WO2018044007A1 - Fiber-reinforced composite material and automobile interior/exterior material employing same - Google Patents

Abstract

Provided is a fiber-reinforced composite material comprising: a middle layer; and surface layers laminated on both surfaces of the middle layer, respectively, wherein the middle layer comprises a first thermoplastic resin and a first inorganic fiber, the surface layers comprise a second thermoplastic resin and a second inorganic fiber, and the wt% content of the second inorganic fiber among each of the entire surface layers is larger than the wt% content of the first inorganic fiber among the entire middle layer.

Description

Fiber Reinforced Composites and Automobile Interior and Exterior Materials

It relates to a fiber reinforced composite material and interior and exterior materials for automobiles using the same.

Composites utilized for various purposes are made of a combination of two or more materials, generally can be prepared by mixing a glass fiber or carbon fiber and the like as a reinforcing material to a polymer resin. In addition, there is a thermoplastic resin composition containing a fibrous filler and silicone rubber as an essential component as a composite material and a molded article manufactured using the same. Such a composite material can be utilized in industrial fields requiring high strength and rigidity, and it is necessary to study to secure light weight at the same time having excellent strength and rigidity with excellent flexibility.

One embodiment of the present invention provides a fiber-reinforced composite with improved flexural performance while maintaining light weight.

In one embodiment of the present invention, the intermediate layer and a surface layer laminated on both sides of the intermediate layer, the intermediate layer comprises a first thermoplastic resin and a first inorganic fiber, the surface layer is a second thermoplastic resin and a second inorganic fiber To include, wherein the weight percent content of the total of each of the surface layer of the second inorganic fiber is greater than the weight percent content of the total of the intermediate layer of the first inorganic fiber provides a fiber reinforced composite.

In another embodiment of the present invention, there is provided a vehicle interior and exterior material comprising a molding formed from the fiber-reinforced composite.

The fiber-reinforced composite material can ensure excellent flexural performance such as significantly superior flexural strength and flexural modulus while maintaining light weight. As a result, it can be utilized for automotive interior and exterior materials that require excellent flexural strength and flexural modulus, and lightweight.

1 schematically shows a cross-sectional view of a fiber reinforced composite 100 according to one embodiment of the invention.

Advantages and features of the present invention, and methods for achieving the same will be apparent with reference to the following embodiments. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. The present embodiments are merely provided to make the disclosure of the present invention complete, and to fully convey the scope of the invention to those skilled in the art, and the present invention is defined by the scope of the claims. It will be. Like reference numerals refer to like elements throughout.

In one embodiment of the present invention, the intermediate layer and a surface layer laminated on both sides of the intermediate layer, the intermediate layer comprises a first thermoplastic resin and a first inorganic fiber, the surface layer is a second thermoplastic resin and a second inorganic fiber To include, wherein the weight percent content of the total of each of the surface layer of the second inorganic fiber is greater than the weight percent content of the total of the intermediate layer of the first inorganic fiber provides a fiber reinforced composite.

Typically, the composite may be prepared by mixing a fiber reinforcing material such as inorganic fibers in a thermoplastic resin. The higher the content of the fiber reinforcement, the higher the strength and stiffness of the composite, but at the same time the brittleness (brittleness), the specific gravity of the composite as a whole, the quality of the composite deteriorates.

The fiber-reinforced composite may exhibit a significantly superior flexural strength and flexural modulus while maintaining lightness, including a low content of inorganic fibers as a whole.

1 schematically shows a cross-sectional view of a fiber reinforced composite 100 according to an embodiment of the present invention. Referring to this, the fiber reinforced composite 100 is laminated on both surfaces of the intermediate layer 10 and the intermediate layer. It has a sandwich structure including the surface layer 20 is made. The fiber reinforced composite 100 may include the intermediate layer 10 or the surface layer 20 as a single layer, or may include multiple layers.

The fiber reinforced composite may have a thickness of about 5.5 to about 7.5 mm. The fiber-reinforced composite may have a thickness in the above range, exhibiting significantly superior flexural strength and flexural modulus.

The intermediate layer includes a first thermoplastic resin and a first inorganic fiber, and the surface layer laminated on both surfaces of the intermediate layer includes a second thermoplastic resin and a second inorganic fiber. The weight percent content of each of the second inorganic fibers included in each surface layer of the fiber reinforced composite is greater than the weight percent content of the first inorganic fibers included in the intermediate layer. That is, the fiber-reinforced composite material can increase the content of the second inorganic fiber of the surface layer located on the outer shell, thereby exhibiting excellent bending strength and bending elastic modulus.

