JP3036666B2 - Resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyamide resin composition having excellent properties in all of physical properties, environmental resistance properties and antistatic properties.
The present invention relates to a fuel-related component of an automobile having excellent creep characteristics, gasoline resistance, alcohol gasoline resistance, sour gasoline resistance, road anti-freezing agent resistance, antistatic characteristics and the like.

[0002]

2. Description of the Related Art Conventionally, polyamide resins have been frequently used for fuel tubes, fuel connectors, fuel filler necks, and the like as fuel components for automobiles. However, recently, the use conditions of these parts have become severe, and improvements in strength and creep characteristics have been demanded.Also, in addition to the conventional required properties such as gasoline resistance and road deicing resistance, alcohol gasoline resistance,
New required properties such as sour gasoline resistance and antistatic properties are increasing, and conventional polyamide resins and reinforced materials are no longer compatible.

In particular, the destruction of a fuel line and the ignition of gasoline by an electrostatic spark have recently been regarded as a problem. This is because when the fuel flows through the tube, it generates static electricity at the contact surface with the tube, filter and connector, which accumulates locally and sparks on the outer surface by some trigger, destroying the tube etc. Alternatively, it ignites gasoline and has the danger of a major accident.

This is because, in addition to the recent increase in the flow rate of gasoline in the fuel line, an increase in the bent portion of the line, and an increase in the portion where the flow speed changes rapidly,
This is because many resin parts, including resin lines, have begun to be used to reduce the weight and cost of fuel lines.

[0005] As a countermeasure, it has been proposed that a multi-layered tube using conductive fluorine is used for the inner surface of the fuel line, and several proposals have been made. However, for those manufactured by injection molding, it is difficult to take a multilayer structure, and at present, this solution has not been solved yet.

[0006] Further, there is also a demand for improved performance of resistance to recently oxidized gasoline. As described above, a number of required characteristics such as strength, creep characteristics, gasoline resistance, alcohol gasoline resistance, sour gasoline resistance, road anti-freezing agent resistance, antistatic characteristics are required, and all these requirements are satisfied. At present, no material has been developed.

[0007]

An object of the present invention is to provide a polyamide resin composition having excellent properties in all of physical properties, environmental resistance properties and antistatic properties, and to provide strength, creep properties, gasoline resistance and alcohol-resistant gasoline. It is an object of the present invention to provide a fuel-related part of an automobile having excellent properties, anti-freezing agent property, antistatic property and the like.

[0008]

According to the present invention, there is provided a resin composition comprising a polyamide 11 resin or a polyamide 12 resin, carbon fiber, and glass fiber. Characteristics and gasoline resistance,
An object of the present invention is to provide a fuel-related part of an automobile having excellent resistance to alcohol gasoline, resistance to road deicing, and antistatic properties.

The polyamide 11 resin (A) of the polyamide 11 resin or the polyamide 12 resin used in the present invention is defined by a structural formula (-) having an acid amide bond (-CONH-).
CO (CH ₂₎ a polyamide resin represented by ₁₀ NH-) _n, obtained by polymerizing 11-aminoundecanoic acid or undecapeptide lactam.

The polyamide 12 resin of the polyamide 11 resin or polyamide 12 resin (A) used in the present invention refers to a structural formula (-) having an acid amide bond (-CONH-).
CO (CH _{2) 11} NH-) is a polyamide resin represented by _n, is obtained by polymerizing 12-aminododecanoic acid or dodecalactam the (laurolactam).

The melting properties of the polyamide 11 resin or polyamide 12 resin used in the present invention are not particularly limited, but those having excellent fluidity are preferable in consideration of injection molding. However, it is not preferable that the physical properties are reduced with an emphasis on fluidity, and the range of the relative viscosity (98% sulfuric acid method) measured according to JIS K6810 is as follows.
Those with 1.80 to 2.60 are preferred. If the relative viscosity value is lower than 1.80, physical properties such as impact strength are deteriorated. If the relative viscosity value is higher than 2.60, the flow characteristics in manufacturing parts by injection molding are deteriorated, and short shots are caused. It is not preferable because the surface condition becomes poor and the surface condition deteriorates.

The mixing ratio of the polyamide 11 resin or the polyamide 12 resin used in the present invention is suitably 55 to 90% by weight, and preferably 60 to 85% by weight. The compounding ratio of the polyamide 11 resin or the polyamide 12 resin is 55
When the content is less than 85% by weight, the specific gravity is increased, which is not preferable in terms of weight reduction. When the content is more than 85% by weight, the rigidity of the composition is lowered, and also the creep resistance is deteriorated and the bonding with a tube or the like is deteriorated. Absent.

As the carbon fiber (B) used in the present invention, pitch-based or PAN-based carbon fibers can be used without any limitation, but PAN-based carbon fibers are more preferable in view of properties such as physical properties and conductivity. The diameter of the carbon fiber is not limited, but is preferably 5 to 15 μm.

