JPH04214408A - Polyamide monofilament - Google Patents

Abstract

PURPOSE:To provide a polyamide monofilament having extremely excellent transparency, excellent flexibility, resistant to the lowering of mechanical strength and especially suitable as a material for long-line fishing. CONSTITUTION:The objective polyamide monofilament is composed of a copolymerized polyamide resin containing a dimerized fatty acid component as a copolymerized component.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to monofilaments made of specific copolyamides. Specifically, the present invention provides a polyamide monofilament with excellent flexibility and transparency, and is particularly useful as a longline material for fishing.

0002

BACKGROUND OF THE INVENTION Polyamides have excellent mechanical properties, heat resistance and cold resistance, and are therefore widely used in injection molded products, films and monofilaments, typified by automobile parts. One of the main uses of polyamide monofilament is 0.05%, which is used as fishing material.
There are applications for thick monofilaments of 5 mm or more. Such thick monofilaments are generally required to be easy to bundle and knot, so flexibility is required, and transparency is required because it is better if they are difficult for fish to see.

By the way, although various types of copolyamides have been used for such thick monofilaments, they have been insufficient in flexibility and transparency. Therefore, in order to improve the flexibility, efforts have been made to incorporate caprolactam, a typical plasticizer for polyamide (for example, JP-A-64-85315).

[0004] However, if the addition of caprolactam is small, the effect will not be sufficiently exhibited, so addition of about 10% by weight is carried out, but caprolactam is highly deliquescent and must be kept in a dry state when blended into polyamide pellets. However, there were significant problems in terms of work. Furthermore, since the melting point of caprolactam is as low as 60 to 70°C, it may be melted by the heat of the extruder, making it unstable to feed into the extruder.

[0005] Also, at a molding temperature of 250°C, it volatilizes violently.
It emits fumes and its vapors are harmful to humans. Furthermore, when caprolactam is added in a large amount of 10% by weight, the strength of the thick monofilament is reduced, which is also a problem.

[0006]

[Means for Solving the Problems] The present inventors have solved the deterioration of workability and the decrease in strength during production of the above-mentioned caprolactam-added thick monofilament, and also achieved excellent flexibility and especially transparency. After conducting extensive studies to provide a thick monofilament, the inventors discovered that the purpose could be achieved by using a specific copolyamide resin, and thus arrived at the present invention.

That is, the gist of the present invention resides in a polyamide monofilament made of a copolyamide resin containing a dimerized fatty acid component as a copolymerization component. The present invention will be explained in detail below.

The copolyamide resin used in the present invention is mainly composed of a lactam having three or more membered rings, a polymerizable ω-amino acid, or one type of polycondensation component for polyamide consisting of a dibasic acid and a diamine, or It consists of two or more types. These polycondensation components for polyamide are:
Specifically, ε-caprolactam, enantlactam,
Those derived from lactams such as capryllactam, lauryllactam, α-pyrrolidone, α-piperidone, 6-aminocaproic acid, 7-aminoheptanoic acid, 9
- derived from ω-amino acids such as aminononanoic acid, 11-aminoundecanoic acid, adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecadionic acid, hexadecadione Acid, hexadecenedioic acid, eicosandioic acid, eicosadienedionic acid, diglycolic acid, 2,
Dibasic acids such as 2,4-trimethyladipic acid, xylylene dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, terephthalic acid, isophthalic acid, hexamethylene diamine, tetramethylene diamine, nonamethylene diamine, undecamethylene diamine , dodecamethylene diamine, 2,2,4 (or 2,4,4)-trimethylhexamethylene diamine, bis-(4,4'-aminocyclohexyl)methane, and diamines such as metaxylylene diamine. Examples include things. Among these, preferred is a polycondensation component consisting of ε-caprolactam or a polycondensation component consisting of hexamethylene diamine and adipic acid.