In addition, the fiber-reinforced composite material is lower than the content of the second inorganic fiber of the first inorganic fiber of the intermediate layer located between the surface layer, the total of the first inorganic fiber and the second inorganic fiber of the fiber reinforced composite The content can be lowered. Accordingly, the fiber-reinforced composite material can exhibit flexural performance such as excellent flexural strength and flexural modulus while maintaining lightness.

In one embodiment, the content of the second inorganic fiber included in each of the surface layers may be greater than about 60 to about 90 wt%. The fiber-reinforced composite material includes the second inorganic fibers in the above range in each of the outer surface layers located in the outer shell so that the second inorganic fibers are properly impregnated in the second thermoplastic resin to prevent voids from occurring in the surface layer. can do. Accordingly, it is possible to exhibit flexural performance such as excellent flexural strength and flexural modulus.

In addition, the content of the first inorganic fiber included in the intermediate layer may be about 30 wt% to about 60 wt%. Since the first inorganic fiber is included in the intermediate layer in the content of the above range, the fiber-reinforced composite material including the same may exhibit excellent bending strength and flexural modulus while maintaining light weight.

In one embodiment, the content of the first inorganic fiber and the second inorganic fiber of the entire fiber reinforced composite may be about 50 to about 70 wt%. The content of the first inorganic fiber and the second inorganic fiber contained in the fiber-reinforced composite as a whole may be less than the content of the second inorganic fiber included in each surface layer. Accordingly, the fiber-reinforced composite can ensure excellent bending performance such as significantly superior flexural strength and flexural modulus while maintaining weight reduction. As a result, it can be utilized for automotive interior and exterior materials that require excellent flexural strength and flexural modulus, and lightweight.

The fiber reinforced composite may have a flexural strength of about 350 MPa to about 500 MPa by ASTM D790. Flexural strength is the maximum tensile stress at break in a bending test. The fiber reinforced composite includes the intermediate layer and a surface layer laminated on both sides of the intermediate layer, and includes the weight percent content of the second inorganic fiber contained in the entirety of each of the surface layers located on the outer surface of the fiber reinforced composite in the entire intermediate layer. By greater than the weight percent content of the first inorganic fiber, it can have excellent flexural strength in the above range.

In addition, the fiber reinforced composite may have a flexural modulus of about 15 GPa to about 30 GPa by ASTM D790. Flexural modulus represents the degree of force that resists bending when a force is applied from the outside. It can be seen that the fiber-reinforced composite material has excellent flexural modulus as well as flexural strength.

Therefore, the fiber-reinforced composite material can secure excellent flexural strength and flexural modulus without the phenomenon of cracking or chipping, and at the same time can maintain light weight.

Each of the first inorganic fibers included in the intermediate layer or the second inorganic fibers included in each of the surface layers may be the same or different kinds. For example, it may include one selected from the group consisting of carbon fiber, glass fiber, aramid and combinations thereof.

The average diameter of the cross section of each of the first inorganic fiber or the second inorganic fiber may be 15㎛ to 20㎛. Since the first inorganic fiber or the second inorganic fiber has a diameter in the above range, it can be contained in the fiber-reinforced composite material in a high content to implement excellent flexural strength and flexural rigidity, it is advantageous to ensure the lightweight properties, manufacturing It may be advantageous in terms of processability of the process.

In addition, each of the first inorganic fiber or the second inorganic fiber may be included in the form of a continuous fiber. In this case, the continuous fiber means that it is present in a continuous form without breaking inside depending on the final size of the fiber-reinforced composite material. For example, such as continuous fibers in a UD sheet (unidirection sheet), the continuous fibers can be made in a continuous process, and by supplying the continuous fibers continuously to such continuous processes, fiber reinforced composites comprising continuous fibers are produced. can do. Thus, the fiber reinforced composite can be made into a product of a particular shape, such as a sheet, in which the continuous fiber has a specific range of lengths depending on the shape of the product. However, this particular range of lengths should be viewed as having a 'continuity' in that it can be arbitrarily controlled in the manufacturing process in which the continuous fibers are continuously fed, and most of the continuous fibers, such as continuous fibers in a UD sheet or fabric, If it does not break inside the product, it has continuity.

