KR102163898B1 - Fiber reinforced composite material and method of manufacturing the same - Google Patents

Abstract

A first mixture comprising a thermoplastic resin and a first compatibilizer; And it provides a fiber-reinforced composite material comprising an extrudate of a mixed composition comprising a second mixture containing inorganic fibers and a second compatibilizer.

Description

Fiber-reinforced composite and its manufacturing method {FIBER REINFORCED COMPOSITE MATERIAL AND METHOD OF MANUFACTURING THE SAME}

It relates to a fiber-reinforced composite and a method of manufacturing the same.

A composite material used for various purposes is made by combining two or more materials, and can generally be manufactured by mixing a polymer resin with glass fiber or carbon fiber as a reinforcing material. In addition, there are thermoplastic resin compositions containing fibrous fillers and silicone rubber as essential components as composite materials, and molded articles manufactured using the same. Such composites can be used in industrial fields requiring high strength and rigidity. Accordingly, there is a need for research to have excellent strength and stiffness along with excellent flexibility, and at the same time secure economical efficiency.

One embodiment of the present invention provides a fiber-reinforced composite material that can simultaneously and economically secure excellent flexural modulus and tensile strength.

Another embodiment of the present invention provides a method of manufacturing the fiber-reinforced composite.

In one embodiment of the present invention, a first mixture comprising a thermoplastic resin and a first compatibilizer; And it provides a fiber-reinforced composite comprising an extrudate of a mixed composition comprising a second mixture containing inorganic fibers and a second compatibilizer.

In another embodiment of the present invention, preparing a first mixture comprising a thermoplastic resin and a first compatibilizer; Preparing a second mixture containing inorganic fibers and a second compatibilizer; First injecting the first mixture into an extruder through a first inlet and gradually applying heat to melt it while moving in the direction of the second inlet; Preparing a mixed composition in which the first mixture and the second mixture are mixed by injecting the second mixture into the at least partially melted first mixture through the second inlet; And preparing a fiber-reinforced composite material from the mixed composition.

The fiber-reinforced composite material can simultaneously and economically secure excellent flexural modulus and tensile strength, and can be widely used for various purposes.

1 schematically shows an extruder used in a method for manufacturing a fiber-reinforced composite according to an embodiment of the present invention.

Advantages and features of the present invention, and a method of achieving them will become apparent with reference to the embodiments to be described later. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various different forms, However, these embodiments are provided to complete the disclosure of the present invention, and to fully inform the scope of the invention to those of ordinary skill in the art to which the present invention pertains, and the present invention is defined by the scope of the claims. It just becomes.

In one embodiment of the present invention, a first mixture comprising a thermoplastic resin and a first compatibilizer; And it provides a fiber-reinforced composite material comprising an extrudate of a mixed composition comprising a second mixture containing inorganic fibers and a second compatibilizer.

The fiber-reinforced composite may have excellent impregnation property due to high interfacial adhesion between the thermoplastic resin and the inorganic fiber. Accordingly, the fiber-reinforced composite material can simultaneously secure an excellent flexural modulus and tensile strength more economically.

The first mixture includes a thermoplastic resin, and the thermoplastic resin includes polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide; PPO), polyvinyl chloride (PVC), polyethylene terephthalate (PET), nylon (Nylon) 6.6, polymethyl methacrylate (PMMA), and one selected from the group consisting of a combination thereof It may include.

For example, the first mixture may include polyethylene terephthalate (PET) as a thermoplastic resin. When the thermoplastic resin includes polyethylene terephthalate, it has price competitiveness and can impart excellent thermal and mechanical properties.

On the other hand, the polyethylene terephthalate has a relatively slow crystallization rate compared to other resins, for example, compared to polypropylene resins, and is sensitive to water, so it is easy to hydrolyze. I can. However, the fiber-reinforced composite includes a second mixture containing inorganic fibers and a second compatibilizer in the first mixture containing the polyethylene terephthalate and the first compatibilizer, and has excellent mechanical properties such as excellent flexural modulus and tensile strength. Can be secured at the same time.

