyethylene glycol dimethacrylate, rheology regulator and styrene-butadiene block copolymer to the second mixture, mix evenly to obtain a third mixture; S4. Add 2-hydroxy-2-methyl-1-phenylpropanone to the third mixture under light-shielded conditions, stir evenly to obtain a fourth mixture; S5. Place the fourth mixture under vacuum conditions for degassing treatment and filter it through a sieve to obtain a low-adhesion and high-performance 3D printing polymer composite.

[0013] Preferably, in step S1, the mixing temperature is 20-30°C and the stirring time is 10-15 minutes.

[0014] Preferably, in step 2, high-speed dispersing machine is used for stirring and dispersing at 2000-3000 rpm for 15-20 minutes.

[0015] Preferably, in step S3, the mixing temperature is 25-35°C and the time is 10-15 minutes; in step S4, the stirring is carried out under light-shielding conditions for 5-10 minutes.

[0016] Preferably, in step S5, the vacuum degree for degassing treatment is -0.08 to -0.1 MPa, the time is 15-20 minutes, and the screen filtration is carried out with a screen of 80-150 meshes.

[0017] The present invention provides a low-adhesion and high-performance 3D printing polymer composite material and its preparation method. It has the following beneficial effects: 1. The present invention adopts the technical scheme of a hydrophobic silicone modifier, achieving the technical effect of effectively reducing the demolding force. Compared with the traditional resin formulations used in the prior art, the present invention forms a hydrophobic interface on the material surface through modification, greatly reducing the adhesion force with the printing platform, and solving the problems of difficult demolding and easy surface damage of traditional resins.

[0018] 2. The present invention introduces the innovative application of styrene-butadiene block copolymer, optimizing the elasticity and toughness of the resin. Compared with the existing resin formulations, the systems lacking this copolymer usually perform poorly during high-strength printing, prone to cracks or uneven curing, resulting in unstable forming quality. Through this technical scheme, the present invention improves the flexibility and stress distribution of the material, effectively avoiding the common peeling damage phenomenon.

[0019] 3. The present invention removes the bubbles in the resin through a vacuum degassing process, ensuring the surface smoothness and stability of the printed parts. Compared with the common filtration treatment in the prior art, the degassing process can effectively avoid bubble residues, reduce the influence of surface bubbles on the demolding force during demolding, ensure the integrity of the printed parts, and avoid cracking or uneven demolding resistance caused by bubbles.

[0020] 4. The present invention adopts the technical scheme of a modified acrylate photosensitive resin, achieving the technical effect of improving the demolding performance. Compared with the formulations without adding the modified acrylate photosensitive resin in the prior art, the resins without adding the modified acrylate show a higher demolding force and are prone to problems such as tearing or corner warping. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a flow chart of the preparation method of the present invention. Detailed implementation manners

[0022] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0023] In the following examples, comparative examples and experiments, trimethylolpropane triacrylate is MR2301, from Haohui New Materials (Guangdong Haohui New Materials Co., Ltd.); The polyurethane acrylate resin is Fujida PUA-120; The hydroxyl-terminated polydimethylsiloxane is Ocean silicone oil ZH-300; The methyl methacrylate is Sinopec MMA 99%; The fluorinated silica powder is Lier fluorosilicate; The styrene is Sinopec styrene; The butadiene is CNPC butadiene; The 2-hydroxy-2-methyl-1-phenylpropanone is Huaxin HMP; The polyethylene glycol dimethacrylate is Dongyuan PEGDMA; The ultraviolet absorber is UV-234; The rheology regulator is Acrysol RM-8, an acrylic rheology regulator.

[0024] Please refer to Figure 1 , the present invention provides a low-adhesion and high-performance 3D printing polymer composite material, including the following components in parts by mass: Modified acrylate photosensitive resin: 60-75 parts; Polyurethane acrylate resin: 10-20 parts; Hydrophobic silicone modifier: 1-5 parts; Fluorinated silica powder: 0.5-3 parts; Styrene-butadiene block copolymer: 5-15 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 1-5 parts; Polyethylene glycol dimethacrylate: 0.5-3 parts; Ultraviolet absorber: 0.5-2 parts; Rheology regulator: 0.5-2 parts.

