KR101782197B1 - Continuous fiber reinforced composite with well-impregnated and method for manufacturing of the same - Google Patents

Abstract

The present invention relates to a continuous fiber comprising 10% to 20% by weight of continuous fibers; 60% to 80% by weight of a thermoplastic resin; And 0.01 to 20% by weight of a compatibilizing agent. The continuous fiber reinforced composite material is excellent in impregnation properties and tensile properties, and a method for producing the same.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous fiber-reinforced composite material having excellent impregnation properties and a method for producing the same,

The present invention relates to a continuous fiber reinforced composite material excellent in impregnation property and a method for producing the same.

Composite materials are used for automotive back beams, bonnets, roofs, and the like. The composite material is formed by a combination of two or more materials, and one material, called a reinforcing phase, is in the form of fibers, plates, particles and is buried in another material called a matrix phase . The stiffener shall have high strength and high rigidity, and the length of the fiber shall be more than a certain length. Continuous fibers have excellent mechanical strength, stiffness and impact performance compared to long-fiber reinforced plastics with a length of 5 to 50 mm, such as Long Fiber-reinforced Thermoplastics (LFT) or Glass Matte Reinforced Thermoplastics (GMT).

Recently, in order to maximize the mechanical properties of a composite material, a composite material having a structure in which a continuous fiber and a thermoplastic resin are combined is manufactured. However, since the interfacial affinity between the continuous fibers and the thermoplastic resin is weakened, satisfactory impregnability can not be obtained, and therefore, there is a problem that the maximum physical property can not be reached.

The present invention relates to a continuous fiber comprising 10% to 20% by weight of continuous fibers; 60% to 80% by weight of a thermoplastic resin; And 0.01 to 20% by weight of a compatibilizing agent. The continuous fiber reinforced composite material is excellent in infiltration property and tensile property, and a method for producing the same.

However, the technical problem to be solved by the present invention is not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

In one embodiment of the invention, 10 to 20 wt.% Of continuous fibers; 60% to 80% by weight of a thermoplastic resin; And 0.01 to 20% by weight of a compatibilizing agent. The continuous fiber reinforced composite material is excellent in impregnation properties and tensile properties.

The fibers may be selected from the group consisting of glass fibers, bar-cut fibers, carbon fibers, aramid fibers, and combinations thereof.

The average diameter of the continuous fibers may be from 5 탆 to 20 탆.

The thermoplastic resin may include a first thermoplastic resin and a second thermoplastic resin.

The first thermoplastic resin or the second thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO) And may include one selected from the group consisting of polyvinyl chloride (PVC), polyethylene terephthalate (PET), nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof .

In another embodiment of the present invention, there is provided a method of producing a continuous fiber sheet, comprising the steps of: a) preparing a continuous fiber film impregnated with a first thermoplastic resin composition in continuous fibers; b) injecting and melting the second thermoplastic resin composition into a first extruder; And c) melt-kneading the continuous fiber film prepared in a) and the second thermoplastic resin composition melted in b) into a second extruder and melt-kneading the same, wherein the long fiber reinforced thermoplastic-direct compounding (LFT-D) The present invention also provides a method of producing a continuous fiber reinforced composite material excellent in impregnation property.

The continuous fiber film may be one obtained by melt-kneading the continuous fiber and the first thermoplastic composition.

The average diameter of the continuous fibers may be from 5 탆 to 20 탆.

The continuous fiber film may be formed by alternately stacking the continuous fibers and the first thermoplastic resin composition layers.

The total thickness of the continuous fiber layer may be between 20 μm and 65 μm.

The total thickness of the first thermoplastic resin composition layer may be 10 탆 to 200 탆.

The fibers may be selected from the group consisting of glass fibers, bar-cut fibers, carbon fibers, aramid fibers, and combinations thereof.

The first thermoplastic resin or the second thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO) And may include one selected from the group consisting of polyvinyl chloride (PVC), polyethylene terephthalate (PET), nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof .

