阅读说明：本技术 一种耐盐雾腐蚀的石墨烯3d打印材料及其制备方法 (Salt-fog-corrosion-resistant graphene 3D printing material and preparation method thereof ) 是由 邢悦 许婧 任志东 杨程 于 2020-11-10 设计创作，主要内容包括：本发明属于石墨烯复合材料制备及应用领域,具体为一种耐盐雾腐蚀的石墨烯3D打印材料及其制备方法。本发明制备并遴选出适宜微观形貌的石墨烯,具体为含氧量在30％-35％之间的氧化石墨烯微片,片层数不大于10层,微观尺寸为100um-500um的占80％、小于100um的占10％、大于500um的占10％,并将氧化石墨烯微片按微观尺度大小在不同工段分批加入。所述特定形貌氧化石墨烯微片呈褶皱状嵌入聚醚醚酮树脂并与高分子链段充分接触,能够增大与树脂基体的有效结合面积,实现较理想的两相界面调控,从而提升复合材料的微观结构稳定性,并赋予了优异的耐盐雾腐蚀性能。本发明所制备的石墨烯3D打印线材具有优异的耐候性、力学强度高、稳定性强、耐盐雾腐蚀性能突出等特点,适用于FDM型3D打印工艺技术,可广泛应用于航空航天、武器装备等服役环境复杂的领域。(The invention belongs to the field of preparation and application of graphene composite materials, and particularly relates to a salt spray corrosion-resistant graphene 3D printing material and a preparation method thereof. Graphene suitable for the microscopic morphology is prepared and selected, specifically graphene oxide micro-sheets with the oxygen content of 30% -35%, the number of the sheets is not more than 10, the microscopic sizes of the graphene oxide micro-sheets are 80% of 100-500 um, less than 10% of 100um and more than 10% of 500um, and the graphene oxide micro-sheets are added in different working sections in batches according to the microscopic sizes. The graphene oxide micro-sheets with the specific morphology are wrinkled, embedded in the polyether-ether-ketone resin and fully contacted with the high-molecular chain segment, so that the effective combination area with the resin matrix can be increased, and ideal two-phase interface regulation and control are realized, thereby improving the microstructure stability of the composite material and endowing the composite material with excellent salt spray corrosion resistance. The graphene 3D printing wire prepared by the invention has the characteristics of excellent weather resistance, high mechanical strength, strong stability, outstanding salt spray corrosion resistance and the like, is suitable for FDM type 3D printing process technology, and can be widely applied to the field of complex service environments such as aerospace, weaponry and the like.)

1. The salt-spray-corrosion-resistant graphene 3D printing material is characterized by comprising the following components in parts by weight:

polyether ether ketone: 100 portions of

Graphene: 0.1 to 12 portions

Lubricant: 0.1 to 3 portions of

Coupling agent: 0.1 to 2 portions of

Other auxiliary agents: 0.1 to 1 portion

The graphene is a graphene oxide microchip, the oxygen content of the graphene oxide microchip is 30% -35%, the number of the sheets is not more than 10, and the microscopic size of the graphene oxide microchip is 80% of 100um-500um, 10% of the graphene oxide microchip is less than 100um, and 10% of the graphene oxide microchip is more than 500 um.

2. The graphene 3D printed material according to claim 1, wherein the graphene oxide contents of different sizes are normally distributed.

3. The graphene 3D printing material of claim 1, wherein the graphene oxides of different sizes are uniformly dispersed in the composite material.

4. The graphene 3D printed material according to claim 1, wherein the graphene oxide micro-sheets are in a corrugated embedded bonding state within the composite material.

5. The graphene 3D printing material as claimed in claim 1, wherein the weight average molecular weight of the polyetheretherketone is 30000-40000g/mol, and the density is 1.24-1.31g/cm³The melt flow rate is 19-22g/10 min.

6. The graphene 3D printing material according to claim 1, wherein the lubricant is one or more of liquid paraffin, ethylene bis stearamide, and butyl stearate.

7. The graphene 3D printing material of claim 1, wherein the coupling agent is one or more of vinyltriethoxysilane, phenyltrimethoxysilane, aluminate coupling agents, and borate coupling agents.