[0025] Modified acrylate photosensitive resin: The modified acrylate photosensitive resin is composed of trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, and the mass ratio is controlled within the range of 3:1 - 5:1, and it is used in the composite material in a mass fraction of 60 - 75 parts. This combination maintains a relatively high double bond density in the system while introducing a certain proportion of hydrophilic functional groups, improving its flexibility and dispersibility, and helping other subsequent components to be evenly embedded in the main chain cross-linking network.

[0026] Trimethylolpropane triacrylate provides trifunctional groups, which is beneficial to form a highly cross-linked three-dimensional structure under photo-initiation conditions, enhancing the structural stability of the material. The hydroxyl structure introduced by 2-hydroxypropyl methacrylate increases the polarity of the system, helps to improve the interfacial affinity between the resin and functional fillers (such as inorganic particles, polymer blocks, etc.), and moderately reduces the cross-linking density, avoiding embrittlement caused by over-crosslinking of the system.

[0027] Polyurethane acrylate resin: The polyurethane acrylate resin is added to the composite material in a mass fraction of 10 - 20 parts and participates in the photocuring reaction as a flexible regulating component. The molecular structure of this resin contains polymerizable double bonds and also contains flexible polyether or polyester segments, having good toughness and ductility.

[0028] The soft segment in the polyurethane segment provides the degree of freedom of molecular movement, enhances the buffering ability of the material during tensile deformation, and also has a certain effect of releasing the internal stress generated by curing shrinkage. The elastic domain constructed by it in the system can improve the continuity and flexibility of the curing network, thereby enhancing the overall anti-cracking ability and durability of the printed parts.

[0029] Hydrophobic organosilicon modifier: The hydrophobic organosilicon modifier is composed of hydroxy-terminated polydimethylsiloxane and methyl methacrylate copolymerization, and the mass ratio is controlled between 3:1 - 5:1, and it is used in the composite material in a mass fraction of 1 - 5 parts. This component has both the hydrophobic properties of organosilicon and the polymerization activity of acrylate, and can effectively embed in the main cross-linking network to construct a low surface energy interface.

[0030] The main chain of hydroxy-terminated polydimethylsiloxane has a tendency to migrate to the surface of the material, and can form a hydrophobic coating layer during the curing process, thereby reducing the adhesion effect with the forming platform or tank wall during the printing process. The methyl methacrylate part participates in the polymerization of the main system to ensure that the modifier is evenly distributed and fixed inside the material system, avoiding precipitation or aggregation.

[0031] Fluorinated silica powder: The fluorinated silica powder is added to the composite material in a mass fraction of 0.5 - 3 parts, with a particle size of 50 - 150 nanometers and a specific surface area of 100 - 200m 2 / g. This powder is used as an inorganic functional filler to improve the dimensional stability and mechanical uniformity of the system.

[0032] After fluorination treatment, the surface of silica has hydrophobicity, enhanced interfacial compatibility with the organic phase, and can be evenly distributed inside the system, improving the structural compactness of the composite material. Its nano-scale particle size makes it difficult to form stress concentration points during the filling process, while the large specific surface area is conducive to forming effective interfacial interactions, thereby enhancing the thermal stability and durability of the printed parts.

[0033] Styrene-butadiene block copolymer: The styrene-butadiene block copolymer exists in the composite material in a mass fraction of 5 - 15 parts, and the mass ratio of styrene to butadiene is controlled in the range of 2:1 - 3:1. This copolymer, as a thermoplastic elastomeric component, has the characteristics of a phase-separated structure.

[0034] The styrene segment in the copolymer forms a rigid phase structure, and the butadiene segment forms a flexible continuous phase, forming a microphase structure in the photocurable resin, improving the overall elongation at break and resilience. The elastic phase can undergo reversible deformation under stress, dispersing the external force load, thereby enhancing the impact resistance and dimensional recovery of the printed parts.

[0035] 2-Hydroxy-2-methyl-1-phenylpropanone: 2-Hydroxy-2-methyl-1-phenylpropanone is added to the composite material in a mass ratio of 1 - 5 parts and is used as an ultraviolet initiator to adapt to the photocuring system under the conditions of a conventional 405 nm light source. This initiator has good light absorption efficiency and free radical release ability.

[0036] After being irradiated by ultraviolet light, this initiator can rapidly cleave to generate free radicals, effectively initiating the polymerization reaction of acrylate double bonds in the resin system. The hydroxyl group in its molecular structure also improves the dispersion stability in the resin system, reducing the aggregation or precipitation of the initiator and ensuring the consistency of the curing reaction throughout the printing process.

