JP2006176656A - Polyamide resin and monofilament - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a new copolymer polyamide resin, particularly an excellent polyamide resin exhibiting a significantly high strength when formed to a monofilament such as a fishing line, and to provide a monofilament made from the same. <P>SOLUTION: The polyamide resin comprises a 6-aminocaproic acid unit, an aromatic dicarboxylic acid unit, an aliphatic dicarboxylic acid unit and a diamine unit, as constituents thereof. The sum of the content of the aliphatic dicarboxylic acid unit and the diamine unit is greater than the content of the 6-aminocaproic acid unit. The polyamide resin has a melting point as measured by a differential scanning calorimeter of 180-250°C. In the measurement, the resin was cooled from a molten state to 30°C at a temperature decreasing rate of 20°C/min and then heated at a temperature increasing rate of 20°C/min. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a novel copolymerized polyamide resin. Specifically, the present invention relates to an excellent polyamide resin that exhibits remarkably high strength when used as a monofilament such as a fishing line, and a monofilament comprising the same.

  Polyamide resins are frequently used as monofilaments for fishing lines, fish nets, guts, etc., due to their high strength. Specifically, there is a demand for a monofilament with high strength that can maintain a high load resistance even if the line diameter is reduced so as not to give a sense of alertness to fish, that is, the presence of a fishing line. For fishing line and fish net use, in addition to the strength of monofilament, characteristics such as high transparency and flexibility are required.

  For such purposes, polycapramide (polyamide 6) made from caprolactam as a raw material has been often used. However, other than that, polyamide 6/66 copolymerized with caprolactam, adipic acid and hexamethylenediamine, or polyamide A pellet blend of 6 and polyamide 6/66 has been suitably used.

  For example, polyamide 6/66 has been proposed as a raw material polyamide for obtaining monofilaments having excellent transparency, tensile strength, and knot strength (see, for example, Patent Document 1). In order to improve the flexibility and strength of thick polyamide monofilaments, polyamide 6/66 / 6T, which is a three-component copolymer polyamide using hexamethylene diammonium terephthalate, is used as the main component. It has been proposed to use (see, for example, Patent Document 2).

  In addition, it has been proposed that a polyamide 6 / 6T copolymer (a copolymer of caprolactam and hexamethylene diammonium terephthalate) is a raw material for monofilaments with extremely excellent strength (see, for example, Patent Document 3). ). Furthermore, in order to improve the transparency, roundness, and flexibility of monofilaments, a polyamide resin obtained by copolymerizing caprolactam, hexamethylene diammonium salt, and alicyclic diamine / dicarboxylate has been proposed. (For example, see Patent Document 4).

JP 61-194215 A JP-A 63-235524 JP-A-2-268630 JP-A-6-299415

  As a general index of the strength of a monofilament, for example, g / d (gram / denier; strength per fiber degree obtained by dividing a breaking load by denier which is a weight of a single yarn of 9000 m), cN / unit of SI unit system dtex (centinewton / decitex; strength per fiber obtained by dividing the breaking load by decitex, which is the weight of a single yarn of 10,000 m) has been used conventionally. However, in such a notation method of strength by strength per fiber degree, there is a problem that even when the monofilament has the same breaking load and diameter, the numerical value indicating the strength is different when the specific gravity is different.

  Therefore, in recent years, the strength at the same diameter has been objectively described by using Pa (Pascal), which is a stress notation of SI indicating the strength per cross-sectional area. However, the polyamide resins proposed so far have not been satisfactory in terms of tensile strength and knot strength when monofilaments are used. Specifically, monofilaments with a tensile strength exceeding 1.2 GPa and a knot strength exceeding 1.1 GPa have not been obtained, and there are those that simultaneously satisfy sufficient transparency and flexibility when used as a fishing line. It was not obtained.

  The present inventors have intensively studied a polyamide resin which is excellent in both tensile strength and knot strength, which are various properties required for monofilaments, particularly monofilaments for fishing lines, and which satisfies both transparency and flexibility. As a result, as a constituent component of the polyamide resin, it contains a 6-aminocaproic acid unit, an aromatic dicarboxylic acid unit, an aliphatic dicarboxylic acid unit, and a diamine unit, and the total content of the aliphatic dicarboxylic acid unit and the diamine unit is When a terpolymer polyamide resin having a specific melting point of 180 ° C. or more and 250 ° C. or less, which is a ternary polyamide having a content higher than the content of 6-aminocaproic acid units, is a monofilament, a conventional polyamide monofilament As a result, it was found that strength, transparency, and flexibility were improved at the same time, and the present invention was completed.

