JP2006056938A - Polyamide resin composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyamide resin composition which comprises a polyamide resin, a fibrous reinforcing material, and an inorganic filler, and has excellent flowability and rigidity. <P>SOLUTION: This polyamide resin composition comprising a polyamide resin (a), a fibrous reinforcing material (b), and an inorganic filler (c) excluding (a) in amounts of 35 to 60 wt. %, 35 to 60 wt. %, and 1 to 20 wt. %, respectively, per 100 wt. % of the polyamide resin composition, is characterized in that the relative viscosity of the polyamide resin (a) is ≤2.3 measured at 25°C in a 98 % concentrated sulfuric acid solution having a sample concentration of 0.01 g/ml. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention comprises a polyamide resin, a fibrous reinforcing material, and an inorganic filler, has both fluidity and rigidity, which are contradictory properties, and can be suitably used for molding applications, particularly for overmolding hollow bodies. The present invention relates to a resin composition.

  In recent years, there has been a great demand for weight reduction of automobile bodies due to increasing environmental awareness in the automobile field, and expectations for resins are increasing. In the electrical and electronic field, lightness, thinness, and miniaturization are increasing. For these reasons, it is desired to reduce the weight and the rigidity of the material.

  It is important to reduce the thickness for the above demand for weight reduction. In order to reduce the thickness, the rigidity required to form a part even if it is thin and the fluidity capable of filling the thin portion during molding are required.

  Furthermore, modularization of parts is being promoted in the automobile field, and there is a demand for a high-rigidity material because it should not be deformed even when many parts are assembled.

  In order to improve the rigidity, a method of adding a fibrous reinforcing material or an inorganic filler is generally used, but there is a problem that the fluidity is lowered. Thus, since rigidity and fluidity are contradictory properties, it has been extremely difficult to achieve both.

  In order to solve such a problem, a technique for improving fluidity by adjusting the average particle size and particle size distribution of the inorganic filler has been disclosed (for example, Patent Document 1). However, this known example defines the particle size distribution of the same type of filler, and does not improve the combination of different types / different shapes of reinforcing materials and inorganic fillers. Furthermore, there is no suggestion in this known example if nothing is described about improvement in rigidity.

  In addition, a well-known example has been filed in which a fibrous reinforcing material and an inorganic filler are used in combination, and the aspect ratio of the inorganic filler is specified to be a specific value or less, but this is a technique for improving weld characteristics and appearance. There is no description or suggestion regarding both the rigidity and the fluidity (for example, Patent Document 2).

  Another known example is a technique characterized by improving mechanical properties and suppressing deformation by using a filler with a large aspect ratio, which is completely different from the present application using a filler with a small aspect ratio. Yes (for example, Patent Documents 3 to 5).

  Furthermore, in the above known examples, there is no known example in which the polyamide resin is a copolymer composed of hexamethylene adipamide units, hexamethylene isophthalamide units and / or caproamide units.

On the other hand, techniques for overmolding a hollow body obtained by blow molding are described in Patent Documents 6 to 8, but these known examples relate to a technique relating to a method for overmolding a hollow body, and a molded product thereof. It does not relate to a resin material to be overmolded.
JP 2003-3074 A (paragraphs [0008] to [0016]) JP 2003-213011 A (paragraphs [0028] to [0029]) JP 2001-151900 A (paragraphs [0030] to [0034]) JP-A-6-279615 (paragraphs [0038] to [0040]) JP-A-6-145499 (paragraph [0011]) Japanese Patent Laid-Open No. 5-215025 (paragraph [0012]) JP-A-5-338015 (paragraphs [0004] to [0010]) JP-A-7-1000085 (paragraphs [0007] to [0011])

  An object of the present invention is to provide a polyamide resin composition comprising a polyamide resin, a fibrous reinforcing material, and an inorganic filler, and having fluidity and rigidity, which are contradictory properties.

