KR102473146B1 - Composition for 3D Printing and Filament for 3D Printer - Google Patents

Abstract

The present invention relates to a composition for 3D printing and a filament for a 3D printer using the same, and more particularly, to a composition for 3D printing that minimizes deformation of an output due to shrinkage during printing and a filament for a 3D printer using the same.
The composition for 3D printing is characterized by comprising acrylonitrile-butadiene-styrene (ABS) and polymethyl methacrylate (PMMA).
The filament for a 3D printer according to the present invention is useful for 3D printing because it can minimize deformation of the output due to shrinkage during printing.

Description

Composition for 3D printing and filament for 3D printer using the same {Composition for 3D Printing and Filament for 3D Printer}

The present invention relates to a composition for 3D printing and a filament for a 3D printer using the same, and more particularly, to a composition for 3D printing that minimizes deformation of an output due to shrinkage during printing and a filament for a 3D printer using the same.

A 3D (3-Dimension) printer is a device that produces a real three-dimensional shape based on an input three-dimensional drawing, just like printing typefaces or pictures. Recently, 3D printing technology has become quite a hot issue, and is expanding to automobile, medical, art, and education fields, and is widely used for making various models. The principles of 3D printers can be divided into cutting type and stacking type, and most of the 3D printers actually applied are stacked type with no material loss.

There are about 20 methods using the layered principle, but the most used methods are SLA (Stereo Lithography Apparatus), FDM (Fused Deposition Modeling), FFF (Fused Filament Fabrication), and SLS (Selective Laser Sintering) methods. .

In the case of SLA, it is a method of modeling by projecting a laser beam into a water tank containing a photocurable resin in a liquid state, and an epoxy-type photopolymer, which is a photocurable resin, is mainly used. On the other hand, FDM (or FFF), which is a method in which the input filament-like material is ejected in a molten state from the nozzle of a printer moving in Z, Y, and Z axes, and is shaped in three dimensions, uses thermoplastic plastic as the main material. On the other hand, SLS implements 3D printing by selectively sintering a water tank containing powdered materials such as metal, plastic, and ceramic powder.

Among the three methods, the FDM method, in which thermoplastics are manufactured in the form of filaments and used, is the most widely popular because the price of a 3D printer is relatively low and the printing speed is faster than other methods. In the FDM method, polylactic acid (PLA), ABS (Acrylonitrile Butadiene Styrene), HDPE, polycarbonate ( Hard materials such as polycarbonate (PC) and flexible materials such as thermoplastic elastomers are used.

In particular, in the case of acrylonitrile-butadiene-styrene (hereinafter: ABS), it is widely used as a general injection and extrusion molding material, and at the same time, it is in the spotlight as a material for extrusion-type 3D printers. However, in the case of general ABS, it is easy to manufacture with a 3D printer filament, but when printing a 3D sculpture using it, the object falls from the 3D printer bed due to dimensional deformation, or the bottom of the object is deformed, causing the bottom of each corner to be rolled up. occurs.

In order to solve this problem, a method of controlling the content of the styrene-based or rubber phase in the ABS molecular structure has been studied.

Korean Patent Registration No. 1860388 discloses 70 to 95 parts by weight of ABS (Acrylonitrile butadienestyrene) resin based on 100 parts by weight of the total composition; And an ABS composition for a 3D printer filament comprising 5 to 30 parts by weight of a thermoplastic elastomer, wherein the thermoplastic elastomer is a thermoplastic urethane-based copolymer (TPU) and a thermoplastic styrenic copolymer (TPE-S) in a ratio of 90 to 93: 7 to 10 An ABS composition for 3D printer filaments, characterized in that it is a mixture of TPU and TPE-S mixed at a weight percent or 7 to 10: 90 to 93 weight percent, is disclosed, and Korean Patent Registration No. 1689304 discloses a thermoplastic amorphous resin mixture 100 It consists of 10 to 25 parts by weight of a thermoplastic crystalline resin mixture and 10 to 25 parts by weight of a thermoplastic amorphous resin mixture, 100 parts by weight of a general-purpose polystyrene resin, 60 to 90 parts by weight of a high-impact polystyrene resin, and 25 to 50 parts by weight of an acrylonitrile butadiene styrene copolymer. Disclosed is a filament composition for a 3D printer, characterized in that it consists of parts by weight.