[0037] Polyethylene glycol dimethacrylate: Polyethylene glycol dimethacrylate is added to the composite material in an amount of 0.5 - 3 parts and is used as an active diluent and flow regulating monomer. This component has a flexible main chain structure and polymerizable active groups at both ends, taking into account both dilution and reactivity.

[0038] Its polyether chain segment imparts good fluidity and wettability to the system, helping to improve the filling performance of the material in the detailed areas during the printing process. At the same time, its double-end acrylate structure can copolymerize with the system, avoiding the occurrence of non-crosslinked regions and ensuring the complete structural continuity of the formed parts.

[0039] Ultraviolet absorber: The ultraviolet absorber is added to the composite material in a mass ratio of 0.5 - 2 parts, which is used to improve the light stability of the printed part. This component can absorb high-energy ultraviolet bands on the resin surface or near the surface layer, preventing the material from undergoing undesired cross-linking reactions due to scattered light in the non-exposed area.

[0040] Its molecular structure has a conjugated system, which can effectively absorb the energy of short-wave ultraviolet rays, reducing over-curing, discoloration or degradation problems in the photosensitive area of the material. Especially under application conditions of long-term exposure to ambient light, it is beneficial to maintain the performance stability and appearance integrity of the printed part.

[0041] Rheology regulator: The rheology regulator is introduced into the composite material in a mass ratio of 0.5 - 2 parts, mainly used to adjust the shear response and static holding characteristics of the system during printing. This component forms a reversible network or physical entanglement structure in the system, dynamically regulating the viscosity of the system.

[0042] Under the action of external shear force, the regulator can make the material exhibit good fluidity, adapting to the printing ejection or filling process; in the absence of shear, it restores its three-dimensional structure, inhibits the flow of the system, and helps to maintain the clarity of the formed profile boundary and the consistency of the interlayer structure.

[0043] The present invention also provides a method for preparing a low-adhesion and high-performance 3D printing polymer composite material, including the following steps: S1. Mix the modified acrylate photosensitive resin and the polyurethane acrylate resin evenly to obtain a first mixture; S2. Add a hydrophobic silicone modifier and fluorinated silica powder to the first mixture, stir and disperse to obtain a second mixture; S3. Add an ultraviolet absorber, polyethylene glycol dimethacrylate, a rheology regulator and a styrene-butadiene block copolymer to the second mixture, and mix evenly to obtain a third mixture; S4. Add 2-hydroxy-2-methyl-1-phenylpropanone to the third mixture under light-shielded conditions, and stir evenly to obtain a fourth mixture; S5. Place the fourth mixture under vacuum conditions for degassing treatment and filter it through a sieve to obtain a low-adhesion and high-performance 3D printing polymer composite material.

[0044] For step S1, mix the modified acrylate photosensitive resin and the polyurethane acrylate resin evenly to obtain a first mixture. The mixing temperature is controlled at 20 - 30 °C, and the stirring time is 10 - 15 minutes. In this process, the modified acrylate photosensitive resin serves as the basic component, providing the active double bonds required for photocuring, while the polyurethane acrylate resin enhances the flexibility and impact resistance of the material.

[0045] The temperature and stirring time in this step are controlled within a suitable range to ensure that the two resins are fully mixed. The temperature is controlled at 20-30°C to help maintain the fluidity of the resin and avoid volatilization or unnecessary chemical reactions caused by excessive temperature. The stirring time is 10-15 minutes to ensure the uniformity of the resin system and avoid excessive stirring that may cause resin degradation or abnormal viscosity.

[0046] In step S2, a hydrophobic organosilicon modifier and fluorinated silicon dioxide powder are added to the first mixture, and the mixture is stirred and dispersed to obtain a second mixture. The stirring in this step is performed using a high-speed disperser at a speed of 2000 to 3000 rpm for 15 to 20 minutes.

[0047] The addition of hydrophobic organosilicon modifier and fluorinated silica powder significantly improves the surface properties of the composite material. The use of a high-speed disperser ensures the uniform dispersion of fluorinated silica powder and effectively prevents filler aggregation. Controlling the stirring speed of 2000-3000rpm and the stirring time of 15-20 minutes can fully disperse the organosilicon modifier and inorganic filler, enhance the uniformity of the resin, and avoid the formation of bubbles or other uneven components due to too long or too fast stirring time.