The above issues are mainly
(1) Polyamide resin (a) 35 to 60% by weight, fibrous reinforcing material (b) 35 to 60% by weight, and inorganic fillers (c) 1 to other than (b) with respect to 100% by weight of the polyamide resin composition A polyamide resin composition comprising 20% by weight, wherein the relative viscosity measured at 25 ° C. in a 98% concentrated sulfuric acid solution of a polyamide resin (a) sample concentration of 0.01 g / ml is 2.3 or less. A polyamide resin composition,
(2) Part or all of the polyamide resin (a)
A copolymer comprising 65 to 95% by weight of hexamethylene adipamide unit (A1) and 35 to 5% by weight of hexamethyleneisophthalamide unit (A2), or 65 to 95% by weight of hexamethylene adipamide unit (A1) And a copolymer comprising a total of 35 to 5% by weight of hexamethyleneisophthalamide units (A2) and caproamide units (A3),
And the polyamide resin composition according to the above (1), which satisfies the following formula (1):

（３）無機充填材（ｃ）のアスペクト比が１０以下であることを特徴とする上記（１）または（２）記載のポリアミド樹脂組成物、
（４）繊維状強化材（ｂ）が炭素繊維であることを特徴とする上記（１）〜（３）いずれかに記載のポリアミド樹脂組成物、
（５）中空体のオーバーモールド用樹脂であることを特徴とする上記（１）〜（４）いずれかに記載のポリアミド樹脂組成物、
により達成される。

(3) The aspect ratio of the inorganic filler (c) is 10 or less, the polyamide resin composition according to the above (1) or (2),
(4) The polyamide resin composition according to any one of (1) to (3) above, wherein the fibrous reinforcing material (b) is a carbon fiber,
(5) The polyamide resin composition as described in any one of (1) to (4) above, which is a resin for overmolding of a hollow body,
Is achieved.

  A polyamide resin composition comprising a polyamide resin, a fibrous reinforcing material, and an inorganic filler and having both fluidity and rigidity can be provided.

  Embodiments of the present invention will be described below.

  The polyamide resin (a) used in the present invention is a polyamide mainly composed of amino acids, lactams or diamines and dicarboxylic acids. Representative examples of the main constituents include amino acids such as 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and paraaminomethylbenzoic acid, lactams such as ε-caprolactam and ω-laurolactam, and tetramethylenediamine. , Hexamethylenediamine, 2-methylpentamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, 2,2,4- / 2,4,4-trimethylhexamethylenediamine, 5-methylnonamethylenediamine, Metaxylylenediamine, paraxylylenediamine, 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, Bis (4-aminosi Chlohexyl) methane, bis (3-methyl-4-aminocyclohexyl) methane, 2,2-bis (4-aminocyclohexyl) propane, bis (aminopropyl) piperazine, aminoethylpiperazine, aliphatic, alicyclic, aromatic Diamines, and adipic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, terephthalic acid, isophthalic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodium sulfoisophthalic acid Examples include aliphatic, alicyclic, and aromatic dicarboxylic acids such as acids, 2,6-naphthalenedicarboxylic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid. In the present invention, nylon derived from these raw materials Homopolymers or copolymers, each alone or in the form of a mixture It can be used.

  Specific examples of particularly useful polyamide resins in the present invention include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyhexamethylene Bacamide (nylon 610), polyhexamethylene dodecane (nylon 612), polyundecanamide (nylon 11), polydodecanamide (nylon 12), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6/66) , Polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene iso Talamide / polycaproamide copolymer (nylon 66 / 6I / 6), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), polyhexamethylene terephthalamide / polydodecanamide copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), poly Xylylene adipamide (nylon XD6), polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), polyno Terephthalamide (nylon 9T), and mixtures thereof, or is a copolymer and the like.

  Among them, nylon 6, nylon 66, nylon 610, nylon 6/66 copolymer, nylon 66 / 6I copolymer, nylon 66 / 6I / 6 copolymer are preferable, and particularly nylon 66 / 6I copolymer, nylon 66 / 6I / 6 copolymer, and these These mixtures are preferred in terms of mechanical properties and fluidity.

In addition, in the nylon 66 / 6I copolymer and the nylon 66 / 6I / 6 copolymer, 65% to 95% by weight of the hexamethylene adipamide unit (A1) and 35% to 5% of the hexamethyleneisophthalamide unit (A2) are each 100% by weight. A copolymer comprising:
Or it is especially preferable that it is a copolymer consisting of 65 to 95% by weight of hexamethylene adipamide units (A1) and a total of 35 to 5% by weight of hexamethyleneisophthalamide units and caproamide units (A3).

  In addition, the value (formula (1)) obtained by dividing the weight fraction (wt%) of the caproamide unit by the weight fraction (wt%) of hexamethyleneisophthalamide is preferably 0 or more and 10 or less, and more preferably Is from 0.1 to 5, particularly preferably from 0.3 to 1. If this value exceeds 10, the moldability and appearance are insufficient. Although it is not always necessary to copolymerize the capramide unit as described above, it is preferable to use it in terms of excellent appearance.