On the other hand, the dimerized fatty acid that induces the dimerized fatty acid component, which is a copolymerization component, is a fatty acid such as a saturated, ethylenically unsaturated, or acetylenically unsaturated fatty acid having 8 to 24 carbon atoms, preferably 12 to 24 carbon atoms. It is a polymerized fatty acid obtained by polymerizing saturated, natural or synthetic monobasic fatty acids. Among these, ethylenically unsaturated fatty acids are preferred, and specific examples include linolenic acid, linoleic acid, oleic acid, dimers of tall oil fatty acids, and the like.

[0010] Commercially available polymerized fatty acids usually have dimerized fatty acids as the main component and also contain raw material monomer acids and trimerized fatty acids, but the dimerized fatty acid content is 60% by weight. %
or more, preferably 70% by weight or more, particularly preferably 95% by weight or more
It is preferable that the amount is at least % by weight. Furthermore, commercially available polymerized fatty acids can be distilled to increase the content of dimerized fatty acids.

The content of dimerized fatty acids in the polyamide resin is selected in the range from 25 to 60% by weight, preferably from 30 to 55% by weight. Dimerized fatty acid content is 25% by weight
If it is less than 60% by weight, the resulting monofilament will have insufficient flexibility and transparency, and if it is more than 60% by weight, polycondensation of the copolyamide resin will become difficult and the transparency of the monofilament will deteriorate.

[0012] The copolyamide resin of the present invention is produced using a prepolymer produced from a dimerized fatty acid and a diamine, although there are no particular restrictions on the production method. Polyamides obtained by polycondensation with other polyamide raw materials are used. Here, the above-mentioned ethylenically unsaturated fatty acids and the like are preferably used as the dimerized fatty acids.

[0013] Further, diamines used in producing the prepolymer together with dimerized fatty acids include ethylene diamine, 1,4-diaminobutane, hexamethylene diamine, nonamethylene diamine, undecamethylene diamine, dodecamethylene diamine, 2, 2, 4 (or 2,
4,4)-Trimethylhexamethylene diamine, bis-
Examples include diamines such as (4,4'-aminocyclohexyl)methane and metaxylylene diamine.

In order to produce a prepolymer from a dimerized fatty acid and a diamine, for example, the dimerized fatty acid, diamine and water are placed in a pressurized container and reacted by heating. The reaction may be started and stopped when the desired number average molecular weight is reached. The number average molecular weight of the prepolymer produced from the dimerized fatty acid and diamine is 1,000 to 50, as determined by the end group quantitative method.
It is necessary to be within the range of 000, preferably 2
,000 to 30,000, more preferably 3,000 to
8,000.

[0015] The terminal group quantitative method is a method in which the amount of amino groups and carboxyl groups, which are the terminal groups of polyamide, is determined to determine the total amount of end groups, and the amount is calculated from this and the weight of the polymer.

Quantification of the amount of terminal groups in the terminal group determination method is as follows:
Amino groups are measured by dissolving the polyamide in phenol and titrating with 0.05N hydrochloric acid, and carboxyl groups are measured by dissolving the polyamide in benzyl alcohol and titrating with 0.1N caustic soda. The total amount of terminal groups is the sum of the terminal amino groups and terminal carboxyl groups determined in this way.

In the present invention, if the number average molecular weight is too low outside the above range, a copolyamide cannot be formed and a product with sufficient flexibility cannot be obtained. On the other hand, if the temperature is too high outside the above range, the resulting copolyamide will undergo phase separation, resulting in peeling of the molded product. In a preferred method for producing the copolyamide resin of the present invention, the prepolymer produced from the above-mentioned dimerized fatty acid and diamine is polycondensed with other polyamide raw materials other than the prepolymer component.

