JPH05117376A - Automobile part - Google Patents

Abstract

PURPOSE:To provide an automobile part made of a polybutylene naphthalenedicarboxylate, to be used as a part contacting with fuel, oil and combustion gas and having excellent chemical resistance, oil resistance, gasoline resistance, etc. CONSTITUTION:The objective automobile part to be used as a part contacting with fuel and/or oil is made of a polybutylene naphthalenedicarboxylate, preferably polybutylene-2,6-naphthalenedicarboxylate. The resin may be used as a part contacting with combustion gas.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a polybutylene naphthalene dicarboxylate (hereinafter abbreviated as PBN) and is an automobile part used in a portion in contact with fuel and / or oil or in a portion in contact with combustion gas. More specifically, mechanical strength, dimensional accuracy, heat resistance, heat aging resistance, chemical resistance, gasoline resistance, hot water resistance,
This relates to automobile parts with excellent durability such as alkali resistance.

[0002]

2. Description of the Related Art Many kinds of materials such as metal, glass, rubber and plastics are used in automobiles. Among them, thermoplastics have been gradually used in recent years because of weight saving of vehicles, great freedom of design, high productivity and easy cost reduction.

General-purpose plastics such as polyethylene and polypropylene have been used from a relatively early stage for automobile parts having moderately required characteristics. However, because parts that are used under severe conditions such as high temperature and high humidity such as engine rooms are being replaced by plastics, engineering plastics such as polyamide, polyacetal, polybutylene terephthalate (hereinafter abbreviated as PBT) are being used. Are becoming more popular.

In particular, when used in a portion in contact with fuel, various oils, combustion gas, etc., the material is required to have chemical resistance, oil resistance, gasoline resistance, hot water resistance, alkali resistance, acid resistance and the like. It

Each engineering plastic has excellent characteristics, but also has drawbacks. For example, although polyamide has excellent mechanical properties, heat resistance, oil resistance, gasoline resistance, moldability, etc., it has a high water absorption rate, so dimensional changes due to water absorption and a reduction in mechanical strength are large,
Another problem is that stress cracks are generated by the metal salt. Although PBT has excellent mechanical properties, heat resistance, heat aging resistance, electrical characteristics, chemical resistance, and moldability,
Since hot water resistance and alkali resistance are not good, some parts may not be adopted because of low reliability. These characteristics are manifested because they have the primary structure of the polymer and characteristic groups such as amide groups and ester groups, so even if attempts are made to improve the drawbacks by using additives or polymer blending, it is the Cannot be an effective solution.

Therefore, the inventor of the present invention aims to obtain automobile parts which are excellent in mechanical strength, dimensional accuracy, heat resistance, heat aging resistance, chemical resistance, oil resistance, gasoline resistance, hot water resistance, and alkali resistance. As a result of intensive studies on the material, the present invention has been achieved.

[0007]

SUMMARY OF THE INVENTION The present invention is an automobile part using PBN, which is used in a portion in contact with fuel and / or oil or in a portion in contact with combustion gas.

In the present invention, PBN is a polyester having naphthalenedicarboxylic acid, preferably naphthalene-2,6-dicarboxylic acid as a main acid component and 1,4-butanediol as a main glycol component, that is, all repeating units or The majority (usually 90 mol% or more, preferably 95 mol% or more) is a butylene naphthalene dicarboxylate polyester.

Further, this polyester can be copolymerized with the following components as long as the physical properties are not impaired. That is, as the acid component, an aromatic dicarboxylic acid other than naphthalenedicarboxylic acid, for example, phthalic acid, isophthalic acid, terephthalic acid, diphenyldicarboxylic acid, diphenyletherdicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylmethanedicarboxylic acid, diphenylketonedicarboxylic acid, Examples thereof include diphenyl sulfide dicarboxylic acid, diphenyl sulfone dicarboxylic acid, aliphatic dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, alicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid, tetralindicarboxylic acid and decalindicarboxylic acid.

As the glycol component, ethylene glycol, propylene glycol, trimethylene glycol,
Pentamethylene glycol, hexamethylene glycol, octamethylene glycol, neopentyl glycol, cyclohexanedimethanol, xylylene glycol, diethylene glycol, polyethylene glycol,
Examples thereof include bisphenol A, catechol, resorcinol, hydroquinone, dihydroxydiphenyl, dihydroxydiphenyl ether, dihydroxydiphenylmethane, dihydroxydiphenylketone, dihydroxydiphenylsulfide, dihydroxydiphenylsulfone and the like.