  That is, the gist of the present invention includes a 6-aminocaproic acid unit, an aromatic dicarboxylic acid unit, an aliphatic dicarboxylic acid unit, and a diamine unit as a constituent component of the polyamide resin, and the total content of the aliphatic dicarboxylic acid unit and the diamine unit. Is higher than the content of 6-aminocaproic acid unit, and after using a differential scanning calorimeter, the temperature is lowered from the molten state to 30 ° C. at a temperature lowering rate of 20 ° C./min, and then at a temperature rising rate of 20 ° C./min. The present invention resides in a polyamide resin having a melting point of 180 ° C. or higher and 250 ° C. or lower when the temperature is raised.

  Another gist of the present invention resides in a monofilament having a diameter of 0.005 to 0.5 mm made of the polyamide resin.

  Moreover, the other summary of this invention exists in the fishing line which consists of said monofilament.

  Another gist of the present invention is that polycondensation is carried out in the same reaction system using ε-caprolactam, a diamine containing an aliphatic diamine as a main component, an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid as a polycondensation raw material. It exists in the manufacturing method of the said polyamide resin characterized by doing.

  The monofilament made of the polyamide resin provided by the present invention is excellent in mechanical strength such as linear strength and knot strength, and is excellent in transparency and flexibility. Therefore, it can be expected to exhibit excellent performance especially for fishing lines, fish nets and guts.

Hereinafter, the present invention will be described in detail.
The polyamide resin of the present invention is composed of a 6-aminocaproic acid unit, an aromatic dicarboxylic acid unit, an aliphatic carboxylic acid unit, and a diamine unit when its constituent components are expressed in monomer units. Furthermore, when expressed in terms of polyamide units after polycondensation, (1) an aliphatic polyamide unit (hereinafter sometimes referred to as the first component) and (2) a 6-aminocaproic acid unit (hereinafter referred to as the second component). And (3) an aromatic polyamide unit (hereinafter sometimes referred to as a third component).

  The aliphatic polyamide unit which is the first component in the present invention refers to a unit composed of a condensate of a diamine unit and an aliphatic dicarboxylic acid unit. Examples of the diamine include ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10 -Diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,13-diaminotridecane, 1,14-diaminotetradecane, 1,15-diaminopentadecane, 1,16-diaminohexadecane, 1,17 -Aliphatic diamines such as diaminoheptadecane, 1,18-diaminooctadecane, 1,19-diaminononadecane, 1,20-diaminoeicosane, 2-methyl-1,5-diaminopentane, cyclohexanediamine, bis- ( 4-aminohexyl) alicyclic diamines such as methane, xy And aromatic diamines such as phenylenediamine and the like. Of these, aliphatic diamines are preferable, and 1,6-hexamethylenediamine is particularly preferable. Moreover, when mixing and using various diamine, it is preferable that content of aliphatic diamine shall be 70 to 100 weight% in all the diamines.

  Examples of the aliphatic dicarboxylic acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, brassic acid, tetradecane. Diacid, pentadecanedioic acid, octadecanedioic acid and the like are used. Of these, adipic acid is preferred. In particular, a combination of 1,6-hexamethylenediamine and adipic acid (polyamide 66) is preferable.

  The first component is calculated as the total amount of the aliphatic dicarboxylic acid unit and the diamine unit condensed with the aliphatic dicarboxylic acid unit. The content is usually 60 to 94% by weight in the total polyamide resin. If it exceeds 94% by weight, the transparency and flexibility of the melt-spun monofilament are lowered, which is not preferable. If the amount is less than 60 parts by weight, the knot strength is reduced, which is not preferable. More preferably, it is 70 to 90 weight%, More preferably, it is 75 to 85 weight%.

In addition, content of an aliphatic dicarboxylic acid unit, an aromatic dicarboxylic acid unit, a diamine unit, and a 6-aminocaproic acid unit can be derived from the production conditions (feed composition of raw materials) of the polyamide resin. In the case of a polyamide whose production conditions are unknown, the polyamide is hydrolyzed into units (monomer units) of each component, followed by liquid chromatography (LC), gas chromatography (GC), mass spectrometry (MS) , Nuclear magnetic resonance analysis ( ¹³ C-NMR, H-NMR) and the like can be combined appropriately.

