JPH0641389A - Fiber-reinforced polypropyrene composition - Google Patents

Abstract

PURPOSE:To provide the fiber-reinforced polypropylene composition, excellent in mechanical strength such as rigidity and impact resistance and heat resistance without emitting an offensive smell in processing by blending a polypropylene- based resin containing a specific modified polypropylene with a carbon fiber. CONSTITUTION:The composition is obtained by blending (A) polypropylene-based resin containing 2wt.% or more modified polypropylene prepared by carrying out the graft polymerization of 0.1-15 pts.wt. unsaturated glycidyl compound of the formula [R is H or 1-6C alkyl; Ar is 6-20C aromatic hydrocarbon having glycidyloxy; (n) is 1-4] with 100 pts.wt. polypropylene with (B) 5-70 pts.wt. carbon fiber (preferably having 0.5-50mm fiber length and 10-20mum diameter). The modified polypropylene is obtained by a method for charging, e.g. the compound of the formula and polypropylene together with a catalyst into a twin-screw extruder and melt kneading the resultant mixture at 180-250 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to interior and exterior parts for automobiles,
The present invention relates to a fiber-reinforced polypropylene composition suitable as an industrial material for home electric appliances, electric components and the like.

[0002]

2. Description of the Related Art Polypropylene resins are lightweight, have excellent moldability, and have good mechanical properties such as mechanical strength, insulation, and chemical resistance. , Or widely used in various industrial fields such as housings. The mechanical strength of such polypropylene-based resin, and carbon fibers have been compounded for the purpose of further improving the electrical conductivity, but since the polypropylene-based resin does not have good adhesion with the carbon fibers, it is simply Sufficient mechanical properties cannot be obtained only by kneading both.

Therefore, in order to improve the adhesion between the carbon fiber and the polypropylene resin, for example, a composition containing a modified polypropylene grafted with an acid anhydride such as maleic anhydride (JP-A-55-50041). , No. 58-113239),
Composition using urethane-modified epoxy resin and carbon fiber surface-treated with epoxy resin (JP-A-61-252371)
However, since the adhesiveness and dispersibility between polypropylene and carbon fiber are not good, there is a problem in fluidity, and moldability and mechanical properties are insufficient.

Further, the conventional acid anhydride-modified composition has a problem that the acid anhydride vaporizes or decomposes at a high temperature to generate an irritating odor. Therefore, an object of the present invention is to uniformly mix carbon fibers in a polypropylene resin with good adhesiveness, control of fluidity can be easily performed, mechanical properties are improved, and no abnormal odor is generated during molding processing. To provide a resin.

[0005]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors in view of the above problems, a polypropylene resin containing a modified polypropylene obtained by graft-polymerizing a specific unsaturated glycidyl compound and a carbon fiber The inventors have found that the composition is excellent in mechanical strength such as rigidity and impact resistance and heat resistance, and that there is no problem of generating an offensive odor during molding, and thus reached the present invention. That is, the present invention provides (a) the following general formula (I)

[0006]

[Chemical 2]

(In the formula, R represents a hydrogen atom or a carbon number of 1 to 6)
Represents an alkyl group, and Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms and having at least one glycidyloxy group, and n is an integer of 1 to 4. ) Polypropylene resin 100 containing modified polypropylene obtained by graft-polymerizing 0.1 to 15 parts by weight of an unsaturated glycidyl compound represented by the formula (1) to 100 parts by weight of polypropylene.
The fiber-reinforced polypropylene composition is characterized by containing (b) 5 to 70 parts by weight of carbon fiber with respect to parts by weight.

The fiber-reinforced polypropylene composition of the present invention will be described in detail below. In the present invention, the polypropylene serving as the base of the component (a) is a homopolymer of propylene, or a copolymer of propylene containing ethylene or α-olefin having 4 or more carbon atoms up to about 40% by weight. Coalesce, and mixtures thereof.

Such propylene is usually 0.1 to 200
Melt flow rate of about g / 10 minutes (MFR, JISK72
Those having a load of 2.16 kg and a temperature of 230 ° C.) are preferable. When the MFR is less than 0.1 g / 10 minutes, the carbon fiber reinforced polypropylene composition obtained has poor moldability, and
If it is 00 g / 10 minutes or more, the impact resistance is lowered. Also,
As the propylene as a raw material of the modified propylene contained in the component (a), in addition to the polypropylene as the base of the component (a), the following general formula (II)

[0010]

[Chemical 3]

(Wherein R ^{1 to} R ⁴ are hydrogen atoms or alkyl groups having 1 to 6 carbon atoms, and m is an integer of 1 to 20) and a propylene random copolymer containing a conjugated diene comonomer. Polymers can also be used.

