JPH11228842A - Thermoplastic resin composition reinforced with long fiber, molding material and molded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a long fiber-reinforced thermoplastic resin molded product scarcely generating the curvature of the molded product and having improved flexural strength and impact strength, to obtain a long fiber-reinforced thermoplastic resin composition suitable for obtaining the long fiber-reinforced thermoplastic resin molded product, to obtain a material for molding the long fiber- reinforced thermoplastic resin and to provide a molded product therefrom. SOLUTION: This long fiber-reinforced thermoplastic resin composition comprises 35-85 wt.% of a thermoplastic resin, 5-50 wt.% of reinforcing fibers having a weight-average fiber length of 3-150 mm, 5-25 wt.% of glass flakes and 5-25 wt.% of a thermoplastic elastomer in a (glass flake)/(thermoplastic elastomer) weight ratio of 0.25-4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a long fiber reinforced thermoplastic resin composition, a long fiber reinforced thermoplastic resin molding material, and a long fiber reinforced thermoplastic resin molded article. More specifically, a long-fiber-reinforced thermoplastic resin molded article having less warpage of a molded article, and having improved bending strength and impact strength, a long-fiber-reinforced thermoplastic resin composition suitable for obtaining the same, and a long-fiber-reinforced heat The present invention relates to a plastic resin molding material.

[0002]

2. Description of the Related Art Long fiber reinforced thermoplastic resin pellets can be produced by passing a continuous reinforcing fiber bundle through a resin impregnating die box such as a crosshead die, followed by cooling and pelletizing. The injection molded product of the pellet exhibits excellent characteristics such as high strength (high bending strength) and high impact resistance, but a large and thin molded product often warps. In order to improve the warpage, a method of adding a plate-like filler (mica, talc, glass flake) (JP-A-6-279615) and a method of adding an elastomer (JP-A-7-53836) are known. When a plate-like filler is added, warpage is suppressed and a material having high bending strength can be obtained, but the impact characteristics are reduced. When an elastomer is added, the warpage is suppressed and a high impact strength is obtained, but the bending strength is significantly reduced. Thus, no well-balanced warpage, bending strength and impact strength have been obtained.

Further, a method of adding mica and an elastomer to a short fiber glass fiber reinforced resin (JP-A-6-8735)
Although 3) is disclosed, since mica is added in a larger amount than glass fiber, the merit of glass fiber reinforcement is small, and the improvement in bending strength and impact strength is smaller than that of long fiber reinforced resin. Further, addition of an elastomer and glass powder to a glass fiber reinforced resin is disclosed (JP-A-59-226041), but the glass powder used here has a columnar shape (having a diameter of 13 μm or less and a length of 5 to 5 μm). 300 μm), whereby the effect of reducing warpage in the long fiber reinforced resin is small and the effect of improving strength is also small. As described above, none of the warpage, bending strength, and impact strength have been improved, and a material that balances these three physical properties has been desired.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a molded article having a small warpage and a good balance of bending strength and impact strength, a composition suitable for molding the same, and a molding material. Aim.

[0005]

The present invention relates to a composition comprising a thermoplastic resin, reinforcing fibers, glass flakes and a thermoplastic elastomer, comprising (glass flake) /
(Thermoplastic elastomer) = 0.25 to 4 (weight ratio), and it was found that a molded article having a small warpage and a good balance of bending strength and impact strength can be obtained by molding this. is there. Further, the glass flakes have an average thickness of 3 to 7 μm and an average area of 200 μm.
It is preferable to use an amorphous plate having a size of 0 μm ² or more.

[0006] That is, the first invention is a thermoplastic resin 3
5 to 85% by weight, 5 to 50% by weight of reinforcing fibers having a weight average fiber length of 3 to 150 mm, 5 to 25% by weight of glass flakes and 5 to 25% by weight of a thermoplastic elastomer,
(Glass flake) / (thermoplastic elastomer) = 0.
A long fiber reinforced thermoplastic resin composition having a weight ratio of 25 to 4 (weight ratio).