The continuous fiber-reinforced composite material according to the present invention can be obtained by using a continuous fiber film in which the first thermoplastic resin composition is previously impregnated with the continuous fiber. Even if the compatibilizer is not further used, the second thermoplastic resin composition, And has excellent bending properties such as flexural strength and flexural modulus, and excellent tensile properties such as tensile strength and tensile elastic modulus.

1 shows a method of manufacturing a continuous fiber-reinforced composite according to an embodiment of the present invention.

The inventors of the present invention have been studying continuous fiber-reinforced composites having excellent impregnation properties, and have found that continuous fiber-reinforced composites are produced by using a continuous fiber film impregnated with a thermoplastic resin composition in continuous fibers, Thereby completing the present invention.

The present invention relates to a continuous fiber comprising 10% to 20% by weight of continuous fibers; 60% to 80% by weight of a thermoplastic resin; And 0.01 to 20% by weight of a compatibilizing agent, wherein the continuous fiber reinforced composite material is excellent in bending property and tensile property.

Continuous fiber

The continuous fibers are formed by stacking individual continuous fibers arranged in parallel to one another in the longitudinal direction of the fibers. The continuous fibers are long fiber-reinforced thermoplastics (LFT) or glass mat reinforced thermoplastics (GMT) The continuous fibers are preferably excellent in mechanical strength, stiffness and impact performance as compared with reinforced plastics. The continuous fibers are preferably 10 wt% to 20 wt%, but are not limited thereto. When the content of the continuous fibers is less than the above range, the physical properties such as strength and stiffness are not significantly developed, and the physical properties of the composite material are deteriorated. When the content of the continuous fibers exceeds the above range, application of the LFT-D process This is a difficult problem.

The fibers may be selected from the group consisting of glass fibers, bar-cut fibers, carbon fibers, aramid fibers, and combinations thereof, and the average diameter of the continuous fibers may be from 5 탆 to 20 탆.

Thermoplastic resin

The thermoplastic resin may include the first thermoplastic resin or the second thermoplastic resin, and the thermoplastic resin is preferably 60 wt% to 80 wt%, but is not limited thereto.

The first thermoplastic resin or the second thermoplastic resin may include the same material or may include different materials. However, when the first thermoplastic resin or the second thermoplastic resin includes the same material, The impregnation property of the second thermoplastic resin composition melted in the continuous fiber film can be further enhanced. The case where the second thermoplastic resin composition contains the same material for further enhancing the impregnation property of the melted second thermoplastic resin composition without the compatibilizing agent means a case where the same kind of resin is contained, It is possible to use any combination of homo, random, and block as long as it includes the base station. Specifically, the first thermoplastic resin may be preliminarily impregnated with a continuous fiber to prepare a continuous fiber film, and it is preferably 1 wt% to 20 wt%, but is not limited thereto. If the content of the first thermoplastic resin is less than the above range, physical properties such as strength and stiffness are not significantly developed, and the physical properties of the composite material are deteriorated. When the content of the first thermoplastic resin exceeds the above range, Is lowered.

The second thermoplastic resin may be added to the first extruder. The second thermoplastic resin is preferably contained in an amount of 60 wt% to 80 wt% excluding the content of the first thermoplastic resin previously introduced to impregnate the continuous fiber in advance. It does not. When the content of the second thermoplastic resin is less than the above range, physical properties such as strength and stiffness are not significantly developed, and the physical properties of the composite material are deteriorated. When the content of the second thermoplastic resin exceeds the above range, D process is difficult to apply.

The first thermoplastic resin or the second thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO) And may include one selected from the group consisting of polyvinyl chloride (PVC), polyethylene terephthalate (PET), nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof .

Specifically, the first thermoplastic resin or the second thermoplastic resin preferably includes polypropylene, but is not limited thereto. At this time, the first thermoplastic resin or the second thermoplastic resin may be used in combination of any one of homo-polypropylene, random-polypropylene, and block-polypropylene .

