JP3263978B2 - Polyamide 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 plasticity, retention and cold resistance.

[0002]

2. Description of the Related Art Polyamide has extremely excellent mechanical properties such as toughness, rigidity, impact resistance, and abrasion resistance.
Because it has excellent properties such as chemical resistance and heat resistance,
It is used for the production of molded products such as yarns, thin plates, rods, films, gears, hoses, etc. When a polyamide is used for a pressure-resistant hose or the like, it is necessary to add a plasticizer for the purpose of imparting flexibility.

Hitherto, as this type of plasticizer, dibenzyltoluenes, p-hydroxybenzoic acid esters, benzenesulfonamides and the like have been known. However, these have problems in compatibility with the polyamide, plasticization efficiency, and the like, and in particular, have a problem that the flexibility of the plasticized polyamide cannot be maintained at a low temperature.

[0004]

SUMMARY OF THE INVENTION The present invention provides a polyamide resin composition which satisfies all of the various properties of plasticity, retention and cold resistance. It is intended to be usable under the environment.

[0005]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have found that by using a p-hydroxybenzoic acid ester to which a predetermined amount of alkylene oxide has been added, the intended object has been achieved. The present inventors have found that the present invention can be achieved, and have completed the present invention based on such findings.

That is, the polyamide resin composition according to the present invention is characterized by containing a p-hydroxybenzoic acid ester represented by the general formula (1) (hereinafter referred to as “the present ester”).

Embedded image [In the formula, R represents an alkyl group, a cycloalkyl group which may have a substituent, an aryl group or an aralkyl group.
A represents an alkylene group having 2 to 4 carbon atoms. n is 1 to 20
Indicates an integer. ]

The present ester is obtained by reacting p-hydroxybenzoic acid or methyl p-hydroxybenzoate with a predetermined ether-containing alcohol (alkylene oxide adduct of an alcohol selected from aliphatic alcohols, alicyclic alcohols and aromatic alcohols). A compound obtained by ordinary esterification or transesterification with at least one species.

Examples of the aliphatic alcohol include linear or branched saturated or unsaturated alcohols.
More specifically, ethyl alcohol, butyl alcohol, amyl alcohol, hexyl alcohol, heptyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, myristyl alcohol, cetyl Alcohol, stearyl alcohol, behenyl alcohol, Alfol 610 (Vista Chemical Far East),
Saturated alcohols such as Lineball 79, 911 (Shell Chemical), Diadol 79, 911 (Mitsubishi Kasei); octenyl alcohol, undecenyl alcohol, hexadecenyl alcohol, octadecenyl alcohol, linoleyl alcohol, An unsaturated alcohol such as linolenyl alcohol is exemplified.

Examples of the alicyclic alcohol include cyclohexyl alcohol and methylcyclohexyl alcohol.

Examples of the aromatic alcohol include phenols such as benzyl alcohol, methylbenzyl alcohol, butylbenzyl alcohol and the like, phenol, cresol, octylphenol, nonylphenol and the like.

Specific examples of the alkylene oxide having 2 to 4 carbon atoms include ethylene oxide, propylene oxide, and butylene oxide.
-20. When an ester obtained from an ether-containing alcohol to which an alkylene oxide exceeding 20 mol is added, sufficient plasticity cannot be obtained, and at the same time, compatibility decreases, and bleeding becomes severe.

Preferable specific examples of the present ester include p
Butoxyethoxyethyl hydroxybenzoate, cyclohexyloxyethoxyethoxyethyl p-hydroxybenzoate, p-hydroxybenzoic acid (p-nonylphenoxyethyl) and the like.

As the polyamide according to the present invention, a polymer having an amide group in the molecular chain is generally used. Specifically, adipic acid, aminoundecanoic acid, aminocaproic acid, aminododecanoic acid, isophthalic acid, ε-caprolactam 3,3′-dimethyl-4,4′-diaminodicyclohexylmethane, sebacic acid, terephthalic acid,
Polymers starting from one or more of α, ω-dodecanoic acid, hexamethylenediamine and ω-laurolactam; mixtures of the above polymers; starting materials starting from adipic acid and 1,3-benzenedimethanamine And polymers starting from adipic acid, 1,3-benzenedimethanamine, and bis (aminopropyl) poly (ethylene oxide).