A second invention is directed to a fiber-reinforced thermoplastic resin pellet impregnated with a thermoplastic resin in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction, and a thermoplastic resin containing glass flakes. And a thermoplastic elastomer, wherein the weight average length of the reinforcing fibers in the fiber reinforced thermoplastic resin pellets is 3 to 150 mm, and the length of the reinforcing fibers is the fiber reinforced heat. The same as the length of the plastic resin pellets, in the molding material,
It contains 35 to 85% by weight of total thermoplastic resin, 5 to 50% by weight of reinforcing fiber, 5 to 25% by weight of glass flake and 5 to 25% by weight of thermoplastic elastomer, and (glass flake) / (thermoplastic elastomer) = 0 0.25 to 4 (weight ratio) is a material for molding a long fiber reinforced thermoplastic resin.

A fiber reinforced thermoplastic resin pellet in which a thermoplastic resin and a thermoplastic elastomer are impregnated in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction;
A molding material comprising a thermoplastic resin containing glass flakes, in the fiber-reinforced thermoplastic resin pellets, the weight average length of the reinforcing fibers is 3 to 150 mm,
In addition, the length of the reinforcing fiber is the same as the length of the fiber-reinforced thermoplastic resin pellet, and 35 to 85% by weight of the total thermoplastic resin, 5 to 50% by weight of the reinforcing fiber in the molding material,
Containing 5 to 25% by weight of glass flakes and 5 to 25% by weight of a thermoplastic elastomer, (glass flake) /
(Thermoplastic elastomer) = 0.25 to 4 (weight ratio).

The third invention comprises 35 to 85% by weight of a thermoplastic resin, 5 to 50% by weight of reinforcing fibers having a weight average fiber length of 2 mm or more, 5 to 25% by weight of glass flakes and 5 to 25% by weight of a thermoplastic elastomer. A long-fiber-reinforced thermoplastic resin molded product, wherein (glass flake) / (thermoplastic elastomer) = 0.25 to 4 (weight ratio).

Here, in the first, second and third inventions, it is preferable that the glass flakes have an average thickness of 3 to 7 μm and an average area of 2000 μm ² or more. Preferably, the thermoplastic resin is a polyolefin-based resin, the reinforcing fibers are glass fibers, and the thermoplastic elastomer is an olefin-based thermoplastic elastomer.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, second and third embodiments of the present invention will be described below.
The constituent components of the invention will be described. (Thermoplastic resin) Examples of the thermoplastic resin used in the present invention include polyolefin resins such as polyethylene and polypropylene, polyamide resins such as nylon 6 and nylon 66, polyvinyl chloride resins, polystyrene resins, and polyethylene terephthalate. And polyester-based resins such as polybutylene terephthalate, and polycarbonate-based resins. Among these, a polyolefin-based resin is preferable in view of a balance between properties and price. The polyolefin-based resin may be a homopolymer such as ethylene, propylene, butene, 4-methylpentene, or a copolymer thereof, or a modified polypropylene such as acrylic acid or maleic anhydride. One or more of these polyolefin-based resins may be used. Of these, polypropylene is more preferred. The thermoplastic resin used is M
FR 45 to 200 g / 10 min is preferable.

In the first, second and third aspects of the present invention, the thermoplastic resin is contained in an amount of 35 to 85% by weight. 3
If the amount is less than 5% by weight, the dispersion of the resin tends to be non-uniform, and the strength of the obtained molded article decreases. When the content is more than 85% by weight, the amount of reinforcing fibers is small, and the improvement in strength is small. Preferably it is 45 to 75% by weight.

(Reinforcing Fiber) Examples of the reinforcing fiber that can be used in the present invention include glass fiber, carbon fiber, and metal fiber. Among them, glass fiber is preferable from the viewpoint of the balance between characteristics and price. The diameter of the reinforcing fiber is preferably 3 to 40 μm. If it is less than 3 μm, when the same reinforcing fiber content is used, the number of reinforcing fibers relatively increases, so that it becomes difficult to impregnate the resin into the reinforcing fiber bundle, and if it exceeds 40 μm, the surface appearance of the molded product is significantly deteriorated. Optimal reinforcing fiber diameter is 9 ~
25 μm.