In particular, the melt index (MFI) of the first thermoplastic resin or the second thermoplastic resin is preferably 1 to 100 g / 10 min, more preferably 10 to 30 g / 10 min. At this time, the melt index Is less than 1 g / 10 min, the thermoplastic resin may easily solidify and the impregnability may be deteriorated. On the other hand, if it exceeds 100 g / 10 min, there is a problem that the thermoplastic resin flows down.

Wherein the first thermoplastic resin composition is a composition comprising a first thermoplastic resin and the second thermoplastic resin composition is a composition comprising a second thermoplastic resin, wherein the first thermoplastic resin composition essentially contains a compatibilizing agent, The second thermoplastic resin composition does not necessarily contain a compatibilizer.

The first thermoplastic resin or the second thermoplastic resin may further comprise at least one additive selected from pigments, antioxidants, heat stabilizers, UV stabilizers and viscosity modifiers. In this case, the additive may further comprise 0.1 to 10 parts by weight based on 100 parts by weight of the first thermoplastic resin or the second thermoplastic resin.

Compatibilizer

The compatibilizing agent may be at least one selected from the group consisting of silane-based, titanate-based, aluminum-based, zirconium-based, borane-based, and mixtures thereof. In order to further enhance the impregnation property of the first thermoplastic resin composition with the continuous fiber, the compatibilizing agent can be produced by putting the continuous fiber, the first thermoplastic resin and the compatibilizing agent into an extruder and melt-kneading the continuous fiber. However, since the first thermoplastic resin composition is already subjected to the surface treatment on the continuous fiber in the continuous fiber film, the second thermoplastic resin composition melted without additional compatibilizer has excellent impregnability to the continuous fiber film, and the bending strength, flexural modulus And excellent tensile properties such as tensile strength and tensile rigidity.

That is, the compatibilizing agent is essentially added to the first thermoplastic resin composition in order to enhance impregnation of the first thermoplastic resin composition into the continuous fiber, but it is not necessarily included in the second thermoplastic resin composition.

The content c of the compatibilizing agent varies depending on how much maleic anhydride in the compatibilizing agent is grafted to the matrix resin. The compatibilizing agent is preferably 0.01 wt% to 20 wt% But is not limited thereto. When the amount of the compatibilizing agent is less than the above range, the impregnation property of the first thermoplastic resin composition to the continuous fiber is deteriorated. When the content of the compatibilizing agent exceeds the above range, physical properties such as strength and stiffness are largely manifested And the physical properties of the composite material are deteriorated.

Continuous Fiber Reinforced Composite

The continuous fiber-reinforced composite material may have a flexural strength of 120 MPa to 140 MPa and a flexural elasticity of 4 GPa to 5 GPa, when the continuous fiber-reinforced composite material is formed of 10 wt% to 20 wt% of glass fibers. The tensile strength may be 80 MPa to 90 MPa, the tensile elastic modulus may be 6 GPa to 7 Gpa, and the elongation may be 1% to 3%.

Therefore, the continuous fiber-reinforced composite material has excellent bending properties such as flexural strength and flexural modulus, and is excellent in tensile properties such as tensile strength and tensile rigidity.

The present invention also provides a method for producing a continuous fiber sheet, comprising the steps of: a) preparing a continuous fiber film impregnated with a first thermoplastic resin composition in continuous fibers; b) injecting and melting the second thermoplastic resin composition into a first extruder; And c) melt-kneading the continuous fiber film prepared in a) and the second thermoplastic resin composition melted in b) into a second extruder and melt-kneading the same, wherein the long fiber reinforced thermoplastic-direct compounding (LFT-D) The present invention also provides a method of producing a continuous fiber reinforced composite material excellent in impregnation property.

The step a) is a step of preparing a continuous fiber film impregnated with the first thermoplastic resin composition in the continuous fiber.