However, they did not obtain a satisfactory effect in minimizing shrinkage during printing.

Accordingly, the present inventors have made efforts to solve the above problems, and as a result, it was confirmed that dimensional deformation due to shrinkage can be minimized when polymethyl methacrylate (PMMA) is used together with acrylonitrile-butadiene-styrene (ABS), , which led to completion of the present invention.

An object of the present invention is to provide a composition for 3D printing capable of minimizing dimensional deformation due to shrinkage during printing and a filament for a 3D printer prepared by extruding the same.

In order to achieve the above object, the present invention provides a composition for 3D printing comprising acrylonitrile-butadiene-styrene (ABS) and polymethyl methacrylate (PMMA).

In the present invention, the polymethyl methacrylate (PMMA) is characterized in that it is included in 10 to 30 parts by weight based on 100 parts by weight of acrylonitrile-butadiene-styrene (ABS).

In the present invention, the acrylonitrile-butadiene-styrene (ABS) is (a) a blend type (Butadiene Rubber, BR) or (b) styrene-butadiene rubber (SBR) It is characterized in that it is a graft type or graft-blend type obtained by graft copolymerization of styrene and acrylonitrile in the presence of latex.

In the present invention, the acrylonitrile-butadiene-styrene (ABS) is a graft-blend type, characterized in that the rubber content is 10 to 50% by weight.

In the present invention, the acrylonitrile-butadiene-styrene (ABS) is characterized in that the melt flow rate (MFR) is 37g / 10min to 50g / 10min according to ASTM D 1238 standard.

In the present invention, the polymethyl methacrylate (PMMA) is characterized in that it is a thermoplastic resin prepared by free radical polymerization using methyl methacrylate as a monomer.

The present invention also provides a filament for a 3D printer prepared by extruding the composition for 3D printing.

In the present invention, the filament for the 3D printer is characterized in that the diameter is 0.8 ~ 4.0 mm.

In the present invention, the filament for the 3D printer is characterized in that the average shrinkage rate of each corner is 5% or less when output as a sculpture (60 mm wide, 60 mm long, 20 mm high).

The filament for a 3D printer according to the present invention is useful for 3D printing because it can minimize deformation of the output due to shrinkage during printing.

1 is a view showing the ASTM D638 output direction for a tensile strength test of a 3D printed specimen manufactured according to an embodiment of the present invention.
2 is a three-dimensional scanning photograph of a sculpture manufactured according to Comparative Example 1 of the present invention.
3 is a three-dimensional scanning photograph of a sculpture manufactured according to an embodiment of the present invention.

In the present invention, it was confirmed that dimensional deformation due to shrinkage during 3D printing can be minimized when polymethyl methacrylate (PMMA) is used together with acrylonitrile-butadiene-styrene (ABS).

In the present invention, a filament for a 3D printer was prepared by extruding a composition containing acrylonitrile-butadiene-styrene (ABS) and polymethyl methacrylate (PMMA), and then it was output as a sculpture and a specimen in the 3D printer. . As a result, it was confirmed that the tensile strength of the manufactured specimen and the shrinkage rate of the edge of the sculpture were excellent, so that the dimensional deformation due to shrinkage during 3D printing was small.

Accordingly, in one aspect, the present invention relates to a composition for 3D printing comprising acrylonitrile-butadiene-styrene (ABS) and polymethyl methacrylate (PMMA).

In the present invention, the acrylonitrile-butadiene-styrene (ABS) is (a) a blend type (Butadiene) by a polymer blend of a styrene-acrylonitrile copolymer and acrylonitrile-butadiene rubber (NBR) Rubber, BR) or (b) styrene-butadiene rubber (SBR) Graft type or graft-blend type obtained by graft copolymerization of styrene and acrylonitrile in the coexistence of latex can be used, but the rubber content is 10 It is preferred to use a graft-blend type that is -50% by weight.

When the rubber content in the acrylonitrile-butadiene-styrene (ABS) is less than 10% by weight, the impact strength is low, resulting in brittleness during filament production, and when it exceeds 50% by weight, the extrusion type is reduced due to a decrease in flow index. 3D printing can be disadvantageous.

