JP3033197B2 - Polyamide composition for non-fibrous molded article - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a plasticized polyamide
The present invention relates to a polyamide composition for a non -fibrous molded article, which gives long-term flexibility, heat resistance and weather resistance to the non-fibrous molded article. More particularly, the present invention is excellent in heat resistance without impairing the flexibility over a long period, it is Ru is required having excellent environmental resistance such as weather resistance, used tubing, hose, as industrial products such as sheet non Fibrous formed body
It relates use polyamides composition.

[0002]

2. Description of the Related Art A plasticized polyamide is generally produced by kneading a low molecular weight monomer with a polyamide (non-plasticized polyamide), and the amount of a plasticizer is kneaded in accordance with the degree of flexibility.

[0003] These plasticized polyamides have almost no problem when used in a normal atmosphere.
When exposed to a temperature atmosphere of 0 ° C. or higher, the plasticizer volatilizes from the plasticized polyamide, and the content of the plasticizer decreases over time.

[0004] That is, if the heating state is continued, the original flexibility of the plasticized polyamide is lost as the content of the plasticizer decreases, and this is a problem in long-term use.

[0005] Therefore, in order to maintain these long-lasting flexibility, plasticizers that do not volatilize from the plasticized polyamide have been studied, and high-molecular-weight type plasticizers have been proposed as such plasticizers.

[0006] However, plasticizers that are usually used include those intended for imparting flexibility rather than suppressing volatilization,
Specifically, a low molecular weight liquid monomer having a large plasticizing effect is generally used.

On the other hand, as a stabilizing prescription of polyamide,
It is known to mix cuprous iodide and an alkali metal iodide (Japanese Patent Publication No. 37-14630).

[0008]

However, in the field of plasticized polyamides, it is almost impossible to maintain the flexibility of plasticized polyamides containing a low-molecular-weight plasticizer over a long period of time.

On the other hand, polyamides have poor environmental resistance properties such as heat resistance and weather resistance, and plasticized polyamides imparted with flexibility also have poor environmental resistance properties.

However, at present, there are few studies on stabilizing prescriptions for plasticized polyamides such as heat resistance and weather resistance, and the stabilizing prescriptions for polyamides which are usually used are simply applied. Also have the following problems.

The following stabilizers for polyamides and weathering agents are widely used as stabilizers for plasticized polyamides. For example, to improve heat resistance, hindered phenol-based stabilizers and aromatic amine-based stabilizers,
In order to improve the weather resistance, there are hindered amine stabilizers and the like. In order to further improve heat resistance and weather resistance, the formulation is a combination of an aromatic amine-based stabilizer and a hindered amine-based stabilizer.

However, when these stabilizing formulations are applied to a plasticized polyamide, there is a difference in the compatibility between the stabilizer, the plasticizer and the polyamide, compared to the case where the stabilizer and the plasticizer are individually compounded in the polyamide. Behavior.

That is, since the hindered phenol-based stabilizer and the aromatic amine-based stabilizer as described above are more compatible with the plasticizer than with the polyamide,
There is a problem that the stabilizer volatilizes with the volatilization of the plasticizer, and when used for a long period of time, flexibility, heat resistance and weather resistance are impaired.

Accordingly, an object of the present invention is to provide a polyamide composition which is excellent in heat resistance and weather resistance for a long time without impairing flexibility.

[0015]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have reached the present invention.

That is, the present invention relates to (A) nylon 11
Or p-oxybenzoic acid esterification to nylon 12
Compound, aromatic oxycarboxylic acid ether compound, pheno
Compounds, aromatic oxyaldehyde compounds, polyvalent
Nol phosphate compound, N-alkylbenzenesulfur
Honamide compound, N-alkyl-p-toluenesulfo
Group of amide compounds and p-toluenesulfonamide
100 parts by weight of a plasticized polyamide containing 5 to 25% by weight of a low molecular weight plasticizer selected from the group consisting of 0.005 to 0.1 parts by weight of (B) a copper halide compound in terms of copper atomic weight; (C) A polyamide composition for a non-fibrous molded article, which comprises 0.05 to 1 part by weight of potassium halide.
Here, the non-fibrous molding is a tube, hose or sheet.
It is represented by being.

In the present invention, it is important to use copper halide in combination with potassium halide, and the effect becomes more remarkable by using copper halide as a complex with a specific compound. is there.

In the present invention, by employing the above constitution, volatilization of the plasticizer and the stabilizer is suppressed, and good flexibility, heat resistance and weather resistance are maintained over a long period of time.

