KR101852921B1 - Menufacturing method for molded article using fiber reinforcerd plastic waste - Google Patents

Abstract

The present invention relates to a method of manufacturing a molded article using waste fiber reinforced plastic. In one embodiment, the method for manufacturing a molded body using the waste fiber reinforced plastic comprises the steps of: pulverizing the waste fiber reinforced plastic to produce a pulverized product; And a step of pressurizing the pulverized product to produce a molded product, wherein the waste fiber reinforced plastic comprises a matrix resin and a fiber filler impregnated in the matrix resin, wherein ultrasonic vibration is applied to the pulverized product at the time of pressing, do.

Description

TECHNICAL FIELD [0001] The present invention relates to a method for manufacturing a molded body using waste fiber reinforced plastic,

The present invention relates to a method of manufacturing a molded article using waste fiber reinforced plastic.

Fiber Reinforced Plastic (FRP) is a composite material formed by combining a reinforcing fiber filler that transmits and supports a load, and a matrix resin for coating effect and maintaining the shape of the main body. Fiber filler reinforced plastic has excellent moldability and mechanical properties of existing plastics and excellent tensile strength of reinforced fiber filler. It has excellent lightweight properties and is suitable for various applications such as aviation, space, ship, automobile, Has been used in the field. Such fiber filler reinforced plastics are produced by a lamination molding method, a filament wanding method, a continuous molding method, and various manufacturing methods are being studied.

Carbon fiber reinforced plastics (CFRP), which is one kind of the fiber filler reinforced plastics, is excellent in light weight, corrosion resistance and mechanical strength and is used in various industrial fields. The carbon fiber filler reinforced plastic is mainly manufactured by using a prepreg base impregnated with a carbon fiber filler. For example, thermosetting prepregs such as so-called unidirectional prepregs formed by impregnating a sheet of carbon fiber filler in one direction with a thermosetting resin are cut and laminated as required, The so-called autoclave molding method in which the resin is cured is easy to obtain CFRP excellent in mechanical characteristics and thermal stability, and is widely employed in applications requiring high performance such as in aerospace applications.

As a method of manufacturing the carbon fiber filler reinforced plastic, there is a resin transfer molding (RTM) method. This is a method in which a carbon fiber filler base material (for example, a base material such as a fabric) that does not contain a resin is placed in a mold, and then a resin is injected and cured. This method has a wide range of shapes of CFRPs that can be molded as compared with the autoclave method, and the time required for molding is also short. Therefore, it is expected that the use of the CFRP in automobile applications, particularly in mass-produced vehicles, will be expanded in the future.

On the other hand, as the production of fiber-reinforced plastics increases, the disposal cost of the used plastics increases and the problem of environmental pollution is increasing. Recently, as the interest in the environment has increased, Research on the technology to recycle plastics is actively being carried out.

However, the regeneration efficiency of such a fiber filler reinforced plastic is very low when the regenerating technology of conventional plastic materials is applied. This is because in the washing process for regeneration, the water penetrates and is absorbed during the washing along the interface between the fibrous filler of the waste fiber filler reinforced plastic and the matrix resin, whereby the physical properties of the molded article after extrusion are generally lowered For example. Therefore, in the current plastic regeneration, only the materials to which the existing recycling technology can be applied are separated and recycled, and the fiber filler reinforced plastic containing the reinforcing fiber filler at a certain level or more is classified as waste, and the waste is disposed of by incineration or incineration It is true.

Until recently, methods of treating waste fiber filler reinforced plastic (FRP) have been attempted mainly by incineration and burial. However, since the waste fiber filler reinforced plastic (FRP) includes a thermosetting material which is not easily thermally softened and burned when heat is applied and is incapable of incineration, it is difficult to achieve the weight loss effect, which is an advantage of incineration during incineration, It is possible to cause serious environmental pollution due to the emission of harmful substances. In addition, when the landfill treatment is carried out, the FRP is hardly decomposed in the natural state, so that secondary contamination of the landfill by the landfill is interfered with, and securing the landfill is difficult.

In addition to not having such a proper waste disposal method, it has not reflected the cost related to disposal of waste at the time of development. Therefore, it has not been able to grasp the statistical status related to FRP waste generation and disposal even though it generates a huge amount of waste Waste FRP left untreated is causing serious environmental pollution. Therefore, it is urgently required to develop a technology for recycling the FRP waste material to prevent pollution of the environment and to make it a resource with high added value.