Therefore, the melt flow rate (MFR) of the acrylonitrile-butadiene-styrene (ABS) is preferably 37g/10min to 50g/10min according to ASTM D 1238 standard.

In the present invention, the polymethyl methacrylate (PMMA) is a thermoplastic resin prepared by free radical polymerization using methyl methacrylate as a monomer, and is a homopolymer or copolymer of methyl methacrylate (MMA) or a mixture thereof means

Polymethyl methacrylate (PMMA) of the present invention is a homo or copolymer of methyl methacrylate (MMA) is 70% by weight or more, preferably 80% by weight or more, advantageously 90% by weight or more, more advantageously It may contain 95% by weight or more of methyl methacrylate.

In the composition for 3D printing of the present invention, the polymethyl methacrylate (PMMA) is preferably included in an amount of 10 to 30 parts by weight based on 100 parts by weight of acrylonitrile-butadiene-styrene (ABS).

If the polymethyl methacrylate (PMMA) is less than 10 parts by weight, there is a problem that the bottom of the 3D sculpture is deformed after printing due to shrinkage of ABS, and if it exceeds 30 parts by weight, the adhesive strength between layers in the Z direction of the 3D sculpture is lowered. A problem in which the strength of the sculpture is weakened may occur.

When the composition for 3D printing of the present invention is extruded in a single screw extruder and then cooled, a filament for a 3D printer can be prepared. more preferable

If the diameter of the filament is less than 0.8 mm, the printer device may not easily supply the filament because it is too thin, or the filament may not be discharged because the filament is pressed, or the printing speed may be slow. In addition, when the filament diameter exceeds 4 mm, the solidification speed is slow, it is difficult to melt the filament, and the precision of the printed object may decrease.

Since the filament for a 3D printer according to the present invention contains polymethyl methacrylate (PMMA) that improves the shrinkage rate of acrylonitrile-butadiene-styrene (ABS), the sculpture (60 mm wide, 60 mm long, 20 mm high) When output as , the average of each corner shrinkage can be 5% or less.

In addition, the filament for 3D printer according to the present invention is 37.5 based on the tensile strength (40MPa) of the specimen produced through injection molding when the dumbbell-shaped specimen of ASTM D 638 V type is output by the method (c) in Figure 1 Corresponds to %~50% (15~20MPa), and has good tensile strength.

[Example]

Hereinafter, the present invention will be described in more detail through examples. These examples are only for illustrating the present invention, and it will be apparent to those skilled in the art that the scope of the present invention is not to be construed as being limited by these examples.

Examples 1 to 3 and Comparative Examples 1 to 4: Manufacturing filaments for 3D printers

After extruding the composition containing acrylonitrile-butadiene-styrene (ABS) and polymethyl methacrylate (PMMA) in Table 1 with a single screw extruder (screw diameter 30 mm, screw length 105 mm), length It was cooled in a 3 m cooling water bath and wound up to prepare a filament for a 3D printer having a diameter of 1.75 mm.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 A 100 100 100 100 100 0 0 A' 0 0 0 0 0 100 100 B 10 30 25 0 40 25 0

A: ABS LG Chem HF 380 (Melt Flow Index: 45g/10min (at.220℃/10kg))

A': ABS Styrolution GP35 (Melt Flow Index: 35g/10min (at.220℃/10kg))

B: PMMA: LG MMA IF870S

Experimental example: 3D printing sculpture and specimen manufacturing using filament for 3D printer

Using the 3D printer filaments of Examples 1 to 3 and Comparative Examples 1 to 4, a 3D printer (Opencreator ALMOND) was printed as a sculpture (60 mm in width, 60 mm in length, 20 mm in height) for deformation evaluation, and then the corner Shrinkage was confirmed and the results are shown in Table 2. The sculpture was printed under the following conditions: printing speed: 70 mm/sec to 50 mm/sec, nozzle temperature: 245° C., nozzle diameter: 0.4 mm, bed temperature: 80° C., and internal filling: 100%.

For the corner shrinkage, after leaving the printed sculpture for 24 hours, each corner was measured with a vernier caliper, and the actual height was converted into a percentage compared to the height of 20 mm.