また、これらポリアミド樹脂の重合度は、サンプル濃度０．０１ｇ／ｍｌの９８％濃硫酸溶液中、２５℃で測定した相対粘度としては、機械特性や流動性の点で２．３以下のものである。好ましくは１．８〜２．２の範囲のポリアミド樹脂である。

The degree of polymerization of these polyamide resins is 2.3 or less in terms of mechanical properties and fluidity as a relative viscosity measured at 25 ° C. in a 98% concentrated sulfuric acid solution having a sample concentration of 0.01 g / ml. is there. A polyamide resin in the range of 1.8 to 2.2 is preferred.

  The content of the polyamide resin (a) is 35 to 60% by weight with respect to the polyamide resin composition in terms of fluidity and mechanical properties.

  In addition, a copper compound is preferably used for the polyamide resin in order to improve long-term heat resistance. Specific examples of copper compounds include cuprous chloride, cupric chloride, cuprous bromide, cupric bromide, cuprous iodide, cupric iodide, cupric sulfate, nitric acid. Cupric, copper phosphate, cuprous acetate, cupric acetate, cupric salicylate, cupric stearate, cupric benzoate, inorganic copper halide and xylylenediamine, 2-mercaptobenzimidazole And copper compounds such as benzimidazole. Among these, monovalent copper halide compounds are preferable, and cuprous acetate, cuprous iodide and the like can be exemplified as particularly suitable copper compounds. The addition amount of the copper compound is usually preferably 0.01 to 2 parts by weight and more preferably 0.015 to 1 part by weight with respect to 100 parts by weight of the polyamide resin. If the amount added is too large, liberation of metallic copper occurs during melt molding, and the value of the product is reduced by coloring. In the present invention, an alkali halide can be added in combination with a copper compound. Examples of the alkali halide compound include lithium chloride, lithium bromide, lithium iodide, potassium chloride, potassium bromide, potassium iodide, sodium bromide and sodium iodide. Sodium chloride is particularly preferred.

  Moreover, you may add another polyamide resin in the range which does not impair the effect of this invention. Other polyamide resins include polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyhexamethylene sebacamide (nylon 610), polyhexa Methylenedodecanamide (nylon 612), polyundecanamide (nylon 11), polydodecanamide (nylon 12), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6/66), polycaproamide / polyhexamethylene terephthalate Amide copolymer (nylon 6 / 6T), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide / polycaproamide Rimmer (nylon 66 / 6I / 6), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), poly Hexamethylene terephthalamide / polydodecanamide copolymer (nylon 6T / 12), polyhexamethylene adipamide / polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6T / 6I), polyxylylene adipamide (Nylon XD6), polyhexamethylene terephthalamide / poly-2-methylpentamethylene terephthalamide copolymer (nylon 6T / M5T), polynonamethylene terephthalamide (nai Down 9T), and mixtures thereof, or is a copolymer and the like.

  The fibrous reinforcing material (b) used in the present invention is contained in the polyamide resin composition of the present invention in an amount of 35 to 60% by weight, preferably 40 to 55% by weight, in terms of fluidity and rigidity. % Content.

  The fibrous reinforcing material (b) used in the present invention is not particularly limited, but is glass fiber, PAN-based or pitch-based carbon fiber, stainless steel fiber, metal fiber such as aluminum fiber or brass fiber, aromatic Examples thereof include organic fibers such as polyamide fibers, gypsum fibers, ceramic fibers, asbestos fibers, zirconia fibers, alumina fibers, silica fibers, titanium oxide fibers, silicon carbide fibers, rock wool, potassium titanate whiskers, and silicon nitride whiskers. Of these, glass fibers, PAN-based and pitch-based carbon fibers are preferable, and PAN-based carbon fibers are particularly preferable in terms of rigidity, fluidity, and specific gravity.

  The inorganic filler (c) used in the present invention is different from the fibrous reinforcing material (b), and its addition amount is 1 to 20% by weight, and is a polyamide resin composition in terms of mechanical properties and fluidity. 3 to 15% by weight is more preferable.

  The total amount of the fibrous reinforcing material (b) and the inorganic filler (c) is preferably 40 to 65% by weight based on the polyamide resin composition in terms of fluidity and rigidity. In addition, the weight ratio (b / c) between the fibrous reinforcing material (b) and the inorganic filler (c) is preferably in the range of 1 to 20 in terms of both rigidity and fluidity.