In the resin composition of the first invention and the resin-forming material of the second invention, that is, in the raw materials to be charged, the fiber length of the reinforcing fiber is 3 to 150, preferably 5 to 150.
25 mm. Within this range, the resulting molded article has high strength and high impact resistance. Here, the weight average fiber length is an average length obtained by dividing the sum of the weights of the fibers for each length by the total weight. The weight-average fiber length of the reinforcing fibers in the molded article according to the third invention has a smaller average value than the fiber length at the time of mixing the composition or during the molding step. In the first, second, and third inventions of the present invention, the reinforcing fiber is 5 to 50.
% By weight. If it is less than 5% by weight, the bending strength and impact strength will be low, and if it is more than 50% by weight, resin impregnation will be insufficient and the bending strength and impact strength will be low. Preferably, it is 15 to 40% by weight.

[0015] The surface of the reinforcing fiber is preferably treated with a coupling agent. Examples of the coupling agent include silane coupling agents such as aminosilane, epoxysilane, amidosilane, azidosilane, and acrylsilane, and titanate coupling agents. Of these, aminosilane and epoxysilane are preferred, and aminosilane coupling agents are particularly preferred. In addition, the reinforcing fiber may be surface-treated with a surfactant, an antistatic agent or the like in addition to the coupling agent. In the present invention, a continuous reinforcing fiber bundle (roving) in which thousands to tens of thousands of reinforcing fibers are converged.
It is preferably used in the form of

(Glass flakes) Glass flakes are reinforced
Has the effect of softening the anisotropy of the molded body caused by fibers
it is conceivable that. The glass flakes of the present invention are E glass or
Is an amorphous plate-like material such as C glass, having an average thickness of 3 to 7
μm, average area 2000 μm^TwoThe above is preferred. further
Preferably, the average thickness is 4-6 μm and the average area is 7000
200,000 μm ^TwoIt is. Figure 2 shows an amorphous plate
An example of a flake is shown. Glass flake 1 is glass
This glass flake has a surface perpendicular to the flake thickness 3.
The average of the surface area 2 of the work is defined as the average area. Glass frame
When the average thickness and average area of the
Large without warpage without impairing the strength and impact resistance of the molded body
A thin molded article is obtained.

The surface of the glass flake is preferably treated with a coupling agent. Examples of the coupling agent include silane coupling agents such as amino silane, epoxy silane, amido silane, azido silane, and acryl silane, and titanate coupling. Of these, aminosilane and epoxysilane are preferred, and aminosilane coupling agents are particularly preferred. The glass flakes may be surface-treated with a surfactant, an antistatic agent, or the like in addition to the coupling agent. The amount of glass flake added is 5 to 25% by weight in the first, second and third inventions.
It is. Within this range, the bending strength, impact strength, and warpage are well balanced.

The ratio of the glass flakes to the thermoplastic elastomer is (glass flake) / (thermoplastic elastomer) = 0.25-4, preferably 0.5-2.
(Weight ratio). When the ratio exceeds 4, the rigidity is improved, but the impact resistance is reduced. On the other hand, when the ratio is less than 0.25, the impact resistance is improved, but the strength and rigidity are significantly reduced. By blending the glass flakes and the elastomer in a specific ratio, the obtained molded article was found to have a small warp and to have sufficient bending strength and impact strength, and completed the present invention. Further, for unknown reasons, it has been found that the strength of the glass flake and elastomer added at the ratio of the present invention is higher than the bending strength expected when glass flake and elastomer are added alone. As a method for adding glass flakes, a method in which kneaded in advance with a thermoplastic resin such as a polypropylene resin or the like to form a master batch pellet and dry blend with a long fiber reinforced resin pellet is preferable in terms of handling.