In the present invention, the modifier used for modifying the polypropylene resin is represented by the above general formula (I) having a (meth) acrylamide group and an epoxy group in the molecule, and such a modifier is used. The agent is, for example,
It can be produced by the method disclosed in 60-130580. Among the unsaturated glycidyl compounds represented by the above general formula, especially the following general formula (III)

[0013]

[Chemical 4]

(In the formula, R has the same meaning as described above.)
An unsaturated glycidyl compound represented by is preferable.

The unsaturated glycidyl compound-modified polypropylene used in the present invention can be produced by a solution method or a melt-kneading method. In the case of the solution method, for example, polypropylene, the above-mentioned unsaturated glycidyl compound, and a catalyst are dissolved in an organic solvent such as xylene, and modification is carried out at a temperature of 90 to 200 ° C. for 0.1 to 100 hours with stirring.

In the case of the melt-kneading method, the above-mentioned starting materials and catalysts are put into a twin-screw extruder or the like to obtain 170 to 30.
Melt kneading at 0 ° C, preferably 180 to 250 ° C. The modification by the melt-kneading method can be carried out at the time of melt-kneading in which the carbon fiber as the component (b) is blended, as described later. In any modification method, a usual radical initiator as a catalyst, for example, benzoyl peroxide, lauroyl peroxide, di-t-butyl peroxide, acetyl peroxide, t-butyl perbenzoate, dicumyl peroxide, Organic peroxides such as t-butyl hydroperoxide and azo compounds such as azobisisobutyronitrile and azobisamidinopropane can be used. The catalyst is required to be about 0.06 to 20 parts by weight with respect to 100 parts by weight of the unsaturated glycidyl compound for modification.

The mixing ratio of polypropylene and unsaturated glycidyl compound is 0.1 to 15 parts by weight, preferably 0.1 to 100 parts by weight of polypropylene, and preferably 0.1.
2 to 10 parts by weight. The blending ratio of the glycidyl compound is
If it is less than 0.1 part by weight, the graft ratio is low and the effect of modification is insufficient, and if it is 15 parts by weight or more, the molecular weight of the modified polymer obtained is lowered.

In the present invention, the above-mentioned modified polypropylene is blended in polypropylene in an amount of 2% by weight or more. That is, the present invention includes a composition in which all of the component (a) is a modified polypropylene, but the preferred content of the modified polypropylene is 2 to 100% by weight, particularly 5 to 100% by weight. When the proportion of the modified polypropylene is less than 2% by weight, the adhesiveness with the carbon fiber is insufficient, and thus the mechanical strength and heat resistance of the resulting composition are insufficient.

As the carbon fiber (b) used in the present invention, rayon type carbon fiber, PAN (polyacrylonitrile) type carbon fiber, mesophase pitch type carbon fiber and the like are used. Carbon fiber has a fiber length of 0.1 to 100 mm, especially
0.5-50 mm, diameter 5-30 μm, especially 10-20 μm
Are preferred.

Further, in order to further improve the adhesiveness with the polypropylene resin, carbon fibers surface-treated can be used. The content of the carbon fiber (b) is 5 to 70 parts by weight, preferably 10 to 50 parts by weight, based on 100 parts by weight of the polypropylene resin. When the content is less than 5 parts by weight, the mechanical strength and heat resistance of the resulting composition are not sufficiently improved, and when the content is 70 parts by weight or more, the moldability is deteriorated and it becomes difficult to produce a molded product. The strength also decreases.

In the composition of the present invention, for the purpose of further strengthening or modifying it, other than the above-mentioned components, other fillers and reinforcing agents, heat stabilizers, antioxidants, light stabilizers, flame retardants, plasticizers. Further, an antistatic agent, a release agent, a foaming agent, a nucleating agent and the like can be added. Next, a method for producing a carbon fiber reinforced polypropylene composition using each of the above components will be described.

The carbon fiber reinforced polypropylene composition of the present invention comprises a first method of melt kneading polypropylene previously modified with an unsaturated glycidyl compound with carbon fiber and other optional components, and an unmodified polypropylene and a modifier (unmodified). The saturated glycidyl compound), carbon fiber, and other optional components may be added with a catalyst and melt-kneaded to produce the second method.

In the first method, polypropylene, modified polypropylene, carbon fibers are mixed in a predetermined ratio with a single-screw extruder, a twin-screw extruder, a Banbury mixer, a kneading roll, a brabender, a kneader, or the like, or a Henschel mixer. -Supplied to a kneader such as 170-300 ° C., preferably 18
It can be performed by heating and melting at 0 to 250 ° C.

In the second method, the unsaturated glycidyl compound (0.1 parts) is added to 100 parts by weight of unmodified polypropylene.
Biaxially 1 to 15 parts by weight, preferably 0.5 to 10 parts by weight, peroxide 0.01 to 5 parts by weight, preferably 0.1 to 1 part by weight, carbon fiber 5 to 70 parts by weight, preferably 10 to 50 parts by weight. 170-300 degreeC using an extruder etc., Preferably 1
It is carried out by melt-kneading at 80 to 250 ° C.