The other polyamide raw materials used here are raw materials that provide the above-mentioned polycondensation component for polyamide as the main component of the copolyamide resin of the present invention. That is,
A lactam having three or more membered rings, a polymerizable ω-amino acid, a salt obtained by reacting a dibasic acid with a diamine, or a prepolymer thereof is used. As raw materials for these polyamides, the compounds mentioned above are used as raw materials for providing polycondensation components for polyamides, which are the main components of the copolyamide resin of the present invention. Specifically, lactams such as ε-caprolactam, 6- Examples include ω-amino acids such as aminocaproic acid, salts of dibasic acids such as adipic acid, and diamines such as hexamethylene diamine, and the like.

When these polyamide raw materials are prepolymers, the number average molecular weight is preferably 15,000 or less, preferably 10,000 or less. If this number average molecular weight is too high, the resulting copolyamide will undergo phase separation. In order to produce the copolyamide resin of the present invention, a prepolymer produced from a dimerized fatty acid and a diamine and polyamide raw materials other than the prepolymer components are charged into a polymerization reaction vessel, and according to the usual polyamide production method. All you have to do is polymerize.

The number average molecular weight of the copolyamide resin of the present invention is 15,000 to 40,000, preferably 20.0
It is about 00 to 40,000. Since the copolyamide resin of the present invention only needs to contain a predetermined amount of the dimerized fatty acid component, the structure of the polymer itself is not particularly limited. Although the structure may be different, it is usually a block polymer or random polymer in which several prepolymer units formed from a dimerized fatty acid and a diamine are introduced into one molecular chain.

In the present invention, instead of the combination of dimerized fatty acid and diamine, a combination of dimerized diamine obtained from the above dimerized fatty acid and the above-mentioned dibasic acid may be used. You can also do it. In the present invention, in addition to the above-mentioned copolyamide resin, a small amount of one or more other polyamides may be added to the extent that the object of the present invention is not impaired. Examples of the other polyamides include nylon 6, nylon 66, nylon 6/66, nylon 11,
Nylon 12, nylon 6/6T, nylon 6I/6T
Examples include.

Further, other resins such as ionomer resins, acid-modified polyethylene, acrylic rubber, polyester resins, polyester elastomers, etc. can also be added. When such other resins are added, transparency generally tends to deteriorate to some extent, but they can be suitably added to improve flexibility. The copolyamide of the present invention also contains various additives well known to thermoplastic resins, such as various stabilizers, reinforcing agents, pigments, dyes, lubricants, ultraviolet absorbers, antiblocking agents, and crystallization promoters. It's okay to do that. Naturally, a plasticizer such as caprolactam or its oligomer may be added.

[0023] Furthermore, in the present invention, a bisamide compound represented by the general formula below can be further blended with the copolyamide resin, if necessary.

The bisamide compound used in the present invention is
general formula

[0025]

[Chemical formula 1]

[0026] or

[0027]

[Case 2]

(In the formula, R1 is a divalent hydrocarbon residue, R
2 and R3 are monovalent hydrocarbon residues, and R4 and R5 are hydrogen atoms or monovalent hydrocarbon residues.

The bisamide compound represented by the above general formula (1) includes methylenediamine, ethylenediamine,
Alkylene diamines such as propylene diamine, butylene diamine, hexamethylene diamine, octamethylene diamine, and dodecamethylene diamine; arylene diamines such as phenylene diamine and naphthylene diamine; diamines such as arylene dialkyl diamines such as xylylene diamine, stearic acid, and hexane. alkylene bis fatty acid amides, arylene bis fatty acids obtained by reaction with fatty acids such as acid, octanoic acid, decanoic acid, lauric acid, myristic acid, palmitic acid, arachidic acid, behenic acid, oleic acid, elaidic acid, montanic acid, etc. It refers to all amides, arylene dialkylene bis fatty acid amides, etc., but preferably N,N'-methylene bis stearic acid amide and N,N'-ethylene bis stearic acid amide are mentioned.