The continuous fiber film may be one obtained by melt-kneading the continuous fiber and the first thermoplastic resin composition.

The first thermoplastic resin composition is a composition comprising a first thermoplastic resin, and the first thermoplastic resin composition essentially contains a compatibilizing agent. At this time, the compatibilizer which is essentially contained in the first thermoplastic resin composition is intended to further improve the impregnation property of the first thermoplastic resin composition in the continuous fiber. The continuous fiber, the first thermoplastic resin and the compatibilizer are put into an extruder, A continuous fiber film can be produced.

The continuous fiber film may be formed by alternately stacking the continuous fibers and the first thermoplastic resin composition layers.

Specifically, the continuous fiber film may be formed by alternately laminating a sheet having a continuous fiber skeleton and a first thermoplastic resin composition sheet, and then melt-pressing the first thermoplastic resin composition sheet so that the first thermoplastic resin composition of the first thermoplastic resin composition sheet penetrates into the continuous fiber structure And the continuous fiber layer is formed by impregnating the continuous fiber layer. As a result, the continuous fiber and the first thermoplastic resin composition can form a continuous fiber layer in which layers are alternately stacked.

In order to impregnate the first thermoplastic resin composition with the continuous fibers of the continuous fiber layer in the production of the continuous fiber film, a first thermoplastic resin composition in the form of a sheet or tape or film as described above may be used. In another example, Type first thermoplastic resin composition may be used.

The melt-pressing can be performed without limitation by a known process. Specifically, a double belt can be used as a heat source for impregnating the continuous thermoplastic resin composition with the first thermoplastic resin composition, and for example, melt compression can be performed by a hot roll method which is a car rendering method.

The degree of impregnation of the first thermoplastic resin composition can be controlled according to process conditions such as temperature and pressure during melt-pressing. The temperature and the duration of the heated part may be controlled so that the impregnation property may be changed depending on the portion of the continuous fiber film.

The total thickness of the continuous fiber layer may be between 20 μm and 65 μm. The continuous fiber layer having a thickness in the above range is suitable for realizing the impregnation property so that the continuous fiber reinforced resin composite material has mechanical strength while imparting appropriate flexibility.

The total thickness of the first thermoplastic resin composition layer may be 10 탆 to 200 탆. The first thermoplastic resin composition layer having a thickness in the above range is suitable for realizing the impregnation property so that the continuous fiber reinforced resin composite material has a mechanical strength while imparting appropriate flexibility.

The fibers may be selected from the group consisting of glass fibers, bar-cut fibers, carbon fibers, aramid fibers, and combinations thereof, and the average diameter of the continuous fibers may be from 5 탆 to 20 탆.

The first thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO), polyvinyl chloride (PVC), polyethylene terephthalate (PET), Nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof.

Specifically, the first thermoplastic resin preferably includes polypropylene, but is not limited thereto. At this time, the first thermoplastic resin may be a mixture of homo-polypropylene, random-polypropylene, and block-polypropylene. Particularly, The melt index (MFI) of the thermoplastic resin is preferably 1 to 100 g / 10 min, more preferably 10 to 30 g / 10 min. When the melt index is less than 1 g / 10 min, the thermoplastic resin easily solidifies, There is a possibility that the thermoplastic resin may be deteriorated. On the contrary, when the amount exceeds 100 g / 10 min, there is a problem that the thermoplastic resin flows down.

The first thermoplastic resin may further include at least one additive selected from pigments, heat stabilizers, UV stabilizers, and viscosity modifiers. In this case, 0.1 to 10 parts by weight of the additive may be added to 100 parts by weight of the first thermoplastic resin.

The step b) is a step of injecting the second thermoplastic resin composition into the first extruder and melting the second thermoplastic resin composition.

The second thermoplastic resin composition is a composition containing a second thermoplastic resin, and the second thermoplastic resin composition does not necessarily contain a compatibilizer.