8. A preparation method for preparing the salt-spray-corrosion-resistant graphene 3D printing material of any one of claims 1 to 7, wherein the preparation method comprises the following steps:

(1) drying the components of claim 1, taking the materials in proportion, and fully and uniformly mixing the parts with the microscopic size of less than 100um in the graphene oxide nanoplatelets and other materials by high-speed stirring;

(2) melting and extruding the blend obtained in the step (1) by a double-screw extruder to prepare a composite master batch, wherein the heating temperature of each zone is 360-400 ℃, and the granules are dried for 6-10h at 120 ℃ for later use;

(3) fully and uniformly mixing the composite master batch obtained in the step (2) with all the remaining graphene oxide micro-sheets with the microscopic sizes larger than 100um, extruding and drawing the mixture by a high-temperature resin wire drawing machine, winding the mixture by a disc to collect coiled wires, wherein the wire diameter of the coiled wires is 1.75 +/-0.05 mm, and the heating temperature of each area of the wire drawing machine is 360-380 ℃; and finally, drying and vacuum packaging the wire.

9. The method for preparing the anti-aging graphene 3D printing material according to claim 8, wherein the composite master batch is a cylindrical particle with uniform gray black color, smooth surface, length of 0.3-0.6cm and cross-sectional diameter of 0.2-0.4 cm.

Technical Field

The invention belongs to a graphene composite material preparation technology, and relates to a graphene polyether ether ketone based composite material for 3D printing and a preparation method thereof.

Background

The 3D printing technology, a mould-free forming technology, gets rid of the constraints of space geometry and design process, and can form various complex structures and parts with high manufacturing difficulty in the traditional process. Meanwhile, the technology can also integrally design parts, reduce assembly steps, shorten the manufacturing period, improve the material utilization rate, reduce the maintenance cost, combine topology optimization to realize weight reduction and the like. In addition, the additive manufacturing technology has great advantages in rapid prototyping verification, the time used in the process can be greatly shortened, and rapid trial-manufacturing response is realized. Polymer consumables that can be used for additive manufacturing are important material bases and key materials for the development of additive manufacturing technology, and are bottlenecks that limit the further development of additive manufacturing technology.

At present, in practical engineering application, if parts of equipment such as ships, shipboard aircrafts, various military aircraft and civil aircrafts, amphibious special equipment, various spacecrafts and the like are prepared in a 3D printing mode, the production cost can be greatly reduced, the production time can be shortened, the weight of the equipment can be reduced, and the energy efficiency ratio of the equipment can be improved. However, the equipment is in service in a high salt spray environment for a long time, and 3D printing parts and components need to have good salt spray corrosion resistance to be really applied to various equipment, so that the 3D printing advanced manufacturing technology can be really applied to the field with harsh service environments such as aerospace and the like.

Polyether-ether-ketone (PEEK) is a special engineering plastic with excellent comprehensive performance, has the characteristics of outstanding mechanical properties, high temperature resistance, corrosion resistance and the like, can be used as a 3D printing consumable material to prepare parts in various fields such as aerospace, mechanical manufacturing, electronics and electricians, biomedicine and the like, and has great application potential. Because the practical application of PEEK is limited by the problems of difficult processing and molding, poor compatibility with other fillers and the like, the performance of PEEK is further improved, and the application range of the PEEK is expanded.

Graphene has a unique two-dimensional structure, and extremely excellent mechanical properties and functional characteristics, so that the novel micro-nano reinforcement graphene which is concerned about is used as a material with a special two-dimensional structure to improve the mechanical properties and functional characteristics of a composite material, and further effectively broaden the application range of a polymer matrix.

Chinese patent CN201810266849.1 discloses a graphene rust curing coating with high salt spray resistance and a preparation method thereof, and the method prepares the rust curing coating by preparing nano graphene dispersion liquid and adding various additives to achieve the functions of corrosion resistance and salt spray resistance so as to fix rust and improve the wear resistance, pressure resistance, compactness and impermeability of a coating. The salt-spray corrosion resistant coating used by the method has high requirements on the self adhesive force, film forming property and coating uniformity; and the process technology requirements in the later construction operation are high, such as coating thickness, layer number, substrate type and treatment, shedding, maintenance and the like. Wherein, any link is not processed well, which may cause the phenomena of coating swelling, wrinkle, foaming and the like, and cannot play a role in protection, but rather becomes the extension of corrosion points; and the method uses a large amount of auxiliary agents, and has various process steps.

Disclosure of Invention

The purpose of the invention is: provided are a salt spray corrosion resistant graphene 3D printing material and a preparation method thereof. According to the invention, graphene with a proper morphology is selected as a reinforcing agent, and on the basis of keeping the inherent excellent characteristics of the polyether-ether-ketone resin, the salt spray corrosion resistance of the graphene is obviously improved, so that the problem of poor weather resistance of a composite material 3D printing part is solved, and the engineering application of the 3D printing part in a high salt spray environment is realized. The invention also provides a preparation method of the material, which has the characteristics of green and environment-friendly composite process, simple and safe operation, stable batch production and the like; the prepared wire rod is uniform and stable in wire diameter, and 3D printing of workpieces can be smoothly carried out.