[0048] In step S3, the ultraviolet absorber, polyethylene glycol dimethacrylate, rheology control agent and styrene-butadiene block copolymer are added to the second mixture and mixed evenly to obtain a third mixture. The mixing temperature is controlled at 25-35° C. and the mixing time is 10-15 minutes.

[0049] The selection of temperature and stirring time is to ensure that all components are evenly dispersed in the resin to achieve the best mixing effect. By controlling the mixing temperature within the range of 25-35°C, it is ensured that additives such as UV absorbers, polyethylene glycol dimethacrylate, and rheology modifiers can be fully dissolved and evenly distributed without causing degradation or precipitation of certain components due to excessive temperature. The mixing time is controlled to 10-15 minutes to ensure that all components are fully integrated in the resin system and improve the light curing performance and fluidity of the material.

[0050] In step S4, 2-hydroxy-2-methyl-1-phenylpropanone is added to the third mixture and stirred evenly to obtain a fourth mixture. This step needs to be performed under light-proof conditions and the stirring time is 5 to 10 minutes.

[0051] 2-Hydroxy-2-methyl-1-phenylpropanone, as a photoinitiator, releases free radicals under ultraviolet irradiation to promote the polymerization of acrylate double bonds in the resin system. The design of stirring in the dark avoids the premature activation of the photoinitiator due to exposure to light sources before use, ensuring that the photoinitiation reaction only occurs in subsequent steps. A stirring time of 5 to 10 minutes is sufficient to uniformly disperse the photoinitiator in the resin system, avoiding aggregation or uneven distribution, and ensuring the efficiency and uniformity of the photocuring process.

[0052] For step S5, the fourth mixture is placed under vacuum conditions for degassing treatment and filtered through a sieve to obtain a 3D printing polymer composite material. The degree of vacuum for the degassing treatment is -0.08 to -0.1 MPa, the degassing time is 15 to 20 minutes, and the sieve filtration uses a sieve with 80 - 150 mesh to obtain a low-adhesion and high-performance 3D printing polymer composite material.

[0053] The degassing step effectively reduces the tiny bubbles in the material by removing bubbles in a vacuum environment, avoiding layer discontinuity or surface defects caused by bubbles during the printing process. The sieve filtration further removes impurities or unreacted particles, ensuring the purity and stability of the material. Controlling the degree of vacuum to -0.08 to -0.1 MPa can effectively remove most of the bubbles, and setting the time to 15 to 20 minutes helps to ensure the thoroughness of the degassing process and avoid printing defects caused by residual bubbles.

[0054] Example 1: Raw material ratio (parts by mass): Modified acrylate photosensitive resin (composed of trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, mass ratio 3:1): 65 parts; Polyurethane acrylate resin: 10 parts; Hydrophobic silicone modifier (composed of hydroxyl-terminated polydimethylsiloxane and methyl methacrylate, mass ratio 4:1): 1 part; Fluorinated silica powder (particle size 80 nm): 0.5 part; Styrene-butadiene block copolymer (mass ratio of styrene to butadiene 2.5:1): 5 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 1 part; Polyethylene glycol dimethacrylate: 0.5 part; Ultraviolet absorber: 0.5 part; Rheology regulator: 0.5 part.

[0055] Preparation steps: At 25°C, the modified acrylate photosensitive resin and the polyurethane acrylate resin are mixed at a stirring speed of 300 revolutions per minute for 12 minutes to obtain the first mixture; Add a hydrophobic silicone modifier and fluorinated silica powder to the first mixture, and stir at a high speed of 3000 revolutions per minute for 15 minutes, with the temperature controlled at 35 °C to obtain a second mixture; Add an ultraviolet absorber, polyethylene glycol dimethacrylate, a rheology regulator, and a styrene-butadiene block copolymer, and stir at 800 revolutions per minute at 35 °C for 10 minutes to obtain a third mixture; Under light-shielded conditions, add 2-hydroxy-2-methyl-1-phenylpropanone to the third mixture, with a stirring speed of 400 revolutions per minute and a time of 5 minutes to obtain a fourth mixture; Place the fourth mixture in a vacuum environment (vacuum degree of -0.09 MPa) for defoaming for 20 minutes, and filter using a 120-mesh sieve to obtain a low-adhesion high-performance 3D printing polymer composite.

