JP3528838B2 - Fuel component excellent in fuel resistance of welded portion and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel tank, a fuel hose, and a canister having excellent welded portion fuel resistance .
The present invention relates to a part attached to any of them (hereinafter referred to as a fuel part) and a manufacturing method thereof. More specifically, the present invention relates to a fuel component having excellent fuel permeation resistance and excellent fuel resistance of a welded portion over a long period of time, and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, for safety and environmental measures, it has been required to reduce the amount of fuel volatilized from the wall or connection of a fuel tank or accessory parts. For example, in the field of automobiles, a fuel tank body of an automobile is manufactured from metal or resin, and in the case of a resin fuel tank, a method of sulfonation of a resin to reduce a permeation amount of fuel from the tank body (SO ₃ treatment, Japanese Patent Publication No. 46-2391
No. 4), a fluorine treatment method (F ₂ treatment), a hollow molded product having a multilayer structure with a barrier resin (Japanese Patent Publication No. Sho 55-49989), and polyethylene in a continuous matrix phase of polyethylene. A method of dispersing the barrier resin in the form of flakes (Japanese Patent Publication No. 60-14695) has been developed.

However, even if the permeation amount of fuel from the fuel tank main body is reduced by the above method, the permeation amount from various parts (for example, valves) attached to the fuel tank is large and the fuel is This is an obstacle to reducing the amount of volatilization from all parts for use. This is because the various parts attached to the fuel tank are made of high-density polyethylene, which is the same material as the fuel tank, in order to obtain sufficient adhesive strength with the fuel tank. Because it is inferior.

Therefore, it has been studied to manufacture various parts attached to the fuel tank with polyamide resin or the like having excellent fuel permeability, but this time, a problem that sufficient adhesion strength with the fuel tank cannot be obtained. was there.

[0005]

SUMMARY OF THE INVENTION The object of the present invention is to solve the above-mentioned problems and to have excellent fuel permeation resistance and fuel resistance of the welded portion, particularly fuel resistance of the welded portion over a long period of time. A fuel component and a manufacturing method thereof are provided.

[0006]

Means for Solving the Problems As a result of intensive studies made by the present inventors in order to solve this problem, the concentration of amino end groups>
The inventors have found that the object can be achieved by using a crystalline polyamide resin having a carboxyl end group concentration, and arrived at the present invention.

That is, the present invention relates to a fuel component which is made of a crystalline polyamide resin having an amino terminal group concentration> a carboxyl terminal group concentration and is excellent in fuel resistance of a welded portion.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is described in detail below.
The crystalline polyamide resin of the present invention has a concentration of amino end groups higher than that of carboxyl end groups. Further, it is desirable that the amino terminal group concentration is 50 meq or more, preferably 60 meq or more per 1 kg of the polymer. When the amino terminal group concentration is excessive, when it is welded to a polyolefin resin modified with an unsaturated carboxylic acid or its derivative, the welding strength becomes excellent and excellent fuel resistance is exhibited.

As the crystalline polyamide resin of the present invention,
An aliphatic polyamide resin composed of an aliphatic diamine and an aliphatic dicarboxylic acid, or a lactam or an aminocarboxylic acid is preferable.

As the monomer component of the aliphatic polyamide resin, an aliphatic diamine having 4 to 12 carbon atoms and 6 to 1 carbon atoms are used.
Examples thereof include aliphatic dicarboxylic acids having 2 carbon atoms, lactams having 6 to 12 carbon atoms, and aminocarboxylic acids having 6 to 12 carbon atoms. Specific examples of the aliphatic diamine include tetramethylenediamine, hexamethylenediamine, octamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and the like, and specific examples of the aliphatic dicarboxylic acid include adipic acid. , Heptane dicarboxylic acid, octane dicarboxylic acid, nonane dicarboxylic acid, undecane dicarboxylic acid, dodecane dicarboxylic acid and the like, a preferred combination of aliphatic diamine and aliphatic dicarboxylic acid is an equimolar salt of hexamethylene diamine and adipic acid. . Specific examples of lactams include α
-Pyrrolidone, ε-caprolactam, ω-laurolactam, ε-enanthlactam and the like, and specific examples of the aminocarboxylic acid include 6-aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid and 12-amino. Examples thereof include dodecanoic acid, and 6-aminocaproic acid, 12-aminododecanoic acid, ε-caprolactam and laurolactam are preferable. The aliphatic polyamide-forming monomer can be used not only as a single component but also as a mixture of two or more components.