In order to solve the problems, the invention adopts the following technical scheme:

the salt-spray-corrosion-resistant graphene 3D printing material is characterized by comprising the following components in parts by weight:

polyether ether ketone: 100 portions of

Graphene: 0.1 to 12 portions

Lubricant: 0.1 to 3 portions of

Coupling agent: 0.1 to 2 portions of

Other auxiliary agents: 0.1 to 1 portion

The graphene is a graphene oxide microchip, the oxygen content of the graphene oxide microchip is 30% -35%, the number of the sheets is not more than 10, and the microscopic size of the graphene oxide microchip is 80% of 100um-500um, 10% of the graphene oxide microchip is less than 100um, and 10% of the graphene oxide microchip is more than 500 um.

The content of the graphene oxide with different sizes is normally distributed, and the microscopic bonding strength of the graphene and the polyether-ether-ketone resin can be effectively improved, so that the tissue stability of the 3D graphene printing material is improved, and the salt spray corrosion resistance of the 3D graphene printing material is greatly improved.

The graphene oxide with different sizes is uniformly dispersed in the composite material, and the structural performance of the graphene 3D printing material is improved.

The graphene oxide micro-sheets are in a corrugated embedded combination state in the composite material, and can increase the effective combination area with the polyether-ether-ketone resin and form a good two-phase interface, so that the microstructure stability of the composite material is improved, and the salt spray corrosion resistance of the composite material is greatly improved.

Preferably, the weight average molecular weight of the polyether-ether-ketone is 30000-40000g/mol, and the density is 1.24-1.31g/cm³The melt flow rate is (380 ℃/5kg)19-22g/10 min.

Preferably, the lubricant is one or more of liquid paraffin, ethylene bis stearamide and butyl stearate.

Preferably, the coupling agent is one or more of vinyltriethoxysilane, phenyltrimethoxysilane, aluminate coupling agent and borate coupling agent.

The invention also provides a preparation method of the salt spray corrosion resistant graphene 3D printing material, which comprises the following specific steps:

(1) drying the components of claim 1, taking the materials in proportion, and fully and uniformly mixing the parts with the microscopic size of less than 100um in the graphene oxide nanoplatelets and other materials by high-speed stirring;

(2) melting and extruding the blend obtained in the step (1) by a double-screw extruder to obtain a composite master batch, wherein the heating temperature of each zone is 360-400 ℃, and the granules are dried at 120 ℃ for 6-10h for later use, so that the graphene oxide and polyether-ether-ketone two-phase interface in the composite master batch can be fully combined;

(3) fully and uniformly mixing the composite master batch obtained in the step (2) with all the remaining graphene oxide micro-sheets with the microscopic sizes larger than 100um, extruding and drawing the mixture by a high-temperature resin wire drawing machine, winding the mixture by a disc to collect coiled wires, wherein the wire diameter of the coiled wires is 1.75 +/-0.05 mm, and the heating temperature of each area of the wire drawing machine is 360-380 ℃; the heating temperature of the wire drawing machine is lower than that of a double-screw extruder, so that bubbles are prevented from being generated in the wire drawing process; and finally, drying and vacuum packaging the wire.

The graphene 3D printing composite master batch prepared by the preparation method is uniform gray black, has a smooth surface, and is cylindrical particles with the length of 0.3-0.6cm and the section diameter of 0.2-0.4 cm.

The graphene 3D printing wire prepared by the invention has the characteristics of excellent weather resistance, high mechanical strength, strong stability, outstanding salt spray corrosion resistance and the like, is suitable for FDM type 3D printing process technology, and can be widely applied to the field of high-salt spray service environments such as aerospace navigation, weaponry and the like.

The invention provides a salt-spray-corrosion-resistant graphene 3D printing material and a preparation method thereof, and compared with the prior art, the salt-spray-corrosion-resistant graphene 3D printing material has the outstanding characteristics and excellent effects that:

(1) the graphene oxide which is not subjected to size screening has poor compatibility with polyether-ether-ketone, and is easy to form agglomeration in a resin matrix to generate stress points, so that the performance is attenuated. According to the invention, graphene oxide with a proper morphology is selected through a large number of experiments, so that an ideal dispersion phase is formed with the polyether-ether-ketone resin matrix. The invention solves the problem that graphene oxide is easy to agglomerate, and can obviously improve the mechanical property and the salt spray corrosion resistance of the 3D printing wire rod only by doping a small amount.