Further, the bisamide compound represented by the general formula (2) includes alkylamines such as ethylamine, methylamine, butylamine, hexylamine, decylamine, pentadecylamine, octadecylamine, and dodecylamine; and arylamines such as aniline and naphthylamine. amines; aralkylamines such as benzylamine; cycloalkylamines such as cyclohexylamine; As expected, N, N'-
A typical example is dioctadecyl dibasic acid amide such as diotadecyl terephthalic acid amide.

These bisamide compounds, regardless of the compounds represented by the above general formulas (1) and (2), may be used alone or as a mixture.

Blending such a bisamide compound is particularly preferred when cooling is performed with water, since the effect of improving transparency is remarkable. The amount of these bisamide compounds added is 0.1 to 0.5 parts by weight, especially 0.
．． 15 to 0.4 parts by weight is preferred. If the amount added is too large, white spots may occur in the monofilament due to insufficient kneading, or stable spinning may become impossible. On the other hand, if the amount is too small, the effect of improving transparency and flexibility will be small.

The monofilament of the present invention is made of the above-mentioned copolyamide resin (or a copolyamide resin composition blended with other resins, bisamide compounds, etc. as necessary), and preferably has a diameter of 0. 5m
The monofilament has a diameter of 1 mm or more, more preferably 1 mm or more, particularly preferably 5 mm to 10 mm in diameter.

The monofilaments made of the copolyamides of the present invention have an unexpectedly high degree of transparency compared to monofilaments made of polyamide materials used in conventional monofilaments. Here, since it is difficult to measure the transparency of a monofilament using a conventional method for measuring the transparency of a fiber, an optopower meter manufactured by Hakutronics Co., Ltd. is used in the present invention.

The measured transparency of the monofilament of the present invention is such that the light transmittance is -15 dBm (decibel) or more, preferably -12 dBm or more. Also,
Normally, the transparency of a monofilament decreases as the thickness increases, but in the present invention, even a thick monofilament with a diameter of 5 to 10 mm can maintain a high transparency of -15 dBm.

Next, a preferred method for producing the polyamide monofilament of the present invention using the above-mentioned copolyamide will be explained. Melt spinning can be carried out using conventional methods and conditions, i.e., using an extruder to
This is possible by spinning from a nozzle at a temperature range of ~60°C.

[0037] Immediately after melt spinning, it is cooled with water at a temperature of 25°C or less. At this time, if the cooling temperature is too high, transparency will deteriorate, which is not preferable, and a temperature range of 1 to 15° C. is good in terms of transparency. Next, the first stretching step is carried out, and the temperature in this step is important for the purpose of the present invention, that is, as a manufacturing condition for achieving both transparency and flexibility.

The drawing temperature in this step is lower than the temperature normally employed for drawing polyamide monofilaments, and is 10 to 100°C, preferably 30 to 80°C. If this temperature is too low, flexibility will be lacking, and if this temperature is too high, transparency will decrease. Note that the medium for keeping the yarn at a constant temperature may be any medium such as air, hot water, or steam. In addition, the stretching ratio at that time is preferably 2.0 to 5.0 times; if it is too high or too low, the strength will decrease and stable stretching will not be possible. In addition, the length of the bathtub used for this stretching is 0.5 to 2 m.
, preferably 0.5 to 1 m.

The stretching conditions and annealing conditions for the subsequent second stage may be within a range that does not impair transparency and flexibility within the conditions for ordinary polyamide monofilament; Preferably 200-30
Stretching conditions are 1.1 to 3.0 times in heated air at 0°C, annealing is 150 to 350°C, preferably 200 to 30°C.
It is sufficient to adopt a relaxing condition of 0.9 to 1.0 times in heated air at 0°C.

In the present invention, stretching is carried out in each of the above-mentioned steps, and the overall stretching ratio is 4 to 10 times, preferably 5 to 8 times, which is higher than that of ordinary polyamide. It is preferable to stretch the film. If the stretching ratio is too low, transparency will decrease. Here, the overall stretching ratio is determined as the product of the stretching ratios of each stretching process.

