JP2002030148A - Polyamide resin composition and fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide resin composition of high degree of polymerization, excellent in strengths for an industrial fiber material. SOLUTION: This polyamide resin composition is prepared by solid polymerization of a Nylon 66 containing phosphorus, and has a relative viscosity of not less than 3.2 after solid polymerization, and the difference of the relative viscosities before and after the solid polymerization is not less than 0.9.

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 and a fiber obtained by spinning the same, and more particularly, to a high-strength polyamide resin composition for industrial material fibers useful for producing industrial material fibers. .

[0002]

2. Description of the Related Art Polyhexamethylene adipamide (hereinafter, referred to as polyhexamethylene adipamide)
Nylon 66) has high mechanical strength and excellent heat resistance, abrasion resistance, and chemical resistance, and is therefore widely used in applications such as fibers and plastics. Among them, fibers used for industrial applications are required to have particularly high strength. Generally, to obtain a high-strength polyamide fiber, a high degree of polymerization, that is, a nylon 66 resin having a high relative viscosity is required.However, to obtain a nylon 66 having a high degree of polymerization only from liquid-phase polymerization, It is difficult because there are problems such as ejection troubles due to foaming and excessive rise in viscosity. For this reason, it is common practice to perform liquid phase polymerization and once make pellets or powders, and then achieve the desired degree of polymerization by solid phase polymerization.

On the other hand, in order to efficiently increase the degree of polymerization, a phosphorus compound such as a phosphoric acid ester which promotes polymerization is often added as a catalyst. This phosphorus compound is generally added to the polymerization vessel together with the polymer material during the liquid phase polymerization,
The polymerization catalyst is effective for both liquid phase polymerization and solid phase polymerization. In addition, to contribute to the viscosity change even when performing melt spinning, in order to stably obtain a polymer of the desired degree of polymerization,
The amount of phosphorus compound added and its type must be carefully selected. For example, use of a specific phosphorus compound for polyamide in JP-A-4-370124 or phosphites containing an alkali metal hypophosphite as a main catalyst described in JP-A-7-82370. There have been many reports specifying the type of phosphorus compound as seen in catalysts for the production of polyamide polymers using a compound selected from amines and salts as cocatalysts.

[0004] However, such a phosphorus compound may have various effects on the degree of polymerization depending on the type and amount of the phosphorus compound, and may cause gelation. There is a problem that it is difficult to determine it and it is not possible to obtain a sufficient strength stably when it is used as an industrial fiber.

[0005]

SUMMARY OF THE INVENTION Accordingly, it is a main object of the present invention to provide a polyamide resin composition having a high degree of polymerization, which can solve such disadvantages and can be used for high-strength industrial material fibers. .

[0006]

According to the present invention, there is provided a composition comprising a phosphorus compound and nylon 66 as essential components.
The relative viscosity after solid-phase polymerization at 0 ° C. for 12 hours is at least 3.2 or more, and the difference between the relative viscosities before and after solid-state polymerization under the above conditions is 0.9 or more. The present invention provides a polyamide resin composition characterized in that:

[0007]

Embodiments of the present invention will be described below. According to experiments performed by the present inventors, phosphorus-containing nylon 6 must be used for industrial material fibers.
In the case of solid-state polymerization of No. 6, it was found that the relative viscosity after the solid-state polymerization was 3.2 or more, and the difference between the relative viscosities before and after the solid-state polymerization was 0.9 or more.

Here, the relative viscosity is defined as 9 at 25 ° C.
It refers to the relative viscosity when 1 g of a polymer is dissolved in 100 ml of 8% sulfuric acid. Here, the solid-phase polymerization means heating at 170 ° C. for 12 hours at a pressure of 40 Pa.

In the present invention, the inclusion of a phosphorus compound is essential. The phosphorus compound acts as a polymerization catalyst. This can be added at any time during melt polymerization,
Preferably, it is added simultaneously with hexamethylene diammonium adipate which is a raw material of nylon 66. The melt polymerization may be either a continuous type or a batch type. The phosphorus compound is not particularly limited, but preferably phosphoric acid, phosphorous acid, hypophosphorous acid, and salts or ester compounds thereof can be used. These phosphorus compounds can be used in combination of two or more.

In the present invention, under a pressure of 40 Pa, 170 ° C.
The relative viscosity after solid-phase polymerization is at least 3.2 or more when solid-state polymerization is carried out under the conditions of 12 hours, and the difference between the relative viscosities before and after solid-state polymerization under the above conditions is 0.9. It is important that this is the case. Relative viscosity after solid state polymerization is 3.2
If the difference between the lower viscosity and / or the relative viscosity before and after the solid phase polymerization is smaller than 0.9, the strength of the fiber obtained by melt-spinning the fiber is insufficient for industrial material fibers, which is not preferable.

The polyamide resin composition of the present invention may be prepared by adding a monocarboxylic acid or a monoamine to adjust the terminal of nylon 66 by a known method.