The above polyamide is, for example, nylon 6,
Nylon 66, nylon 610, nylon 11, nylon 12, and copolymerized nylon are commercially available. Among them, nylon 11 and nylon 12 are excellent in compatibility with the present ester.

The amount of the present ester used is appropriately selected according to its use, but is usually about 1 to 50 parts by weight, more preferably 5 to 30 parts by weight, per 100 parts by weight of the polyamide.
It is about weight. When the amount is less than 1 part by weight, a predetermined plasticizing effect is hardly obtained, and when the amount exceeds 50 parts by weight,
Bleeding on the resin surface is severe, which is not preferable in any case.

As a method for adding the present ester to the polyamide, a known method, for example, a method in which a desired amount thereof is mixed with a polyamide powder or pellet in a mixer at a temperature lower than the softening point of the polyamide and then extruded at a temperature higher than the softening point of the polyamide Alternatively, a method of adding and mixing into a monomer before polymerization or at a stage during polymerization can be used.

Further, the present ester can be used in combination with other known plasticizers, and if necessary, a coloring agent, a processing aid, a filler, a crosslinking agent, and the like, as long as a predetermined effect is not impaired.
You may mix with additives, such as an antioxidant or an antistatic agent.

The polyamide resin composition thus obtained is useful as a material for tubes and hoses for automobiles.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to the following examples.
You. The properties of the resin composition in each example were determined by the following method.
Was measured and evaluated. Mechanical properties : Based on ASTM D-638.

Cold resistance : Crashberg method (JIS K)
6745).

Compatibility : Pressed sheet of compounded resin
After leaving for 48 hours in a constant temperature and humidity room at 60 ° C. and 60% RH, the amount of bleeding of the plasticizer on the sheet surface was visually observed and evaluated according to the following criteria. ：: No bleed, Δ: Slight bleed, ×: Surface wet with plasticizer

Oil resistance : A press sheet obtained from a compounded resin is immersed in gasoline, and the ratio (% by weight) of the weight loss before and after immersion of the test piece when left in a constant temperature room at 25 ° C. for 48 hours is measured.

Example 1 100 parts by weight of nylon 12 (UBE Nylon 3030B, manufactured by Ube Industries, hereinafter the same) and 15 butoxyethyl p-hydroxybenzoate (hereinafter referred to as "product 1 of the present invention")
Prepare a polyamide resin composition by blending parts by weight,
The product was evaluated for mechanical properties, cold resistance, compatibility and oil resistance. Table 1 shows the obtained results.

Example 2 A polyamide resin composition was prepared by blending 100 parts by weight of "Nylon 12" and 15 parts by weight of cyclohexyloxyethoxyethoxyethyl p-hydroxybenzoate (hereinafter referred to as "product 2 of the present invention"). This was evaluated for mechanical properties, cold resistance, compatibility and oil resistance. Table 1 shows the obtained results.

Comparative Example 1 The mechanical properties, cold resistance, compatibility and oil resistance of "Nylon 12" itself were evaluated. Table 1 shows the obtained results.

Comparative Example 2 A polyamide resin composition was prepared by mixing 100 parts by weight of “Nylon 12” and 15 parts by weight of 2-ethylhexyl p-hydroxybenzoate (hereinafter abbreviated as “EHPB”). The mechanical properties, cold resistance, compatibility and oil resistance were evaluated. Table 1 shows the obtained results.

[Table 1]

[0027]

By blending the ester according to the present invention with polyamide, a polyamide resin composition having excellent plasticity, retention and cold resistance can be obtained.

──────────────────────────────────────────────────の Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 77/00-77/12 CA (STN)

Claims (1)

(57) [Claims] 1. A polyamide resin composition comprising a p-hydroxybenzoic acid ester represented by the general formula (1). Embedded image [In the formula, R represents an alkyl group, a cycloalkyl group which may have a substituent, an aryl group or an aralkyl group.
A represents an alkylene group having 2 to 4 carbon atoms. n is 1 to 20
Indicates an integer. ]