Thus, the polyamide monofilament obtained by the present invention has a transparency that has not been previously obtained, especially a light transmittance of -1 measured with the above-mentioned optopower meter.
It is a monofilament with high transparency of 5 dBm (minus 15 decibels) or more and excellent flexibility. (Here, the larger the value of the light transmittance measured with an optopower meter, that is, the closer it is to 0, the better the transparency.) The monofilament of the present invention is
Utilizing these unique properties, it is suitably used as a longline material for fishing, especially as a material for tuna longline. For example, it is used for the main line, branch line, weir part, fishing head part, etc. that make up the longline, and it is particularly preferable to use thick monofilament for the main line part. That is, this main rope part was conventionally
In order to make the rope thicker, twine was used, but in the present invention, since the thread itself can be made thicker, it is also possible to construct the rope with a single thread, making it possible to create a rope with a simpler structure. I can do it.

[0042]

【Example】

Hereinafter, the present invention will be specifically explained with reference to Examples. Production of copolyamide polyamide In a 200 liter autoclave, 25 kg of ε-caprolactam, 4.0 kg of water, 20 kg of polymerized fatty acid whose main component is dimerized fatty acid (trade name: Enpol 1010, manufactured by Henkel), and 80% by weight. Hexamethylene diamine aqueous solution (5.0 kg) was charged in each case, the temperature and pressure were increased to 270°C and 14 kg/cm2 in a closed atmosphere under a nitrogen atmosphere, and the pressurized reaction was carried out for 3 hours with stirring, and then the pressure was gradually released to 200 kg/cm2. The pressure was reduced to Torr, and the reaction was carried out under reduced pressure for 2 hours. Stirring was stopped, nitrogen was introduced to restore the pressure to normal pressure, the mixture was extracted as a strand and pelletized, unreacted monomers were extracted and removed using boiling water, and vacuum drying was performed. The obtained copolyamide contained 41% by weight of the dimerized fatty acid component.

Example 1 and Comparative Examples 1 to 2 The above copolyamide or ordinary nylon 6/66 copolymer (66
Components: 15% by weight) and other components shown in Table 1 were dry blended and then melt-spun at a temperature of 230°C. This was solidified with cooling water at a water temperature of 8°C, and then drawn under the conditions shown in Table 2 to obtain a drawn monofilament with a diameter of 2 mm.

Table 3 shows the transparency and Young's modulus of the obtained monofilament. Here, Young's modulus and wet nodule strength are values measured according to JIS L-1013. The smaller the value of Young's modulus, the better the flexibility. In addition, transparency is achieved by an optopower meter (
The test was carried out using Hactronics Co., Ltd.). This indicates that the larger the value, the better the transparency.

Comparative Example 2 containing caprolactam
However, after 1 to 2 hours, the feeding into the extruder became unstable. The reason for this is thought to be that caprolactam was melted by water and the heat of the extruder. Further, in Comparative Example 2, during melt spinning, smoke was generated violently and caprolactam adhered to the periphery of the die. In Example 1, that is, an example using the copolyamide of the present invention, no smoke was observed. Example 2
Stretching was carried out in the same manner as in Example 1, except that the diameter of the monofilament was 6 mmφ and the stretching conditions were as shown in Table 2, to obtain a stretched monofilament with a diameter of 6 mm. Various physical properties are shown in Table 3.

[0046]

[Table 1]

[0047]

[Table 2]

[0048]

[Table 3]

[0049]

As described above, according to the present invention, it is possible to obtain a polyamide monofilament which has good continuous moldability and is excellent in all three aspects of transparency, flexibility, and knot strength.

Claims (2)

[Claims] 1. A polyamide monofilament comprising a copolyamide resin containing a dimerized fatty acid component as a copolymerization component. 2. The polyamide monofilament according to claim 1, wherein the content of the dimerized fatty acid component is 25 to 60% by weight based on the copolyamide resin.