Hereinafter, the present invention will be described in detail.

The (A) plasticized polyamide in the present invention is a nylon 1 obtained from 11-aminoundecanoic acid.
Nylon 12 obtained from 1, or 12-aminododecanoic acid or laurolactam has a low molecular weight plasticizer 5
25% by weight is blended.

The low molecular weight plasticizer is a plasticizer which, when incorporated into a polyamide containing no other additives, is volatilized from the polyamide when exposed to an atmosphere at a temperature of 100 ° C. or higher, and comprises p-oxybenzoic acid. Ester compounds, aromatic oxycarboxylic acid ether compounds, phenol compounds,
Aromatic oxyaldehyde compound, polyhydric phenol phosphate compound, N-alkylbenzenesulfonamide compound, N-alkyl-p-toluenesulfonamide compound
Objects and p - Low selected from the group consisting of toluenesulphonic ami de
It is a molecular weight plasticizer. Among them, N-butylbenzenesulfonamide of N-alkylbenzenesulfonamide compound, N-ethyl-p-toluenesulfonamide of N-alkyl-p-toluenesulfonamide compound and p-
Toluenesulfonamide is preferably used.

The (B) copper halide compound in the present invention includes copper (I) (II) iodide, copper (II) chloride (II), copper (II) acetate, and the like. Cuprous iodide is preferably mentioned.

In the present invention, when the above-mentioned copper halide compound is used as a complex of a copper halide and a compound selected from 2-mercaptobenzimidazole and 2-mercaptobenzthiazole, the effect of the present invention is further enhanced. Can be improved. In the above complex, the compound to be reacted with the copper halide is 2-mercaptobenzimidazole or 2-mercaptobenzthiazole, with 2-mercaptobenzimidazole being preferred.

The above-mentioned complex is usually combined with a copper halide,
It is a complex with a compound selected from 1 to 2 moles, preferably equimolar, of 2-mercaptobenzimidazole and 2-mercaptobenzthiazole.

In the present invention, a complex salt of cuprous iodide and equimolar 2-mercaptobenzimidazole is most preferably used.

The amount of the copper halide to be added is 0.005 to 0.005 in terms of copper atoms per 100 parts by weight of the plasticized polyamide.
0.1 parts by weight. When the addition amount is less than 0.005 parts by weight, the heat resistance of the obtained composition is not sufficient, and
Even if it exceeds 1 part by weight, the heat resistance and weather resistance of the obtained composition are not significantly changed and are not economical.

As the potassium halide (C) in the present invention, potassium chloride, potassium iodide and the like can be mentioned, among which potassium iodide is preferably used.

The amount of the potassium halide to be added is 0.05 to 1.0 part by weight, preferably 0.1 to 0.5 part by weight, based on 100 parts by weight of the plasticized polyamide.

When the addition amount of potassium halide is less than 0.05 part by weight, the heat resistance and weather resistance of the obtained polyamide composition are reduced, and the polyamide obtained even when the addition amount exceeds 1.0 part by weight is obtained. The heat resistance and weather resistance of the composition are not significantly changed and are not economical.

The method for producing the polyamide composition of the present invention is not particularly limited, but it is preferable to dry blend copper (B) halide and potassium halide (C) with the plasticized polyamide before molding.

The polyamide composition of the present invention can be generally formed into various molded articles by a known molding method.

[0032]

Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

The properties in the examples were determined as follows.

Heat resistance: A polyamide composition is formed into a sheet having a thickness of 2 mm by a hot press, and a dumbbell test piece according to JIS K6301 is punched out, and the test piece is treated in a hot air oven at a predetermined temperature and time. Was measured for tensile strength and elongation using a tensile tester “Tensilon” 100 (manufactured by Shimadzu Corporation). Then, the tensile elongation after the heat treatment with respect to the tensile elongation measured before the heat treatment was calculated as a tensile elongation retention [tensile elongation retention = (tensile elongation after heat treatment / tensile elongation before heat treatment) × 100 (%)]. As a measure of heat resistance, the half-life at that temperature was set at 50% tensile elongation retention.

Weather resistance: Using a test piece similar to the one used for measuring heat resistance, a weather O-meter (manufactured by Suga Test Machine) was used for 200 hours and 500 hours (both at 63 ° C.
Water was sprayed for 18 minutes during 2 hours). Tensile strength and elongation were measured using "Tensilon" 100 after irradiation with light by a carbon arc. Then, similarly to the case of heat resistance, the tensile elongation after the weather resistance test with respect to the tensile elongation measured before the weather resistance test was calculated as a tensile elongation retention. As a measure of weather resistance, the half-life was defined as a tensile elongation retention of 50%.