Examples of the oxycarboxylic acid component include oxybenzoic acid, hydroxynaphthoic acid, hydroxydiphenylcarboxylic acid and ω-hydroxycaproic acid.

Further, trifunctional or higher functional compounds such as glycerin, trimethylpropane, pentaerythritol, trimellitic acid, pyromellitic acid and the like can be copolymerized as long as the polyester does not substantially lose the molding performance.

Such a polyester can be obtained by polycondensing naphthalenedicarboxylic acid and / or a functional derivative thereof and butylene glycol and / or a functional derivative thereof by a conventionally known aromatic polyester production method.

The PBN polymer thus obtained may optionally contain various additives, for example, reinforcing agents having various shapes such as fibrous, plate-like, powdery and granular forms, as long as the physical properties thereof are not significantly impaired. Stabilizers, colorants, ultraviolet absorbers, mold release agents, antistatic agents, crystallization accelerators, crystal nucleating agents, fillers, impact modifiers, flame retardants, flame retardant aids and the like can be added.

When preparing a composition from the PBN polymer and these additives, it is possible to use known equipment and methods generally used as a conventional method for preparing a resin composition.

The injection molding method is the most preferable method for obtaining a molded product from PBN or a PBN composition, but other known molding methods such as an extrusion molding method, a compression molding method, a transfer molding method and a blow molding method are also available. In addition to cutting, welding, adhesion, bonding, bending, plating deposition,
It is also possible to perform secondary processing such as printing and painting. The automobile part of the present invention can be obtained by using the molded product of PBN thus obtained.

An automobile part using the PBN of the present invention is
Compared with conventional parts using polyamide, PBT, etc., the properties such as mechanical strength, dimensional accuracy, heat resistance, heat aging resistance, chemical resistance, gasoline resistance, hot water resistance, and alkali resistance are excellent.

The parts for automobiles used in the portion of the present invention contacting the fuel and / or oil, or the parts for automobiles used in the portion contacting the combustion gas are not particularly limited, but oil caps may be given as examples. , Oil filter, fuel cap, fuel strainer, tanks, cylinder head cover, various cases,
These include distributor caps, fuel injection valves, and exhaust gas valves. Next, the present invention will be further described with reference to examples.

The main characteristic measuring methods are as follows. (1) Tensile strength According to ASTM D-638. (2) Dimensional accuracy A 60 × 100 × 1.5 mm flat plate is immersed in water at 23 ° C. for 24 hours, and then the dimensional change is measured. (3) Deflection temperature under load According to ASTM D-648. (4) Heat aging resistance The tensile strength after heat treatment at 180 ° C. for 1000 hours is measured. (5) Gasoline resistance After being immersed in regular gasoline at 60 ° C for 50 days, the tensile strength is measured. (6) Hot water resistance The tensile strength after boiling water treatment at 100 ° C. for 200 hours is measured. (7) Chemical resistance After being immersed in 10% hydrochloric acid and 10% NaOH aqueous solution at 20 ° C. for 7 days, the appearance is visually judged.

[0020]

Example 1 A PBN polymer was injection molded at 270 ° C. to obtain a tensile test piece and a bending test piece. Each test piece was subjected to each of the above tests (1) to (7).

[0021]

COMPARATIVE EXAMPLE 1 A PBT polymer was injection molded at 250 ° C. and tested in the same manner as in Example 1.

[0022]

Comparative Example 2 Polyamide 66 (Asahi Kasei Leona 1402
S) was injection molded at 270 ° C. and tested in the same manner as in Example 1.

The results are summarized in Table 1.

[0024]

[Table 1]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ken Kojima 3-37-19 Oyama, Sagamihara-shi, Kanagawa Teijin Limited Sagamihara Research Center

Claims (6)

[Claims] 1. An automobile part which is made of polybutylene naphthalene dicarboxylate and which is used in a portion where fuel and / or oil comes into contact. 2. An automobile part using a polybutylene naphthalene dicarboxylate, which is used in a portion in contact with combustion gas. 3. The automobile part according to claim 1 or 2, wherein the polybutylene naphthalene dicarboxylate is polybutylene-2,6-naphthalene dicarboxylate. 4. The automobile part according to claim 1 or 2, wherein the automobile part is an oil filter. 5. The automobile part according to claim 1 or 2, wherein the automobile part is a fuel strainer. 6. The automobile part according to claim 1 or 2, wherein the automobile part is a blow-by gas valve.