  For example, 0.1 g of a polyamide resin as a sample and 10 ml of 6N hydrochloric acid are charged in a glass tube, and after sealing the glass tube, the polyamide resin is hydrolyzed by holding at 160 ° C. for 10 hours. Next, a 25 wt% sodium hydroxide solution is added to the obtained treatment solution until neutrality, and the pretreatment solution is adjusted to a total volume of 25 ml with pure water. The pretreatment liquid is quantitatively analyzed by LC-MS and GC-MS.

  The 6-aminocaproic acid unit which is the second component in the present invention refers to a unit composed of a polymer of 6-aminocaproic acid and / or ε-caprolactam. The content of the second component is usually 5 to 35% by weight in the total polyamide resin. If it is less than 5% by weight, the flexibility of the monofilament is lowered, which is not preferable. On the other hand, if it exceeds 35% by weight, the knot strength is lowered, which is not preferable. Preferably it is 8-30 weight%, More preferably, it is 10-25 weight%.

  The aromatic polyamide unit as the third component in the present invention refers to a unit composed of a condensate of a diamine unit and an aromatic dicarboxylic acid unit. As diamine, it is the same as that used in order to form the aliphatic polyamide unit which is a 1st component. On the other hand, as the aromatic dicarboxylic acid, phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid and the like are used. Of these, terephthalic acid is preferred. In particular, a combination of 1,6-hexamethylenediamine and terephthalic acid (polyamide 6T) is preferable.

  The third component is calculated as the total amount of the aromatic dicarboxylic acid unit and the diamine unit condensed with the aromatic dicarboxylic acid unit. The content is usually 1 to 30% by weight in the total polyamide resin. If the amount is less than 1 part by weight, the flexibility and transparency are lowered, which is not preferable. If it exceeds 30% by weight, the properties of the knot strength of the monofilament are lowered, which is not preferable. Preferably it is 1 to 25 weight%, More preferably, it is 2 to 20 weight%.

  The polyamide resin of the present invention preferably has a melting point of 180 ° C. or higher and 250 ° C. or lower. If the melting point is too high, the transparency and flexibility of the melt-spun monofilament may be reduced. Conversely, if the melting point is too low, the knot strength may be reduced. The melting point of the polyamide resin of the present invention is preferably 185 ° C. or higher, more preferably 190 ° C. or higher, preferably 245 ° C. or lower, and more preferably 240 ° C. or lower. The melting point of polyamide referred to in the present invention means that the temperature was lowered from a molten state to 30 ° C. at a temperature lowering rate of 20 ° C./min using a differential scanning calorimeter, and then heated at a temperature rising rate of 20 ° C./min. It is defined as the melting peak temperature observed in some cases.

  In the present invention, the production method of the copolymerized polyamide resin is not particularly limited, and a conventionally known production method of polyamide can be applied. For example, a copolyamide can be produced by repeating normal pressure, reduced pressure, and pressurization operations as necessary by a batch or continuous polymerization method. Specifically, for example, a predetermined amount of an aqueous solution serving as a polycondensation reaction raw material is charged in the same reaction vessel, and a monocarboxylic acid such as acetic acid or benzoic acid, stearylamine, dodecylamine or the like as a molecular weight regulator as necessary. In addition, a monoamine etc. can be added, and furthermore, a heat stabilizer, a weather stabilizer, a polymerization accelerator and the like can be added.

  The diamines and dicarboxylic acids may be supplied to the reaction vessel alone, respectively, but after both are reacted in advance to form an equimolar salt (diammonium salt), the salt is supplied to the reaction vessel. Is preferred. For example, an equimolar salt of hexamethylenediamine and adipic acid (AH salt or 66 salt), an equimolar salt of hexamethylenediamine and terephthalic acid (6T salt), and the like can be used. It is also possible to use a method in which an aqueous solution of these aqueous solutions and a predetermined amount of ε-caprolactam is heated to a range where no precipitation of solids occurs and water is distilled to perform polycondensation. In either case, after the inside of the reaction vessel is replaced with nitrogen gas, the polymerization is carried out at a predetermined temperature and for a predetermined time while being heated under stirring and partially releasing the internal pressure. Thereafter, the internal pressure is reduced to atmospheric pressure, and further heated under a reduced pressure for a certain time to reach a desired polymer viscosity, and then discharged from the polymerization reaction vessel into water through a die. This is cut into chips, and the unreacted monomer is extracted and removed using boiling water. Thereafter, it is dried and obtained as a multi-component copolymer polyamide.