The carbon fibers may be dry blended with polypropylene pellets in advance, or may be supplied.
Alternatively, when kneading is performed using an extruder, polypropylene and the unsaturated glycidyl compound may be dry-blended and then fed from the middle of the extruder using a gravimetric feeder or the like. According to the second method, the independent polypropylene modification step is omitted, and the polypropylene, the modifier and the carbon fiber are only melt-kneaded together, and the carbon fiber-reinforced polypropylene composition is efficiently modified while modifying the polypropylene. Can be manufactured.

[0026]

As described above, the composition of the present invention is a carbon fiber reinforced polypropylene composition containing a polypropylene resin containing 2% by weight or more of polypropylene modified with a specific unsaturated glycidyl compound and carbon fiber. In addition, the mechanical strength and heat resistance of polypropylene resin are significantly improved, and no offensive odor is generated during molding. The reason why such an effect is obtained by the composition of the present invention is not always clear, but the dispersibility and adhesiveness of carbon fiber in polypropylene are improved by the action of the (meth) acrylic acid group and the epoxy group of the modified polypropylene. It is considered that the fluidity of the carbon fiber reinforced polypropylene is easily controlled.

[0027]

The present invention will be described in detail with reference to the following examples and comparative examples. The following resins were used as raw material resins in each of the examples and comparative examples. Polypropylene (1) Propylene homopolymer [J205, manufactured by Tonen Chemical Co., Ltd., melt flow rate (MFR, 230 ° C, 2.
16 kg load) 5 g / 10 minutes], (2) Propylene homopolymer [J209, manufactured by Tonen Kagaku KK, melt flow rate (MFR, 230 ° C, 2.16 kg load) 9 g / 10 minutes].

Carbon fiber CF: M-107T [Kureha Chemical Co., Ltd., fiber length 0.70 m
m, average fiber diameter 18.0 μm]. Denaturing monomer AXE: a glycidyl compound represented by the following general formula [Kanefuchi Chemical Industry Co., Ltd.].

[0029]

[Chemical 5]

MAH: Maleic anhydride. Radical generator POX: Perhexin-25B [manufactured by NOF CORPORATION]. Modified polypropylene (1) Modified PP-1: Polypropylene (Tonen Chemical Co., Ltd.)
Made; Y201) 100 parts by weight, AXE 2 parts by weight and POX
0.1 part by weight is dry blended with a Henschel mixer and then at Labostomill at 230 ° C. for 5 minutes at 80 rp
Melt flow rate (MFR, 230 ° C, 2.16 kg load) obtained by melt-kneading at m and graft polymerizing 24 g / 1
0 minutes, AXE-modified polypropylene with an AXE graft ratio of 1.8% by weight.

The AXE graft ratio of the modified polypropylene was determined by the following method. The modified polypropylene was dissolved in boiling xylene, precipitated in methanol, the precipitated polymer was vacuum dried, and this was hot pressed into a film having a thickness of about 50 μm. The infrared absorption spectrum of this film was measured and the absorption peak (1648 cm) due to the expansion and contraction of the carbonyl (C = O) bond of the modifier was measured.
^-1 ) and the absorption peak (840 cm ^-1 ) peculiar to isotactic polypropylene were obtained and calculated from a calibration curve prepared in advance.

(2) Modified PP-2: 1,9 decadiene
100 parts by weight of 0.4 mol% copolymerized propylene-non-conjugated diene random copolymer, 2 parts by weight of AXE and POX.
1 part by weight is dry blended with a Henschel mixer, then at Labostomill at 230 ° C. for 5 minutes at 80 rp
Melt flow rate (MFR, 230 ° C., 2.16 kg load) 19 g / 1 obtained by melt-kneading at m and graft polymerization
0 minutes, AXE-modified polypropylene with an AXE graft ratio of 1.8% by weight.

(3) Modified PP-3: 100 parts by weight of polypropylene (manufactured by Tonen Kagaku KK; Y201), 5 parts by weight of MAH and 0.1 part by weight of POX were dry blended with a Henschel mixer, and then 230 ° C. with a Labostomill. MAH-modified polypropylene having a melt flow rate (MFR, 230 ° C., 2.16 kg load) of 113 g / 10 minutes and a MAH graft ratio of 0.5% by weight, which was obtained by melt-kneading at 80 rpm for a minute. The MAH graft ratio was determined by dissolving the modified polypropylene in boiling xylene, precipitating the dissolved components with acetone, and pressing the resulting mixture to a thickness of about 50 μm, and measuring the IR spectrum of the product.
1780c due to expansion and contraction of carbonyl (C = O) bond of AH
It was calculated from the absorbance ratio between around m ^{−1 and} around 840 cm ⁻¹ cm of polypropylene.

