Graphene oxide modified nylon material for three-dimensional printing and preparation method and application thereof

Abstract

The present invention belongs to the technical field of polymer materials, and discloses a graphene oxide modified nylon material for three-dimensional printing, a preparation method and an application thereof. The raw materials of the graphene oxide modified nylon material for three-dimensional printing include nylon 6, graphene oxide, calcium carbonate, a thermal stabilizer and a silane coupling agent; the present invention utilizes that the surface of graphene oxide contains tiny holes, and a large number of oxygen-containing functional groups exist at the edges of these holes and the edges of the sheets, and the oxygen-containing functional groups give graphene oxide new properties, such as hydrophilicity, dispersibility, compatibility with polymers, etc., and at the same time utilizes the carboxyl groups on the graphene oxide to react with the terminal amino groups of the nylon 6 molecular chain to enhance the interface interaction between the graphene oxide and the nylon 6 matrix, and enhance the dispersibility of the graphene oxide in the nylon 6 matrix. In addition, calcium carbonate and graphene oxide work together to produce a uniform network structure in the nylon 6 matrix, which is conducive to the formation of micropores, thereby having good moisture absorption and warmth retention properties.

Description

Technical Field

[0001] The present invention belongs to the technical field of polymer materials, and in particular relates to a graphene oxide modified nylon material for three-dimensional printing, a preparation method and an application thereof. Background Art

[0002] Three-dimensional printing (3DP), originated in the 1980s, is a technology that uses discrete materials (liquid, powder, silk, sheet, plate, etc.) based on digital model files to create objects of arbitrary complex shapes by layer-by-layer accumulation. Its working principle is to first build a model through computer modeling software, or scan an existing object, and then divide the built three-dimensional model into layer-by-layer cross-sections, i.e. slices, and then guide the printer to use the printing material to print layer by layer, and stack them layer by layer to form a three-dimensional finished product.

[0003] Commonly used printing materials include polylactic acid (PLA), acrylonitrile-butadiene-styrene copolymer (ABS), polycarbonate polyester (PC), nylon (PA), etc. Taking nylon materials as an example, nylon materials are widely used in the textile field because of their light weight, good mechanical properties, good chemical resistance, simple processing technology and relatively low cost. However, textiles printed by 3D printing using a single nylon 6 can no longer meet the market's diverse functional needs for textiles. At present, graphene-based composite nylon materials use graphene to modify nylon materials, so that the composite materials have the characteristics of high strength, light weight and good flexibility. Graphene-based composite nylon materials mainly solve the strength problem of the product, but due to the poor hydrophilicity and dispersibility of graphene itself, and poor compatibility with nylon polymers, textiles obtained by 3D printing using graphene-based composite nylon materials cannot meet the functional requirements of warmth and moisture absorption. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the above-mentioned prior art. To this end, the present invention provides a graphene oxide modified nylon material for three-dimensional printing. The textiles obtained by 3D printing using the graphene oxide modified nylon material for three-dimensional printing of the present invention have good warmth retention and moisture absorption properties.

[0005] A first aspect of the present invention provides a graphene oxide modified nylon material for three-dimensional printing. The raw materials for preparing the graphene oxide modified nylon material for three-dimensional printing include: nylon 6, graphene oxide, calcium carbonate, a thermal stabilizer and a silane coupling agent.

[0006] Preferably, the addition amount of the graphene oxide in the graphene oxide-modified nylon material for three-dimensional printing is 2-8wt%.

[0007] Preferably, the mass ratio of the calcium carbonate to the silane coupling agent is 40-50:1.

[0008] Preferably, the molecular weight of the nylon 6 is 10000-15000, and the viscosity at room temperature is 2.5-3.

[0009] Preferably, the graphene oxide is powdered graphene oxide with a size of 2500-3000 mesh.

[0010] Preferably, the heat stabilizer includes at least one of zinc stearate, zinc distearate, and trihydroxyethyl isocyanurate.

[0011] Preferably, the silane coupling agent includes at least one of γ-aminopropyltriethoxysilane (KH-550) and γ-aminopropyltrimethoxysilane.

[0012] The second aspect of the present invention provides a method for preparing the graphene oxide modified nylon material for three-dimensional printing according to the present invention, comprising the following steps:

[0013] The nylon 6, the graphene oxide, the calcium carbonate, the heat stabilizer and the silane coupling agent are mixed and melt-extruded to obtain the graphene oxide-modified nylon material for three-dimensional printing.