[0056] Example 2: Raw material ratio (parts by mass): Modified acrylate photosensitive resin (composed of trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, mass ratio 4:1): 75 parts; Polyurethane acrylate resin: 20 parts; Hydrophobic silicone modifier (hydroxyl-terminated polydimethylsiloxane and methyl methacrylate, mass ratio 3:1): 5 parts; Fluorinated silica powder (particle size 100 nm): 3 parts; Styrene-butadiene block copolymer (mass ratio of styrene to butadiene 5:1): 15 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 5 parts; Polyethylene glycol dimethacrylate: 3 parts; Ultraviolet absorber: 2 parts; Acrylic rheology regulator: 2 parts.

[0057] Preparation steps: At 28 °C, stir the modified acrylate photosensitive resin and polyurethane acrylate resin at 400 revolutions per minute for 10 minutes to obtain a first mixture; Add a hydrophobic silicone modifier and fluorinated silica powder, and stir at a high speed of 2800 revolutions per minute for 18 minutes, with the temperature controlled not exceeding 40 °C to obtain a second mixture; Add polyethylene glycol dimethacrylate, ultraviolet absorber, rheology regulator, and styrene-butadiene block copolymer, and stir at 700 revolutions per minute at 35 °C for 12 minutes to obtain a third mixture; In a light-shielded environment, add 2-hydroxy-2-methyl-1-phenylpropanone, stir at a speed of 400 revolutions per minute for 8 minutes to obtain a fourth mixture; Defoam for 15 minutes under a vacuum of -0.08 MPa, and filter using a 100-mesh sieve to obtain a low-adhesion and high-performance 3D printing polymer composite material.

[0058] Example 3: Raw material ratio (parts by mass): Modified acrylate photosensitive resin (trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, mass ratio 5:1): 70 parts; Polyurethane acrylate resin: 15 parts; Hydrophobic silicone modifier: 3 parts; Fluorinated silica powder: 2 parts; Styrene-butadiene block copolymer: 10 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 3 parts; Polyethylene glycol dimethacrylate: 1.5 parts; Ultraviolet absorber: 1 part Rheology regulator: 1 part.

[0059] Preparation steps: At 20°C, stir the modified acrylate photosensitive resin and polyurethane acrylate resin at 350 revolutions per minute for 15 minutes to obtain a first mixture; Add the hydrophobic silicone modifier and fluorinated silica powder, and stir with a high-speed mixer at 2500 revolutions per minute for 20 minutes to obtain a second mixture; Add polyethylene glycol dimethacrylate, rheology regulator, ultraviolet absorber and styrene-butadiene block copolymer, and stir at 30°C for 10 minutes to obtain a third mixture; In a light-shielded state, add 2-hydroxy-2-methyl-1-phenylpropanone, and stir statically for 6 minutes to obtain a fourth mixture; Defoam under vacuum conditions (-0.1 MPa) for 18 minutes and filter through an 80-mesh sieve to obtain a low-adhesion and high-performance 3D printing polymer composite material.

[0060] Comparative Example 1: Compared with Example 1, the difference is that the modified acrylate photosensitive resin is not added, and the rest of the formula and manufacturing process are the same.

[0061] Comparative Example 2: Compared with Example 1, the difference is that the hydrophobic silicone modifier is not added, and the rest of the formula and manufacturing process are the same.

[0062] Comparative Example 3: Compared with Example 2, the difference lies in that styrene-butadiene block copolymer is not added, and the remaining formulations and manufacturing processes are the same.

[0063] Comparative Example 4: Compared with Example 3, the difference lies in that vacuum degassing is not carried out, and it is used directly after filtration, and the remaining formulations and manufacturing processes are the same.

[0064] Experiment 1: Steps: Sample preparation: According to the formulations and manufacturing processes of Example 1 and Comparative Example 1, 3 standard flat samples were printed and manufactured respectively. The sample size is uniformly 40mm×40mm×1mm, and the DLP photocuring printing method is adopted. The printing parameters are uniformly set as: layer thickness 0.05mm, first layer exposure time 30 seconds, and the remaining layers are 3 seconds. The printing environment temperature is controlled at 24±1°C. The printing platforms are all made of anodized aluminum and are wiped clean with ethanol before use.

[0065] Post-treatment after forming: After the samples are printed, they are naturally cooled for 10 minutes without cleaning, pre-peeling or artificial interference, and the sample state is kept consistent. All samples are stored at room temperature without ultraviolet secondary curing treatment.

[0066] Peeling force test: Fix the printing platform at the bottom clamping position of the peeling test device.