In addition, in order to confirm the tensile strength, a dumbbell-shaped specimen of ASTM D 638 V type was output by the method (c) in Figure 1, and a specimen of the same standard was manufactured through injection molding. If the tensile strength in the Z direction exceeds 37.5% (15MPa) compared to the tensile strength (40MPa) of the tensile specimen manufactured through injection molding, it is evaluated as good, and if it is less than 37.5% (15MPa), it is evaluated as insufficient, and the results are shown in Table 2. was

In addition, according to the melt flow rate (MFR) of acrylonitrile-butadiene-styrene (ABS), when the printing speed is 70 mm / sec, when the specimen or sculpture is excellently output, the printing speed is good, when the printing speed is 50 mm / sec, the specimen or When the sculpture was output excellently, the printing speed was judged to be insufficient, and the results are shown in Table 2.

division Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Z direction
The tensile strength 18 MPa
Good 16 MPa
Good 17 MPa
Good 19 MPa
Good 13 MPa
Inadequate 16 MPa
Good 17 MPa
Good output
edge
shrinkage rate 4.8%
Good 4.0%
Good 4.3%
Good 6%
Inadequate 3%
Good 4.3%
Good 7%
Inadequate printing speed Good Good Good Good Good Inadequate Inadequate

From Table 2, the Z-direction tensile strength of the specimens of Examples 1 to 3 printed with a filament containing 10 to 30 parts by weight of PMMA with respect to 100 parts by weight of ABS (A) having a melt flow index of 45 g / 10 min or more, the shrinkage rate of the edges of the output and printing All speeds were found to be good.

On the other hand, Comparative Example 1 without PMMA had good tensile strength and printing speed in the Z direction, but the output edge shrinkage was insufficient, and Comparative Example 2, which contained an excessive amount of PMMA, had good output edge shrinkage and printing speed, but Z-direction tensile Strength was found to be insufficient.

In addition, Comparative Example 3 printed with a filament containing 25 parts by weight of PMMA using ABS (A′) having a melt flow index of 35 g/10 min or less has good tensile strength in the Z direction and shrinkage rate of the edges of the output, but the printing speed is found to be insufficient. It became.

Finally, Comparative Example 4 using only ABS (A') having a melt flow index of 35 g / 10 min or less and not including PMMA had good tensile strength in the Z direction, but it was confirmed that the output corner shrinkage and printing speed were insufficient.

Having described specific parts of the present invention in detail above, it will be clear to those skilled in the art that these specific descriptions are only preferred embodiments, and the scope of the present invention is not limited thereby. will be. Accordingly, the substantial scope of the invention will be defined by the appended claims and their equivalents.

Claims (9)

Includes acrylonitrile-butadiene-styrene (ABS) and polymethylmethacrylate (PMMA),
The acrylonitrile-butadiene-styrene (ABS) is a graft type or a graft-blend type obtained by graft copolymerization of styrene and acrylonitrile in the presence of styrene-butadiene rubber (SBR) latex,
The acrylonitrile-butadiene-styrene (ABS) has a melt flow rate (MFR) of 37g/10min to 50g/10min according to ASTM D 1238, a composition for 3D printing.
The composition for 3D printing according to claim 1, wherein the polymethyl methacrylate (PMMA) is contained in an amount of 10 to 30 parts by weight based on 100 parts by weight of acrylonitrile-butadiene-styrene (ABS).
delete The composition for 3D printing according to claim 1, wherein the acrylonitrile-butadiene-styrene (ABS) is a graft-blended type and has a rubber content of 10 to 50% by weight.
delete The composition for 3D printing according to claim 1, wherein the polymethyl methacrylate (PMMA) is a thermoplastic resin prepared by free radical polymerization using methyl methacrylate as a monomer.
A filament for a 3D printer prepared by extruding the composition for 3D printing of any one of claims 1, 2, 4, and 6.
The filament for a 3D printer according to claim 7, wherein the filament for a 3D printer has a diameter of 0.8 to 4.0 mm.
The filament for a 3D printer according to claim 7, wherein the filament for a 3D printer has an average shrinkage rate of 5% or less when output as a sculpture (60 mm in width, 60 mm in length, and 20 mm in height).

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