BACKGROUND ART [0002] The background art relating to the present invention is disclosed in Korean Patent Laid-Open Publication No. 2015-0074482 (published on May 21, 2015, entitled "Recycled Thermoplastic Material Excellent in Impact Strength").

An object of the present invention is to provide a method of manufacturing a molded article using waste fiber-reinforced plastic excellent in rigidity, flexural resistance, heat resistance, and impact resistance.

Another object of the present invention is to provide a molded article having excellent dimensional stability, a homogeneous mechanical strength, and a waste fiber reinforced plastic.

It is still another object of the present invention to provide a method of manufacturing a molded article using waste fiber reinforced plastic excellent in economic efficiency and environmental pollution prevention effect.

It is still another object of the present invention to provide a molded article produced by the method for producing a molded article using the waste fiber-reinforced plastic.

One aspect of the present invention relates to a method of manufacturing a molded article using waste fiber reinforced plastic. In one embodiment, the method for manufacturing a molded body using the waste fiber reinforced plastic comprises the steps of: pulverizing the waste fiber reinforced plastic to produce a pulverized product; And a fiber filler impregnated in the matrix resin, wherein the pressurization is carried out at a temperature of 150 to 250 DEG C and a temperature of 100 to 250 DEG C, At a pressure of 2,000 kgf / cm < 2 >, and ultrasonic vibration is applied to the pulverized material at the time of pressing to melt.

In one embodiment, the pulverization may pulverize the waste fiber-reinforced plastic to a size of 1 mu m to 100 mu m.

In one embodiment, the fiber filler includes at least one of carbon fiber, glass fiber, basalt fiber, aramid fiber, and boron fiber. The matrix resin may be at least one selected from the group consisting of phenol, polyvinyl chloride (PVC), acrylonitrile Butadiene-styrene (ABS), polyester, polyimide, epoxy, polyethylene (PE), polypropylene (PP), polyisobutylene polyisobutylene, and polyethylene terephthalate (PET).

In one embodiment, the waste fiber reinforced plastic may comprise 30-60 wt% glass fibers and 40-70 wt% polyester resin.

In one embodiment, the pulverized material may be preheated to 50 to 200 < 0 > C before being pressurized.

In one embodiment, the ultrasonic vibration may be applied to the pulverized material at a frequency of 15 kHz to 500 MHz and an amplitude of 0.5 to 20 μm.

Another aspect of the present invention relates to a molded article produced by the method for producing a molded article using the waste fiber-reinforced plastic.

The molded body produced by the method for producing a molded body using the waste fiber reinforced plastic of the present invention is excellent in dimensional stability, homogeneous mechanical strength, excellent in rigidity, flexural resistance, heat resistance and impact resistance, The plastic can be recycled, and the economic efficiency and environmental pollution prevention effect can be excellent.

FIG. 1 shows a method of manufacturing a molded body using waste fiber reinforced plastic according to one embodiment of the present invention.
Fig. 2 shows an apparatus for producing a molded article according to one embodiment of the present invention.
Fig. 3 (a) shows the waste fiber reinforced plastic, Fig. 3 (b) shows the waste fiber plastic primarily broken, and Fig. 3 (c) FIG.
4 is a photograph showing a molded article manufactured according to one embodiment of the present invention.
5 is a photograph showing a molded body manufactured according to another embodiment of the present invention.
FIG. 6 is a photograph showing a molded article manufactured according to another embodiment of the present invention. FIG.
7 is a photograph showing a molded body manufactured according to another embodiment of the present invention.

In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to be exemplary, self-explanatory, allowing for equivalent explanations of the present invention.

Using waste fiber reinforced plastic Shaped body  Manufacturing method

One aspect of the present invention relates to a method of manufacturing a molded article using waste fiber reinforced plastic. FIG. 1 shows a method of manufacturing a molded body using waste fiber reinforced plastic according to one embodiment of the present invention. Referring to FIG. 1, a method of manufacturing a molded body using waste fiber-reinforced plastic comprises the steps of (S10) preparing a pulverized product; And (S20) molding. In one embodiment, the method for manufacturing a molded article using the waste fiber reinforced plastic comprises the steps of: (S10) milling a waste fiber reinforced plastic to produce a pulverized product; And (S20) pressing the pulverized material to produce a molded body.