(2) The graphene 3D printing wire rod disclosed by the invention has obvious salt spray corrosion resistance, the problem of poor environmental tolerance of a composite material 3D printing workpiece is solved, and the service life of the workpiece in a high salt spray environment is obviously prolonged. Compared with the method for achieving the corrosion resistance and salt spray resistance function through the coating in the prior art, the material prepared by the method can be directly used for manufacturing terminal parts, so that the complex coating construction process is avoided, the salt spray corrosion problem of the parts is solved, and the original mechanical property of the resin is greatly improved.

(3) The preparation process breaks the conventional way, and according to the optimized formula, a preparation process adapting to the formula is developed. The graphene oxide nanoplatelets are added in different working sections in batches according to the size of the microscale, so that the large-size nanoplatelets are prevented from being crushed after being mixed for multiple times, the original microscale of the graphene oxide nanoplatelets is kept, the design proportion is achieved, the optimal mixing effect of the two phases on the microscale is finally realized, and the product with good corrosion resistance is obtained. And the preparation process is simple and easy to operate, environment-friendly and pollution-free.

Drawings

Fig. 1 is a ratio statistic of graphene oxide with different microscopic sizes in a graphene 3D printing material;

FIG. 2 is SEM images of graphene oxide screened out from the graphene 3D printing materials in examples 1-6;

fig. 3 is a graph of tensile strength data for typical examples and comparative examples of graphene 3D printed materials;

fig. 4 is a graph of flexural strength data for typical examples and comparative examples of graphene 3D printed materials;

fig. 5 is a graph of impact strength data for typical examples and comparative examples of graphene 3D printing materials.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The polyetherimide resin used in the embodiment of the invention is 550G of high molecular material company Limited, Mitsui, Jilin province, graphene is synthesized by the inventor through a Hummers method and is obtained through screening and purification, and other reagents are conventional raw materials or reagents. Liquid paraffin is conventionally commercially available, CAS No.: 8012-95-1, Shanghai Aladdin Biotechnology Ltd; the vinyltriethoxysilane is available on the market in general, CAS number 78-08-0, Shanghai Nuotai chemical Co., Ltd; glycerol tribenzoate is commercially available conventionally, CAS No. 614-33-5, Wuhanxin Weiwei light chemical Co., Ltd. The twin-screw mixing granulator and the single-screw extrusion wire drawing machine are conventional equipment in the field.

The material was subjected to a neutral salt spray test, the test being carried out according to the GB/T2423.17-2008 standard, using a Yitai 9701 salt water spray test machine. And (3) testing conditions are as follows: the salt spray concentration is 5%, and the pH value of the test solution is 6.9; the spraying value is 1.3ml/h/80cm²And the temperature of the test cabinet is 35 ℃, a supporting and placing mode is adopted, the residence time is 500h, and the temperature of the cleaning water after the test is 22 ℃.

Testing the mechanical properties of the material before and after the salt spray test by using an Instron 5567 model universal material tester and an RESIL 5.5 model pendulum impact tester; wherein, the tensile test is executed according to the national standard GB/T1040.1-2018, the bending test is executed according to the national standard GB/T9341-2008, and the cantilever beam impact test is executed according to the national standard GB/T1843-2008.

Example 1

In an embodiment of the salt-spray corrosion resistant graphene 3D printing material, raw materials for preparing the graphene 3D printing material according to the embodiment are shown in table 1.

The preparation method of the graphene 3D printing material in this embodiment comprises:

(1) drying the components of claim 1, taking the materials in proportion, and fully and uniformly mixing the parts with the microscopic size of less than 100um in the graphene oxide nanoplatelets and other materials by high-speed stirring;

(2) melting and extruding the blend obtained in the step (1) by a double-screw extruder to prepare a composite master batch, wherein the heating temperature of each zone is 365 ℃, 370 ℃, 375 ℃, 380 ℃, 385 ℃, 380 ℃, 375 ℃ and 370 ℃, the interface bonding speed of graphene and polyether-ether-ketone is controlled by strictly controlling the temperature of the materials in a stepped manner and controlling the feeding speed to be 0.6-1.2kg/min, so that the agglomeration caused by too fast bonding is avoided, the structural stability of the product is reduced, and then the granules are dried for 8 hours at 120 ℃ for later use;

(3) fully and uniformly mixing the composite master batch obtained in the step (2) with all the remaining graphene oxide micro-sheets with the microscopic size larger than 100um, extruding and drawing the mixture by a high-temperature resin wire drawing machine, winding the mixture by a disc to collect coiled wires with the wire diameter of 1.75 +/-0.05 mm, and heating the areas of the wire drawing machine at 365 ℃, 370 ℃, 375 ℃, 370 ℃ and 365 ℃; meanwhile, through gradient temperature control, bubbles are prevented from being generated, and the large-size graphene and the composite master batch are further fused into a final 3D printing material; and finally, drying and vacuum packaging the wire.