The second thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO), polyvinyl chloride (PVC), polyethylene terephthalate (PET), Nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof.

Specifically, the second thermoplastic resin preferably includes polypropylene, but is not limited thereto. At this time, the second thermoplastic resin may be a mixture of homo-polypropylene, random-polypropylene, and block-polypropylene.

The melt index (MFI) of the second thermoplastic resin is preferably 1 to 100 g / 10 min, more preferably 10 to 30 g / 10 min. When the melt index is less than 1 g / 10 min, the thermoplastic resin The impregnation property may be deteriorated. On the other hand, when it exceeds 100 g / 10 min, there is a problem that the thermoplastic resin flows down.

The second thermoplastic resin may further comprise at least one additive selected from pigments, heat stabilizers, UV stabilizers and viscosity modifiers. In this case, 0.1 to 10 parts by weight of the additive may be added to 100 parts by weight of the second thermoplastic resin.

And c) the continuous fiber film prepared in a) and the second thermoplastic resin composition melted in b) are put into a second extruder and melted and kneaded.

In the continuous fiber film of the present invention, the first thermoplastic resin composition is surface-treated as a whole on the continuous fiber, so that even if the compatibilizer is not added separately, the melted second thermoplastic resin has excellent impregnability with the continuous fiber film , Flexural strength, flexural modulus, and tensile properties such as tensile strength and tensile rigidity.

Hereinafter, preferred embodiments of the present invention will be described in order to facilitate understanding of the present invention. However, the following examples are provided only for the purpose of easier understanding of the present invention, and the present invention is not limited by the following examples.

[ Example ]

Example  One

97% by weight of a first thermoplastic resin of polypropylene, 2% by weight of a compatibilizer and 1% by weight of an antioxidant were put into an extruder and melted and kneaded at a temperature of 240 ° C to prepare a melted first thermoplastic resin composition. A continuous fiber film was prepared in advance by impregnating 30 wt% of the molten first thermoplastic resin composition with 70 wt% of continuous fiber of glass material at 240 캜.

75 wt% of a second thermoplastic resin made of polypropylene was put into a first extruder and melted at a temperature of 240 캜. A long fiber reinforced thermoplastic (LFT-D) composed of a first extruder and a second extruder was produced by putting 25 wt% of the prepared continuous fiber film and 75 wt% of the molten second thermoplastic resin into a second extruder and melt- - Direct Compounding process to produce continuous fiber reinforced composites with excellent impregnation properties.

Example  2

Instead of 75% by weight of the second thermoplastic resin of polypropylene material of Example 1, a thermoplastic resin composition comprising 72% by weight of a second thermoplastic resin of polypropylene, 2% by weight of compatibilizer and 1% by weight of heat stabilizer 2 fiber reinforced composite material excellent in impregnation property was prepared in the same manner as in Example 1,

Comparative Example  One

A second thermoplastic resin composition containing 72 wt% of a second thermoplastic resin of polypropylene, 2 wt% of a compatibilizer, and 1 wt% of a heat stabilizer was put into a first extruder and melted at a temperature of 240 캜. 25% by weight of general long fiber made of glass and 75% by weight of molten second thermoplastic resin composition were put into a second extruder and melted and kneaded at a temperature of 240 ° C to obtain LFT-D (Long) composed of a first extruder and a second extruder Fiber Reinforced Thermoplastic - Direct Compounding) process.

The continuous fiber-reinforced composites according to Examples 1 and 2 and Comparative Example 1 were formed in the composition ratios shown in Table 1 below.