Since the fiber-reinforced composite material includes continuous fibers rather than long or short fibers, there is no problem of dispersibility of the fibers and may include a high content of fibers. Accordingly, the fiber-reinforced composites have improved mechanical properties, such as excellent surface quality and even physical properties, high strength properties, and the like. Typically, short fibers means fibers of about 1 mm or less, and long fibers may mean fibers of about 50 mm or less. When such short fibers or long fibers are used, there is a problem of dispersibility in the composition, so that the fibers cannot be contained in a high content. In addition, there is a problem that the surface quality of the composite material is lowered, and physical properties such as mechanical strength are inferior.

As such, the fiber-reinforced composite material can be provided with excellent flexural strength and flexural modulus by including inorganic fibers in the form of continuous fibers.

The fiber reinforced composite may comprise about 40% to about 70% by weight of thermoplastic resin. The thermoplastic resin may be included in the content in the above range so that the fibers may be impregnated evenly during the manufacturing process, and the fiber-reinforced composite may secure a predetermined level or more of supporting performance.

The intermediate layer may include about 40 wt% to about 70 wt% of the first thermoplastic resin, and each of the surface layers may include about 10 wt% to about 40 wt% of the second thermoplastic resin. The thermoplastic resin may be included in the content in the above range so that the fibers may be impregnated evenly during the manufacturing process, and the fiber-reinforced composite may secure a predetermined level or more of supporting performance.

Each of the first thermoplastic resin included in the intermediate layer or the second thermoplastic resin included in each of the surface layers may be the same or different kinds. For example, aromatic vinyl resin, rubber modified aromatic vinyl resin, polyphenylene ether resin, polycarbonate resin, polyester resin, methacrylate resin, polyarylene sulfide resin, polyamide resin It may include one selected from the group consisting of polyvinyl chloride-based resin, polyolefin-based resin and combinations thereof.

For example, the thermoplastic resin may include a polyolefin resin, and specifically, may include a polypropylene resin. When the thermoplastic resin includes a polypropylene-based resin, it may be advantageous in terms of price competitiveness and may be advantageous in improving flexural strength and flexural modulus characteristics of the fiber reinforced composite. More specifically, the polypropylene-based resin may include polypropylene alone or a resin in which polypropylene and other types of monomers are copolymerized. For example, polypropylene homopolymerized resin, propylene-ethylene copolymerized resin, and propylene-butene copolymerized Resin, ethylene-propylene-butene copolymer resin, and combinations thereof.

The surface layer is a unidirectional continuous fiber reinforced plastic impregnated sheet formed by impregnating the second inorganic fiber into the second thermoplastic resin, and the intermediate layer is a unidirectional continuous fiber reinforced plastic formed by impregnating the first inorganic fiber into the first thermoplastic resin. Impregnated sheets.

The unidirectional continuous fiber-reinforced plastic impregnated sheet may be a sheet formed by including and oriented inorganic fibers in one direction in a thermoplastic resin that is a base material.

The unidirectional continuous fiber-reinforced plastic impregnated sheet is manufactured by a method of impregnating inorganic fibers side by side and then impregnated in a liquid resin, or in a method such as hot pressing after laminating inorganic fibers and thermoplastic resin sheets arranged side by side. The thermoplastic resin may be prepared by impregnating the inorganic fiber by applying heat thereto, and may be prepared without limitation by known methods, and commercially available.

In one embodiment, usually continuous fibers are commercially available as fiber filament bundles, which unfold such fiber filament bundles to a desired thickness (also referred to as 'broadening'), and in turn extend these unfolded fiber filament bundles in the width direction. When arranged in, the fiber filaments may be continuously arranged side by side in the width direction to have a sheet shape. After stacking the resin sheets up, down, or up and down of the continuous fibers arranged side by side in sheet form, heat is applied so that the molten resin is impregnated into the inorganic fibers and impregnated to form a unidirectional continuous fiber reinforced plastic impregnated sheet. It can manufacture.

The fiber reinforced composite may comprise continuous fibers such that the continuous fibers have a single orientation, such as a UD sheet.

1 schematically shows a top view of a fiber reinforced composite 100 according to one embodiment of the invention. Referring to FIG. 1, the fiber reinforced composite 100 includes a continuous fiber 30, wherein the continuous fiber may have a single orientation in the fiber reinforced composite. Since the continuous fibers have a single orientation in the fiber reinforced composite, it is advantageous to secure excellent flexural strength and flexural modulus, and is properly mixed with the thermoplastic resin in the fiber reinforced composite to improve the flexural performance of the fiber reinforced composite. It may be more advantageous to.