(Thermoplastic Elastomer) The thermoplastic elastomer is not particularly limited.
Olefin-based thermoplastic elastomers such as α-olefin copolymer, polyethylene-based such as ethylene / styrene-based, and polypropylene-based such as propylene / olefin-based copolymer are preferred. Among these, polypropylene is preferable from the balance of properties such as strength and heat resistance, and examples thereof include ethylene-propylene copolymer, propylene-butene copolymer, ethylene-propylene-diene copolymer and the like. It is considered that the thermoplastic elastomer is dispersed in the thermoplastic resin in an island shape and has a function of alleviating internal strain during molding.

5 to 25% by weight of the thermoplastic elastomer
Contained. If the amount of the thermoplastic elastomer is less than 5% by weight, the resulting molded article is inferior in impact resistance and 25% by weight.
If it is too high, the strength is inferior. The method of adding the elastomer is
As a masterbatch pellet after kneading in a polypropylene resin or the like, a method of dry blending with a long-fiber reinforced pellet, a method of mixing in a matrix resin at the time of producing a long-fiber reinforced resin pellet, and the like can be mentioned.

(Long Fiber Reinforced Thermoplastic Resin Composition, Molding Material) The composition of the first invention comprises thermoplastic resins 35 to 85.
Weight%, reinforcing fiber having a weight average fiber length of 3 to 150 mm
50% by weight, 5 to 25% by weight of glass flakes and 5 to 25% by weight of thermoplastic elastomer, (glass flake) / (thermoplastic elastomer) = 0.25 to 4
(Weight ratio) is a long fiber reinforced thermoplastic resin composition. This resin composition is not limited as long as the above-mentioned components are in the specified amount ranges, and a mixture of each component is prepared by forming a specific pellet and then mixing with other components. But more preferably,
A composition obtained by using the molding material of the following (1) or (2) and adding a thermoplastic resin as necessary to adjust the composition to the composition range of the first invention is preferable.

(1) (a) A fiber reinforced thermoplastic resin pellet impregnated with a thermoplastic resin and (b) glass flakes are contained in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction. Molding Material Containing Thermoplastic Resin and (c) Thermoplastic Elastomer When the molding material of (1) is used, the reinforcing fibers are provided in pellets in which the thermoplastic resin is impregnated in the reinforcing fiber bundle, and the The strength, rigidity, impact strength, etc. of the molded article obtained are high.
Further, since the glass flakes are provided by being mixed into the thermoplastic resin, the handling is easy and the glass flakes are not easily damaged in the manufacturing process of the molded article.

(2) (d) Fiber reinforced thermoplastic resin pellets impregnated with a thermoplastic resin and a thermoplastic elastomer, and (b) glass flakes, in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction. Molding material containing thermoplastic resin contained When the molding material of (2) is used, the thermoplastic elastomer is provided in the form of pellets previously impregnated into the reinforcing fiber bundle together with the thermoplastic resin. The dispersion of the thermoplastic elastomer becomes more uniform, the warpage is small, and the impact strength tends to be high.

Hereinafter, the molding material of (1) or (2) of the second invention will be described. (Regarding the molding material (1)) The fiber-reinforced thermoplastic resin pellet (a) may be any one in which a thermoplastic resin is impregnated in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction. . The method for producing the pellets is not particularly limited, but a preferred production method is a method of cutting a continuous fiber bundle impregnated with a thermoplastic resin.

Any method may be used for impregnating the continuous fiber bundle with the thermoplastic resin. For example, a method of impregnating a reinforcing fiber bundle with an emulsion of a thermoplastic resin, applying a coating, and then drying a powder suspension of the thermoplastic resin to the reinforcing fiber bundle,
After drying, heat-melting and impregnating the method.The reinforcing fiber bundle is charged, a thermoplastic resin powder is adhered, and then the method of heat-melting and impregnating is performed. After impregnating the reinforcing fiber bundle with the thermoplastic resin dissolved in the solvent,
Method of Removing Solvent Any method such as a method of impregnating a heated and melted thermoplastic resin while opening a reinforcing fiber bundle on a bar, a roll, or a die (drawing method) may be used.

