JPH0592482A - Stretched molded article composed of polyamide composition - Google Patents

Abstract

PURPOSE:To obtain an oriented molded object of polyamide which is superior in resistance to impact, water absorption properties, friction/wear characteristics, and the like and useful in the application of a fiber, a tube, a pipe, a film, a blow, and the like. CONSTITUTION:A molded object in this invention is made of a composition containing 100 pts.wt. polyamide (A); 0.1-30 pts.wt. hydrocarbon polymer (B) having a number-average molecular weight of 500-50.000 and acide anhydride group as terminal group; 100-60 pts.wt. polymer (C) containing 0-60 pts.wt. polymer compatible in the component (B); and 0-40 pts.wt. inorganic filler (D).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention improves the dimensional change during water absorption, which is said to be a drawback of conventional polyamide-based products, in molded products such as films, fibers and pipes that are stretched and used.
In addition, the present invention relates to a molded product made of a polyamide composition that has been given functions such as impact resistance.

[0002]

2. Description of the Related Art Polyamides centering on nylon 6 and nylon 66 have been used for a long time in films and fibers as well as injection molded products. In addition to the inherent strengths of polyamide such as toughness, heat resistance, and oil resistance, various attempts have been made to give new characteristics by alloying and compounding.For example, combination with an elastomer may improve impact resistance. It is already well known in injection molded products. It can also be said that it is known that the water absorption is improved by the combination with polyolefin. However, with regard to application of such alloys to fibers, for example, PA / PPE systems (JP-A-2-104724) and PA / polyolefin systems (JP-A-3-51314) have been proposed, but comparatively few research examples have been proposed. ..

[0003]

The above-described alloying formulation, when used by drawing like a fiber, causes a drawback on the one hand. Firstly, the stretchability is extremely lowered, and secondly, it is difficult to maintain the balance of physical properties, specifically strength and rigidity. In addition, there are cases in which the appearance and physical properties vary depending on the part of the molded product, and deterioration of long-term characteristic data is caused. In this way, it is no exaggeration to say that it is extremely difficult to impart new properties while maintaining the original characteristics of polyamide in a molded product that involves a high degree of stretching.

[0004]

Means for Solving the Problems The inventors of the present invention have made various investigations in order to solve the above problems and find a polyamide composition having characteristics of physical properties. It has been found that it is possible to provide a stretched product having excellent stretchability, excellent abrasion resistance, abrasion resistance, and the like, and in which physical properties of flexibility and strength are balanced.

The stretched polyamide of the present invention comprises (A) 100 parts by weight of polyamide (B) a number average molecular weight of 500 to 50,000, and a hydrocarbon polymer having an acid anhydride group at the end of 0.1 to 30. Parts by weight (C) Polymer having compatibility with component (B) 0 to 60 parts by weight Polymer, 100 to 60 parts by weight (D) Inorganic filler 0 to 40 parts by weight

Polyamide as the component (A) is nylon 6, nylon 66, nylon 46, nylon 6/6.
6 copolymer, nylon 12, nylon 6/10, nylon 6T / 6, nylon 6T / 66, nylon 6T / 6I
A crystalline polyamide such as / 66 is used. 6T here
Represents hexamethylenediamine / terephthalic acid, and 6I represents hexamethylenedian / isophthalic acid. The polyamide used may be a simple substance, a copolymer, or a mixture of two or more kinds.

As the component (B), the polymer main chain is represented by the formula (1)

[0008]

[Chemical 1]

It mainly consists of units of (where R
Represents a substituent such as an alkyl group or a phenyl group), an acid anhydride group at the terminal, for example, a compound represented by the formula (2)

[0010]

[Chemical 2]

Having a number average molecular weight of 500 to 500
00. Specific examples of the compound include polybutadiene, a butadiene-styrene copolymer, polyisoprene or a polymer obtained by binding trimellitic acid to the terminal of a hydride thereof. As a method for producing these components, for example, a method utilizing a reaction between a terminal hydroxyl group and an acid anhydride group-containing acid chloride is known. A particularly preferred compound is hydrogenated polybutadiene which has trimellitic acid bound to the terminal.

The component (C) is a polymer having compatibility with the component (B), and examples thereof include polyethylene, polypropylene, ethylene propylene rubber, styrene butadiene block copolymer and hydrogenated styrene butadiene copolymer. . Further, these may be modified with a carboxyl group, an acid anhydride group or the like. When the polyamide component has a high melting point such as nylon 66, it is desirable that it has almost no unsaturated bond in the molecule, for example 1% or more, from the viewpoint of thermal stability. An inorganic filler such as talc, kaolin, silicon carbide, carbon black or zinc oxide is added to 100 to 60 parts by weight of the polymer composition comprising the components (A) to (C) for the purpose of imparting hardness and conductivity. 40
It is possible to mix in the range of less than or equal to parts by weight. Further, it does not matter at all to add glass fiber or carbon fiber within a range that does not impair the physical properties.