In one embodiment, the first inorganic fibers included in the intermediate layer and the second inorganic fibers included in the surface layer may have a single same orientation. Accordingly, the fiber reinforced composite material including the intermediate layer and the surface layer laminated on both surfaces of the intermediate layer may exhibit excellent bending characteristics such as more improved flexural strength and flexural modulus.

Specifically, that the continuous fibers have a single orientation means that when one particular fiber strand is selected from the continuous fibers in the thermoplastic resin, the angle of the particular continuous fibers with any other continuous fibers is about 10 ° or less, specifically about It should be understood to include cases of less than or equal to 5 °, and not only to be completely parallel to each other, but also to cases that are not parallel to an error range that is difficult to identify when visually observed.

In another embodiment of the present invention, there is provided a vehicle interior and exterior material comprising a molding formed from the fiber-reinforced composite. As described above, the fiber-reinforced composite material can secure excellent flexural performance such as significantly superior flexural strength and flexural modulus while maintaining lightness. As a result, it can be utilized for automotive interior and exterior materials that require excellent flexural strength and flexural modulus, and lightweight.

The fiber-reinforced composite may be manufactured into a molding by a compounding method through an extruder, a pultrusion method or a method through an extruder and an impregnation mold. The molding may include, for example, exterior materials such as back beams, seat backs, bonnets, roofs, and steering column covers, consoles, door panels, columns, supports, handles, buttons, handles. In addition to excellent flexural strength and flexural modulus, such as interior materials such as, and safety screens, it can be used for automotive interior and exterior materials requiring lightweight.

The following presents specific embodiments of the present invention. However, the embodiments described below are merely for illustrating or explaining the present invention in detail, and thus the present invention is not limited thereto.

< Example  And Comparative example >

Example  One

A thermoplastic resin composition composed of polypropylene homopolymerized resin was prepared. Subsequently, the thermoplastic resin was introduced into the composite material in the form of a continuous fiber from a roving form to the thermoplastic resin. At this time, the glass fibers were introduced to exhibit a single orientation in the composite. The thermoplastic resin composition was impregnated into the glass fiber and pressed by a calender process to prepare a unidirectional continuous fiber reinforced plastic impregnated sheet.

At this time, a 1 mm thick unidirectional continuous fiber-reinforced plastic impregnated sheet including 65 wt% of glass fiber and 35 wt% of polypropylene as a second inorganic fiber was prepared as a surface layer, and 55 wt% of glass fiber as the first inorganic fiber and A 4.4 mm thick unidirectional continuous fiber reinforced plastic impregnated sheet comprising 45 wt% polypropylene was prepared as an intermediate layer. A fiber reinforced composite of 6.4 mm was prepared by laminating each surface layer on both sides of the intermediate layer so that the first inorganic fiber and the second inorganic fiber had the same unidirectional orientation.

Example  2

A 1 mm thick unidirectional continuous fiber-reinforced plastic impregnated sheet comprising 70% by weight of glass fiber and 30% by weight of polypropylene as the second inorganic fiber was prepared as the surface layer, and 50% by weight of glass fiber and polypropylene as the first inorganic fiber. A 6.4 mm fiber-reinforced composite material was prepared in the same manner as in Example 1 except that a 4.4 mm thick unidirectional continuous fiber reinforced plastic impregnated sheet containing 50 wt% was prepared as an intermediate layer.

Example 3

A 1 mm thick unidirectional continuous fiber-reinforced plastic impregnated sheet comprising 75 wt% glass fiber and 25 wt% polypropylene as a second inorganic fiber was prepared as a surface layer, and 45 wt% glass fiber and polypropylene as a first inorganic fiber. A 6.4 mm fiber-reinforced composite material was prepared in the same manner as in Example 1, except that a 4.4 mm thick unidirectional continuous fiber reinforced plastic impregnated sheet containing 55 wt% was prepared as an intermediate layer.

Comparative Example 1

A thermoplastic resin composition composed of polypropylene homopolymerized resin was prepared. Subsequently, the thermoplastic resin was introduced into the composite material in the form of a continuous fiber from a roving form to the thermoplastic resin. At this time, the glass fibers were introduced to exhibit a single orientation in the composite. The thermoplastic resin composition was impregnated into the glass fiber and pressed by a calender process to prepare a unidirectional continuous fiber reinforced plastic impregnated sheet.

At this time, the unidirectional continuous fiber-reinforced plastic impregnated sheet contained 60% by weight of glass fiber and 40% by weight of polypropylene and had a thickness of 6.4 mm to prepare a fiber reinforced composite.