The compounding ratio of the carbon fibers used in the present invention is 5 to 5.
20% by weight is suitable, preferably 7 to 17% by weight. When the compounding ratio of the carbon fiber is 5% by weight or less, good conductivity (10 ¹⁰ Ωcm or less) cannot be obtained, which is not preferable.
If the compounding ratio is 20% by weight or more, the fluidity of the composition deteriorates, which causes short shots and deteriorates the surface state, which is not preferable.

The glass fiber (C) used in the present invention comprises:
There is no particular limitation. The glass fiber diameter is not limited, but is preferably 5 to 15 μm.

The compounding ratio of the glass fibers used in the present invention is 5
~ 25% by weight is suitable, preferably 7-23% by weight
It is. If the mixing ratio of the glass fibers is 5% by weight or less, the rigidity is lowered, the creep resistance is also deteriorated, and the bonding with a tube or the like is deteriorated. On the other hand, if the compounding ratio is 25% by weight or more, the fluidity of the composition deteriorates, which causes short shots and deteriorates the surface state, which is not preferable.

Although there is no particular limitation on the method for producing the composition of the present invention, a polyamide 11 resin or a polyamide 12 resin, carbon fibers and glass fibers are preliminarily blended, and the mixture is fed to a hopper of a single screw or twin screw extruder. Injection and melt kneading, or injection of polyamide 11 resin or polyamide 12 resin into the hopper of a single screw or twin screw extruder, melting in the extruder, and then feeding carbon fiber and glass fiber from the melting zone in the middle of the extruder And melt kneading.

The method of injection molding the composition of the present invention is not particularly limited, and the composition can be molded by a usual injection molding machine.

[0019]

The present invention will be described in more detail with reference to the following Examples and Comparative Examples, which should not be construed as limiting the present invention. It should be understood that various changes, modifications, and improvements can be made to the present invention in addition to the following embodiments without departing from the spirit of the present invention.

Example 1 Relative viscosity according to JIS K6810 (98% sulfuric acid method)
1.95 polyamide 12 resin (UBE nylon 301)
4B; Ube Industries, Ltd.) 70.0% by weight and fiber diameter 7μ
m carbon fiber (Vesfight HTA-C6NR; manufactured by Toho Rayon Co., Ltd.) and glass fiber having a fiber diameter of 13 μm (ECS T-24; manufactured by NEC Corporation)
A total of 10 kg was put into an 18-liter can so as to be 20.0% by weight, and the mixture was rotated and blended by a blender for 5 minutes.

The obtained mixture is kneaded with a twin-screw kneader PCM-45 manufactured by Ikegai Iron Works Co., Ltd. at a cylinder setting temperature of 250 ° C. and a rotation speed of 150 rpm at a discharge rate of 15 kg / hr, and then heated and dried under vacuum. The desired composition was obtained.

The obtained composition was molded into test pieces conforming to ASTM using an injection molding machine (N-140BII, manufactured by Nippon Steel Works), and the physical properties in the table were measured. The volume specific resistance value is 70 mm in length and 12.7 mm in width.
A conductive paint was applied to the end surface of the test piece having a thickness of 3 mm, and the resistance value was measured during the application to calculate the volume specific resistance value.

The formability was determined by visually observing the surface smoothness on the opposite side of the gate when the ASTM tensile test piece was formed.

The oxidized gasoline property was evaluated by adding 0.1 ml of a mixed solution of 600 ml of toluene and 600 ml of isooctane.
An oxidized gasoline solution containing 1 g of tertiary butyl peroxide and 0.01 g of copper stearate was heated to 60 ° C., and 30 test pieces for tensile or volume resistivity measurement were immersed in the solution. And the change in physical properties for 30 days was measured.

The calcium chloride resistance was evaluated by impregnating a 12 mm saturated aqueous solution of calcium chloride on a previously formed tensile test piece based on ASTM D-638.
A cycle in which gauze at the corner was placed and left in an oven at 120 ° C. for 2 hours was repeated 10 times, and the surface was observed with a microscope to observe the presence or absence of cracks. (The gauze impregnated with the saturated aqueous solution of calcium chloride is replaced every cycle.)

Of these evaluation results, a tensile strength of 1,0
It can be said that those having a weight of 00 kg / cm ² or more have sufficient creep resistance as a connector for a fuel line, a filter for a fuel or a part for fuel injection, and have no cracks in a calcium chloride resistance test. If the impact strength is 10 kg · cm / cm or more, it can be said that the environment properties such as anti-freezing agent and stepping stone on the road are excellent. Further, the tensile strength after the oxidation gasoline resistance treatment is 50.
Those having 0 kg / cm ² or more can be said to have resistance to all kinds of gasoline. Furthermore, if the volume specific resistance value is 10 ⁸ Ω · cm or less, and even if it is 10 ⁸ Ω · cm or less even after oxidation gasoline resistance treatment, it can be said that excellent antistatic properties are exhibited in all environments.