  Furthermore, the aspect ratio of the inorganic filler (c) is preferably 10 or less, more preferably 3 or less, in terms of both fluidity and rigidity. Moreover, it is preferable from the point of fluidity | liquidity that the average particle diameter of an inorganic filler (c) is 1/2 or less of the diameter of a fibrous reinforcement (b).

  For example, with respect to a resin composition comprising a polyamide resin / fibrous reinforcing material, when a part of the polyamide resin is replaced with an inorganic filler within the above-described range of the inorganic filler, the fluidity is They found it to improve. That is, the present inventors have found that the fluidity is improved as a polyamide resin composition, even though the flowable polyamide resin is replaced with a solid inorganic filler. Furthermore, it discovered that a more favorable effect was acquired by making the addition amount ratio of an inorganic filler and a fibrous reinforcement, and the particle size of an inorganic filler into the above.

The shape of the inorganic filler (c) used in the present invention is not particularly limited, and an inorganic filler such as a plate shape, a needle shape, or a spherical shape can be used.
Here, the average particle diameter of the inorganic filler is a numerical value measured by a laser diffraction method. The aspect ratio is an average value of values obtained by dividing the longest length of 100 randomly extracted fillers by the shortest length. The longest length and the shortest length of the inorganic filler can be measured by observing the inorganic filler itself using a microscope such as SEM. As a measuring method, a method of measuring using an observation photograph of a microscope and a ruler, or a method of measuring using an observation image and a length measuring function can be adopted if the microscope has a length measuring function. The observation magnification can be appropriately selected depending on the particle size of the inorganic filler.

  Specifically, whisker-like filler, wollastonite, sericite, kaolin, mica, clay, bentonite, asbestos, talc, alumina silicate and other swellable layered silicates such as montmorillonite and synthetic mica, alumina, Metal compounds such as silicon oxide, magnesium oxide, zirconium oxide, titanium oxide and iron oxide, carbonates such as calcium carbonate, magnesium carbonate and dolomite, sulfates such as calcium sulfate and barium sulfate, glass beads, ceramic beads, boron nitride And non-fibrous fillers such as silicon carbide, calcium phosphate, silica, and graphite.

  Moreover, said filler can also be used in combination of 2 or more types. In addition, the surface of the filler used in the present invention is a known coupling agent (for example, silane coupling agent, titanate coupling agent, etc.), other surface treatment agents, and swellable layered silicates. It may be pretreated with an organic onium ion.

  In the polyamide resin composition of the present invention, in addition to (a) to (c), other components can be contained within a range not impairing the effects of the present invention. In this case, (a) to (c) It is necessary to make a polyamide resin composition with a total of 100% by weight and other components. Examples of other components include antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphites, and their substitutes), weathering agents (resorcinols, salicylates, benzotriazoles, benzophenones, Hindered amines, etc.), release agents and lubricants (montanic acid and its metal salts, its esters, their half esters, stearyl alcohol, stearamide, various bisamides, bisureas, polyethylene waxes, etc.), pigments (cadmium sulfide, phthalocyanine, carbon black Etc.), dyes (nigrosine, etc.), crystal nucleating agents (talc, silica, kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agents (alkyl sulfate type anions) Antistatic agent, poly Nonionic antistatic agents such as xylethylene sorbitan monostearate, betaine amphoteric antistatic agents, etc.), flame retardants (eg, red phosphorus, melamine cyanurate, magnesium hydroxide, hydroxides such as aluminum hydroxide, Ammonium polyphosphate, brominated polystyrene, brominated polyphenylene ether, brominated polycarbonate, brominated epoxy resins or combinations of these brominated flame retardants and antimony trioxide), other polymers, and the addition of these Can do.

  It does not specifically limit as a manufacturing method of the polyamide resin composition of this invention, A well-known method can be used. For example, a polyamide resin (a), a fibrous reinforcing material (b), and an inorganic filler (c) are collectively fed to an extruder and melt-kneaded, or a fibrous reinforcing material (b), an inorganic filler (c ) Can be used for side feed and melt kneading.

  As a method for overmolding a hollow body using the polyamide resin composition of the present invention, a method of injection molding or injection compression molding of the polyamide resin composition of the present invention after inserting the hollow body into a mold is adopted. can do.

  The method for forming the hollow body is not limited, and known methods such as blow molding, lost core method, vibration welding, ultrasonic welding, spin welding, laser welding, DSI molding, and DRI molding can be employed.