The first mixture includes a first compatibilizer together with the thermoplastic resin, and the first compatibilizer may include phthalic anhydride or a derivative thereof. The first compatibilizer has high affinity with the thermoplastic resin, the inorganic fiber, and the second compatibilizer, and may improve the interfacial adhesion between the thermoplastic resin and the inorganic fiber. Specifically, the first compatibilizer is selected from the group consisting of trimellitic anhydride acid chloride (TAAC) tetrachlorophthalic anhydride, chloroacetic anhydride, and combinations thereof. It can be one.

The first mixture may include about 1.5 parts by weight to about 12.5 parts by weight of the first compatibilizer based on 100 parts by weight of the thermoplastic resin. Specifically, when the content of the first compatibilizer is less than the above range, it may not sufficiently react with the thermoplastic resin and inorganic fibers, and thus mechanical properties may not be sufficiently improved with low interfacial bonding strength. And, when the content of the first compatibilizer exceeds the above range, a by-product may be generated due to a side reaction between the first compatibilizer and the second compatibilizer, and accordingly, mechanical properties may be deteriorated. 1 The effect of increasing mechanical properties relative to the content of the compatibilizer may be insignificant.

The second mixture may include inorganic fibers, and may increase the strength and rigidity of the fiber-reinforced composite material, provide weight reduction and corrosion resistance, and may impart fatigue resistance and impact resistance. In the present specification, fatigue resistance is a record of the number of repetitions of the applied load required to cause fracture of the sample while applying a fixed load and a variable load to the specimen, and the greater the number of times, the better the fatigue resistance.

Specifically, the inorganic fiber may include one selected from the group consisting of glass fiber, carbon fiber, aramid, and combinations thereof.

The inorganic fibers may have an average diameter of about 15 μm to about 20 μm in cross section, and may be, for example, about 16 μm to about 19 μm. When the cross-section of the inorganic fiber has an average diameter of less than about 15 μm, the strength of the fiber-reinforced composite material may be significantly lowered. When the inorganic fiber has an average diameter of more than about 20 μm, the interfacial adhesion with the thermoplastic resin is increased. It can be degraded.

The fiber-reinforced composite material may include about 30 parts by weight to about 145 parts by weight of the inorganic fiber based on 100 parts by weight of the thermoplastic resin. When the inorganic fiber is included in less than the above range, it may be difficult to secure the required strength and rigidity of the composite material. In addition, when the content of the inorganic fibers exceeds the above range, the interaction between the inorganic fibers increases too much, so that the length of the inorganic fibers may be relatively reduced, and the orientation of the fibers may decrease. Accordingly, the mechanical properties of the fiber-reinforced composite material including the same may be rather deteriorated.

The inorganic fibers may be modified by a surface treatment agent. The second mixture contains inorganic fibers modified by a surface treatment agent together with a second compatibilizer to facilitate reaction and processability between the inorganic fibers and the second compatibilizer, thereby improving interfacial adhesion between the thermoplastic resin and the inorganic fibers. And increase the mechanical properties of the fiber-reinforced composite. For example, the glass fiber modified by the surface treatment agent can easily improve the interfacial adhesion with the thermoplastic resin through chemical bonding together with the second compatibilizer.

Specifically, the surface treatment agent may be a silane-based compound having a hydroxy group. The inorganic fiber may induce a chemical reaction between the thermoplastic resin and the inorganic fiber, the inorganic fiber and the second compatibilizer by surface modification by a silane-based compound having a hydroxy group. For example, the hydroxy group contained in the inorganic fiber glass fiber is in contact with the hydroxy group of the silane compound to facilitate bonding, and the adhesive strength may be more easily improved. In addition, the interfacial adhesion between the thermoplastic resin and the inorganic fiber may be further improved. Accordingly, desired physical properties can be obtained.