  In carrying out the polycondensation reaction, it is preferable to carry out the reaction by supplying all reaction raw materials into the same reaction system. In some cases, one or more of the raw materials can be concentrated or prepolymerized in one system, and polycondensation can be performed by adding the raw material aqueous solution in another system. Also, one or more of the raw materials are concentrated or prepolymerized in one system, and similarly concentrated or prepolymerized in one or more other systems, and these concentrated or prepolymerized. It is also possible to perform polycondensation after mixing two or more of the cakes.

  The degree of polymerization of the copolymerized polyamide resin of the present invention is not particularly limited, and the relative viscosity at 25 ° C. of a 98% sulfuric acid solution of 0.01 g / ml is usually 1.5 to 8.0, preferably 2.0. -5.0. If the relative viscosity is less than 1.5, the practical strength is insufficient, and if it is 8.0 or more, the melt fluidity is lowered and the molding processability is impaired.

  If necessary, the copolymerized polyamide resin of the present invention can be subjected to an extraction treatment using an alcohol solvent, hot water or the like for the purpose of removing a low molecular weight product, a polymerization accelerator or the like. Moreover, the polyamide resin obtained by this invention can be suitably dried with a vacuum dryer and a ventilation drier at an arbitrary stage by a known method.

  Furthermore, the polyamide resin of the present invention can be copolymerized with other components in an amount of less than 30% by weight, preferably less than 10% by weight, among components, and in an amount that does not impair the effects of the present invention.

  Typical copolymerization components include amino acids such as 11-aminoundecanoic acid, 12-aminododecanoic acid, paraaminomethylbenzoic acid, lactams such as ω-laurolactam, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexane. And alicyclic dicarboxylic acids such as dicarboxylic acids.

  In the present invention, in order to use the copolymerized polyamide resin for a monofilament, a method of appropriately stretching an undrawn yarn is employed. For example, in a heating atmosphere, stretching and heat setting are performed in two or three stages in the axial direction. The undrawn yarn can be extruded and cooled from a spinning nozzle using an extruder according to a conventional method. By adjusting the thickness of the unstretched filament, the thickness of the fishing line is adjusted to 0.005 to 0.5 mm, preferably 0.01 to 0.2 mm. Also, a so-called tapered line in which the thickness is continuously changed in the length direction can be used.

  An example of a three-stage drawing method known by the present inventors is that in the first stage drawing, the undrawn yarn is drawn 3 to 5 times, preferably 3.2 to 4 times. This stretching is performed in hot air, hot water, or a heating medium such as steam, but is preferably performed in a steam atmosphere at 90 to 105 ° C. The second stage stretching may be performed by a normal method, but the heating atmosphere is constituted by hot air, and stretching is performed at a temperature of 120 to 250 ° C. by 1.05 to 2.0 times. The heat setting is carried out in the third stage, but at a temperature of 140 to 250 ° C. while relaxing 0 to 10%. The total draw ratio is usually 4.5 to 7.0 times, preferably 5.0 to 6.5 times.

  When cooling the unstretched yarn with water, if a known additive, for example, a bisamide compound is added to 0.05 to 0.5 parts by weight of the copolymer polyamide, the stretching operation can be easily performed. It is preferable because the strength is increased. Usable bisamide compounds include N, N′-ethylenebisstearic acid amide, N, N′-methylenebisstearic acid amide, N, N′-xylylene bisstearic acid amide, N, N′-dioctadecyl terephthalate. A typical example is acid amide.

  In addition to bisamide, the copolymer polyamide used in the present invention may contain other additives such as lubricants, heat stabilizers, weathering agents, plasticizers, colorants, dyes and the like. Other components, such as antioxidants and heat stabilizers (hindered phenols, hydroquinones, phosphites and their substitutes, copper halides, iodine compounds, etc.), weathering agents (resorcinols), as long as the effect is not impaired , Salicylates, benzotriazoles, benzophenones, hindered amines, etc.), mold release agents and lubricants (fatty alcohols, aliphatic amides, aliphatic bisamides, bisureas, polyethylene waxes, etc.), pigments (cadmium sulfide, phthalocyanine, carbon) Black), dyes (nigrosine, aniline black, etc.), crystal nucleating agents (talc, silica, kaolin, clay, etc.), plasticizers (octyl p-oxybenzoate, N-butylbenzenesulfonamide, etc.), antistatic agents ( Alkyl sulfate type anionic antistatic agent, quaternary Nickel salt type cationic antistatic agents, nonionic antistatic agents such as polyoxyethylene sorbitan monostearate, betaine amphoteric antistatic agents, etc.), flame retardants (melamine cyanurate, magnesium hydroxide, aluminum hydroxide, etc.) Hydroxide, ammonium polyphosphate, brominated polystyrene, brominated polyphenylene oxide, brominated polycarbonate, brominated epoxy resins or combinations of these brominated flame retardants with antimony trioxide, etc., fillers (graphite, barium sulfate) , Magnesium sulfate, calcium carbonate, magnesium carbonate, antimony oxide, titanium oxide, aluminum oxide, zinc oxide, iron oxide, zinc sulfide, zinc, lead, nickel, aluminum, copper, iron, stainless steel, glass fiber, carbon fiber, aramid fiber , Bentonite Particulates such as montmorillonite, synthetic mica, fibrous, needle-like, plate-like filler), other polymers (other polyamides, polyethylene, polypropylene, polyester, polycarbonate, polyphenylene ether, polyphenylene sulfide, liquid crystal polymer, polysulfone, poly Ether sulfone, ABS resin, SAN resin, polystyrene, etc.) can be added at any time.