[0067] Use a digital display push-pull force gauge (model: SHP-50N, accuracy ±0.01N) to perform pulling perpendicular to the platform surface, keep the direction of the applied force perpendicular to the contact surface of the sample (90° angle), and pull evenly to avoid violent impact; Record the maximum instantaneous peeling force value (unit: N) before the sample is completely peeled; Each group of samples is independently tested 3 times, and the single original data is recorded; If abnormal conditions such as corner cracking or overall deformation occur during the peeling of the sample, the test status of this time needs to be noted.

[0068] The experimental results are shown in Table 1: Table 1: Data table of the demolding peeling force test of the samples in Example 1 and Comparative Example 1 Sample group Peeling force value Remarks Example 1-1 2.41 —— Example 1-2 2.28 —— Example 1-3 2.67 —— Comparative example 1-1 6.36 Corner warping during peeling Comparative example 1-2 5.84 Slight tearing marks Comparative example 1-3 6.59 Cracking sound during peeling process The modified acrylate used in the example has certain dispersibility and interfacial regulation ability. During the photocuring process, it can form a synergistic effect with the hydrophobic components in the system, reduce the interfacial bonding strength, and make the printed parts easier to detach from the platform after forming. This regulatory effect does not depend on additional coatings or complex structures, but originates from the network design of the material itself.

[0069] As can be seen from the data, the peel strength of Comparative Example 1 is much higher than that of Example 1, and problems such as breakage occur. This shows that after the lack of the modified monomer, the cross-linked layer formed by the curing of the material is more rigid, resulting in a strong bite between the platform and the material, making peeling difficult and even damaging the body of the printed part.

[0070] In terms of structure, the hydroxyl functional group in the modified acrylate helps to form a certain flexible adjustment region before curing. This structure does not significantly reduce the material strength, but can make the stress more evenly distributed on the platform contact surface, thus alleviating the risk of local tearing. In contrast, the unmodified system is more likely to form a rigid bond, increasing the demolding resistance and affecting the integrity of the platform and the bottom layer structure.

[0071] Experiment 2: Steps: Sample preparation: According to the formulations and manufacturing processes of Example 1 and Comparative Example 2, three standard flat specimens were printed and manufactured respectively. The size of the specimens was uniformly 40 mm × 40 mm × 1 mm, and the DLP photocuring printing method was used. The printing parameters were uniformly set as follows: layer thickness 0.05 mm, first layer exposure time 30 seconds, and the remaining layers 3 seconds. The printing environment temperature was controlled at 24 ± 1 °C. The printing platforms were all made of anodized aluminum and were wiped clean with ethanol before use.

[0072] Post-forming treatment: After the specimens were printed, they were naturally cooled for 10 minutes without cleaning, pre-peeling or artificial interference, and the state of the specimens was kept consistent. All specimens were stored at room temperature without ultraviolet secondary curing treatment.

[0073] Peel strength test: Fix the printing platform at the bottom clamping position of the peel test device.

[0074] Use a digital display push-pull force gauge (model: SHP-50N, accuracy ±0.01 N) to perform pulling perpendicular to the platform surface, keep the direction of the applied force perpendicular to the contact surface of the specimen (90° angle), and pull at a constant speed to avoid violent impact; Record the maximum instantaneous peel strength value (unit: N) before the specimen is completely peeled; Each group of specimens was independently tested 3 times, and the single original data was recorded; If abnormalities such as corner breakage or overall deformation occur during the peeling of the specimen, the state of this test needs to be noted.

[0075] The experimental results are shown in Table 2: Table 2: Data table of the demolding peel strength test of the specimens of Example 1 and Comparative Example 2 Sample group Peeling force value Remarks Example 1-4 2.41 —— Example 1-5 2.28 —— Example 1-6 2.67 —— Comparative example 2-1 4.95 Slight edge pulling marks Comparative example 2-2 5.12 Slow peeling, slight cracking sound Comparative example 2-3 4.87 —— From the test results, the force required for demolding of the sample without the hydrophobic silicone modifier (Comparative Example 2) was significantly higher than that of Example 1. The average peel force value increased to about 5 N, and slight edge breakage occurred in some samples during pulling, indicating a strong adhesion to the platform.

[0076] In Example 1, a hydrophobic silicone modifier with a low surface energy was added, forming a lubricating interface structure during the curing process, which weakened the physical interlocking between the platform and the bottom resin. This effect does not rely on softening the resin body, but constructs a non-polar and easily separable microenvironment in the interface layer, thereby reducing the overall demolding resistance.