[0014] Preferably, the method for preparing the graphene oxide modified nylon material for three-dimensional printing according to the present invention comprises the following steps:

[0015] The calcium carbonate and the silane coupling agent are added to a solvent, stirred, and then the solvent is removed and dried to obtain pretreated calcium carbonate;

[0016] The pretreated calcium carbonate and the graphene oxide are mixed and stirred for 5-10 minutes, and then the nylon 6 is added, mixed and stirred for 5-10 minutes, and then melt-extruded to obtain the graphene oxide-modified nylon material for three-dimensional printing.

[0017] It should be noted that the present invention pre-treats calcium carbonate with a silane coupling agent, and the surface-treated calcium carbonate has a strong interfacial force with the nylon matrix and forms a good dispersion effect, so that the graphene oxide can be more evenly dispersed in the nylon 6 material. However, the calcium carbonate that has not been pre-treated with a silane coupling agent fails to form a good interfacial effect with the nylon matrix and easily fails to achieve the effect of dispersing graphene oxide.

[0018] Preferably, the temperature of the melt extrusion is 185-220°C.

[0019] Preferably, the melt extrusion adopts a twin-screw extruder; the temperature of each section of the extruder is 185-220° C.; and the screw speed is 60-80 r / min.

[0020] Preferably, the solvent is 95 wt% ethanol solution.

[0021] Preferably, the stirring time is 1-3 hours.

[0022] Preferably, the drying process specifically includes: drying in a vacuum drying oven at 80-100° C. until the moisture content of the material is less than 0.5wt%.

[0023] Preferably, the water content of the pretreated calcium carbonate is lower than 0.5wt%. The present invention can improve the moisture absorption and warmth retention properties of the graphene oxide modified nylon material for three-dimensional printing by limiting the water content of the pretreated calcium carbonate to lower than 0.5wt%.

[0024] The third aspect of the present invention provides the use of the graphene oxide modified nylon material for three-dimensional printing according to the present invention in three-dimensional printing.

[0025] A fourth aspect of the present invention provides a textile, which is prepared by three-dimensional printing of the graphene oxide-modified nylon material for three-dimensional printing described in the present invention.

[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0027] (1) The graphene oxide modified nylon material for three-dimensional printing of the present invention is added with graphene oxide and calcium carbonate, wherein graphene oxide is a derivative of graphene surface functionalization. Different from the complete single atomic layer on the graphene surface, the surface of graphene oxide contains some tiny holes, and a large number of oxygen-containing functional groups (such as hydroxyl, carboxyl, epoxy, etc.) exist at the edges of these holes and the edges of the sheets. The oxygen-containing functional groups give graphene oxide new properties, such as hydrophilicity, dispersibility, and compatibility with polymers, thereby solving the problem of poor hydrophilicity of nylon 6. At the same time, the carboxyl groups on the graphene oxide react with the terminal amino groups of the nylon 6 molecular chain to enhance the interface interaction between the graphene oxide and the nylon 6 matrix, thereby enhancing the dispersibility of the graphene oxide in the nylon 6 matrix. In addition, the calcium carbonate and graphene oxide work together to produce a uniform network structure in the nylon 6 matrix, which is conducive to the formation of micropores. Under the combined effect of these factors, the graphene oxide modified nylon material for three-dimensional printing of the present invention has good moisture absorption and thermal insulation properties.

[0028] (2) The preparation method of the graphene oxide modified nylon material for three-dimensional printing of the present invention is simple and easy, the raw materials are easily available and the cost is low, and large-scale industrial production is possible. DETAILED DESCRIPTION

[0029] In order to make the technical scheme of the present invention more clearly understood by those skilled in the art, the following embodiments are listed for illustration. It should be pointed out that the following embodiments do not limit the protection scope of the present invention.

[0030] Unless otherwise specified, the raw materials, reagents and devices used in the following examples can be obtained from conventional commercial sources or by existing known methods.

[0031] Normal temperature in the present invention refers to 10-30°C.