  In addition, when using polyamide monofilament for fishing lines, the surface of fishing lines can be used for winding on reels by applying known ingredients such as polyoxyethylene fatty acid esters and silicon emulsions on the surface. It is also possible to prevent the occurrence of scratches.

  In addition, the copolymerized polyamide of the present invention can be formed into a desired shape by an arbitrary forming method such as film forming, and can also be used as a film for fibers such as clothing and industrial materials, packaging and magnetic recording.

  In addition to the fishing line, the polyamide resin of the present invention can be used for pile yarn, base fabric, etc., which is a constituent layer of carpet by spinning a continuous bulky yarn (BCF), multifilament or non-woven fabric. . Furthermore, if necessary, a crystal nucleating agent (talc, silica, kaolin, clay, etc.) can be added to increase the rigidity of the filament. When coloring the BCF for pile yarn and the multifilament for the base fabric, the nylon resin and the dispersion colorant may be mixed in advance and colored or dyed. The pile yarn is planted on the base fabric by a conventional method such as tufted or hook. The copolymerized polyamide resin of the present invention is also suitably used as a mat yarn, a domestic carpet, an office carpet, an automobile carpet, and a yarn for clothing.

  Examples Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the description of these examples.

The following methods were used for measuring physical properties of polyamide, quantifying structural units, and evaluating monofilaments.
1. Relative viscosity (ηr):
Measurement was performed using an Ostwald viscometer at a concentration of 0.01 g / ml in 25% sulfuric acid in 98% sulfuric acid.
2. Melting point:
Using a differential scanning calorimeter, the melting peak temperature was determined when the temperature was lowered from the molten state to 30 ° C. at a temperature lowering rate of 20 ° C./min and then heated at a temperature rising rate of 20 ° C./min.
3. Linear Strength and Nodule Strength According to JIS L1013, dry linear strength and dry nodule strength were measured. The units of fineness and strength are indicated by GPa which is a stress unit of SI.

4). Polyamide constitutional unit content <Pretreatment>
After 0.1 g of polyamide resin and 10 ml of 6N hydrochloric acid were charged in a glass tube ampule and sealed, the polyamide resin was hydrolyzed by maintaining at 160 ° C. for 10 hours. Next, a 25% by weight sodium hydroxide aqueous solution was added to the obtained treatment liquid, and then a liquid whose total amount was made 25 ml with charged pure water was used as a pretreatment liquid.
<Quantification of 6-aminocaproic acid>
The prepared pretreatment liquid was measured by HPLC.

Apparatus: Shimadzu LC-10A
Column: Shiseido Capsule Pack C18 MG S-3 3μm 4.6mm x 75m
Detector: UV205nm
Mobile phase: 15% acetonitrile aqueous solution (0.01M octanesulfonic acid)
<Quantitative determination of terephthalic acid and adipic acid>
The prepared pretreatment liquid was measured by HPLC.

Apparatus: Shimadzu LC-10A
Column: Shiseido Capsule Pack C18 MG S-3 3μm 4.6mm x 75m
Detector: UV240nm
Mobile phase: 15% acetonitrile aqueous solution (0.01M octanesulfonic acid)
<Quantitative determination of hexamethylenediamine>
Bistrimethylsilylacetamide (5 ml), acetonitrile (5 ml) and triethylamine (1 ml) were added to the sample obtained by drying the above pretreatment liquid at 70 ° C. under reduced pressure, and trimethylsilylation treatment was performed at 70 ° C. for 10 minutes. The sample was then measured by GC / MS.

