WO2005073291A1

WO2005073291A1 - Carbon fiber-reinforced polyolefin resin composition and formed article made therefrom

Info

Publication number: WO2005073291A1
Application number: PCT/JP2005/001322
Authority: WO
Inventors: Koki Yano; Rikuo Onishi
Original assignee: Idemitsu Kosan Co., Ltd.
Priority date: 2004-02-02
Filing date: 2005-01-31
Publication date: 2005-08-11
Also published as: JP2005213479A; JP4586372B2

Abstract

Disclosed is a fiber-reinforced resin composition which is characterized by containing a carbon fiber (A), a polyolefin resin (B), and a modified polyolefin resin (C) having one or more kinds of functional groups reactive with a reactive functional group of the carbon fiber (A) at the following ratio (mass%). (A):[(B) + (C)] = 1-80:99-20

Description

Specification

TECHNICAL FIELD The present invention relates to a polyolefin-based carbon fiber reinforced resin composition and a molded article therefor.

The present invention relates to a polyolefin-based carbon fiber reinforced resin composition having improved properties such as flexural strength, flexural modulus, impact strength, and the like, and a molded article comprising the same.

Background art

[0002] In recent years, carbon fiber resin compositions have been evaluated as mechanical properties such as strength, rigidity, low specific gravity, and abrasion resistance, and have been attracting attention as industrially important materials. In particular, in the field of automobile parts and electronic material products, the usefulness of molded products of highly rigid resin compositions as substitutes for metal materials and glass fiber reinforced resin compositions is being studied.

[0003] Patent Documents 1 and 2 disclose a carbon fiber-reinforced resin composition using a polyolefin-based resin containing a specific rubber-based polymer, but this composition has poor impact strength. Was enough.

[0004] In general, to increase the strength of a glass fiber-reinforced resin composition, glass fibers (hereinafter sometimes referred to as GF) have a silanol group on the surface thereof. This is achieved by improving the interfacial strength between the matrix resin and the reinforcing fibers by adding a carboxylic acid or other modified polypropylene to the matrix resin. However, unlike carbon fiber (CF), which has a silanol group on the surface, the same method cannot be applied to carbon fiber.

[0005] Generally, in order to facilitate the handling of carbon fibers during impregnation and opening of carbon fibers and to improve the wettability with matrix resin, various sizing agents (for example, see Patent 3). Patent Document 4 discloses a carbon fiber resin composition obtained by treating a carbon fiber treated with a sizing agent with a maleic anhydride-modified polypropylene, whereby the impregnating property is improved and the strength is insufficient. .

[0006] Patent Document 1: JP-A-2002-3691 (Example 11)

Patent Document 2: Japanese Patent Application Laid-Open No. 2001-294760 (Example 13)

Patent Document 3: JP-A-2002-13069 Patent Document 4: JP 2003-277525

[0007] In view of the above situation, an object of the present invention is to improve the strength (flexural strength, flexural modulus, impact strength) of a polyolefin-based carbon fiber reinforced resin composition.

Disclosure of the invention

[0008] In order to achieve the above object, the present inventors have conducted intensive studies and have found that a modified polyolefin resin having a functional group (such as an amino group) capable of reacting with a reactive functional group possessed by carbon fiber is a carbon fiber. Reacts with the functional groups (carboxyl group, quinone group, etc.) present on the surface of the resin to form a bond, strengthens the interfacial strength between the matrix resin, polyolefin resin, and carbon fibers, and achieves the desired physical properties. Have been found, and the present invention has been completed.

That is, the present invention provides

(1) (A) carbon fiber,

(B) polyolefin-based resin, and

(C) (A) a modified polyolefin resin having at least one functional group capable of reacting with the reactive functional group of the carbon fiber,

Is contained in the following ratio (mass%).

(A): [(B) + (C)] = 1-80: 99--20;

(2) The fiber-reinforced resin composition according to the above (1), wherein the (B) polyolefin resin is polypropylene.