[0032] Example 1

[0033] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 2% of graphene oxide, 10% of calcium carbonate, 7.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0034] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0035] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0036] Calcium carbonate and γ-aminopropyltriethoxysilane are added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol is removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material is less than 0.5 wt% to obtain pretreated calcium carbonate;

[0037] The pretreated calcium carbonate and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0038] Example 2

[0039] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 4% of graphene oxide, 10% of calcium carbonate, 5.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0040] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0041] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0042] Calcium carbonate and γ-aminopropyltriethoxysilane are added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol is removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material is less than 0.5 wt% to obtain pretreated calcium carbonate;

[0043] The pretreated calcium carbonate and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0044] Example 3

[0045] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 6% of graphene oxide, 10% of calcium carbonate, 3.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0046] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0047] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0048] Calcium carbonate and γ-aminopropyltriethoxysilane are added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol is removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material is less than 0.5 wt% to obtain pretreated calcium carbonate;

[0049] The pretreated calcium carbonate and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0050] Example 4

[0051] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 8% of graphene oxide, 10% of calcium carbonate, 1.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0052] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0053] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0054] Calcium carbonate and γ-aminopropyltriethoxysilane are added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol is removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material is less than 0.5 wt% to obtain pretreated calcium carbonate;

[0055] The pretreated calcium carbonate and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0056] Comparative Example 1 (the difference from Example 3 is that no calcium carbonate is added)

[0057] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 6% of graphene oxide, 13.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0058] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0059] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0060] Graphene oxide, nylon 6, zinc stearate and γ-aminopropyltriethoxysilane are mixed and stirred for 5 minutes to obtain a mixture, and then the mixture is melt-extruded and pelletized using a twin-screw extruder to obtain a graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder are 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, 220°C, and the screw speed is 80r / min.

[0061] Comparative Example 2 (the difference from Example 3 is that graphene is used instead of graphene oxide)

[0062] A graphene-modified nylon material consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 6% of graphene, 10% of calcium carbonate, 3.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0063] Among them, the molecular weight of nylon 6 is 10,000, and the viscosity at room temperature is 2.5; the graphene is powdered graphene with a specification of 2500 mesh.

[0064] The preparation method of the graphene-modified nylon material comprises the following steps:

[0065] Calcium carbonate and γ-aminopropyltriethoxysilane are added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol is removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material is less than 0.5 wt% to obtain pretreated calcium carbonate;

[0066] The pretreated calcium carbonate and graphene were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain a graphene-modified nylon material; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0067] Comparative Example 3 (the difference from Example 3 is that calcium carbonate is not pretreated)

[0068] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 6% of graphene oxide, 10% of calcium carbonate, 3.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0069] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0070] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0071] Calcium carbonate, γ-aminopropyltriethoxysilane and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain a graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0072] Comparative Example 4 (the difference from Example 3 is that the moisture content of the pretreated calcium carbonate is higher than 0.5wt%)

[0073] A graphene oxide modified nylon material for three-dimensional printing consists of the following raw materials, measured by mass percentage: 80% of nylon 6, 6% of graphene oxide, 10% of calcium carbonate, 3.75% of zinc stearate and 0.25% of gamma-aminopropyltriethoxysilane.

[0074] Among them, the molecular weight of nylon 6 is 10000, and the viscosity at room temperature is 2.5; the graphene oxide is powdered graphene oxide with a specification of 2500 mesh.

[0075] The method for preparing the graphene oxide modified nylon material for three-dimensional printing comprises the following steps:

[0076] Calcium carbonate and γ-aminopropyltriethoxysilane were added to a 95 wt% ethanol solution, stirred for 1 hour, and then the ethanol was removed by rotary evaporation, and then dried in a vacuum drying oven at 80° C. until the moisture content of the material was 1 wt%, to obtain pretreated calcium carbonate;

[0077] The pretreated calcium carbonate and graphene oxide were mixed and stirred for 5 minutes, and nylon 6 was added and the mixing and stirring was continued for 5 minutes to obtain a mixture, and then the mixture was melt-extruded and pelletized using a twin-screw extruder to obtain graphene oxide-modified nylon material for three-dimensional printing; wherein the barrel temperatures of the extruder were 185°C, 200°C, 217°C, 230°C, 226°C, 223°C, and 220°C, respectively, and the screw speed was 80r / min.

[0078] Performance Testing

[0079] 1. Thermal insulation performance test: The materials prepared in Examples 1-4 and Comparative Examples 1-4 were respectively printed into textile samples of 100 mm × 100 mm × 10 mm using a 3D printer. According to GB / T 11048-2018 "Determination of thermal resistance and moisture resistance of textiles under steady-state conditions for physiological comfort", the thermal insulation performance of the samples was tested on a YG 606D flat-plate fabric insulation instrument. The thermal conductivity W / (m·K), clo value (clo) and thermal insulation rate (%) of the samples were tested respectively, and the average value was taken after 3 measurements. The results are shown in Table 1.