Device: JEOL JMS-700
Column: DB-1 1.0 μm 0.32 mm × 30 m
Column initial temperature: 120 ° C., heating rate: 10 ° C./min, inlet temperature: 320 ° C.
Carrier gas: helium Hexamethylene diamine / adipic acid unit, 6-aminocaproic acid unit, hexamethylene diamine / terephthalic acid unit were calculated from the measurement results of the above four components to obtain polyamide units.

The following were used as raw materials for producing polyamide.
1. Adipic acid / hexamethylene diammonium salt (AH salt): Trade name SEL NYLON-AH SALT (Rhodia)
2. ε-Caprolactam: Trade name CAPROLACTAM (Mitsubishi Chemical Corporation)
3. Terephthalic acid: Trade name QTA (Mitsubishi Chemical Corporation)
4). Hexamethylenediamine: Trade name 80HMD (Asahi Kasei Corporation)
5. Terephthalic acid / hexamethylene diammonium salt (6T salt): 20% by weight aqueous solution was used so that hexamethylenediamine and terephthalic acid were equimolar.

[Example 1]
A 150 L raw material adjustment tank is charged with 37.2 kg of AH salt, 6.6 kg of ε-caprolactam, 6.0 kg of 6T salt (6.0 kg) (1.2 kg as 6T salt), and 75.0 L of water in a nitrogen gas atmosphere. The raw material aqueous solution was adjusted to increase the temperature to 90 ° C. The liquid described above was fed into a 200 L autoclave by a quantitative pump over 60 minutes. After feeding, the internal temperature was raised to 260 ° C. while maintaining the autoclave internal pressure at 15 KG. It took 180 minutes for the temperature to rise to 260 ° C. after the end of liquid feeding. After completion of the temperature increase, the pressure in the autoclave was released to atmospheric pressure over 60 minutes, and a reduced pressure reaction was further performed until a predetermined stirring power was reached. The pressure at the end of the reaction was 470 torr. Stirring was stopped, nitrogen gas was introduced, and the autoclave was kept under pressure. Next, the molten copolymerized polyamide resin was extracted as a strand and pelletized, and the pellet was extracted and removed with boiling water, and the pellet was dried at 120 ° C. and 1 torr. The copolyamide thus obtained had a relative viscosity of 3.6 and a melting point of 235 ° C.

  To 100 parts by weight of the copolymer polyamide obtained above, 0.2 parts by weight of ethylenebisstearic acid amide is blended and extruded through a die having 24 holes with a diameter of 0.5 mm at an extrusion temperature of 250 ° C., An undrawn yarn was obtained. Thereafter, monofilaments were produced under the following monofilament production conditions 1. The obtained fine monofilament (diameter 0.077 mm) was evaluated for dry linear strength and dry nodule strength, and the results are shown in Table 1.

<Fine product monofilament manufacturing conditions 1>
Cooling water temperature: 15 ° C. Cold water First stage stretching: Temperature 98 ° C., steam atmosphere First stage stretching ratio: 3.5 times Second stage stretching: 160 ° C., hot air atmosphere Second stage stretching ratio: 1.71 times Heat setting Temperature: 160 ° C
Heat set relaxation rate: 2%
Overall draw ratio: 5.87 times

[Example 2]
In Example 1, the raw material composition was changed to 36.3 kg of AH salt, 7.1 kg of ε-caprolactam, and 20 kg of 6T salt 20% by weight aqueous solution to 8 kg. Got. In the same manner as in Example 1, undrawn yarns and fine drawn monofilaments were produced, and the physical property measurement results are shown in Table 1.

[Example 3]
In Example 1, ternary copolymerization was carried out in the same manner as in Example 1 except that the raw material charge composition was changed to 34.2 kg of AH salt, 8.7 kg of ε-caprolactam, and 10.5 kg of 20% aqueous solution of 6T salt. A polyamide resin was obtained. In the same manner as in Example 1, undrawn yarns and fine drawn monofilaments were produced, and the physical property measurement results are shown in Table 1.