Among these methods, a method (pull-out method) of impregnating a thermoplastic resin melted by heating with a bar, a roll, or a die while opening a reinforcing fiber bundle is most preferable because of simplicity of an apparatus and a process. . In the thus obtained pellet after cutting, the reinforcing fibers are present in a state of being substantially the same length as the pellet and aligned in the fiber length direction.

The weight average length of the pellets is 3 to 150.
mm. If it is less than 3 mm, the length of the reinforcing fibers in the molded article becomes short, and the strength, particularly the impact strength, is reduced. 150
If it exceeds mm, the effect on high strength and high impact, which are the features of long fiber reinforcement, becomes inconspicuous, and clogging occurs in the hopper during molding. The preferred pellet length is 5 to 25 mm. The shape of the pellet is
Any shape may be used as long as the length is 3 to 150 mm. For example, the cut surface may be circular, elliptical, or square. The length of the cut surface in the longitudinal direction is preferably such that the aspect ratio (the ratio of the length of the pellet to the length of the cut surface) is 0.1 to 10, more preferably 0.2 to 5.

The amount of the reinforcing fibers in the pellets is preferably 20 to 80 wt%, more preferably 40 to 65 wt%.
%. This is because in this range, the reinforcing fiber bundle is excellent in the impregnation property of the thermoplastic resin. The thermoplastic resin (b) containing glass flakes may be a resin containing glass flakes in the thermoplastic resin, and can be produced by a usual melt-kneading method using an extruder, a kneader or the like.

The thermoplastic resin (b) containing glass flakes may be used in a molten state, but has an average length of 1 to 5
It is preferably used as a pellet of mm. Preferably, the average length is 2 to 4 mm. The cross-sectional shape of the pellet may be any shape, for example, the cut surface may be circular, elliptical, or square. Also, a circular or elliptical one having an average particle diameter of 1 to 5 mm may be used. The content of the glass flakes in (b) is preferably 20 to 80 wt%, more preferably 40 to 60 wt%. Within this range, it is easy to disperse uniformly, and the balance between bending strength and warpage is excellent.

The thermoplastic elastomer may be used alone, or may be used by previously containing a thermoplastic elastomer in a thermoplastic resin. When the melting point of the thermoplastic elastomer is low (for example, 60 ° C. or less), handling is easier if the thermoplastic elastomer is previously contained in the thermoplastic resin. When used alone, the thermoplastic elastomer (c) is preferably used as a pellet having an average length of 1 to 5 mm, or a circle or an ellipse having an average particle size of 1 to 5 mm, and the cross-sectional shape of the pellet is not particularly limited. Thermoplastic resin containing thermoplastic elastomer (c ')
May be used as long as the thermoplastic resin contains the thermoplastic elastomer, and a usual melt-kneading method using an extruder, a kneader, or the like can be manufactured.

The thermoplastic resin (c ′) containing the thermoplastic elastomer may be used in a molten state, but may be used as pellets having an average length of 1 to 5 mm, or a circle having an average particle size of 1 to 5 mm or an ellipse. It is preferably used, and the cross-sectional shape of the pellet is not particularly limited. The content of the thermoplastic elastomer in (c ′) is preferably 10 to 45 wt%.
In this range, the thermoplastic elastomer is dispersed in the thermoplastic resin matrix, so that the obtained molded article is excellent in balance between bending strength and impact strength. If necessary, a thermoplastic resin pellet (e) may be added to these (a), (b), (c) and (c ′).

The shape and size of the thermoplastic resin (e) are not particularly limited, but are preferably used as pellets having an average length of 1 to 5 mm, or circular or elliptical having an average particle size of 1 to 5 mm. The amounts of (a), (b) and (c) are not particularly limited as long as the composition finally obtained is within the composition range of the first invention, but preferably (a), (b) and (c). ),
(E) 40 to 60:10 to 40:10 to 50: 0 to 6
0 wt%, or (a), (b), (c ′), (e)
0 to 60:10 to 40:10 to 50: 0 to 40 wt%.