Wherein the waste fiber reinforced plastic comprises a matrix resin and a fiber filler impregnated in the matrix resin, and the pressing is performed at a temperature of 150 to 250 ° C and a pressure of 100 to 2,000 kgf / cm 2, By ultrasonic vibration.

Hereinafter, a method of manufacturing a molded body using the waste fiber reinforced plastic according to the present invention will be described in detail.

Fig. 2 shows an apparatus for producing a molded article according to one embodiment of the present invention. Referring to FIG. 2, the shaped body manufacturing apparatus 1000 includes a mixing part 130 in which the pulverized product 10 produced by pulverizing the waste fiber reinforced plastic is transferred through the first transfer line 201 to be uniformly mixed therewith; And a dosing device 202 for transferring the pulverized product 10 of the mixing part 130 and uniformly filling the lower mold 301; And a press molding machine 401 which press-molds the lower mold 301 to produce a molded product. In one embodiment, the pulverized material 10 is introduced into the mixing section 130 through the first transfer line 201 and mixed homogeneously. The pulverized material 10 is transferred to the constant-quantity charging apparatus 202, And is conveyed to the press molding machine 401 through the second conveyance line 203. Then, the upper mold 302 and the lower mold 301 are closed and pressed to manufacture a molded article. Thereafter, the lower mold 301 is separated from the upper mold 302 and transferred through the third transfer line 204 to take out the molded body. In one embodiment, ultrasonic vibration generators 410 and 411 are provided at the lower end of the pressure molding machine 401 to melt the crushed material 10 filled in the lower mold 301.

(S10) Crushed water  Manufacturing stage

The above step is a step of pulverizing waste fiber reinforced plastic to produce a pulverized product. The waste fiber reinforced plastic includes a matrix resin and a fiber filler impregnated in the matrix resin.

In one embodiment, the fiber filler may include at least one of carbon fiber, glass fiber, basalt fiber, aramid fiber, and boron fiber. For example, glass fibers.

In one embodiment, the matrix resin is selected from the group consisting of phenol, polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), polyester, polyimide ), Epoxy, polyethylene (PE), polypropylene (PP), polyisobutylene, and polyethyleneterephthalate (PET). For example, the matrix resin may include a polyester.

In one embodiment of the present invention, the waste fiber reinforced plastic may include 0.5 to 60% by weight of a fiber filler and 40 to 99.5% by weight of a matrix resin. The molded article produced using the waste fiber reinforced plastic including the fiber filler and the matrix resin in the above range can have excellent heat resistance, impact resistance and mechanical strength.

In one embodiment, the waste fiber reinforced plastic may comprise 30-60 wt% glass fibers and 40-70 wt% polyester resin. For example, the waste fiber reinforced plastic may include 30 to 35% by weight of glass fiber and 65 to 70% by weight of a polyester resin. By using the waste fiber reinforced plastic containing the above-mentioned amounts of glass fiber and polyester resin, moldability and dispersibility are excellent in the production of a molded article, so that a homogeneous molded article can be produced and the molded article can have excellent mechanical strength.

In one embodiment, the pulverization may be performed by pulverizing the waste fiber-reinforced plastic to a size of 1 탆 to 100 탆. The pulverization may be carried out using a conventional pulverizer. In the present specification, the " size " is defined as the maximum length of the waste fiber reinforced plastic. When the pulverized product is produced in the above-mentioned size, a molded product having excellent dispersibility and moldability of the fibrous filler and the matrix resin component to be described later and having uniform density and mechanical properties upon application of ultrasonic waves and pressurization can be produced. In one embodiment, the pulverized material may be mixed with an excess amount of water to remove impurities other than the fibrous filler and the matrix resin, followed by drying and preparing. For example, the pulverized product can be pulverized to a size of 10 to 40 탆.

(S20) Shaped body  Manufacturing stage

The above step is a step of pressing the pulverized material to produce a formed body. Referring to FIG. 2, in one embodiment, the pulverized material 10 is homogeneously mixed in the mixing section 130, then is transferred to the quantitative filling apparatus 202, and then charged into the lower mold 301, The mold 301 is conveyed to the press molding machine 401 through the second conveyance line 203.

Then, the upper mold 302 and the lower mold 301 are closed and pressed to manufacture a molded article. In one embodiment, ultrasonic vibration generators 410 and 411 are provided at the lower end of the press molding machine 401 to melt the crushed material 10 filled in the lower mold 301.