The second mixture may include a second compatibilizer together with the inorganic fiber, and the second compatibilizer may include an aromatic polyisocyanate compound. In the present specification,'aromatic polyisocyanate compound' should be understood as a generic term for a compound having an aromatic chemical structure while having at least two isocyanate groups.

The second mixture includes an aromatic polyisocyanate compound as a second compatibilizer, and the second compatibilizer can easily react with the thermoplastic resin, for example, polyethylene terephthalate, the inorganic fiber, and the first compatibilizer. Accordingly, economically excellent flexural modulus and tensile strength can be secured at the same time.

Specifically, the second compatibilizer is methylene diphenyl diisocyanate, p-phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,4'-diphenyl diisocyanate, 2,4'-diphenyl Methane diisocyanate, 1,5-naphthalene diisocyanate, 3,3'-methyleneditolylene-4,4'-diisocyanate, triphenylmethane triisocyanate, 4,4'-diphenylether diisocyanate, tetrachlorophenylene Diisocyanate, 3,3'-dichloro-4,4'-diphenylmethane diisocyanate, triisocyanate phenylthiophosphate, and combinations thereof.

The second mixture may include about 1.7 parts by weight to about 13.6 parts by weight of the second compatibilizer, based on 100 parts by weight of the inorganic fiber. If the content of the second compatibilizer is less than the above range, there is a problem that the effect of increasing the interfacial adhesion due to the addition of the second compatibilizer is insufficient, and if it exceeds the above range, the addition due to the reaction between the first compatibilizer and the second compatibilizer As a product is generated, the effect of increasing mechanical properties may not be sufficient.

The fiber-reinforced composite material includes an extrudate of a mixed composition comprising the first mixture and the second mixture, and the mixed composition may be formed by sequentially mixing the first mixture and the second mixture. A mixed composition may be formed by sequentially mixing the first mixture and the second mixture by a method described below.

The fiber-reinforced composite material includes an extrudate of a mixed composition formed by sequentially mixing the first mixture and the second mixture, and economically simultaneously secures excellent flexural modulus and tensile strength.

The second compatibilizer included in the second mixture has a higher reactivity than the first compatibilizer included in the first mixture. Therefore, in the case of manufacturing a fiber-reinforced composite material by simultaneously mixing and extruding the first mixture and the second mixture each containing the first compatibilizer and the second compatibilizer having different reactivity, desired properties cannot be obtained. For example, since the second compatibilizer has high reactivity, it may react with the thermoplastic resin and the inorganic fiber before the first compatibilizer. Accordingly, the extruded product of the mixed composition including the first mixture and the second mixture may have a different structure, and desired physical properties may not be sufficiently obtained therefrom.

In the fiber-reinforced composite, the second mixture including the second compatibilizer having high reactivity may be mixed later than the first mixture. By sequentially mixing the first mixture and the second mixture as described above, the structure of the extruded product of the mixed composition is appropriately controlled, so that excellent flexural modulus and tensile strength can be simultaneously secured.

The mixed composition may further include one additive selected from the group consisting of antioxidants, heat stabilizers, dispersants, pigments, and combinations thereof. For example, the additive may be included in about 1% to about 10% by weight in the mixed composition 　, for example, 　 contains about 1% to about 7% by weight of a compatibilizer, and about 1% by weight of a heat stabilizer It may contain to 3% by weight.

It may include about 20 parts by weight to about 300 parts by weight of the second compatibilizer relative to 100 parts by weight of the first compatibilizer. When the content of the second compatibilizer is less than the above range, the number of functional groups may not be sufficient, so that the effect of increasing the physical properties according to the addition of the second compatibilizer may not be sufficient. When it exceeds the above range, the reaction between the second compatibilizers It occurs predominantly, and the reactivity between the first compatibilizer and the second compatibilizer may decrease.