(3) The fiber-reinforced resin composition according to the above (1) or (2), wherein the functional group of the modified polyolefin resin (C) is an amino group or an epoxy group;

(4) A molded article obtained by molding the fiber-reinforced resin composition according to any one of the above (1) to (3).

According to the present invention, it is possible to provide a polyolefin-based carbon fiber reinforced resin composition having improved flexural strength, flexural modulus and impact strength.

[0014] The molded article of the present invention, which also has a polyolefin-based carbon fiber-reinforced resin composition, can be suitably used for automobile parts, motorcycles, bicycle parts and the like, particularly parts requiring rigidity and durability. .

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.

The fiber-reinforced resin composition of the present invention (hereinafter, referred to as the composition of the present invention)

(A) carbon fiber,

(B) polyolefin-based resin, and

In the following proportions (% by mass).

(A): [(B) + (C)] = 1-80: 99-1 20

First, essential components of the composition of the present invention will be described.

(A) Carbon fiber

(A) As the carbon fiber, various conventionally known carbon fibers can be used. Specific examples thereof include carbon fibers of polyacryl-tolyl type, rayon type, pitch type, polybutyl alcohol type, regenerated cell source, mesophase pitch force produced pitch type and the like.

[0017] The fiber diameter of the carbon fiber is preferably 3 to 30 µm, and more preferably 4 to 10 µm. If the fiber diameter is too small, the fiber is liable to break, and the productivity of the reinforcing fiber bundle may be reduced. In addition, when continuously producing pellets, a large number of fibers must be bundled, and complicated labor for connecting fiber bundles is required, which is not preferable because productivity is reduced. In addition, when the pellet length is fixed, if the fiber diameter is excessively large, the astrat ratio of the fiber decreases, and the reinforcing effect may not be sufficiently exhibited, which is not preferable. The aspect ratio is preferably from 5 to 6000. If the aspect ratio is too small, the strength is reduced, and if it is too large, the moldability may be reduced. (A) The aspect ratio of the carbon fiber can be determined from the average fiber diameter and the average fiber length by (average fiber length) / (average fiber diameter).

[0018] A continuous fiber bundle is used as a raw material for long carbon fibers, and this is commercially available as tow. Usually, the average fiber diameter is 3-30 m and the number of filament bundles is 500-24,000. Preferably, the average fiber diameter is 410 m and the number of bundles is 6,000 to 15,000.

[0019] Alternatively, chopped strands can be used as (A) carbon fibers. The length of the chopped strand is usually 1 to 20 mm, and the fiber diameter is about 3 to 30 m, preferably 4 to 10 m. μm.

[0020] The fiber length of the carbon fiber (A) constituting the composition of the present invention is usually 0.05 to 200 mm, preferably 0.2 to 50 mm, and more preferably 412 to 20 mm.

[0021] The average aspect ratio (fiber length Z fiber diameter) is usually 5 to 6000, preferably 30 to 3000, and more preferably <100 to 2000.

[0022] (A) The carbon fibers are preferably arranged in parallel with each other at substantially the same length, particularly at a length of 2 to 200 mm, preferably 412 to 20 mm.

(A) The surface of the carbon fiber is preferably subjected to surface treatment such as etching or coating. Oxidation etching treatment includes air oxidation treatment, oxygen treatment, treatment with oxidizing gas, treatment with ozone, corona treatment, flame treatment, (atmospheric pressure) plasma treatment, and oxidizing liquid (nitric acid, alkali metal hypochlorite). Aqueous solution, potassium dichromate sulfuric acid, potassium permanganate sulfuric acid) and the like. Examples of the substance that coats the carbon fiber include carbon, silicon carbide, silicon dioxide, silicon, plasma monomers, Feguchisen, and Sanshioridani.

[0024] If necessary, a sizing agent of urethane type, olefin type, acrylic type, nylon type, butadiene type or epoxy type may be used.