Example 2 In Example 1, a polyamide 12 resin (UB) having a relative viscosity of 2.25 according to JIS K6810 (98% sulfuric acid method) was used.
E-Nylon 3024B; Ube Industries, Ltd.) with a twin-screw kneader PCM-45 manufactured by Ikegai Iron Works Co., Ltd. Cylinder set temperature 250 ° C. Rotation speed 150 rpm Feed amount 7.7 kg
/ Hr, carbon fiber (Vesfight HTA-C6NR; manufactured by Toho Rayon Co., Ltd.) at a charge of 1.0 kg / hr from the middle of the cylinder of the extruder, and a charge of 1.3 kg / hr. Glass fiber (ECS T-24;
An experiment was carried out in the same manner as in Example 1 except that a composition was obtained by adding and kneading the mixture (manufactured by Nippon Electric Glass Co., Ltd.). The content of carbon fibers was 10% by weight, and the content of glass fibers was 13% by weight. The results are shown in Table 1.

Example 3 In Example 2, the feed rate of the polyamide 12 resin was 7.0 kg / hr, and the feed rate of the carbon fiber was 1.5 kg / h.
An experiment was performed in the same manner as in Example 2 except that the amount of r and the glass fiber input was 1.5 kg / hr. The content of carbon fibers was 15% by weight, and the content of glass fibers was 15% by weight. The results are shown in Table 1.

Example 4 In Example 2, the polyamide 12 resin was replaced with the polyamide 11
Resin (BMNO; manufactured by ATOCHEM; relative viscosity 2.0)
An experiment was performed in the same manner as in Example 2 except that 3) was used. The content of carbon fibers was 10% by weight, and the content of glass fibers was 13% by weight. The results are shown in Table 1.

[0030]

[Table 1]

Comparative Example 1 The same experiment as in Example 1 was conducted, except that conductive carbon black was used instead of carbon fiber and the blend ratio was adjusted so that the content was 8% by weight. The results are shown in Table 2.

Comparative Example 2 In Example 2, brass fiber having a fiber diameter of 80 μm was used in place of carbon fiber, and the amount charged into the extruder was adjusted so that the content was 59% by weight, and no glass fiber was charged. The same experiment as in Example 2 was performed except for the above. The results are shown in Table 2.

Comparative Example 3 An experiment was conducted in the same manner as in Example 1 except that glass fiber was not used and the blend ratio of carbon fibers was 30% by weight. The results are shown in Table 2.

Comparative Example 4 The same experiment as in Example 1 was performed, except that the glass fiber was not used and the blend ratio of the glass fiber was 23% by weight. The results are shown in Table 2.

[0035]

[Table 2]

Comparative Example 5 Polyamide 6 resin (1015B manufactured by Ube Industries, Ltd .; Relative viscosity =
The same experiment as in Example 2 was performed except that 2.78) was used. The results are shown in Table 3.

Comparative Example 6 The same experiment as in Example 3 was carried out except that polyamide 66 resin (2015B manufactured by Ube Industries, Ltd .; relative viscosity = 2.50) was used instead of polyamide 12 resin. . The results are shown in Table 3.

Comparative Example 7 The same experiment as in Example 2 was carried out except that the amount of carbon fiber was set to 4% by weight and the amount of glass fiber was set to 21% by weight, and the amount of addition to the extruder was adjusted. Was done. The results are shown in Table 3.

Comparative Example 8 An experiment was carried out in the same manner as in Example 2 except that the content to the extruder was adjusted so that the carbon fiber content was 25% by weight and the glass fiber content was 5% by weight. Was done. The results are shown in Table 3.

[0040]

[Table 3]

COMPARATIVE EXAMPLE 9 The same experiment as in Example 2 was carried out except that the carbon fiber content was adjusted to 10% by weight and the glass fiber content was adjusted to 4% by weight. Was done. The results are shown in Table 4.

Comparative Example 10 An experiment was performed in the same manner as in Example 2 except that the carbon fiber content was set to 3% by weight and the glass fiber content was adjusted to 27% by weight, and the amount charged into the extruder was adjusted. went. The results are shown in Table 4.

[0043]

[Table 4]

[0044]

According to the present invention, there is provided a resin composition of a polyamide resin having excellent properties in all of physical properties, environmental resistance properties, and antistatic properties, strength, creep properties, gasoline resistance, alcohol gasoline resistance, It is possible to provide a fuel-related part of an automobile which is excellent in anti-road anti-freezing property, anti-static property and the like.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08K 7:14)

Claims (2)

(57) [Claims] (A) 55 to 90% by weight of a polyamide 11 resin or a polyamide 12 resin, and (B) a carbon fiber
A resin composition for injection molding for automobile fuel-related parts, comprising 20% by weight and (C) 5 to 25% by weight of glass fiber. 2. The resin composition according to claim 1, wherein the vehicle fuel-related parts are fuel line connectors, fuel filters, or fuel injection parts.