[0077] In summary, the hydrophobic modifier has a practical effect in improving demolding stability and protecting the formed bottom structure. Its presence helps to control the initial adhesion, avoid strong tearing between the platform and the printed part, and provides a good basis for continuous printing.

[0078] Experiment 3: Steps: Sample preparation: According to the formulations and corresponding manufacturing processes of Example 2 and Comparative Example 3, 3 standard flat samples were printed and manufactured respectively. The sample size was uniformly 40 mm × 40 mm × 1 mm, and the DLP photocuring printing method was used. The printing parameters were uniformly set as: layer thickness 0.05 mm, first layer exposure time 30 s, and the remaining layers 3 s. The printing environment temperature was controlled at 24 ± 1 °C. The printing platforms were all made of anodized aluminum and were wiped clean with ethanol before use.

[0079] Post-forming treatment: After the samples were printed, they were naturally cooled for 10 minutes without cleaning, pre-peeling or artificial interference, and the sample state was kept consistent. All samples were stored at room temperature without UV secondary curing treatment.

[0080] Peel force test: Fix the printing platform at the bottom clamping position of the peel test device.

[0081] Use a digital display push-pull force gauge (model: SHP-50N, accuracy ±0.01 N) to perform pulling perpendicular to the platform surface, keep the force application direction perpendicular to the contact surface of the sample (90° angle), and pull at a constant speed to avoid violent impact; Record the maximum instantaneous peel force value (unit: N) before the sample is completely peeled; Each group of samples was independently tested 3 times, and the single original data was recorded; If abnormal conditions such as corner breakage or overall deformation occur during the peeling of the sample, the test status of this time needs to be noted.

[0082] The experimental results are shown in Table 3: Table 3: Test data table of the demolding and peeling force of the samples in Example 2 and Comparative Example 3 The experimental results show that for the samples without styrene-butadiene block copolymer (Comparative Example 3), compared with Example 2, the demolding force is significantly increased, with an average value of about 5.85 N, and there are slight cracks or corner warping during peeling. This indicates that the lack of this copolymer reduces the flexibility and strain recovery ability of the printed parts, resulting in a stronger bond with the platform and more difficult peeling.

[0083] The addition of styrene-butadiene block copolymer helps to improve the elasticity and resilience of the resin. The microphase separation structure formed during the curing process improves the flexibility of the material, avoids excessive rigidity during the demolding process, and thus reduces the adhesion force. In the absence of this copolymer, the resin system shows high rigidity, resulting in a significant increase in the peeling force.

[0084] Therefore, styrene-butadiene block copolymer plays a key role in improving the demolding performance and the toughness of the material. Its application in the composite material can effectively reduce the demolding force and improve the overall reliability and performance of the material.

[0085] Experiment 4: Steps: Sample preparation: According to the formulations of Example 3 and Comparative Example 4 and the same manufacturing process, 3 standard flat samples were printed and manufactured respectively. The sample size is uniformly 40 mm × 40 mm × 1 mm, and the DLP photocuring printing method is used. The printing parameters are set as follows: layer thickness 0.05 mm, first layer exposure time 30 seconds, and the remaining layers 3 seconds. The printing environment temperature is controlled at 24 ± 1 °C, the printing platform is made of anodized aluminum, and it is uniformly cleaned before use.

[0086] Post-forming treatment: After the samples are printed, they are naturally cooled for 10 minutes, without being cleaned or pre-peeled, and remain in their initial state. The samples are stored at room temperature without secondary UV curing.

[0087] Peeling force test: The printing platform is fixed to the base of the test device, and a digital display push-pull force gauge (model: SHP-50N, accuracy ±0.01 N) is used to pull the sample vertically, maintaining a 90° vertical angle, applying force evenly, and avoiding force fluctuations.

[0088] Each sample is tested independently, and the maximum instantaneous peeling force value (unit: N) before it is completely peeled is recorded; if there are abnormal phenomena such as breakage or cracked edges, they are noted.

[0089] The experimental results are shown in Table 4 as follows: Table 4: Test data table of the demolding peel force of the samples in Example 3 and Comparative Example 4 The experimental results show that the peel force required for the demolding of the samples printed with the resin without vacuum degassing treatment (Comparative Example 4) is significantly higher than that of Example 3. The average peel force is above 4.6 N, and bubble imprints or edge cracking appear on the surface of some samples, indicating that the residual gas in the resin has an adverse effect on the demolding process.