(4) Modified PP-4: 1,9 decadiene
100 parts by weight of 0.4 mol% copolymerized propylene-non-conjugated diene random copolymer, 5 parts by weight of MAH and POX.
Melt flow rate (MFR, 230 ° C., 2.16 kg load) 115 g / 10 obtained by dry blending 1 part by weight with a Henschel mixer, and melt-kneading at 80 ° C. for 5 minutes at 230 ° C. in Labostomill to obtain graft polymerization.
Min, MAH modified polypropylene with a MAH graft ratio of 0.4% by weight.

Examples 1 to 9 and Comparative Examples 1 to 7 and modified polypropylene (modified PP-
1, modified PP-2, modified PP-3, modified PP-4) were mixed in a Henschel mixer at the ratios shown in Tables 1 and 2, and then 230 mm by using a 44 mmφ twin-screw extruder.
Kneading was performed at 250 rpm for 250 ° C., and carbon fibers (CF) were supplied from the middle of the extruder using a gravimetric feeder at a ratio shown in Tables 1 and 2 to obtain a carbon fiber reinforced polypropylene composition. .

Example 10 Polypropylene (manufactured by Tonen Kagaku KK; J209),
Using a twin-screw extruder, AXE and POX were mixed at a ratio shown in Table 1 at 230 ° C. and 250 rpm to perform kneading.
Carbon fiber (CF) was supplied from a weight type feeder installed in the middle of the extruder at a ratio shown in the table to obtain a carbon fiber reinforced polypropylene composition.

Comparative Example 8 Polypropylene (manufactured by Tonen Kagaku KK; J209)
A carbon fiber reinforced polypropylene composition was obtained in the same manner as in Example 10 with MAH and POX in the ratios shown in Table 2.

The carbon fiber reinforced polypropylene compositions obtained in Examples 1 to 10 and Comparative Examples 1 to 8 were measured for melt flow rate, tensile breaking strength, flexural modulus, Izod impact strength and heat distortion temperature. The results are shown in Tables and Table 2.

[0039]

[Table 1]

[0040]

[Table 2]

[0041]

[Table 3]

The methods for measuring the physical properties shown in Table 1 are as follows. (1) Melt flow rate: ASTM D-1238 (230 ℃,
2.16kg load) measured. (2) Tensile breaking strength: measured by ASTM D-638 (23 ° C). (3) Flexural modulus: measured by ASTM D-790 (23 ° C). (4) Izod impact strength: Measured by ASTM D-256 (23 ° C, with V notch). (5) Heat distortion temperature (HDT): ASTM D-648 (23 ℃, 1
8.6kg / cm ² load)

As is clear from Tables 1 and 2,
The carbon fiber reinforced polypropylene compositions of Examples 1-9 are
Compared with unmodified polypropylene containing no modified polypropylene (Comparative Example 1) and compositions containing unmodified polypropylene and carbon fibers (Comparative Examples 2 to 5), the breaking strength, flexural modulus, and Izod impact strength are excellent, and thermal deformation The temperature is also high.
Further, in comparison with Comparative Examples 6 to 7 containing the modified polypropylene with maleic anhydride, the Izod impact strength is particularly high and other physical properties are also excellent. Further, it is understood that the physical properties of the carbon fiber-reinforced polypropylene composition of Example 10 prepared by mixing the modified polypropylene at the time of kneading the carbon fibers are at the same level as those of the examples using the previously modified polypropylene.

[0044]

As described above, the composition of the present invention comprising the modified polypropylene resin containing the modified polypropylene and the carbon fiber is excellent in mechanical properties such as rigidity and impact resistance and heat resistance. Also, no strange odor is generated during molding. Such a composition of the present invention is suitable as various industrial materials such as automobile interior and exterior parts, home electric appliance parts, and electric component parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tatsuo Teraya 1-3-3 Nishitsurugaoka, Oi-cho, Iruma-gun, Saitama Tonen Corporation Research Institute (72) Inventor Yuji Fujita Nishitsuru, Oi-cho, Iruma-gun, Saitama Prefecture 1-3-1, Kugaoka Inside Tonen Corporation Research Institute

Claims (1)

[Claims] 1. (a) The following general formula (I): (In the formula, R represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, Ar represents an aromatic hydrocarbon group having 6 to 20 carbon atoms having at least one glycidyloxy group, and n
Is an integer of 1 to 4. 2% by weight of a modified polypropylene obtained by graft-polymerizing 0.1 to 15 parts by weight of an unsaturated glycidyl compound represented by
A fiber-reinforced polypropylene composition comprising (b) 5 to 70 parts by weight of carbon fiber based on 100 parts by weight of the polypropylene-based resin contained above.