[0025] (B) Polyolefin resin

Examples of the (B) polyolefin resin include polypropylene, low-density polyethylene, ethylene α-olefin (for example, 1-butene, 1-hexene, 1-otene, 1-decene, etc.), and high-density polyethylene. And polypropylene is preferred.

[0026] (ii) Polypropylene resin as the polypropylene resin, propylene homopolymer, propylene random copolymer, propylene block copolymer, etc. Any force may be used. It is a propylene homopolymer.

[0027] The melt flow rate (hereinafter, referred to as MFR) of the polypropylene resin is usually from 1 to 300 gZl0 min, preferably from 10 to 250 gZlO min, more preferably from 20 to 200 gZlO min. If the MFR is less than lgZlO, the dispersibility of the reinforcing fibers in the molded article is reduced, and the appearance of the molded article may be poor.If the MFR is greater than 300 gZlO, the impact strength is reduced, which is not preferable. .

[0028] The MFR of the above polypropylene resin is based on JIS K 7210-1999, and the temperature is 230 ° C. , Load 2.16 kg.

[0029] The polypropylene resin that can be used in the present invention can be produced by the methods described in JP-A-5-32723, JP-A-11-71431, JP-A-2002-249624 and the like.

[0030] That is, polypropylene resin can be produced by slurry polymerization, gas phase polymerization, or liquid phase bulk polymerization of propylene or the like using a polymerization catalyst. As a polymerization method for producing such a propylene polymer, Any of batch polymerization and continuous polymerization can be used.

[0031] The molecular weight of the polypropylene resin during polymerization can be adjusted by the amount of hydrogen and the like as described in JP-A-2002-226510.

(C) Modified polyolefin resin having at least one functional group capable of reacting with the reactive functional group of the carbon fiber (A) (hereinafter referred to as (C) modified polyolefin resin! / )

In the present invention, the modified polyolefin resin (C) is a polyolefin resin in which an amino group, an alkylamino group, an arylamino group, a glycidyl group, an isocyanate group, a dihydroxazolyl group, or an epoxy group is introduced. Preferably, amino groups are introduced into the polyolefin resin. Examples of the polyolefin resin to be modified include polyethylene resin and polypropylene resin.

[0033] In the modified polyolefin resin (C), one or more functional groups may be introduced into the acid-modified polyolefin resin. The acid-modified polyolefin resin can be modified with an unsaturated carboxylic acid or a derivative thereof, and the polyolefin resin has a carboxyl group or a carboxylic anhydride group.

Unsaturated carboxylic acids used to modify polyolefin resins include, for example, acrylic acid, methacrylic acid, maleic acid, nadic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, sorbic acid, mesaconic acid, angelica Acids and the like. Derivatives of the unsaturated carboxylic acids include acid anhydrides, esters, amides, imides, metal salts and the like. For example, maleic anhydride, itaconic anhydride, citraconic anhydride, nadic anhydride, acrylic acid, etc. Methyl acrylate, methyl methacrylate, ethyl acrylate, butyl acrylate, monoethyl maleate, acrylamide, monoamide maleate, maleimide, N-butyl maleimi , Sodium acrylate, sodium methacrylate and the like. Among these, maleic anhydride or phthalic anhydride is particularly preferred, since unsaturated dicarboxylic acids and derivatives thereof are preferred.

[0034] (C) The modified polyolefin-based resin having the above-mentioned functional group allows (A) to react with a carboxyl group, a quinone group, or the like present on the surface of the carbon fiber; A bond between carbon fiber and polyolefin-based resin (matrix resin) can be formed.

When a polypropylene resin or a mixture thereof is used as (B) the polyolefin resin, it is preferable to use a modified polypropylene resin as the modified polyolefin resin (C).

[0036] The modified polypropylene resin includes a modified propylene homopolymer, a propylene random copolymer, a propylene block copolymer, and the like, similarly to the above-mentioned polypropylene resin.