(Regarding the molding material (2)) Fiber-reinforced thermoplastic resin pellets (d) in which a thermoplastic resin and a thermoplastic elastomer are impregnated in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction. Is obtained in the same manner as in the above (a), and the weight average length and shape of the pellets, and the preferred range of the amount of reinforcing fibers in the pellets are also the same. However,
The pellet (d) contains a thermoplastic elastomer together with a thermoplastic resin. Further, the amount of the thermoplastic elastomer in the pellet is preferably set to 10 to 45% by weight of the whole pellet.

The thermoplastic resin (b) containing glass flakes may be the same as described above. A thermoplastic resin pellet (e) may be further added to these (d) and (b). The amounts of (d) and (b) are as follows: 35 to 85% by weight of total thermoplastic resin, 5 to 50% by weight of reinforcing fiber, 5 to 25% by weight of glass flake, and 5 to 25% by weight of thermoplastic elastomer in the molding material. % (Glass flake) / (thermoplastic elastomer) = 0.25
4 (weight ratio) The finally obtained composition may be within the composition range of the first invention, but preferably (b) and (d) are 15 to 25:35:65 wt%, and (d) , (B),
(E) is set to 15 to 25:35 to 65:10 to 50 wt%.

(Long Fiber Reinforced Thermoplastic Resin Molded Article) The long fiber reinforced thermoplastic resin composition of the present invention, preferably, a molding material is melt-molded to obtain a long fiber reinforced thermoplastic resin molded article as a molded article. be able to. Examples of the melt molding method include injection molding and extrusion molding, and preferably injection molding. The reinforcing fiber length in the molded body is 2 mm or more in weight average. Preferably it is 2 to 9 mm. When the weight average fiber length is less than 2 mm, the bending strength,
Impact strength decreases.

The long-fiber-reinforced thermoplastic resin molded article of the present invention has a small warpage and is excellent not only in bending strength but also in impact strength. Further, within the range where the object of the present invention is not impaired, in the long fiber reinforced thermoplastic resin composition, the molding material and the molded article, an antioxidant, a heat stabilizer, a pigment, a colorant, an ultraviolet absorber, light Stabilizers, lubricants, flame retardants,
Various additives such as release agents, inorganic and organic fillers, and antistatic agents can be added.

[0037]

The present invention will be further described below with reference to examples. The evaluation method is as follows. Method for evaluating physical properties of molded article, reinforcing fiber length, glass flake (1) Flexural strength; in accordance with ASTM D-790. (2) Izod impact strength; based on ASTM D256. (3) Measurement of warpage amount A flat molded body of 120 × 120 × 2 mm was injection-molded,
After the condition was adjusted for 8 hours or more (23 ° C., relative humidity 50%), the molded body was allowed to stand on a surface plate, and the warpage was measured. Measurements were taken at a total of 5 points at the four corners of the flat plate and the edge on the side opposite to the gate, and totaled. The measurement was repeated for five plates in the same lot, and the average value of the total of five points was defined as the amount of warpage.

(4) Reinforcing Fiber Length The sample was fired in air at 600 ° C. for 2 hours, observed with a magnifying glass, and the weight average fiber length was measured. (5) Average Area and Thickness of Glass Flake The sample was fired in air at 600 ° C. for 2 hours, observed with a magnifier, and the average area and average thickness were measured.

(Example 1) A long fiber reinforced thermoplastic resin pellet (a), a thermoplastic resin pellet containing glass flakes (b), and a thermoplastic resin pellet containing a thermoplastic elastomer (c ') were prepared as follows. Manufactured. Next, these three types of pellets and polypropylene pellets (e) were dry-blended to have the composition shown in Table 1, and then a flat plate and a strength test piece were injection-molded. The evaluation results are shown in FIG.
Shown in

Method for producing long fiber reinforced thermoplastic resin pellets (a); Continuous fiber reinforced glass fiber bundle is drawn out by using an impregnation die for drawing, whereby long fiber reinforced thermoplastic resin having a glass fiber (GF) content of 50 wt% is obtained. Pellets were made. Glass roving with fiber diameter of 16μm is 900
Using the zero-converged one, it was cut into a pellet length of 6 mm. MFR = 80g / 10m as matrix resin
In polypropylene (PP) was used. Microscopic observation of the cross section in the length direction of the pellet revealed that the glass fibers were aligned in the fiber length direction, and the length of the glass fiber was the same as that of the pellet. When the cross section of the pellet was observed with a microscope, it was found that the glass fiber bundle was impregnated with the thermoplastic resin.