[0090] Vacuum degassing treatment can effectively remove the microbubbles in the system, reduce the surface defects caused by gas expansion during the curing process, and help to form a more uniform and dense bottom contact surface. The interface of the non-degassed resin in the comparative example is uneven locally after curing, which is likely to form local mechanical interlocking, resulting in an increase in the peeling resistance and even damage to the samples.

[0091] It can be seen that degassing, as a resin pretreatment process, has practical significance in ensuring the forming quality and stable demolding. Especially under the conditions of high-precision printing or continuous forming, its role is more crucial.

[0092] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A low-adhesion high-performance 3D printing polymer composite material, characterized in that, Comprising the following components in parts by mass: Modified acrylate photosensitive resin: 60 - 75 parts; Polyurethane acrylate resin: 10 - 20 parts; Hydrophobic silicone modifier: 1 - 5 parts; Fluorinated silica powder: 0.5 - 3 parts; Styrene-butadiene block copolymer: 5 - 15 parts; 2-Hydroxy-2-methyl-1-phenylpropanone: 1 - 5 parts; Polyethylene glycol dimethacrylate: 0.5 - 3 parts; Ultraviolet absorber: 0.5 - 2 parts; Rheology regulator: 0.5 - 2 parts.

2. The low-adhesion and high-performance 3D printing polymer composite material according to claim 1, wherein The modified acrylate photosensitive resin is composed of trimethylolpropane triacrylate and 2-hydroxypropyl methacrylate, and the mass ratio of trimethylolpropane triacrylate to poly-2-hydroxypropyl methacrylate is 3:1 - 5:

1.

3. The low-adhesion high-performance 3D printing polymer composite material according to claim 1, wherein The hydrophobic silicone modifier is a copolymer of hydroxy-terminated polydimethylsiloxane and methyl methacrylate, and the mass ratio of hydroxy-terminated polydimethylsiloxane to methyl methacrylate is 3:1 - 5:

1.

4. The low-adhesion high-performance 3D printing polymer composite material according to claim 1, wherein The particle size of the fluorinated silica powder is 50 - 150 nanometers, and the specific surface area is 100 - 200 m 2 / g.

5. The low-adhesion high-performance 3D printing polymer composite material according to claim 1, characterized in that, The styrene-butadiene block copolymer is a copolymer of styrene and butadiene, and the mass ratio of styrene to butadiene is 2:1 - 3:

1.

6. A method for preparing a low-adhesion high-performance 3D printing polymer composite material, which is used to prepare the low-adhesion high-performance 3D printing polymer composite material according to any one of claims 1-5, characterized in that, Including the following steps: S1. Mix the modified acrylate photosensitive resin and the polyurethane acrylate resin evenly to obtain a first mixture; S2. Add the hydrophobic silicone modifier and the fluorinated silica powder to the first mixture, stir and disperse to obtain a second mixture; S3. Add the ultraviolet absorber, polyethylene glycol dimethacrylate, rheology regulator and styrene-butadiene block copolymer to the second mixture, mix evenly to obtain a third mixture; S4. Add 2-hydroxy-2-methyl-1-phenylpropanone to the third mixture under light-shielded conditions, stir evenly to obtain a fourth mixture; S5. Place the fourth mixture under vacuum conditions for defoaming treatment and filter it through a sieve to obtain a low-adhesion high-performance 3D printing polymer composite material.

7. The method for preparing a low-adhesion and high-performance 3D printing polymer composite material according to claim 6, wherein, In step S1, the mixing temperature is 20 - 30°C and the stirring time is 10 - 15 minutes.

8. The preparation method of the low-adhesion and high-performance 3D printing polymer composite material according to claim 6, wherein, In step 2, the stirring and dispersion is carried out by a high-speed disperser at 2000 - 3000 rpm and the stirring time is 15 - 20 minutes.

9. The method for preparing a low-adhesion and high-performance 3D printing polymer composite material according to claim 6, wherein In step S3, the mixing temperature is 25 - 35°C and the time is 10 - 15 minutes; in step S4, the stirring is carried out under light-shielded conditions and the time is 5 - 10 minutes.

10. The preparation method of the low-adhesion and high-performance 3D printing polymer composite material according to claim 6, wherein, In step S5, the vacuum degree of the defoaming treatment is -0.08 to -0.1 MPa, the time is 15 - 20 minutes, and the sieve filtration uses a sieve with 80 - 150 meshes.

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