Another embodiment of the present invention provides a method of manufacturing a fiber-reinforced composite. 1 schematically shows an extruder used in the manufacturing method of a fiber-reinforced composite according to an embodiment of the present invention, and the manufacturing method of the fiber-reinforced composite is to prepare a first mixture containing a thermoplastic resin and a first compatibilizer. Step to do; Preparing a second mixture containing inorganic fibers and a second compatibilizer; First injecting the first mixture into the extruder through the first inlet 14 and gradually applying heat to melt it while moving in the direction of the second inlet 15; Preparing a mixed composition in which the first mixture and the second mixture are mixed by injecting the second mixture into the at least partially melted first mixture through the second inlet (15); And preparing a fiber-reinforced composite from the mixed composition.

Through the fiber-reinforced composite manufacturing method, it is possible to manufacture a fiber-reinforced composite material that can simultaneously secure economically excellent flexural modulus and tensile strength.

Specifically, the fiber-reinforced composite manufacturing method includes the steps of preparing a first mixture comprising a thermoplastic resin and a first compatibilizer; And preparing a second mixture comprising inorganic fibers and a second compatibilizer. It may include. Matters regarding the thermoplastic resin, the first compatibilizer, the inorganic fiber, and the second compatibilizer are as described above.

In addition, the fiber-reinforced composite manufacturing method includes the steps of firstly injecting the first mixture into the extruder through the first inlet 14 and gradually applying heat to melt it while moving in the direction of the first inlet 15; And preparing a mixed composition in which the first mixture and the second mixture are mixed by injecting the second mixture into the at least partially melted first mixture through the first inlet 15.

The second compatibilizer included in the second mixture has a higher reactivity than the first compatibilizer included in the first mixture. Therefore, in the case of manufacturing a fiber-reinforced composite material by simultaneously mixing and extruding the first mixture and the second mixture each containing the first compatibilizer and the second compatibilizer having different reactivity, desired properties cannot be obtained. For example, since the second compatibilizer has high reactivity, it may react with the thermoplastic resin and the inorganic fiber before the first compatibilizer. Accordingly, the extruded product of the mixed composition including the first mixture and the second mixture may have a different structure, and desired physical properties may not be obtained therefrom.

Accordingly, the fiber-reinforced composite material is firstly introduced into the extruder through the first inlet 14 and gradually heated to melt while moving in the direction of the first inlet 15, thereby at least partially melting The second mixture including the second compatibilizer having high reactivity may be mixed later than the first mixture by injecting the second mixture into the first mixture prepared through the first inlet 15. By sequentially mixing the first mixture and the second mixture as described above, the structure of the extruded product of the mixed composition is appropriately controlled, so that excellent flexural modulus and tensile strength can be simultaneously secured.

The fiber-reinforced composite manufacturing method includes the step of preparing a fiber-reinforced composite from the mixed composition. Specifically, by continuously extruding the mixed composition using an extrusion die, an extrudate having a predetermined size and shape may be manufactured. In addition, the extruded product may be press-molded to manufacture the fiber-reinforced composite.

The fiber-reinforced composite material manufactured through the fiber-reinforced composite manufacturing method can economically secure excellent flexural modulus and tensile strength at the same time.

Hereinafter, specific embodiments of the present invention are presented. However, the examples described below are merely for illustrating or explaining the present invention in detail, and the present invention is not limited thereto.

< Example And Comparative example >

Example One

A first mixture comprising polyethylene terephthalate and 8 parts by weight of trimellitic anhydride acid chloride (TAAC) relative to 100 parts by weight of the polyethylene terephthalate and an antioxidant was prepared. In addition, a second mixture containing 9 parts by weight of methylene diphenyl diisocyanate (MDI) relative to 100 parts by weight of glass fibers and the glass fibers was prepared.

The first mixture is introduced into the first inlet 14 and gradually heated to melt while moving in the direction of the second inlet 15, and the at least partially melted first mixture is melted through the second inlet 15. The second mixture was added to prepare a mixed composition.