Plasticizer weight loss rate: Using a test piece similar to that used for measuring heat resistance, in a hot air oven at 120 ° C.
The weight loss of the sample treated for 500 hours was measured, and the ratio to the amount of the plasticizer added was calculated.

Examples 1-2, Comparative Examples 1-8 Thermoplastic polyamide (trade name "Rilsan" BESNO ATO C
hem., nylon 11) or plasticized polyamide (trade name "Rilsan" manufactured by BESNO P40 ATO Chem.), plasticized nylon-11, low molecular weight plasticizer (N-butylbenzene sulfone)
Honamide) (containing about 14% by weight) as a hindered phenol-based stabilizer in the pellets "Irganox
x) "1098," Naugard as an aromatic amine stabilizer
(Naugard) "445", "Tinuvin" 326 as a hindered amine stabilizer, copper iodide, potassium iodide and "OS-13" (equimolar complex of copper iodide and 2-mercaptobenzimidazole). Dry blending was performed immediately before extrusion at the ratio described in 1 and kneaded using a 30 mmφ extruder (Dalmage Screw, manufactured by Tanabe Seisakusho) at 250 ° C. The gut was cooled in a water bath, passed through a cutter, and pelletized.

The pellets were placed in a hot air oven at 70 ° C. for 1 hour.
Dry for 5 hours. The dried pellets were melted by hot pressing to produce a 2 mm-thick pressed sheet. The heat resistance aging test was performed at three levels of 120 ° C, 140 ° C, and 150 ° C.

Table 1 shows the results of heat aging resistance.

[0040]

[Table 1]

The following is clear from the results in Table 1.

That is, in a normal polyamide,
There is no significant difference in the heat resistance effect when any of the hindered phenol stabilizer, the aromatic amine stabilizer, the hindered amine stabilizer and the copper halide-potassium halide stabilizer is used. However, the heat resistance of a plasticized polyamide is very good only when a copper halide-potassium halide stabilizer is used.

Examples 3 to 4 and Comparative Examples 9 to 11 A weather resistance test was performed using the 2 mm-thick press sheet prepared in Example 1. Table 2 shows the results.

[0044]

[Table 2]

From the results shown in Table 2, it is clear that the weather resistance of the copper halide stabilizer is very good.

Examples 5 to 6, Comparative Examples 12 to 14
The plasticizer weight loss rate was measured using the 2 mm-thick press sheet prepared in the above. At this time, the flexural modulus was measured using the dumbbell which had been measured. Table 3 shows the results of the plasticizer weight loss and flexural modulus at that time.

[0047]

[Table 3]

From the results shown in Table 3, it can be seen that when a copper halide-based stabilizer was used, the plasticizer weight loss rate was extremely low, and the volatilization of the plasticizer was suppressed. Furthermore, when a copper halide-based stabilizer is used, it is apparent that the flexibility is maintained with little increase in flexural modulus due to heat treatment.

[0049]

Industrial Applicability The polyamide composition of the present invention is excellent in heat resistance and weather resistance without impairing flexibility over a long period of time.

The polyamide composition of the present invention is particularly suitable for hoses, tubes, sheets, industrial parts, etc. in the field where flexibility is required for a long period of time and excellent in heat resistance and weather resistance are required. Can be suitably used.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI C08K 3:16 5:00)

Claims (2)

(57) [Claims] (A) Nylon 11 or nylon 12
A p-oxybenzoate compound, an aromatic oxy
Carboxylic acid ether compounds, phenol compounds, aromatic
Oxyaldehyde compound, polyhydric phenol phosphate
Compound, N-alkylbenzenesulfonamide compound,
An N-alkyl-p-toluenesulfonamide compound; and
Low molecular weight selected from the group of p-toluenesulfonamide
Plasticized polyamide 1 containing 5 to 25% by weight of a plasticizer
00 parts by weight, (B) the copper halide compound is 0.00
5 to 0.1 parts by weight of (C) a non-fibrous molded body Polyamide composition obtained by blending potassium halide 0.05-1 parts by weight. 2. The non-fibrous formed article is a tube, a hose or
2. The polymer for a non-fibrous formed article according to claim 1, wherein the sheet is a sheet.
Mid composition.