For the modification of the polyolefin resin, methods such as graft modification, copolymerization, and terminal modification can be used.

[0038] Examples of the (C) modified polyolefin resin used in the present invention include an epoxy-modified polypropylene resin described in JP-A-9-263687 and a terminal amino acid described in JP-A-6-128322. Modified polypropylene resins, epoxy-terminated polypropylene resins disclosed in JP-A-8-253629, and amino-modified polypropylene resins obtained by reacting an acid-modified polyolefin resin with diamine are exemplified.

[0039] The crystallization temperature (Tc) of the modified polypropylene resin (C) is usually 90 to 125 ° C, preferably 1 to 125 ° C.

10-120 ° C. The limiting viscosity is usually 0.1 to 2.4 dlZg, preferably 0.2 to 1.6 dl / g.

The average number of functional groups per molecule of the modified polyolefin resin is usually 1.5 to 50 Z molecules, preferably 3 to 30 Z molecules, particularly preferably 5 to 20 Z molecules. When the average number of functional groups per molecule is 1.5 or more Z molecules or more, a network structure is formed and strength is easily obtained.

(C) The crystallization temperature (Tc) of the modified polyolefin resin can be measured with a differential scanning calorimeter (DSC). [0042] The intrinsic viscosity of (C) the modified polyolefin resin can be measured in tetralin at 135 ° C.

(C) The average number of functional groups per molecule of the modified polyolefin resin is calculated from the amount of functional groups added by Fourier transform infrared spectroscopy (FTIR) and the number average molecular weight measured by GPC. Can be.

Next, in the composition of the present invention, the mixing ratio of the components (A) to (C) is

(A): [(B) + (C)] = 1-80: 99-1 20

And preferably

(A): [(B) + (C)] = 2—40: 98—60

It is.

[0045] (A) If the proportion of the carbon fiber is less than 1% by mass, the effect of reinforcing the resin by the carbon fiber does not appear, and if it exceeds 80% by mass, the toughness may be lost.

[0046] The composition of the present invention may further contain various additives depending on the application, for example, dispersants, lubricants, plasticizers, flame retardants, antioxidants (phenol-based antioxidants, anti-phosphorylation agents). , Antioxidants, light stabilizers, UV absorbers, crystallization accelerators (nucleating agents), foaming agents, crosslinking agents, modifying additives such as antibacterial agents, pigments, dyes Coloring agents such as carbon black, titanium oxide, red iron oxide, azo pigments, anthraquinone pigments, phthalocyanine, talc, calcium carbonate, myritsu, clay, and other particulate fillers, and wollastonite and other short fiber fillers And whiskers such as potassium titanate.

[0047] These additives may be added at the time of producing a molded body from pellets, the force to be added to the pellets during the production of pellets.

[0048] specific gravity of the compositions of the present invention is usually at LOOOkgZm ³ or less, preferably, a 1000- 9 50kgZm ^3.

Next, a method for producing the composition of the present invention will be described.

When the composition of the present invention is a short fiber reinforced resin pellet, it can be manufactured by melt-kneading a part or all of the component (A) -one (C) in an extruder or the like, and can be produced by a long fiber reinforced resin. When it is a resin pellet, it can be manufactured by a known method such as a drawing method. The above (A)-(C) components may be separately melt-kneaded and then mixed (blended) !. [0050] In the long fiber reinforced resin pellets, the aspect ratio of the fibers in the composition becomes large, and a composition having high strength is easily obtained, so that a more remarkable effect is obtained.

[0051] The shape of the fiber-reinforced resin pellets may be any of powder, flake, and pellet.

[0052] The pellet length of the long fiber reinforced resin pellet is usually 2 to 200 mm. If the pellet length is too short, the effect of improving rigidity, heat resistance and impact strength is low, and warpage may increase, and if the pellet length is too long, molding may be difficult. The pellet length is preferably 3-1 OO mm, more preferably 4-1 20 mm, and particularly preferably 6 to 12 mm.