In addition, heat stabilizers, weathering agents,
Additives such as colored dyes and pigments can be added in a required amount. The components (A) to (D) are blended in a conventional kneading machine,
Alternatively, it is carried out by a method such as addition into the polymerization vessel. Furthermore,
Stretching of these compositions is carried out by previously molding the above composition part into filaments, films, pipes, other hollow bodies,
It is achieved by subjecting to a stretching process. The stretch ratio varies depending on the shape and the like, and is selected from 1.001 to 10 times, but the preferable stretch ratio is 1.2 to 6 times.

[0014]

EXAMPLES The present invention will be specifically described below with reference to examples.

[0015]

Example 1 Nylon 66 [ηr = 3.2 (JIS
K6810)] 100 parts by weight and trimellitic acid-modified hydrogenated polybutadiene (International Publication W O.89 / 081)
(20 compound synthesized by the method of Example 1) 3 parts by weight was kneaded and extruded by a twin-screw extruder to obtain pellets having moldability,
It was subjected to physical property measurement.

(A) Monofilament drawability: Spinning was carried out at a set temperature of 280 ° C. and a draw ratio of 4.0,
A good monofilament was obtained without yarn breakage. (B) Low water content (24 hours in water): 1.40%, which was lower than that of nylon 66 (Comparative Example 1) alone.

(C) Izod impact strength (ASTMD
256); 8.0 kgcm / cm (with notch),
It was better than nylon 66 alone. (D) Coefficient of friction (Cylindrical plane tester, weighted 10 kg /
cm ² ); 1.3 at a linear sliding velocity of 60 cm / sec.
0 was shown. (1.43 for nylon 66) (e) Chemical resistance; engine oil, antifreeze liquid (LLC liquid)
The immersion test was as good as nylon 66. Also,
The calcium chloride resistance and sodium hypochlorite resistance were superior to those of nylon 66 alone.

[0018]

Example 2 100 parts by weight of nylon 66 as a raw material,
An experiment was conducted in the same manner as in Example 1 except that 2 parts by weight of trimellitic acid-modified hydrogenated polybutadiene and 12 parts by weight of hydrogenated styrene butadiene block copolymer (molecular weight 50,000, 18% styrene) were used to obtain a composition pellet. It was
When the film-forming property of this product was examined with a small-sized film testing machine (setting temperature 290 ° C.), the thickness uniformity was good.
It was also confirmed that the splitting property was remarkably improved as compared with nylon 66 alone which was used as Comparative Experiment 1.

[0019]

Example 3 100 parts by weight of a composition of 100 parts by weight of nylon 66, 2 parts by weight of trimellitic acid-modified hydrogenated polybutadiene, and 12 parts by weight of hydrogenated styrene-butadiene block copolymer (molecular weight: 50,000, 18% styrene). ,
Extrusion was carried out in the same manner as in Example 1 except that 8 parts by weight of carbon black was additionally added to obtain black pellets. This product had an electric resistance of 10 ⁶ Ω on the surface of the molded product. IZOD impact strength (notched) is 5 kg · cm / c
It was m. On the other hand, the composition of 100 parts by weight of nylon 66 and 8 parts by weight of carbon black, which was used as Comparative Experiment 2, had an electric resistance of 10 ⁶ Ω, which was the same level, but an impact strength of 3.5 kg · cm / cm. It showed a low value. The monofilament obtained from this composition (stretching ratio: 1.5 times) showed a volume resistivity of 10 ⁴ Ω · cm. On the other hand, the volume resistivity of the monofilament of the composition used in Comparative Experiment 2 was 10 ⁶ Ω · cm.

[0020]

Example 4 A composition was prepared by using 20 parts by weight of silicon carbide instead of 8 parts by weight of carbon black in Example 3, and the composition was prepared in the same manner as in Example 1 using a monofilament (stretch ratio: 3.5 times). ) Got. This product showed good performance as an abrasive yarn.

[0021]

[Table 1]

[0022]

[Table 2]

[0023]

EFFECT OF THE INVENTION The polyamide composition using the component of the present invention has not only good stretchability but also strength of the stretched body,
Excellent flexibility, abrasion resistance and abrasion resistance. As a result, it is possible to use it under difficult environmental conditions, which has been difficult until now, and it can contribute to cost reduction of products. By using the composition of the present invention, a fibrous or film-like stretched product is obtained, and from these, it can be suitably used for fishing line, fish net, felt for paper making, abrasive paper, artificial grass, conductive yarn and the like. It is also suitable for pipes, tanks, bottles, tubes and the like.

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Claims (1)

[Claims] 1. (A) Polyamide 100
Parts by weight (B) Hydrocarbon-based polymer having a number average molecular weight of 500 to 50,000 and having an acid anhydride group at the end 0.1 to 30 parts by weight (C) Polymer compatible with component (B) A stretched molded product composed of a polymer of 0 to 60 parts by weight, 100 to 60 parts by weight (D) an inorganic filler of 0 to 40 parts by weight.