  The polyamide resin of the present invention can be used for molded articles in various fields such as the automobile field and the electric / electronic field, taking advantage of good flow and high rigidity. For example, in the automotive field, cylinder head cover, timing belt cover, intake manifold, balance shaft gear, oil brake valve, oil level gauge, oil cleaner case, radiator tank, water pump impeller, thermostat housing, cooling fan, intercooler tank, air duct , Air control valve, air regulator, air flow meter housing, air duct intake, silencer, resonator, exhaust gas pump side seal, exhaust gas valve, carburetor, gasoline injection nozzle, piston valve, carburetor valve, surge tank, fuel filter housing, fuel strainer, Fuel case, canister, EGI Tube, solenoid valve, gasoline float, gasoline chamber, fuel check valve, fuel injector, fuel injector connector, fuel injector nozzle cover, fuel filler cap, master cylinder piston, clutch oil reservoir, thrust washer, shift arm coating, shift lever knob, Transmission case, Turkish thrust washer, transmission bush, power steering tank, steering column cover, steering horn pad, steering ball joint, wheel full cap, wheel cap center, wheel center hub cap, brake oil reservoir, brake oil float, brake brake Bar cap, Side brake wire protector, Radiator grille, Front end bumper, Rear end bumper, Bumper molding, Front fender, Side mirror stay, Side mirror housing, Emblem, Retractable headlamp cover, Electric mirror base, Fuel lid, Bonnet hood looper, Extract Grill, door, side louver, door latch cover, door side molding, outer door handle, pillar louver, trunk lower back finisher, trunk clear apron, hatchback slide bracket, license plate, license plate pocket, fuel lid, sunroof frame, side molding, Window pivot, window glass slider, window Umor, air spoiler, instrument panel core, lid outer, center cluster, switch, upper garnish, lid cluster, meter hood, meter panel, glove box, change lever cover, glove box lid, glove box knob, glove door outer, Ash tray lamp housing, ash tray panel, sun visor bracket, sun visor shaft, sun visor holder, pillar garnish, rear mirror stay, regulator handle, door trim, inside door lock knob, inner lock knob, window regulator handle, window regulator handle knob, roof Side rail garnish, armrest insert, armless Base, armrest guide, rear shelf side, headrest guide, seat belt tongue plate, seat belt retractor gear, seat belt buckle, seat belt through anchor, lid cluster, safety belt mechanism parts, cooler sirocco fan, cooler vacuum pump, air conditioner magnet Clutch bobbin, air conditioner actuator, compressor valve, air ventilation fin, air conditioner adjustment knob, heater core tank, heater valve, generator coil bobbin, generator cover, generator bush, circuit board, brush holder, condenser case, regulator case, starter lever, starter Coil bobbin, starter interval gear, distributor -Point point bush, ignition coil case, ignition coil bobbin, distributor insulation terminal, distributor cap, sleeve bearing, helical gear, vacuum controller, junction box, wire harness connector, relay terminal base case, coil bobbin, fuse box, switch base, Relay case, various switch boards, lamp socket, lamp reflector, back horn housing, silent gear, power window switch board case, wiper lever, washer motor housing, wiper motor insulator, wiper arm head cover, washer nozzle, wiper arm head, speedometer Driven gear, speed Meter control, meter connector, rotation sensor, speed sensor, power seat gear housing, brush holder, commutator, motor gear, bonnet clip, molding clip, interior clip, bumper clip, band clip for electrical wiring, antenna inner tube, fender , Spoilers, roof rails, tailgates, bumpers, and base materials for module parts in which these parts are assembled. Among these, it can be suitably used for a part having a hollow portion.

  Other applications include mechanical parts such as housings for personal computers, liquid crystal projectors, mobile devices, mobile phones, internal combustion engines, power tool housings, various electrical and electronic parts, medical equipment, food containers, households. -Office supplies, building material related parts and furniture parts.

  Hereinafter, although an example is given and the present invention is explained in detail, the gist of the present invention is not limited only to the following examples.

[raw materials]
The raw materials used in Examples and Comparative Examples are as shown below. Unless otherwise specified, polymerization was carried out and adjusted according to conventional methods.

<Polyamide resin>
Polyamide resin 1: Polyamide 66 resin (relative viscosity 2.2)
Polyamide resin 2: Polyamide 66 resin (relative viscosity 2.5)
Polyamide resin 3: Polyamide 66 / Polyamide 6I = 80 wt% / 20 wt% copolymer (relative viscosity 2.0)
Polyamide resin 4: Polyamide 66 / Polyamide 6I / Polyamide 6 = 80 wt% / 15 wt% / 5 wt% copolymer (relative viscosity 2.1).