Referring to FIG. 2, the pulverized product 10 may be mixed with the molten resin 20 as needed before being transferred to the first transfer line 201. For example, the molten resin 20 may be selected from the group consisting of phenol, polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), polyester, And may include at least one of polyimide, epoxy, polyethylene (PE), polypropylene (PP), polyisobutylene, and polyethyleneterephthalate (PET) Lt; RTI ID = 0.0 > 200 C. < / RTI > Referring to FIG. 2, the molten resin 20 is stored in the molten resin storage unit 110, and may be mixed with the pulverized material 10 and air into the mixing tank 120 to be mixed.

In one embodiment, a conventional ultrasonic vibration generator may be used as the ultrasonic vibration generator.

In one embodiment, the pressing may be performed at a temperature of 150 to 250 ° C and a pressure of 100 to 2,000 kgf / cm 2. In one embodiment, the pulverized material may be pressed under the above conditions while applying ultrasonic vibration to the pulverized material. When the pulverized product is pressurized at a temperature of less than 150 ° C, sufficient melting is not performed and the strength of the molded product is lowered. When the product is pressurized at a temperature exceeding 250 ° C, the fibrous filler contained in the pulverized product is carbonized, The mechanical strength of the substrate can be lowered. Further, the mechanical strength of the molded article is lowered when the pressure is lower than 100 kgf / cm < 2 > and the moldability and mechanical strength of the molded article are lowered and the production cost is also increased when the pressure is higher than 2,000 kgf / .

In one embodiment, the ultrasonic wave serves to heat and melt the matrix resin component of the pulverized product to secure homogeneous mechanical strength of the molded product.

Referring to FIG. 2, in one embodiment of the present invention, ultrasonic vibration may be applied to the upper mold and the lower mold using the ultrasonic vibration generators 410 and 411 provided at the lower end of the press molding machine 401.

In another embodiment of the present invention, ultrasonic vibration may be applied while filling the lower mold 301 with the pulverized material and transferring the pulverized material through the third transfer line 203.

In one embodiment, the ultrasonic vibration may apply a frequency of 15 kHz to 500 MHz to the pulverized material. In one embodiment, the ultrasonic vibration can be applied at a frequency of 15 KHz to 300 MHz and an amplitude of 0.5 to 20 μm. As another example, it is possible to apply the voltage with a frequency of 10 MHz to 300 MHz and an amplitude of 0.5 to 20 μm. When the ultrasonic wave is applied under the frequency and amplitude conditions, the ultrasonic energy is easily transferred to the pulverized material, and the matrix resin component contained in the pulverized material is heated, so that the dispersibility and the mixing property can be excellent.

In one embodiment, the pulverized material may be preheated to 50 to 200 < 0 > C before being pressurized. When preheating to the above-mentioned temperature range, moisture contained in the pulverized product can be easily removed, and the moldability in the production of the molded product and the homogeneity of the formed product can be excellent. For example, 50 to 150 < 0 > C.

In another embodiment of the present invention, ultrasonic wave is irradiated to the pulverized material to dielectric-heat the molten matrix component.

Another aspect of the present invention relates to a molded article produced by the method for producing a molded article using the waste fiber-reinforced plastic. In one embodiment, the compact may have a compressive strength of 25 to 60 MPa as measured according to the KS L 8510 standard.

Hereinafter, the structure and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Example  One

A molded body was manufactured using the molded body manufacturing apparatus shown in Fig. Fig. 3 (a) is a view showing a waste fiber-reinforced plastic, Fig. 3 (b) is a view obtained by firstly crushing the waste fiber plastic, and Fig. 3 (c) is a photograph showing a pulverized product produced according to one embodiment of the present invention to be. 3, the waste fiber reinforced plastic containing 35 wt% of carbon fibers and 65 wt% of a matrix resin (polyester resin) was pulverized into 80 mu m in size to prepare a pulverized product 10 as shown in Fig. 3, The pulverized product was washed with water and hot air dried.