[0053] (A) The carbon fibers in the pellet are preferably arranged in a state substantially parallel to each other.

[0054] The long fiber reinforced resin pellets are obtained by introducing a roving of thousands of reinforcing fibers into an impregnating die and uniformly impregnating the molten thermoplastic resin between the filaments. It can be easily obtained by cutting to 200 mm).

For example, while the molten resin (components (B) and (C) above) is supplied from an extruder into an impregnation die provided at the extruder tip, the continuous fiber bundle is passed through the impregnating die. The resin is impregnated with molten resin, pulled out through a nozzle, and pelletized to a length of 2 to 200 mm.

[0056] As a method for impregnating the molten resin into the carbon fiber (A), there is no particular limitation, in which a roving is passed through a fluidized bed of a resin powder and then heated to a temperature equal to or higher than the melting point of the resin. 52-3985), a method of impregnating a roving of reinforcing fibers with a molten thermoplastic resin using a crosshead die (JP-A-62-60625, JP-A-63-132036, JP-A-63-264326, JP-A-1-208118), a method of blending a resin fiber and a mouthpiece of a reinforcing fiber and then heating the resin to a temperature higher than the melting point of the resin to impregnate the resin ( JP-A-61-118235), a method in which a plurality of rods are arranged inside a die, a roving is wound around the die in a zigzag shape, the fiber is opened, and a molten resin is impregnated (JP-A-10-264152). ), A method of passing between the spread pins without contacting the pins (published in WO97Z19805), twisting with a roller Can also be used provided such method for impregnating (JP-A-5 169 445), what Re ways.

[0057] In the process of melting the resin, an extruder having two or more feed sections is used, and A resin and a resin decomposing agent (for example, in the case of polypropylene resin, an organic peroxide is preferable) may be added from the eaves, and another resin may be added from the side feed.

[0058] Further, two or more extruders (extruding parts) are used, and one or more of the extruders are provided with a resin and a resin decomposer (for example, in the case of polypropylene resin, an organic peroxide). Thing is preferable)

[0059] The short fiber reinforced resin pellets can be produced by kneading and dispersing each component at a predetermined ratio using a roll mill, a Banbury mixer, a kneader, or the like. Dry blending may be performed using a tumbler set blender, Henschel mixer, ribbon mixer, or the like. The mixture is kneaded with a single-screw extruder, a twin-screw extruder or the like to obtain a pellet-shaped molding material. Carbon fiber can be fed from the top or side of the extruder from the gap!

Next, the molded article of the present invention will be described.

The molded article of the present invention is obtained by molding the above fiber-reinforced resin composition of the present invention.

[0061] The method for molding the molded article of the present invention includes known methods such as injection molding, extrusion molding, hollow molding, compression molding, injection compression molding, gas injection injection molding, and foam injection molding. The molding method can be applied without any restrictions. In particular, injection molding, compression molding and injection compression molding are preferred.

[0062] The molded article may be molded as it is of the composition of the present invention, or may be molded after being blended with a diluent. The blending of the fiber-reinforced resin pellets, which is the composition of the present invention, and a diluent composed of the same thermoplastic resin as the fiber-reinforced resin pellets, such as polyolefin resin, can be performed by a dry blending method. . Rather, in order to maintain the fiber length in the composition and obtain higher rigidity, impact resistance, and durability improvement effects, the molding machine such as an injection molding machine or the like should be used directly after the dry blending without passing through an extruder. It is preferred to provide The mixing ratio of the diluent is determined from the viewpoint of the effect of improving the rigidity, impact resistance and durability determined by the reinforcing fiber content of the fiber-reinforced resin pellets and the reinforcing fiber content required for the final molded product. Usually, it is 0 to 90% by mass.