		Example 1	Example 2	Example 3	Comparative Example 1
Inorganic fiber content (% by weight) (glass fiber)	Second inorganic fiber (surface layer)	65	70	75
	First inorganic fiber (middle layer)	55	50	45
	Second inorganic fiber (surface layer)	65	70	75
	Inorganic Fiber in Fiber Reinforced Composites	60	60	60	60
Thickness of Fiber Reinforced Composite (mm)	6.4

<Evaluation>

About the fiber reinforced composites of the said Example and the comparative example, the physical property of the fiber reinforced composite material was evaluated according to the experiment example mentioned later.

Experimental Example  1: Measurement of Flexural Strength

Flexural strength was measured by ASTM D790 for the fiber reinforced composite, and the results are shown in Table 1 below.

Experimental Example  2: bend Modulus of elasticity  Measure

Flexural modulus was measured by ASTM D790 for the fiber reinforced composite, and the results are shown in Table 1 below.

	Example 1	Example 2	Example 3	Comparative Example 1
Flexural Strength (MPa)	360	370	400	307
Flexural Modulus (GPa)	27	28	30	24.1

As shown in Table 2, although the fiber-reinforced composites of the Examples and Comparative Examples contain almost the same amount of glass fibers, the fiber-reinforced composites of the Examples have significantly superior effects in flexural modulus as well as flexural strength. It can be seen that.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of the invention.

<Description of the code>

100: fiber reinforced composite

10: middle layer

20: surface layer

30: continuous fiber

Claims (13)

1. An intermediate layer and a surface layer laminated on both sides of the intermediate layer,

   The intermediate layer includes a first thermoplastic resin and a first inorganic fiber,

   The surface layer comprises a second thermoplastic resin and a second inorganic fiber,

   The wt% content of the entirety of each of the surface layers of the second inorganic fiber is greater than the wt% content of the entire intermediate layer of the first inorganic fiber.

   Fiber reinforced composites.
2. The method of claim 1,

   Each of the first inorganic fiber or the second inorganic fiber includes one selected from the group consisting of carbon fiber, glass fiber, aramid, and combinations thereof.

   Fiber reinforced composites.
3. The method of claim 1,

   Each of the first inorganic fiber or the second inorganic fiber is a continuous fiber

   Fiber reinforced composites.
4. The method of claim 1,

   The surface layer is a unidirectional continuous fiber reinforced plastic impregnated sheet formed by impregnating the second inorganic fiber with the second thermoplastic resin,

   The intermediate layer is a unidirectional continuous fiber reinforced plastic impregnated sheet formed by impregnating the first inorganic fiber with the first thermoplastic resin.

   Fiber reinforced composites.
5. The method of claim 1,

   The average diameter of the cross section of each of the first inorganic fiber or the second inorganic fiber is 15㎛ to 20㎛

   Fiber reinforced composites.
6. The method of claim 1,

   The content of the second inorganic fiber contained in each surface layer is 60 to 90 wt%

   Fiber reinforced composites.
7. The method of claim 1,

   The content of the first inorganic fiber included in the intermediate layer is 30 to 60wt%

   Fiber reinforced composites.
8. The method of claim 1,

   The content of the first inorganic fiber and the second inorganic fiber in the entire fiber reinforced composite material is 50 ~ 70 wt%

   Fiber reinforced composites.
9. The method of claim 1,

   Each of the first thermoplastic resin or the second thermoplastic resin is an aromatic vinyl resin, a rubber-modified aromatic vinyl resin, a polyphenylene ether resin, a polycarbonate resin, a polyester resin, a methacrylate resin, or a polyarylene. It includes one selected from the group consisting of sulfide resin, polyamide resin, polyvinyl chloride resin, polyolefin resin and combinations thereof

   Fiber reinforced composites.
10. The method of claim 1,

    The thickness of the fiber reinforced composite is 5.5 to 7.5 mm

    Fiber reinforced composites.
11. The method of claim 1,

    The fiber reinforced composite has a flexural modulus of 15 GPa to 30 GPa according to ASTM D790

    Fiber reinforced composites.
12. The method of claim 1,

    The fiber reinforced composite has a flexural strength of 350 MPa to 500 MPa according to ASTM D790

    Fiber reinforced composites.
13. An automotive interior and exterior material comprising a molding formed from the fiber reinforced composite according to any one of claims 1 to 12.

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