Specific examples of the aliphatic polyamide resin formed from these monomer components include nylon 6, nylon 66 and nylon 12, which may be homopolymers or copolymers of two or more kinds.

The crystalline polyamide resin of the present invention is preferably a crystalline semi-aromatic polyamide resin containing at least one aromatic monomer component. As the crystalline semi-aromatic polyamide resin containing one or more aromatic monomer components,
Examples thereof include a copolyamide resin containing at least one aromatic monomer component such as an aromatic dicarboxylic acid component such as terephthalic acid, isophthalic acid and naphthalene dicarboxylic acid.
It is preferably a crystalline semi-aromatic copolyamide resin having a melting point of 260 ° C. or higher and lower than 320 ° C., more preferably one or more aromatic monomer components, and more preferably one or more aromatic monomer components. Melting point is 290 ° C or higher and 316 ° C
Less than crystalline semi-aromatic copolyamide resin. Preferred combinations of crystalline semi-aromatic copolyamide resins containing one or more aromatic monomer components include equimolar salts of aliphatic diamine and aliphatic dicarboxylic acid, and equimolar salts of aliphatic diamine and aromatic dicarboxylic acid. And / or a crystalline copolyamide resin comprising an aliphatic polyamide-forming monomer.

Here, the aliphatic diamine has 4 to 12 carbon atoms.
Examples of the aliphatic diamine include tetramethylenediamine, hexamethylenediamine, octamethylenediamine, nonamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and the like. The aliphatic dicarboxylic acid is an aliphatic dicarboxylic acid having 6 to 12 carbon atoms, and examples thereof include adipic acid, heptanedicarboxylic acid, octanedicarboxylic acid, nonanedicarboxylic acid, undecanedicarboxylic acid, dodecanedicarboxylic acid and the like. A preferred combination is an equimolar salt of hexamethylenediamine and adipic acid.

Examples of the aromatic dicarboxylic acid include terephthalic acid, isophthalic acid and naphthalenedicarboxylic acid, and a preferable combination is an equimolar salt of hexamethylenediamine and terephthalic acid.

The aliphatic forming monomer has 6 to 6 carbon atoms.
12 aminocarboxylic acids and lactams having 6 to 12 carbon atoms, such as 6-aminocaproic acid, 7-aminoheptanoic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid, α-pyrrolidone, ε-caprolactam, laurolactam , Ε-enanthlactam and the like, 6-
Aminocaproic acid, 12-aminododecanoic acid, ε-caprolactam and laurolactam are preferred. The aliphatic polyamide-forming monomer can be used not only as a single component but also as a mixture of two or more components.

The amounts of these used are 30 to 70% by weight of equimolar salt of hexamethylenediamine and adipic acid, 70 to 30% by weight of equimolar salt of hexamethylenediamine and terephthalic acid, and 0 to 15% by weight of aliphatic polyamide-forming monomer. %, Preferably 35 to 55% by weight of equimolar salt of hexamethylenediamine and adipic acid, 65 to 45% by weight of equimolar salt of hexamethylenediamine and terephthalic acid, and 0 to 10% by weight of aliphatic polyamide forming monomer. is there.

The degree of polymerization of the crystalline polyamide resin in the present invention is not particularly limited, but 1 g of the polymer is dissolved in 100 ml of 96% concentrated sulfuric acid, and the relative viscosity measured at 25 ° C. is 1.8 to 5.0. It is preferable, and it is more preferably 2.0 to 3.0. If the relative viscosity is higher than the upper limit of the above numerical value, the workability is significantly impaired, and if it is lower than the lower limit, the mechanical strength is lowered, which is not preferable.