<Fibrous reinforcement>
Carbon fiber: TS12 (fiber diameter 7 μm, fiber length 6 mm chopped strand) (manufactured by Toray Industries, Inc.).

<Inorganic filler>
Calcium carbonate: Vigot HT (manufactured by Shiroishi Calcium Co., Ltd.) average particle size 0.2 μm, aspect ratio 1.1.
Particulate aluminum borate: Albolite FA03 (manufactured by Shikoku Kasei Co., Ltd.) Average particle size 3 μm, aspect ratio 1.2.
Talc: LMS100 (manufactured by Fuji Talc Kogyo Co., Ltd.) Average particle size 6 μm, aspect ratio 30.

[Measuring method]
(1) Bending properties Measured according to ASTM D790.

(2) Melt viscosity Using a Toyo Seiki Capillograph heated to 300 ° C., the pellet was put into the apparatus and allowed to stay for 5 minutes, and then the melt viscosity at a shear rate of 1000 sec ⁻¹ was measured.

(3) The inorganic filler itself is observed using an aspect ratio scanning electron microscope, and an average value of values obtained by dividing the longest length of 100 randomly selected inorganic fillers (c) by the shortest length is obtained. It was.
The longest length and the shortest length were measured using a microscopic observation photograph and a ruler. The calcium carbonate and talc were observed at a magnification of 10,000 times, and the particulate aluminum borate was observed at a magnification of 2000 times.

(4) Overmolding of hollow body A hollow body having an inner diameter of 10 cm and a wall thickness of about 1.7 mm was molded by blow molding using glass fiber 30% by weight reinforced nylon 66. The obtained hollow body was inserted into a mold, the thermoplastic resin composition of the present invention was injection-molded, and the deformation and collapse of the hollow body were observed.
○: No problem.
X: Deformation, crushing, resin leakage, etc.

Examples 1-6, Comparative Examples 1-4
The polyamide resin is supplied from the main feeder of the twin-screw extruder at the ratio shown in Table 1, and melted at a kneading temperature of 300 ° C. and a screw speed of 200 rpm by supplying a fibrous reinforcing material and an inorganic filler from the side feeder in the middle of the cylinder. Kneading was performed. After the obtained pellets were dried, injection molding of test pieces and overmolding of a hollow body were performed under conditions of a cylinder temperature of 300 ° C. and a mold temperature of 80 ° C. The evaluation results are shown in Table 1.

実施例１〜６および比較例１〜４の結果より、本発明の樹脂は良好な剛性と流動性を備えたものであった。

From the results of Examples 1 to 6 and Comparative Examples 1 to 4, the resin of the present invention had good rigidity and fluidity.

  A polyamide resin composition comprising a polyamide resin, a fibrous reinforcing material, and an inorganic filler and having fluidity and rigidity, which are contradictory properties, can be provided.

Claims (5)

Polyamide resin (a) 35-60% by weight with respect to 100% by weight of the polyamide resin composition,
Fibrous reinforcement (b) 35-60% by weight,
Inorganic fillers other than (b) (c) 1 to 20% by weight
A polyamide resin composition comprising:
A polyamide resin composition having a relative viscosity of 2.3 or less measured at 25 ° C. in a 98% concentrated sulfuric acid solution having a sample concentration of 0.01 g / ml of the polyamide resin (a). Part or all of the polyamide resin (a)
A copolymer comprising 65 to 95% by weight of hexamethylene adipamide unit (A1) and 35 to 5% by weight of hexamethylene isophthalamide unit (A2), or 65 to 95% by weight of hexamethylene adipamide unit (A1) And a copolymer comprising a total of 35 to 5% by weight of hexamethyleneisophthalamide units (A2) and caproamide units (A3),
And the following formula (1) is satisfied, The polyamide resin composition of Claim 1 characterized by the above-mentioned.

The aspect ratio of an inorganic filler (c) is 10 or less, The polyamide resin composition of Claim 1 or 2 characterized by the above-mentioned. The polyamide resin composition according to any one of claims 1 to 3, wherein the fibrous reinforcing material (b) is a carbon fiber. The polyamide resin composition according to any one of claims 1 to 4, wherein the polyamide resin composition is a hollow body overmold resin.