Method for producing glass flake-containing thermoplastic resin pellet (b): A mixture of PP and glass flake (manufactured by Nippon Sheet Glass) (glass flake: 50 wt%) was kneaded by a twin-screw extruder. Method for producing thermoplastic elastomer-containing thermoplastic resin pellet (c '); produced by kneading a mixture of PP and propylene-based thermoplastic elastomer (manufactured by Mitsui Petrochemicals) (containing 40 wt% of thermoplastic elastomer) with a twin-screw extruder. .

(Examples 2, 3 and Comparative Examples 1 to 4) A molded body was molded and evaluated in the same manner as in Example 1 except that the ratio of the glass flakes to the thermoplastic elastomer was changed. The composition is shown in Table 1. FIG. 1 shows the measurement results of the bending strength, the Izod impact strength, and the warpage.

(Examples 4 to 11, Comparative Examples 5 to 7) Table 2 shows the amounts of thermoplastic resin, the amount of reinforcing fibers, and the types of glass flakes.
A molded body was molded and evaluated in the same manner as in Example 1 except that the temperature was changed as described above. Bending strength, Izod impact strength,
Table 2 shows the measurement results of the warpage.

Example 12 A long-fiber-reinforced thermoplastic resin pellet (d) containing a propylene-based thermoplastic elastomer and a thermoplastic resin pellet (b) containing glass flake were produced as follows. Next, these two types of pellets and polypropylene pellets were dry-blended to have the composition shown in Table 2, and then a flat plate and a strength test piece were injection-molded. Table 2 shows the evaluation results.

Method for producing long fiber reinforced thermoplastic resin pellets (d): A continuous fiber reinforced glass fiber bundle is drawn out using an impregnation die for drawing, whereby a long fiber reinforced resin pellet (polypropylene 30 wt%, GF content 50 wt%, Thermoplastic elastomer 20wt%, glass fiber 50wt
%). The glass roving has a fiber diameter of 16
Pellets of 6 μm were converged by 9000 pieces and were cut into pellet lengths of 6 mm. MF as matrix resin
R = 80 g / 10 min polypropylene (PP) and propylene-based thermoplastic elastomer were used. Microscopic observation of the cross section in the length direction of the pellet revealed that the glass fibers were aligned in the fiber length direction, and the length of the glass fiber was the same as that of the pellet. When the cross section of the pellet was observed with a microscope, it was found that the resin was impregnated in the glass fiber bundle. Production method of glass flake-containing thermoplastic resin pellet (b): produced by kneading a mixture of PP and glass flake (manufactured by Nippon Sheet Glass) (glass flake 50 wt%) with a twin-screw extruder.

[0046]

[Table 1]

[0047]

[0048]

[Table 2]

[0049] (Note 1) Mica: average thickness 4μm average area 22500Myuemu ² of the plate (2) milled fiber: average diameter 13 .mu.m, the average length 300μm cylindrical

[0050]

According to the present invention, a molded article formed by using the composition and the molding material of the present invention has a small warp of the molded article and a good balance of bending strength and impact strength.

[Brief description of the drawings]

FIG. 1 is a graph showing changes in bending strength and Izod impact strength when the ratio of glass flakes to thermoplastic elastomer is changed.

FIG. 2 is a perspective view of a typical glass flake.