Then, the pulverized product 10 was transferred to the mixing portion 110 through the first transfer line 201 to uniformly mix the fiber and matrix resin components. The mixed pulverized product 10 was transferred through a quantitative filling device (auger filler) 202 to fill the lower mold 301. Thereafter, the pulverized product is preheated to 120 ° C. through the preheater 210 and transferred to the press molding machine 401 through the second transfer line 203 to mold the upper mold 302 and pressurize the press molding machine 401 Pressure ultrasonic vibration at a frequency of 1 MHz and an amplitude condition of 10 m was applied at a temperature of 200 DEG C and a pressure of 500 kgf / cm < ² > to produce a molded body, And transferred to the third transfer line 204 to produce a molded body as shown in Figs.

Example  2

The crushed material prepared in the same manner as in Example 1 was charged into a concavo-convex mold and subjected to ultrasonic vibration at a frequency of 1 MHz and an amplitude condition of 20 m from the ultrasonic vibration generators 410 and 411 provided in the pressure molding machine 401 while in the ultrasonic vibration, the formed body of the temperature, and 500kgf / cm to ² pressure pressurized in the manufacture of molded articles, and the second having the form also such as 7 to transfer to a third conveying line 204, the cross-sectional area 2500mm ² of 230 ℃ .

Comparative Example  One

A molded article was prepared in the same manner as in the above example, except that ultrasonic vibration was not applied.

Comparative Example  2

The molded body was produced in the same manner as in the above example except that the molded body was produced by pressing at a temperature of 125 캜 and a pressure of 500 kgf / cm ² .

Comparative Example  3

A shaped body was produced in the same manner as in the above example, except that a molded body was produced by pressing at a temperature of 265 캜 and a pressure of 500 kgf / cm ² .

Comparative Example  4

A molded body was produced in the same manner as in the above example except that a molded body was produced by pressing at a temperature of 200 DEG C and a pressure of 2,200 kgf / cm < ^{2 &} gt ;.

The compacts prepared in Example 1 and Comparative Examples 1 to 4 were measured for compressive strength based on the KS L 8510 standard and are shown in Table 1 below. The compression strengths in the horizontal direction and in the vertical direction of the molded article of Example 2 were measured according to the KS L 8510 standard and are shown in Table 2 below.

division Example 1 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Compressive strength (MPa) 43.5 18 20.5 17.5 30.5

Referring to the results of Tables 1 and 2, it can be seen that the compressive strength of Examples 1 and 2 prepared according to the present invention is higher than that of ordinary concrete (about 25 MPa). On the other hand, in the case of Comparative Examples 1 to 4, which were out of the pressurizing condition of the present invention, it was found that the compression strength of the molded article was lower than that of the above examples.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

10: Crushed product 20: Melt resin
110: molten resin storage part 120: mixing tank
130: mixing section 201: first transfer line
202: Quantitative charging device 203: Second transfer line
204: Third transfer line 210: Preheater
301: lower mold 302: upper mold
401: molding machine 410: ultrasonic vibration generator
411: Ultrasonic vibration generating unit 1000: Molded body manufacturing apparatus

Claims (7)

Pulverizing the waste fiber reinforced plastic to a size of 1 mu m to 100 mu m to produce a pulverized product; And
And pressing the pulverized material to produce a shaped body,
Wherein the waste fiber reinforced plastic comprises 40 to 99.5% by weight of a matrix resin and 0.5 to 60% by weight of a fiber filler impregnated in the matrix resin,
The pressurization is performed at a temperature of 150 to 250 DEG C and a pressure of 100 to 2,000 kgf /
Wherein the pulverized material is melted by applying ultrasonic vibration at a frequency of 15 kHz to 500 MHz and an amplitude of 0.5 to 20 탆 to the pulverized material at the time of pressing.
delete The fiber filler according to claim 1, wherein the fiber filler comprises at least one of carbon fiber, glass fiber, basalt fiber, aramid fiber and boron fiber,
The matrix resin may be selected from the group consisting of phenol, polyvinyl chloride (PVC), acrylonitrile-butadiene-styrene (ABS), polyester, polyimide, epoxy Characterized in that it comprises at least one selected from the group consisting of epoxy, polyethylene, PE, polypropylene (PP), polyisobutylene, and polyethylene terephthalate (PET) Gt;
The method according to claim 3, wherein the waste fiber reinforced plastic comprises 30 to 60% by weight of glass fiber and 40 to 70% by weight of polyester resin.
The method according to claim 1, wherein the pulverized material is preheated to 50 to 200 ° C before being pressurized.
delete A molded article produced by the method for producing a molded article using the waste fiber reinforced plastic according to any one of claims 1 to 5.

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