In addition, nylon 66 used for solid-state polymerization is
There is no problem if other copolymer compositions are present. As the copolymerization composition, for example, lactams such as ε-caprolactam, dicarboxylic acids such as terephthalic acid, diamines such as meta-xylylenediamine, dibasic acid salts composed of dicarboxylic acids and diamines such as hexamethyldiammonium isophthalate, and the like. No.

In addition, as long as the effects of the present invention are not impaired, there is no problem even if known additives such as a concealing agent, a heat-resistant agent, an antistatic material, a weathering agent plasticizer, and a pigment are added.

The polycondensation reaction of nylon 66 is usually carried out at 200
The reaction is carried out at a temperature in the range of 300 to 300 ° C., preferably 220 to 290 ° C., usually for 5 hours or less, preferably 3 hours or less, and more preferably 2.5 hours or less. A long polycondensation reaction time is not appropriate because it causes decomposition of the phosphorus compound.

The solid-state polymerization can be performed by either a continuous system or a batch system, and even under a vacuum condition of 700 Pa or less,
There is no problem even under the flow of an inert gas such as nitrogen. The temperature at the time of the solid phase polymerization may be any temperature below the melting point of nylon 66. However, in order to avoid problems such as fusion, it is desirable that the temperature be 200 ° C. or less, preferably 180 ° C. or less.

[0016]

The present invention will be described in more detail with reference to the following examples. The analysis and measurement described in Examples and Comparative Examples were performed according to the following methods. (1) Relative viscosity Using an Ostwald viscometer, 0.01 g / mL of 98
% Sulfuric acid solution / 25 ° C. relative viscosity was measured. (2) Thread strength Using a “Tensilon ULT-4L” type tensile tester (manufactured by Orientec Co., Ltd.), JISL-1017, 7.
5 measured.

Example 1 1,500 g of an 80% aqueous solution of hexamethylenediammonium adipate (AH salt)
And 0.54 g of phenylphosphonic acid as a phosphorus compound were charged into an autoclave having an internal volume of 5 L, and the internal pressure was 1.8 MPa.
Then, the temperature was raised to a, and this pressure was maintained until the internal temperature of the can reached 255 ° C., and then the pressure was released to atmospheric pressure over 1 hour. Thereafter, the pressure in the autoclave was reduced to 0.09 MPa, and the pressure was maintained after maintaining the reduced pressure for 5 minutes. Then, nylon 66 was discharged from the autoclave into a strand and formed into chips. The obtained chip is subjected to 170 Pa under a vacuum of 40 Pa.
After reacting for 12 hours under the condition of ° C. and performing solid phase polymerization,
The moisture was adjusted to a moisture content of 0.1%, melted at a polymer temperature of 290 ° C. using an extruder-type spinning machine, and spun through a 0.3 mmφ die hole. After the spun yarn was quenched and an oil agent was applied, it was hot-drawn at a total draw ratio of 5 times by two-stage drawing using a hot roller at 240 ° C. The relative viscosity of the obtained polymer before and after solid-state polymerization and the strength of the spun yarn were as shown in Table 1.

Comparative Example 1 The same operation as in Example 1 was performed by adding 0.10 g of red phosphorus as a phosphorus compound. Table 1 shows the results.

Comparative Example 2 The same operation as in Example 1 was performed without adding a phosphorus compound. Table 1 shows the results.

Comparative Example 3 Phenylphosphonic acid 0.54
g, and the same operation as in Example 1 was performed. However, the decompression time of the autoclave was 30 minutes, and the melt spinning was performed without performing the solid-phase polymerization. Table 1 shows the results.

[0021]

[Table 1]

As is clear from the results in Table 1, the fibers having a relative viscosity of not less than 3.2 after the solid-phase polymerization and a change of the relative viscosity before and after the solid-state polymerization of not less than 0.9 were obtained. Had sufficient strength.

[0023]

EFFECT OF THE INVENTION Nylon 66 obtained by the present invention
Fibers melt-spun using polymers exhibit excellent strength as fibers for industrial materials.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) D01F 6/60 351 D01F 6/60 351B F term (reference) 4J001 DA01 DB01 EB08 EC08 EE16D EE77D FA01 FB03 FC03 FD01 GA15 GB02 GB03 GB06 GB11 GB16 JA10 JB02 4J002 CL031 DH026 EW126 FD206 GK01 4L035 BB36 EE08 FF01 GG02 GG05 HH10 JJ25

Claims (3)

[Claims] 1. A composition containing a phosphorus compound and polyhexamethylene adipamide as essential components.
The relative viscosity after solid-phase polymerization is at least 3.2 or more when the solid-state polymerization is performed at 170 ° C. for 12 hours under the pressure described above, and the relative viscosity before and after the solid-state polymerization is performed under the above-described conditions. A difference of 0.9 or more. 2. The polyamide resin composition according to claim 1, which contains at least one phosphorus compound. 3. A fiber obtained by subjecting the polyamide resin composition according to claim 1 or 2 to solid state polymerization and then spinning.