[Comparative Example 1]
In a 200 L autoclave, 48 kg of ε-caprolactam was charged, sealed in a nitrogen gas atmosphere, heated to 150 ° C., and a separately adjusted 40% aqueous solution of 12 kg of AH salt was maintained at an internal temperature of 150 ° C. and an internal pressure of 2.5 KG. The solution was fed by a quantitative pump. After feeding, the internal temperature was raised to 260 ° C. while maintaining the internal pressure of the autoclave at 10 KG. After the temperature was raised, the pressure was released, and a reduced pressure reaction was performed until a predetermined stirring power was reached. Stirring was stopped and nitrogen gas was introduced to maintain the pressure at normal pressure. Next, the molten copolyamide was extracted from the autoclave as a strand and pelletized, and the unreacted monomer was extracted and removed using boiling water and dried. The copolyamide thus obtained had a relative viscosity of 3.5 and a melting point of 195 ° C. Thereafter, similarly to Example 1, undrawn yarns and fine drawn monofilaments were produced, and the physical property measurement results are shown in Table 1.

[Comparative Example 2]
A 200-liter autoclave was charged with 54 kg of ε-caprolactam, placed in a nitrogen gas atmosphere, sealed, heated to 150 ° C., and a 6% 6T salt 6 kg aqueous solution prepared separately was stirred at an internal temperature of 150 ° C. and an internal pressure of 2.5 KG. The solution was fed by a quantitative pump while maintaining the temperature. After feeding, the internal temperature was raised to 260 ° C. while maintaining the internal pressure of the autoclave at 10 KG. After the temperature was raised, the pressure was released, and a reduced pressure reaction was performed until a predetermined stirring power was reached. After introducing nitrogen gas and maintaining the pressure, it was extracted as a strand and pelletized, and unreacted monomer was extracted and removed using boiling water and dried. The copolyamide thus obtained had a relative viscosity of 3.5 and a melting point of 205 ° C. Thereafter, similarly to Example 1, undrawn yarns and fine drawn monofilaments were produced, and the physical property measurement results are shown in Table 1.

[Comparative Example 3]
A 200 L autoclave was charged with 52.2 kg of ε-caprolactam, placed in a nitrogen gas atmosphere, sealed, heated to 150 ° C., and separately adjusted 40% aqueous solution of 6.0 kg of AH salt and 1.8 kg of 6T salt was stirred. The liquid was fed by a quantitative pump while maintaining the internal temperature at 150 ° C. and the internal pressure at 2.5 KG. After feeding, the internal temperature was raised to 260 ° C. while maintaining the internal pressure of the autoclave at 10 KG. After the temperature was raised, the pressure was released, and a reduced pressure reaction was performed until a predetermined stirring power was reached. After introducing nitrogen gas and maintaining the pressure, it was extracted as a strand and pelletized, and unreacted monomer was extracted and removed using boiling water and dried. The relative viscosity of the copolymerized polyamide thus obtained was 3.75, and the melting point was 198 ° C. Thereafter, similarly to Example 1, undrawn yarns and fine drawn monofilaments were produced, and the physical property measurement results are shown in Table 1.

[Comparative Example 4]
A 150 L raw material adjusting tank was charged with 45.0 kg of AH salt and 67.5 kg of water in a nitrogen gas atmosphere to prepare an aqueous raw material solution, and the temperature was raised to 90 ° C. The raw material aqueous solution was fed into a 200 L autoclave by stirring with a quantitative pump. After feeding, the internal temperature was raised to 260 ° C. while maintaining the internal pressure of the autoclave at 15 KG. After the temperature was raised, the pressure was released, and a reduced pressure reaction was performed until a predetermined stirring power was reached. After introducing nitrogen gas and maintaining the pressure, it was extracted as a strand, pelletized, and then dried. The polyamide 66 thus obtained had a relative viscosity of 3.5 and a melting point of 264 ° C.

  Thereafter, production of a fine monofilament was attempted in the same manner as in Example 1. However, yarn breakage occurred frequently in the second stage drawing process, and no monofilament was obtained. Therefore, until the fine monofilament is stably obtained without causing yarn breakage, the second-stage draw ratio is lowered, the second-stage draw temperature is raised, and the heat is increased according to the fine monofilament production condition 2 shown below. A fine monofilament was produced by raising the fixing temperature. The obtained fine monofilament (diameter 0.072 mm) was evaluated for dry linear strength and dry nodule strength. The results are shown in Table 1.