The method for producing a polyamide resin according to the present invention, in which the amino end group concentration is higher than the carboxyl end group concentration, comprises:
Although it is not particularly limited, it can be obtained by incorporating a diamine compound at the time of polymerization or when the composition is extrusion-kneaded after the completion of the polymerization. If it is produced during melt polymerization, a method of polymerizing by adding an excess of a diamine monomer at the time of charging the raw material, a method of polymerizing by adding a raw material monomer and a diamine compound other than the raw material monomer at the time of charging the raw material, and polymerizing a polyamide having a predetermined molecular weight After that, a method is used in which the diamine compound is added immediately before the polymer is extracted from the polymerization tank so as to achieve the desired end group concentration balance. If it is produced after the polymerization, a method in which the polyamide resin after the polymerization and the diamine compound are melt-kneaded so as to achieve the desired end group concentration balance is used.

Specific examples of the diamine compound include, in addition to those used as a monomer of the above-mentioned polyamide resin, an aliphatic diamine such as methylenediamine, ethylenediamine and trimethylenediamine, and an aromatic diamine such as naphthalenediamine and metaxylylenediamine. Diamine is used, preferably hexamethylenediamine, dodecamethylenediamine, and metaxylylenediamine.

The polyamide resin of the present invention may also contain a layered silicate. Examples of the layered silicate include a layered phyllosilicate composed of a layer of magnesium silicate or aluminum silicate.

Specific examples of the layered phyllosilicates include smectite clay minerals such as montmorillonite, saponite, pyriderite, nontronite, hectorite, stipunsite, vermiculite and halosite. These may be natural products or synthetic products. Of these, montmorillonite is preferred.

It is desirable that the layered silicate be uniformly dispersed in the polyamide resin. The state in which the layered silicate is uniformly dispersed means that the length of one side is 0.002-1.
That is, when the layered silicate having a thickness of 6 μm and a thickness of 6 to 20 Å is dispersed in the polyamide resin, each of them has an average interlayer distance of 20 Å or more and is uniformly dispersed. Here, the interlayer distance refers to the distance between the centers of gravity of the flat silicate slabs, and the term “uniformly distributed” means that the flat silicate slabs have an average of 5 or less layers in parallel or randomly. Alternatively, it means a state where 50% by weight or more, and preferably 70% by weight or more of the particles are randomly mixed with parallel particles and dispersed without forming a local lump.

When the layered silicate is a multilayered clay mineral, an amine such as dioctadecylamine, phenylenediamine, an amino acid such as 4-amino-n-butyric acid, 12-aminododecanoic acid or ε-caprolactam can be used. It is also possible to preliminarily spread the layers by contacting with a swelling agent for such lactams to facilitate incorporation of the monomer between the layers, and then polymerize and uniformly disperse the monomers. Also, using a swelling agent,
Alternatively, a method may be employed in which the interlayer is expanded to 20 liters or more in advance, and this is melt-mixed with the polyamide resin and uniformly dispersed.

The polyamide resin of the present invention can be used as it is as a fuel component, but as long as its purpose is not impaired, a heat-resistant agent, a weathering agent, a crystal nucleating agent, a crystallization accelerator,
Functionalizing agents such as a release agent, a lubricant, an antistatic agent, a flame retardant, a flame retardant aid, and a coloring agent can be used.