[Explanation of symbols]

 1 Glass flake 2 Surface area of glass flake 3 Thickness of glass flake

Claims (10)

[Claims] 1. A thermoplastic resin comprising 35 to 85% by weight, 5 to 50% by weight of reinforcing fibers having a weight average fiber length of 3 to 150 mm, 5 to 25% by weight of glass flakes and 5 to 25% by weight of a thermoplastic elastomer, (Glass flake) / (thermoplastic elastomer) = 0.
A long fiber reinforced thermoplastic resin composition having a weight ratio of 25 to 4 (weight ratio). 2. The glass flake has an average thickness of 3 to 7 μm.
^2. The long fiber reinforced thermoplastic resin composition according to claim 1, wherein the composition is an amorphous plate having an average area of 2,000 μm ² or more. 3. The method according to claim 1, wherein the thermoplastic resin is a polyolefin resin, the reinforcing fibers are glass fibers, and the thermoplastic elastomer is an olefin thermoplastic elastomer. Long fiber reinforced thermoplastic resin composition. 4. A fiber reinforced thermoplastic resin pellet impregnated with a thermoplastic resin in a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction; a thermoplastic resin containing glass flakes; A molding material containing an elastomer, wherein the weight average length of the reinforcing fibers in the fiber-reinforced thermoplastic resin pellets is 3 to 150 mm, and the reinforcing fibers have a length of the fiber-reinforced thermoplastic resin pellets. The molding material contains 35 to 85% by weight of a total thermoplastic resin, 5 to 50% by weight of reinforcing fibers, 5 to 25% by weight of glass flakes, and 5 to 25% by weight of a thermoplastic elastomer in the molding material. , (Glass flake) / (thermoplastic elastomer) = 0.
A material for molding a long fiber reinforced thermoplastic resin, which has a weight ratio of 25 to 4 (weight ratio). 5. A thermoplastic fiber bundle comprising a reinforcing fiber bundle in which reinforcing fibers are aligned in the fiber length direction, a fiber-reinforced thermoplastic resin pellet impregnated with a thermoplastic resin and a thermoplastic elastomer, and a thermoplastic resin containing glass flakes. A molding material containing a resin, wherein the weight average length of the reinforcing fibers in the fiber reinforced thermoplastic resin pellets is 3 to 150 mm, and the length of the reinforcing fibers is the fiber reinforced thermoplastic resin pellet. And the molding material contains 35 to 85% by weight of a total thermoplastic resin, 5 to 50% by weight of reinforcing fibers, 5 to 25% by weight of glass flakes, and 5 to 25% by weight of a thermoplastic elastomer. (Glass flake) / (thermoplastic elastomer) = 0.
A long-fiber-reinforced thermoplastic tree-forming material having a weight ratio of 25 to 4 (weight ratio). 6. The glass flake has an average thickness of 3 to 7 μm.
The long fiber reinforced thermoplastic resin molding material according to any one of claims 4 and 5, wherein the m is an amorphous plate having an average area of 2000 µm ² or more. 7. The method according to claim 4, wherein said thermoplastic resin is a polyolefin resin, said reinforcing fibers are glass fibers, and said thermoplastic elastomer is an olefin thermoplastic elastomer. 2. The material for molding a long fiber reinforced thermoplastic resin according to the item 1. 8. A thermoplastic resin comprising 35 to 85% by weight, 5 to 50% by weight of reinforcing fibers having a weight average fiber length of 2 mm or more, 5 to 25% by weight of glass flakes and 5 to 25% by weight of a thermoplastic elastomer, (Glass flake) / (thermoplastic elastomer) = 0.
A long fiber-reinforced thermoplastic resin molded product having a weight ratio of 25 to 4 (weight ratio). 9. The glass flake has an average thickness of 3 to 7 μm.
m, long fiber-reinforced thermoplastic resin molded article according It is amorphous platelet is the average area 2000 .mu.m ² or to claim 8, wherein. 10. The method according to claim 8, wherein the thermoplastic resin is a polyolefin resin, the reinforcing fibers are glass fibers, and the thermoplastic elastomer is an olefin thermoplastic elastomer. Long fiber reinforced thermoplastic resin molding.