Table 1 preparation of graphene 3D printing materials of examples 1 to 6 and comparative examples 1 to 4

Examples 2 to 6

Raw materials for preparing the graphene 3D printing materials described in examples 2 to 6 are described in table 1; the preparation method of the graphene 3D printing material described in embodiments 2 to 6 is the same as that described in embodiment 1.

Comparative examples 1 to 4

Raw materials for preparing the graphene 3D printing materials of comparative examples 1 to 4 are shown in table 1; the preparation method of the graphene 3D printing material described in comparative examples 1 to 4 is the same as that of example 1.

The basic mechanical properties of the graphene 3D printing materials of examples 1 to 6 and comparative examples 1 to 4 were measured, and the results are shown in table 2 below.

Table 2 performance data for graphene 3D printing materials of examples 1-6 and comparative examples 1-4

According to the invention, through a large number of experiments, the microscopic size of the added graphene oxide is optimized, and a batch addition preparation process adaptive to a formula is developed according to the optimized formula; finally, the polyether imide resin forms a perfect dispersed phase with the polyether imide resin matrix. Randomly selecting multiple parts of finally prepared graphene 3D printing material, respectively corroding polyether-ether-ketone by using sulfuric acid for multiple times in a small amount, and screening out graphene oxide micro-sheets. Through observation by a scanning electron microscope and a large amount of statistical analysis, in each sampling material, the graphene oxide micro-sheets are consistent with the designed and put micro-size and proportion, the statistical result is shown in figure 1, and the electron microscope photo is shown in figure 2.

As can be seen from table 2 above and fig. 3-5, the mechanical strength of the graphene 3D printing material of the present invention, such as tensile strength, bending strength, impact strength, etc., is greatly improved compared with pure PEEK resin, and can be respectively improved by 14.6%, 9.6%, and 78.2% at the highest; and after the graphene oxide is added, the composite material can well resist salt spray corrosion and has strong environment tolerance. Particularly, when 1 part of graphene oxide micro-sheet (example 3#) is added, the mechanical strength of stretching, bending, impact and the like is minimally affected by salt spray corrosion, and is respectively reduced by 0.2%, 0.7% and 2.8%, and the original strength is almost maintained; and the mechanical strength of the sample without the graphene oxide is greatly reduced after salt spray corrosion (comparative example 1 #). Through a large number of experiments, after graphene oxide micro-sheets with preferable microscopic sizes (100-500 um accounts for 80%, less than 100um accounts for 10%, and more than 500um accounts for 10%) are added into a resin matrix, the salt spray corrosion process of the composite material is obviously slowed down in examples 1# to 6# compared with the salt spray corrosion process of the composite material in comparative example 1# without the added graphene oxide.

However, when the addition amount of the introduced graphene oxide is too large or the microscale is too large or too small (see comparative examples 2 to 4), self-agglomeration is caused and the dispersion condition of the graphene oxide in a resin matrix is seriously influenced, the two phases cannot realize good interface combination, and the graphene oxide becomes a stress point in the composite material instead, so that the graphene oxide becomes a breakthrough of salt spray corrosion and the mechanical property is greatly reduced.

In summary, through a large number of experiments and data analysis, graphene oxide micro-sheets with the micro-sizes of 100-500 um accounting for 80%, less than 100um accounting for 10% and more than 500um accounting for 10% are preferably selected, the micro-morphology condition that the graphene oxide micro-sheets can be fully contacted with a high molecular chain segment on the micro-layer surface during high-temperature mixing is met, ideal two-phase interface regulation is realized, and the salt spray corrosion resistance of the polyether-ether-ketone resin is improved by adding 0.1-12 parts by weight.

The foregoing is merely a detailed description of the embodiments of the present invention, and some of the conventional techniques are not detailed. The scope of the present invention is not limited thereto, and any changes or substitutions that can be easily made by those skilled in the art within the technical scope of the present invention will be covered by the scope of the present invention. The protection scope of the present invention shall be subject to the protection scope of the claims.