More specifically, as heat-resistant agents, hindered phenols, phosphites, thioethers,
Examples thereof include copper halides, which can be used alone or in combination. Examples of the weather resistance agent include hindered amines and salicylates, which can be used alone or in combination. As a crystal nucleating agent, talc,
Examples thereof include inorganic fillers such as clay and organic crystal nucleating agents such as fatty acid metal salts, which can be used alone or in combination. Examples of the crystallization accelerator include low molecular weight polyamides, higher fatty acids, higher fatty acid esters and higher aliphatic alcohols, which can be used alone or in combination. As the release agent, fatty acid metal salts,
Examples thereof include fatty acid amides and various waxes, which may be used alone or in combination. Examples of the antistatic agent include aliphatic alcohols, aliphatic alcohol esters and higher fatty acid esters, which may be used alone or in combination. As the flame retardant, metal hydroxide such as magnesium hydroxide, phosphorus, ammonium phosphate, ammonium polyphosphate, melamine cyanurate,
Ethylene dimelamine dicyanurate, potassium nitrate, brominated epoxy compound, brominated polycarbonate compound,
Brominated polystyrene compounds, tetrabromobenzyl polyacrylate, tribromophenol polycondensates, polybromobiphenyl ethers and chlorine-based flame retardants,
They can be used alone or in combination. Among these, it is preferable to add a moldability improving agent such as a release agent, a lubricant, a crystal nucleating agent and the like.

Other thermoplastic resins may be added to the polyamide resin of the present invention within the range not impairing the object of the present invention. Examples of thermoplastic resins used in combination are polyethylene, polypropylene, polystyrene, ABS resin, AS
Examples include general-purpose resin materials such as resins and acrylic resins, polycarbonate, polyphenylene oxide, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, and other high heat resistant resins. Particularly when polyethylene or polypropylene is used in combination, it is desirable to use those modified with maleic anhydride, a glycidyl group-containing monomer or the like.

A fuel part made of a crystalline polyamide resin having an amino terminal group concentration> carboxyl terminal group concentration of the present invention is bonded to a fuel tank by using a polyolefin resin modified with an unsaturated carboxylic acid or its derivative as an intermediate adhesive layer. To be done. Specifically, first, the amino terminal group concentration>
A crystalline polyamide resin having a carboxyl end group concentration and a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof are welded, and then this accessory is joined to a fuel tank.

Polyolefin resins modified with unsaturated carboxylic acids or their derivatives include polyethylene,
Ethylene / α-olefin copolymer, ethylene / α, β
-Unsaturated carboxylic acid ester-based copolymers, ethylene / vinyl acetate partially saponified copolymers, and polymers obtained by graft-polymerizing an unsaturated carboxylic acid or a derivative thereof with the above-mentioned copolymer are mentioned.

The ethylene / α-olefin copolymer is a polymer obtained by copolymerizing ethylene and an α-olefin having 3 or more carbon atoms. Examples of the α-olefin having 3 or more carbon atoms include propylene and butene-1. , Hexene-1, decene-1, 4-methylbutene-1, 4-methylpentene-1
Are preferred, and propylene and butene-1 are preferred.

The ethylene / α, β-unsaturated carboxylic acid ester-based copolymer is a polymer obtained by copolymerizing ethylene and an α, β-unsaturated carboxylic acid ester monomer.
Examples of unsaturated carboxylic acid ester monomers include acrylic acid esters such as methyl acrylate, ethyl acrylate, propyl acrylate, and butyl acrylate, methyl methacrylate, ethyl methacrylate, propyl methacrylate,
Methacrylic acid esters such as butyl methacrylate can be mentioned. Preferable examples include ethylene / ethyl acrylate copolymers and ethylene / methyl methacrylate copolymers, which can be obtained at low cost and have excellent thermal stability.

The ethylene / vinyl acetate partially saponified copolymer is a compound obtained by partially saponifying an ethylene / vinyl acetate copolymer. By subjecting the ethylene / vinyl acetate copolymer to saponification by a known saponification method, for example, a method in which a low boiling alcohol such as methanol or ethanol and an alkali such as sodium hydroxide, potassium hydroxide or sodium methylate are treated. It is possible to obtain an ethylene / vinyl acetate partially saponified copolymer.