<Manufacturing condition 2 for fine monofilament>
Cooling water temperature: 15 ° C. Cold water First stage stretching: 98 ° C., steam atmosphere First stage stretching ratio: 3.5 times Second stage stretching: 170 ° C., hot air atmosphere Second stage stretching ratio: 1.65 times Heat setting temperature : 170 ° C
Heat set relaxation rate: 2%
Overall draw ratio: 5.66 times

表１から明らかなように、本発明の３元系共重合ポリアミドからなるモノフィラメント釣り糸は、強度が優れていることが判明した。６Ｔ塩を欠く２元系ポリアミド（比較例１）は強度に劣り、６６塩を欠く２元系ポリアミド（比較例２）は更に強度に劣る。６／６６／６Ｔの３元系ポリアミドであっても６−アミノカプロン酸単位が主体のもの（比較例３）は強度の向上が見られるものの実用レベルには不足である。ポリアミド６６単独（比較例４）はポリアミドの融点が高くてモノフィラメントの延伸操作に難点があり、高温側で延伸倍率を小さくすると延伸は可能であるが、フィラメント物性に劣るものとなる。

As is clear from Table 1, it was found that the monofilament fishing line made of the ternary copolymer polyamide of the present invention has excellent strength. The binary polyamide lacking 6T salt (Comparative Example 1) is inferior in strength, and the binary polyamide lacking 66 salt (Comparative Example 2) is inferior in strength. Even in the case of 6/66 / 6T ternary polyamide, the main component of the 6-aminocaproic acid unit (Comparative Example 3) is insufficient for practical use although strength is improved. Polyamide 66 alone (Comparative Example 4) has a high melting point of polyamide and has a difficulty in stretching the monofilament, and if the stretch ratio is reduced on the high temperature side, stretching is possible, but the filament physical properties are poor.

  From Table 1, as a component of the polyamide resin, (1) an aliphatic polyamide unit composed of a diamine unit and an aliphatic dicarboxylic acid unit is 70 to 90% by weight, (2) a 6-aminocaproic acid unit is 8 to 30% by weight, (3) When the aromatic polyamide unit composed of an aromatic dicarboxylic acid unit and a diamine unit is in the range of 1 to 25% by weight, (1) is 75 to 85% by weight, (2) is 10 to 25% by weight, It can be seen that when (3) is 2 to 20% by weight, a remarkable effect is exhibited.

The polyamide resin provided by the present invention and the monofilament made of the polyamide resin can be expected to obtain excellent performance for tegus, fish nets and guts.

Claims (9)

  It contains a 6-aminocaproic acid unit, an aromatic dicarboxylic acid unit, an aliphatic dicarboxylic acid unit, and a diamine unit as a component of the polyamide resin, and the total content of the aliphatic dicarboxylic acid unit and the diamine unit is 6-aminocaproic acid unit The melting point when the temperature is increased from a molten state to 30 ° C. at a temperature decrease rate of 20 ° C./min and then increased at a temperature increase rate of 20 ° C./min using a differential scanning calorimeter. A polyamide resin having a temperature of 180 ° C. or higher and 250 ° C. or lower.   2. The polyamide resin according to claim 1, wherein the total content of the aromatic dicarboxylic acid unit and the diamine unit is 1 to 30% by weight.   The polyamide resin according to claim 1 or 2, wherein 70 to 100% by weight of the diamine unit is composed of an aliphatic diamine.   The constituent components of the polyamide resin are (1) 60 to 94% by weight of an aliphatic polyamide unit comprising a diamine unit and an aliphatic dicarboxylic acid unit, (2) 5 to 35% by weight of a 6-aminocaproic acid unit, and (3) aroma. The polyamide resin according to any one of claims 1 to 3, wherein the aromatic polyamide unit comprising an aromatic dicarboxylic acid unit and a diamine unit is 1 to 30% by weight.   The constituent components of the polyamide resin are (1) 60 to 94% by weight of an aliphatic polyamide unit comprising a diamine unit and an aliphatic dicarboxylic acid unit, (2) 5 to 35% by weight of a 6-aminocaproic acid unit, and (3) aroma. 1-30 wt% of aromatic polyamide units composed of aromatic dicarboxylic acid units and diamine units, and (4) 0-30 wt% of polyamide units other than aliphatic polyamide units, 6-aminocaproic acid units, and aromatic polyamide units. The polyamide resin according to any one of claims 1 to 3, wherein   The monofilament which consists of a polyamide resin of any one of Claims 1-5, and whose diameter is 0.005-0.5 mm.   A fishing line comprising the monofilament according to claim 6.   The polycondensation raw material is subjected to polycondensation in the same reaction system using ε-caprolactam, a diamine containing an aliphatic diamine as a main component, an aliphatic dicarboxylic acid and an aromatic dicarboxylic acid. 6. The method for producing a polyamide resin according to any one of 5 above. The method for producing a polyamide resin according to claim 8, wherein 70 to 100% by weight of the diamine is composed of an aliphatic diamine.