Composition ratio (% by weight) Example 1 Example 2 Comparative Example 1 Continuous fiber (glass) 17.5 17.5 - General fiber (glass) - - 25 The first thermoplastic resin (PP) 7.275 7.275 - The second thermoplastic resin (PP) 75 72 72 Compatibilizer 0.15 2.15 2 Antioxidant 0.075 0.075 - Heat stabilizer - One One

Experimental Example

One. Flexural strength  And Flexural modulus  evaluation

The flexural strength and flexural modulus of the composites according to Examples 1 and 2 and Comparative Example 1 were measured by UTM using the ASTM D 790 method.

division Example 1 Example 2 Comparative Example 1 Flexural strength
(MPa) 125 135 115 Flexural modulus
(GPa) 4.4 4.5 4.3

Table 2 shows the results of evaluating the flexural strength and flexural modulus of the composite material prepared according to Examples 1 to 2 and Comparative Example 1. [

Referring to Table 2, it can be seen that Examples 1 and 2 using the continuous fiber film in which the first thermoplastic resin composition was impregnated with the continuous thermoplastic resin composition were superior in flexural strength and flexural modulus as compared with Comparative Example 1.

2. The tensile strength  And Tensile modulus  evaluation

The tensile strength and tensile elastic modulus of the composites according to Examples 1 and 2 and Comparative Example 1 were measured using UTM in accordance with ASTM D 638 method.

division Example 1 Example 2 Comparative Example 1 The tensile strength
(MPa) 80 87 70 Tensile modulus
(GPa) 6.3 6.7 6

Table 3 shows the results of evaluating the tensile strength and tensile elastic modulus of the composite material prepared according to Examples 1 to 2 and Comparative Example 1. [

Referring to Table 3, it can be seen that Examples 1 and 2 using the continuous fiber film in which the first thermoplastic resin composition was impregnated with the continuous thermoplastic resin composition were superior in both the tensile strength and the tensile elastic modulus as compared with Comparative Example 1.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive.

Claims (13)

delete delete delete delete delete a) preparing a continuous fiber film impregnated with the first thermoplastic resin composition in the continuous fiber;
b) injecting and melting the second thermoplastic resin composition into a first extruder; And
c) melt-kneading the continuous fiber film prepared in a) and the second thermoplastic resin composition melted in b) into a second extruder,
Wherein the first thermoplastic resin composition contains 0.01 wt% to 2 wt% of a compatibilizing agent, the second thermoplastic resin composition does not contain a compatibilizing agent,
The melt index (MFI) of the first thermoplastic resin and the second thermoplastic resin is 10 g / 10 min to 30 g / 10 min,
Wherein the continuous fiber film is formed by alternately laminating the continuous fibers and the first thermoplastic resin composition layers,
The total thickness of the continuous fiber layer is 20 to 65 占 퐉,
Wherein the total thickness of the first thermoplastic resin composition layer is 10 占 퐉 to 200 占 퐉,
When the continuous fiberglass film is formed by alternately laminating the sheet having the continuous fiber skeleton and the first thermoplastic resin composition sheet and melt-pressing the first thermoplastic resin composition sheet, the first thermoplastic resin composition of the first thermoplastic resin composition sheet is impregnated into the continuous fiber structure Formed
A method for manufacturing a continuous fiber reinforced composite excellent in impregnation property by a long fiber reinforced thermoplastic (LFT-D) process.
delete The method according to claim 6,
The average diameter of the continuous fibers is 5 to 20 占 퐉
A method for producing a continuous fiber reinforced composite excellent in impregnation property.
delete delete delete The method according to claim 6,
Wherein the fibers are selected from the group consisting of glass fibers, bar-cut fibers, carbon fibers, aramid fibers, and combinations thereof
A method for producing a continuous fiber reinforced composite excellent in impregnation property.
The method according to claim 6,
The first thermoplastic resin or the second thermoplastic resin may be at least one selected from the group consisting of polytetrafluoroethylene (PTFE), polyethylene, polypropylene, polystyrene, polyphenylene oxide (PPO) And one selected from the group consisting of polyvinyl chloride (PVC), polyethylene terephthalate (PET), nylon 6.6, polymethyl methacrylate (PMMA), and combinations thereof.
A method for producing a continuous fiber reinforced composite excellent in impregnation property.

Images