As the unsaturated carboxylic acid or its derivative to be graft-polymerized, acrylic acid, methacrylic acid,
Ethacrylic acid, maleic acid, fumaric acid, itaconic acid,
Unsaturated carboxylic acids such as citraconic acid and nadic acid or derivatives thereof, such as acid halides, amides, imides,
Examples thereof include anhydrides and esters. Specific examples of the derivative include maleenyl chloride, maleimide, maleic anhydride,
Examples include monomethyl maleate and dimethyl maleate. Among these, unsaturated dicarboxylic acids or their anhydrides are preferable, and maleic acid, nadic acid or their acid anhydrides are particularly preferably used. Also,
The modified polyolefin resin is a known production method, for example,
A method of reacting an unmodified polyolefin resin with an unsaturated carboxylic acid in a molten state, a method of reacting in a solution state,
It can be produced by any of a method of reacting in a slurry state, a method of reacting in a gas phase state and the like.

The method of welding a crystalline polyamide resin having an amino terminal group concentration> a carboxyl terminal group concentration and a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof is first modified with an unsaturated carboxylic acid or a derivative thereof. After molding the polyolefin resin, a crystalline polyamide resin having an amino terminal group concentration> a carboxyl terminal group concentration is injection-molded, and both molded products are welded together.

Specific examples of the welding method include vibration welding method, injection welding method such as die slide injection (DSI), die rotary injection (DRI) and two-color molding, ultrasonic welding method, spin welding method, hot plate welding method. , A heat wire welding method, a laser welding method, a high frequency induction heating welding method, and the like.

It is desirable that the temperature of the molding resin at the time of welding by the injection welding method such as DSI, DRI and two-color molding is 250 ° C. to 320 ° C., preferably 270 ° C. to 300 ° C. The mold temperature at that time is 30 ° C to 120 ° C, preferably 50 ° C to 100 ° C.
Is desirable.

Examples of the fuel component of the present invention include components such as valves attached to the fuel tank, a fuel hose joint, a canister connecting nozzle, a separator and the like.

[0037]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The physical properties of the molded articles in the examples and comparative examples were measured as follows.

[Measurement of Polyamide Resin End Group Concentration] The amino end group concentration was measured by dissolving 1 g of polyamide in a phenol / methanol mixed solution and titrating with 0.02N hydrochloric acid. Carboxyl end group concentration is 1g of polyamide
Was dissolved in benzyl alcohol and titrated with a 0.05N sodium hydroxide solution for measurement.

[Fuel Permeation Coefficient] According to JIS Z0208, a fuel permeation test was carried out at a measurement atmosphere temperature of 60 ° C. using a test piece of φ75 mm and a thickness of 1 mm molded by injection molding. The fuel is isooctane and toluene in a volume ratio of 1:
Fuel C used as 1 was mixed with 10% of ethanol and used. Further, the fuel permeation measurement sample surface was installed with the permeation surface facing downward so that the fuel always contacted.

[Tensile Strength] According to ASTM D638,
Using a No. 1 test piece with a thickness of 3.2 mm, a pulling rate of 5 per minute
mm.

[Initial Bonding Strength] With the shape of the test piece shown in FIG. 1, the interface between the parts 1 and 2 is melt-bonded at the time of injection welding to obtain one test piece. As the test piece, first, a metal piece having the shape of the component 2 in FIG. 1 was inserted into a mold, and the component 1 was molded using polyethylene modified with maleic anhydride. Next, after cooling the component 1 sufficiently, insert it into the mold,
A joined test piece was obtained by molding the part of the component 2 using the resin to be evaluated. This test piece was peeled from the boundary surface at a pulling speed of 50 mm / min, or the maximum tensile strength until it was broken at a portion other than the boundary surface (breakage of the base material) was measured and evaluated as the initial adhesive strength.

[Adhesive Strength After Fuel Immersion] A test piece molded by the same procedure as in the evaluation of the initial adhesive strength is put into an autoclave, and a fuel mixture of Fuel C + methanol 15% is enclosed until the test piece is completely immersed. 6 autoclaves
It was left to stand in a 0 ° C. warm water tank for 350 hours. The maximum tensile strength of the test piece taken out thereafter was evaluated as the adhesive strength after immersion in fuel.