[0063] The weight average fiber length of the (A) carbon fiber remaining after molding is usually 0.05 mm or more, preferably 1 mm or more. (A) If the weight average fiber length of carbon fiber is too short, rigidity and impact resistance The effect of improving properties and durability cannot be obtained.

[Example]

Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples.

The materials used in the examples and comparative examples are as follows.

[0065] (A) Carbon fiber:

Carbon fiber (chopped strand) HTA-C6-UEL1 (PAN-based, urethane-based sizing agent (2.5% added), fiber diameter 7 μm, fiber length (strand length) 6 mm; Toho Tenatas Co., Ltd. Made)

(B) Polyolefin-based resin:

Polypropylene resin, J-3000GP (Propylene homopolymer, MFR = 30gZlOmin .; Idemitsu Oil Co., Ltd.)

(C) Modified polyolefin resin:

Maleic acid-modified polypropylene, Polybond 3200 (acid addition amount zero. 5 mass ^_0/0, MFR =

250g / 10min.; Shiraishi Calcium Co., Ltd.)

[0068] Amino group-containing polypropylene resin (amino group-containing PP): Using the raw materials shown in Table 1 below

Amino group-containing PPs (1) and (2) produced under mixing conditions and kneading conditions were used.

[0069] The production of amino group-containing PP is performed by using a 35 mm twin-screw extruder (manufactured by Labotex) with a vacuum vent, performing vacuum venting, and blending the entire amount of raw materials from the top feed. Was. In addition, ilganox 1010 (manufactured by Chivas Specialty Chemicals Co .; antioxidant) and ilgafos 168 (manufactured by Chinoku Suphariti Chemicals Co .; antioxidant) were added as additive carohydrates per 6 kg of polypropylene (PP). , 3.6 g and 8.4 g respectively (200 total

Oppm).

[0070] Whether an amino group-containing PP is produced, by measuring the infrared absorption spectra before and after manufacture, 1670- 1810cm- peak considered to be due to maleic acid 'maleic anhydride ¹ disappeared, new 1500 — It was confirmed by the appearance of an absorption band presumed to be due to the amino group at 1700 cm " ¹ .

[Table 1] $; ¾ (sm¾¾¾ ^ s; 9 τ¾ ^ い TEM201: ¾π2 / 7 ~ ,.

() S, ¾ room, 007O21l 212

Polybond 3200: Maleic acid-modified polypropylene (above) HMD A: Hexamethylene diamine (Tokyo Kasei Co., Ltd.)

DADD: 1, 12—diaminododecane

Polypropylene resin, modified polypropylene resin and carbon fiber were added at the mixing ratio. After kneading the cylinder at 200 ° C and screw rotation at 350 rpm, cool the strand with water

And cut with a pelletizer to obtain carbon fiber reinforced resin pellets.

Examples 3 and 4 and Comparative Examples 3 and 4

Carbon fiber reinforced resin pellets were obtained in the same manner as in Example 2 and Comparative Examples 1 and 2, except that carbon fiber was charged from the side feed and the proportions of each component were changed as shown in Table 2 below. Was.

[Table 2]

Mixing ratio (% by mass)

Constituents Compound name (trade name)

Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4

(A) Carbon fiber HTA-C 6-UE L 1 10 10 ― ― 10 10 ― ―

(B) ° Reolefin resin J-3000GP 86 86 88 88 90 86 90 88 Feed * ° Lind 3200 (containing maleic acid group) ― ― ― ― ― 4 ― 2

(C) Modification containing functional group

This ^β Riorefuin resin amino group-containing PP (1) (amino group-containing) 4 - 2 - - - - - Amino group-containing PP (2) (amino group-containing) - 4 - 2 - - - - Sa boku 'Fi - (Α) Carbon fiber HTA-C 6-UE L 1 ― ― 10 10 ― ― 10 10

[0075] From the obtained carbon fiber reinforced resin pellets, an injection molded sample (multipurpose test piece A type) was produced in accordance with JIS K 7152-1-1999.