At this time, the second mixture was added so that the methylenediphenyl diisocyanate was included in an amount of 60 parts by weight relative to 100 parts by weight of trimellitic anhydride chloride. Subsequently, the mixed composition was continuously extruded using an extrusion die to press molding to prepare a fiber-reinforced composite.

Comparative example One

A fiber-reinforced composite was prepared in the same manner as in Example 1, except for preparing a second mixture that does not contain methylene diphenyl diisocyanate (MDI).

Comparative example 2

A fiber-reinforced composite was prepared in the same manner as in Example 1, except that a first mixture not containing trimellitic anhydride acid chloride (TAAC) was prepared.

Comparative example 3

A fiber-reinforced composite was manufactured in the same manner as in Example 1, except that the first mixture and the second mixture were added to the first inlet 14 to prepare a mixed composition.

<Evaluation>

Experimental example 1: flexion Modulus of elasticity (kg/㎠)

The specimens of Examples and Comparative Examples were measured for flexural modulus using Instron's 5569A, universal testing machine (UTM) at a rate of 3 mm/min at room temperature of 23 °C according to ASTM D790, and the results are shown in Table 1 below.

Experimental example 2: Tensile strength (MPa)

For the specimens of Examples and Comparative Examples according to ASTM D638, the size of the specimen follows Type 1, and the tensile strength was measured using Instron's 5569A, Universal Testing Machine (UTM) at a tensile speed of 5mm/min, and the results are shown in Table 1 below. Shown in.

Flexural modulus (kg/㎠) Tensile strength (MPa) Example 1 11.2 162 Comparative Example 1 8.6 148 Comparative Example 2 8.9 150 Comparative Example 3 9.0 153

10: extruder
11: barrel
12: rotating shaft
13: screw
14: first inlet
15: second inlet

Claims (13)

A first mixture comprising polyethylene terephthalate (PET) and trimellitic anhydride acid chloride (TAAC); And
Including an extrudate of a mixed composition comprising a second mixture containing inorganic fibers and methylenediphenyl diisocyanate,
The inorganic fibers include one selected from the group consisting of glass fibers, carbon fibers, and combinations thereof.
Fiber reinforced composites.
The method of claim 1,
The second mixture does not contain a thermoplastic resin
Fiber reinforced composites.
delete The method of claim 1,
Containing 20 parts by weight to 300 parts by weight of the methylene diphenyl diisocyanate relative to 100 parts by weight of trimellitic anhydride chloride
Fiber reinforced composites.
delete The method of claim 1,
The inorganic fiber is modified by a surface treatment agent
Fiber reinforced composites.
The method of claim 6,
The surface treatment agent is a silane-based compound having a hydroxy group
Fiber reinforced composites.
delete The method of claim 1,
The inorganic fibers have an average diameter of 15 μm to 20 μm
Fiber reinforced composites.
The method of claim 1,
The first mixture comprises 1.5 parts by weight to 12.5 parts by weight of trimellitic anhydride, based on 100 parts by weight of the polyethylene terephthalate.
Fiber reinforced composites.
The method of claim 1,
The second mixture comprises 1.7 parts by weight to 13.6 parts by weight of the methylene diphenyl diisocyanate relative to 100 parts by weight of the inorganic fiber.
Fiber reinforced composites.
The method of claim 1,
The mixed composition is formed by sequentially mixing the first mixture and the second mixture
Fiber reinforced composites.
Preparing a first mixture comprising polyethylene terephthalate and trimellitic anhydride chloride;
Preparing a second mixture comprising inorganic fibers and methylenediphenyldiisocyanate;
First injecting the first mixture into an extruder through a first inlet and gradually applying heat to melt it while moving in the direction of the second inlet;
Preparing a mixed composition in which the first mixture and the second mixture are mixed by injecting the second mixture into the at least partially melted first mixture through the second inlet; And
Including; preparing a fiber-reinforced composite from the mixed composition,
The inorganic fibers include one selected from the group consisting of glass fibers, carbon fibers, and combinations thereof.
Method for producing fiber-reinforced composites.

Images