Example 1 ε-as a polymerization monomer was added to 70 liters of autoclave.
20 kg of caprolactam, 0.5 kg of water, 1/290 of meta-xylylenediamine (eq / mol lactam)
The inside of the tank was replaced with nitrogen, and then heated to 100 ° C. and stirred so that the inside of the tank became uniform. Then, the inside of the tank was polymerized at 260 ° C. and 1.7 MPa, and the obtained polymer was used as a sample by extracting unreacted monomer in 100 ° C. hot water. The obtained polyamide 6 has a relative viscosity of 2.50,
The amino end group concentration was 90 meq / kg. Cylinder temperature 270 ° C., mold temperature 80
Injection molding was performed at ℃, and the tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Furthermore, using a 1t plate molded under the same molding conditions, JIS
A fuel permeation test based on Z0208 was conducted. The obtained results are shown in Table 1.

Example 2 In Example 1, 1/35 of metaxylylenediamine was added.
Polyamide 6 was obtained in the same manner as in Example 1 except that 0 (eq / mol lactam) was used. The resulting polyamide 6 had an amino terminal group concentration of 60 meq / kg. Cylinder temperature 270 ℃, mold temperature 80 ℃ obtained pellets
Was injection-molded and the tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Furthermore, using a 1t plate molded under the same molding conditions, JIS
A fuel permeation test based on Z0208 was conducted. The obtained results are shown in Table 1.

Example 3 In Example 1, 1/20 of metaxylylenediamine was added.
Polyamide 6 was obtained in the same manner as in Example 1 except that 0 (eq / mol lactam) was used. The obtained polyamide 6 had an amino terminal group concentration of 110 meq / kg. Cylinder temperature 270 ° C., mold temperature 80
Injection molding was performed at ℃, and the tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Furthermore, using a 1t plate molded under the same molding conditions, JIS
A fuel permeation test based on Z0208 was conducted. The obtained results are shown in Table 1.

Example 4 In a 70 liter autoclave, 4 kg of water and 20% of laurolactam as polymerized monomers and 1/300 (eq / mol laurolactam) of metaxylylenediamine were used.
So that the inside of the tank is replaced with nitrogen, then 180 ° C
It was heated up to and stirred so that the inside of the tank became uniform. Then, after pre-polymerizing the inside of the tank at 280 ° C. and 3.0 MPa, the temperature is lowered to 250 ° C. while releasing the pressure to atmospheric pressure,
Post-polymerization was carried out at 0 ° C. under a nitrogen stream. The polyamide 12 thus obtained has a relative viscosity of 2.05 and an amino end group concentration of 60.
It was milliequivalent / kg. The obtained pellets are injection molded at a cylinder temperature of 270 ° C and a mold temperature of 80 ° C, and then AST
M-compliant tensile test pieces were evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Further, a fuel permeation test based on JIS Z0208 was conducted using a 1t plate molded under the same molding conditions. The obtained results are shown in Table 1.

Example 5 In Example 4, 1/480 of meta-xylylenediamine was added.
Example 4 except that (eq / mol laurolactam) was used.
Polyamide 12 was obtained in the same manner as. The amino terminal group concentration of the obtained polyamide 12 was 50 meq / kg. The obtained pellets were injection molded at a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C., and a tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Further, a fuel permeation test based on JIS Z0208 was performed using a 1t plate molded under the same molding conditions. The obtained results are shown in Table 1.

Example 6 In Example 4, 1/250 of metaxylylenediamine was added.
Example 4 except that (eq / mol laurolactam) was used.
Polyamide 12 was obtained in the same manner as. The amino terminal group concentration of the obtained polyamide 12 was 80 meq / kg. The obtained pellets were injection molded at a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C., and a tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Further, a fuel permeation test based on JIS Z0208 was conducted using a 1t plate molded under the same molding conditions. The obtained results are shown in Table 1.