Using the sample, physical property items shown in Table 3 below were measured and evaluated. Show evaluation results

See Figure 3.

[0077] The weight average fiber length in the composition was calculated by the following formula, after extracting fibers with para-xylene, measuring the fiber length of 500 to 2000 fibers with an image processing device (manufactured by Lusettas). did.

Weight average fiber length = ∑ (fiber length) V ∑ fiber length

The outside ratio of fiber was calculated from the above weight average fiber length and fiber diameter.

[0078] [Table 3]

Physical properties Measurement method Unit Example 1 Example 2 Example 3 Example 4 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Density JIS 7112: 1999 kg / m ³ 950 950 950 950 950 950 950 950 950 Tensile fracture stress (23TC ) JIS K 7161: 1994 MPa 58 55 85 70 34 41 38 44 Flexural strength (23C) JIS K 7171: 1994 MPa 91 89 122 98 50 66 63 70 Flexural modulus (at 23) JIS K 7171: 1994 MPa 4810 4800 6850 6780 4120 4350 6220 6690 Charvi-impact strength (23, with notch) JIS K 7111: 1996 KJ / m ² 3.5 3.4 5.5 5.5 2.1 2.1 4.9 4.9 Weight average fiber length in composition ― ■ 0.15 0.15 0.3 0.3 0.15 0.15 0.3 0.3 Fiber outer ratio Fiber length / fiber diameter ― 21 21 43 43 21 21 43 43

[0079] From the results in Table 3, the carbon fiber reinforced resins of Examples 1 and 2 and Comparative Examples 1 and 2 and Examples 3 and 4 and Comparative Examples 3 and 4 respectively have densities and weight averages in the compositions. In spite of the fact that the fiber length and the fiber aspect ratio were the same, in Example 14 in which the amino group-containing polyolefin was added, the tensile fracture stress, flexural strength, flexural modulus and Charpy impact strength were It can be seen that each of them was improved as compared with those of Comparative Examples 1-4.

[0080] In the compositions of Comparative Examples 2 and 4 using the maleic acid-modified polyolefin, the functional group of the carbon fiber did not react with the maleic acid group, and a bond with the carbon fiber could be formed. It can be seen that the strength was not improved due to the absence of the above.

Industrial applicability

According to the present invention, it is possible to provide a carbon fiber reinforced resin composition having improved bending strength, bending elastic modulus, and impact strength.

[0082] Molded articles obtained from the fiber-reinforced resin composition of the present invention can be used for automobile parts (front end, fan shroud, cooling fan, engine under cover, engine cover, radiator box, side door, back door inner, Back door outer, skin, roof rail, door handle, luggage box, wheel cover, handle, cooling module, air cleaner), motorcycle. Bicycle parts (luggage box, handle, wheel)

, Housing-related parts (hot water cleaning valve seat parts, bathroom parts, chair legs, valves, meter bolts), other parts (power tool parts, mower handles, hose joints, resin bolts, concrete formwork), and especially It can be suitably used as automobile parts (including front end modules (including fan shroud 'fan' cooling modules), air cleaners and door parts) and valves that require rigidity and durability.

Claims

The scope of the claims

[1] (A) carbon fiber,

(B) polyolefin-based resin, and

(C) the modified polyolefin resin having at least one functional group capable of reacting with the reactive functional group of the carbon fiber (A);

Is contained in the following ratio (mass%).

(A): [(B) + (C)] = 1-80: 99-1 20

[2] The fiber-reinforced resin composition according to claim 1, wherein the (B) polyolefin resin is a polypropylene resin.

[3] The fiber-reinforced resin composition according to claim 1, wherein the functional group of the modified polyolefin resin (C) is an amino group or an epoxy group.

[4] A molded article obtained by molding the fiber-reinforced resin composition according to claim 1.