[0080] Table 1

[0081]

[0082]

[0083] From the thermal insulation test results in Table 1, it can be seen that as the content of added graphene oxide increases, the thermal conductivity of the samples of Examples 1-4 shows a trend of first decreasing and then increasing. When the content of graphene oxide is 6%, the thermal conductivity of the sample is as low as 1.1. Thereafter, as the content of graphene oxide increases, the thermal conductivity of the sample increases accordingly. This is because more graphene oxide may not be evenly distributed in the nylon 6 matrix, which not only fails to reduce the heat transfer performance of the fiber, but also affects the filling effect of the voids in the nylon 6 matrix, thereby causing the thermal conductivity of the sample to show an upward trend.

[0084] The order of thermal conductivity from large to small is: 7#>8#>6#>5#>1#>4#>2#>3#, the larger the thermal conductivity, the worse the thermal insulation performance of the material; the order of Krogh value from large to small is: 3#>2#>4#>1#>5#>6#>8#>7#, the larger the Krogh value, the better the thermal insulation performance, and the more suitable it is for thermal insulation material; the order of thermal insulation rate from large to small is: 3#>4#>2#>1#>5#>6#>8#>7#; it can be seen that Example 3 has the smallest thermal conductivity, the highest thermal insulation rate, and the best thermal insulation performance.

[0085] 2. Hygroscopicity test: According to GB / T 21655.1-2008 "Evaluation of moisture absorption and quick-drying properties of textiles Part 1: Single combination test method", the materials prepared in Examples 1-4 and Comparative Examples 1-4 were respectively printed into textile samples using a 3D printer, and 5 representative samples were cut, each of which had a size of at least 10 cm × 10 cm. The sample should be flat and wrinkle-free. The water absorption rate, drip diffusion time and wicking height of the sample were used to characterize the adsorption capacity of the sample for liquid sweat. The water absorption rate, drip diffusion time and wicking height were tested respectively. The results are shown in Table 2.

[0086] Table 2

[0087]

[0088]

[0089] From the hygroscopicity test results in Table 2, it can be seen that the hygroscopicity indicators of the samples of Examples 1-4 are better than those of Comparative Examples 1-4. This is because the surface of graphene oxide has abundant oxygen-containing functional groups, which can form strong hydrogen bonds with water molecules, thereby improving the hydrophilicity of the material. At the same time, calcium carbonate pretreated with a silane coupling agent can also effectively disperse the distribution of graphene oxide in the nylon 6 matrix, thereby improving the hygroscopicity.

[0090] The preferred embodiments of the present invention are specifically described above, but the invention is not limited to the embodiments. Those skilled in the art may make various equivalent modifications or substitutions without violating the spirit of the invention. These equivalent modifications or substitutions are all included in the scope defined by the claims of this application.

Claims

1. A graphene oxide modified nylon material for three-dimensional printing, characterized in that: The raw materials for preparing the graphene oxide modified nylon material for three-dimensional printing include: nylon 6, graphene oxide, calcium carbonate, a thermal stabilizer and a silane coupling agent; The amount of the graphene oxide added to the graphene oxide modified nylon material for three-dimensional printing is 2-8wt%; The mass percentage of calcium carbonate in the raw material is 10%; The mass ratio of the calcium carbonate to the silane coupling agent is 40-50:1; The graphene oxide modified nylon material for three-dimensional printing is prepared by a preparation method comprising the following steps: Adding the calcium carbonate and the silane coupling agent into a solvent, stirring, removing the solvent, and drying to obtain pretreated calcium carbonate; The pretreated calcium carbonate and the graphene oxide are mixed and stirred for 5-10 minutes, and then the nylon 6 is added, mixed and stirred for 5-10 minutes, and then melt-extruded to obtain the graphene oxide-modified nylon material for three-dimensional printing; The water content of the pretreated calcium carbonate is lower than 0.5 wt %.

2. The graphene oxide modified nylon material for three-dimensional printing according to claim 1, characterized in that: The molecular weight of the nylon 6 is 10000-15000, and the viscosity at room temperature is 2.5-3 Pa·s.

3. The graphene oxide modified nylon material for three-dimensional printing according to claim 1, characterized in that: The graphene oxide is powdered graphene oxide with a specification of 2500-3000 meshes.

4. Application of the graphene oxide modified nylon material for three-dimensional printing according to any one of claims 1 to 3 in three-dimensional printing.

5. A textile, characterized in that: The textile is prepared by three-dimensional printing of the graphene oxide-modified nylon material for three-dimensional printing as described in any one of claims 1 to 3.

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