Comparative Example 1 In Example 1, 1/40 of metaxylylenediamine was added.
Polyamide 6 was obtained in the same manner as in Reference Example 1 except that 0 (eq / mol lactam) was used. The resulting polyamide 6 had an amino terminal group concentration of 50 meq / kg. Cylinder temperature 270 ℃, mold temperature 80 ℃ obtained pellets
Was injection-molded and the tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Furthermore, using a 1t plate molded under the same molding conditions, JIS
A fuel permeation test based on Z0208 was conducted. The obtained results are shown in Table 1.

Comparative Example 2 Metaxylylenediamine was added to 1/300 in Example 4.
Polyamide 12 was obtained in the same manner as in Example 4 except that 0 (eq / mol laurolactam) was used. The amino terminal group concentration of the obtained polyamide 12 was 40 meq / kg. The obtained pellets were injection molded at a cylinder temperature of 270 ° C. and a mold temperature of 80 ° C., and a tensile test piece conforming to ASTM was evaluated. Further, the initial adhesive strength and the adhesive strength after the fuel immersion of the test piece molded at the secondary injection molding cylinder set temperature of 270 ° C. and the mold temperature of 80 ° C. in the procedure of FIG. 1 were measured. Further, a fuel permeation test based on JIS Z0208 was conducted using a 1t plate molded under the same molding conditions. The obtained results are shown in Table 1.

Comparative Example 3 Polyethylene modified with maleic anhydride was injection molded at a cylinder temperature of 190 ° C. and a mold temperature of 40 ° C. to obtain AST.
M-compliant tensile test pieces were evaluated. Further, a fuel permeation test based on JIS Z0208 was conducted using a 1t plate molded under the same molding conditions. The obtained results are shown in Table 1.

[0052]

[Table 1]

[0053]

EFFECTS OF THE INVENTION The fuel component of the present invention has excellent fuel permeation resistance and fuel resistance at the welded portion, and particularly excellent fuel resistance at the welded portion over a long period of time. It can be suitably used as a component.

[0054]

[Brief description of drawings]

FIG. 1 is a diagram showing a shape of a test piece for evaluating adhesive strength.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI // B29K 23:00 B29K 77:00 77:00 B29L 31:20 B29L 31:20 C08L 77:00 C08L 77:00 B60K 15 / 02 (58) Fields surveyed (Int.Cl. ⁷ , DB name) C08J 5/00-5/24 C08G 69/00-69/50 C08L 77/00-77/12 B60K 15/00-15/10

Claims (7)

(57) [Claims] 1. A fuel tank, a fuel hose, and a canister, which are made of a crystalline polyamide resin having an amino terminal group concentration> a carboxyl terminal group concentration and are excellent in fuel resistance of a welded portion.
Parts that come with one of the parts. 2. The component according to claim 1, wherein the amino end group concentration is 50 meq or more per kg of polymer. 3. The component according to claim 1, wherein the crystalline polyamide resin is an aliphatic polyamide resin composed of an aliphatic diamine and an aliphatic dicarboxylic acid or a lactam or an aminocarboxylic acid. 4. The component according to claim 1, wherein the crystalline polyamide resin is a crystalline semi-aromatic polyamide resin containing at least one aromatic monomer component. 5. A fuel tank, fuel hose, and canister made of a crystalline polyamide resin having an amino terminal group concentration> a carboxyl terminal group concentration and having excellent fuel resistance in the welded portion.
Materials for parts that come with any of the parts. 6. A crystalline polyamide resin having a concentration of amino end groups> a concentration of carboxyl end groups and a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof are welded to each other, which is excellent in fuel resistance of a welded portion , Fuel tank
Parts that come with either the fuel, fuel hose, or canister . 7. Molding a polyolefin resin modified with an unsaturated carboxylic acid or a derivative thereof, and then injection-molding a crystalline polyamide resin having a concentration of amino end groups> a concentration of carboxyl end groups to weld both molded products. With excellent fuel resistance at the welded part ,
Manufacturing method of parts attached to either hose or canister .