JPH01260047A - Fishnet and rope for pulling same - Google Patents

Abstract

PURPOSE:To provide a lightweight fishnet of high mechanical strength, excellent in resistance to water and saline water, consisting of a molecularly oriented form of ultra-high-molecular weight polyolefin with an intrinsic viscosity at or higher than a specified value. CONSTITUTION:The objective fishnet consisting of a molecularly oriented form of ultra-high-molecular weight polyolefin with an intrinsic viscosity of >=5dl/g (pref. 7-30dl/g). Preferably, said form is of a ultra-high-molecular weight ethylene-alpha-olefin copolymer with the content of >=3C alpha-olefin (pref., butene-1,4- methylpentene-1, hexene-1, octene-1 or decene-1) being, on average, 0.1-20 (pref. 0.5-10) per 1,000 carbon atoms.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to fishing nets and ropes for pulling fishing nets, and more particularly, the present invention relates to fishing nets and ropes for pulling fishing nets, and more particularly, the present invention relates to fishing nets and ropes for pulling fishing nets, and more particularly, the present invention relates to fishing nets and ropes for pulling fishing nets, and more particularly, the present invention relates to fishing nets and ropes for pulling fishing nets. Regarding fishing nets and fishing net towing ropes with excellent water resistance, more specifically, they are made of molecularly oriented ultra-high molecular weight ethylene/α-olefin copolymer and have excellent creep resistance, weather resistance and impact resistance. Concerning fishing nets and ropes for towing fishing nets.

7 mouths < 1 of the day and ■ of the day.

Fishing nets or ropes for towing fishing nets, especially fishing nets for trawls, are desired to be lightweight and thin in order to save on fuel consumption and improve efficiency of ships. Conventionally, such fishing nets or ropes for towing fishing nets have been made of polyethylene fibers, polypropylene fibers, or nylon fibers. However, fishing nets made of these fibers have many problems that need to be improved in terms of mechanical strength and the like.

It is already known that a molecularly oriented molded article having high elastic modulus and high tensile strength can be obtained by forming ultra-high molecular weight polyethylene into fibers, tapes, etc. and stretching the fibers. For example, in Japanese Patent Application Laid-Open No. 56-15408,
Spinning dilute solutions of ultra-high molecular weight polyethylene and drawing the resulting filaments is described. Also,
JP-A-59-130313 discloses that ultra-high molecular weight polyethylene and wax are melt-kneaded, the kneaded product is extruded, cooled and assimilated, and then stretched, and JP-A-59-187614 describes , it is described that the above melt-kneaded product is extruded, drafted, cooled and solidified, and then stretched.

1. Additional information The present invention attempts to solve the problems associated with the above-mentioned conventional technology, and can be made lightweight and thin.
Moreover, it is our aim to provide fishing nets and fishing net traction ropes that have excellent mechanical strength and impact resistance, as well as excellent creep resistance and abrasion resistance.

A fishing net or a rope for pulling a fishing net according to the present invention is characterized by being made of a molecularly oriented molded article of ultra-high molecular weight polyolefin having an intrinsic viscosity [η] of at least 5 dl/g, and furthermore, has an intrinsic viscosity [η] of at least 5 dl/g [Consisting of an ultra-high molecular weight ethylene/a-olefin copolymer having an η of at least 5 dl/g and an average content of α-olefins having 3 or more carbon atoms from 011 to 20 per 1000 carbon atoms. There is.

Fishing nets and fishing net traction ropes made of molecularly oriented molded ultra-high molecular weight polyolefins are lightweight, high-strength, and have excellent water and salt water resistance.
The molecularly oriented molded product of α-olefin copolymer has excellent strength, abrasion resistance, weather resistance, water resistance, and salt water resistance, as well as excellent creep resistance and impact resistance. A wide variety of braiding methods can be used to manufacture ropes from molecularly oriented materials, and the strength utilization rate when forming ropes is high.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The fishing net and fishing net towing rope according to the present invention will be specifically described below.

First, a molecularly oriented molded product of an ultra-high molecular weight polyolefin, particularly a molecularly oriented molded product of an ultra-high molecular weight ethylene/α-olefin copolymer, which constitutes the fishing net and rope for towing a fishing net according to the present invention will be explained.

The molecularly oriented molded product used in the present invention is a molecularly oriented molded product of an ultra-high molecular weight polyolefin or a molecularly oriented molded product of an ultra-high molecular weight ethylene/α-olefin copolymer.

Specifically, the ultra-high molecular weight polyolefin constituting the molecularly oriented molded article of the present invention includes ultra-high molecular weight polyethylene,
Examples include ultra-high molecular weight polypropylene, ultra-high molecular weight poly-1-butene, and ultra-high molecular weight copolymers of two or more types of α-olefins. This molecularly oriented molded article of ultra-high molecular weight polyolefin is lightweight, has high strength, and has excellent water resistance and salt water resistance.

Further, as the ultra-high molecular weight ethylene/α-olefin copolymer constituting the molecularly oriented molded article of the present invention, ultra-high molecular weight ethylene/propylene copolymer, ultra-high molecular weight ethylene/
1-butene copolymer, ultra-high molecular weight ethylene/4-methyl-1-pentene copolymer, ultra-high molecular weight ethylene/1-hexene copolymer, ultra-high molecular weight ethylene/1-octene copolymer, ultra-high molecular weight Ethylene such as ethylene/1-decene copolymer and the number of carbon atoms is 3 to 20, preferably 4 to 1
An example is an ultra-high molecular weight ethylene/α-olefin copolymer with 0 α-olefin. In this ultra-high molecular weight ethylene/α-olefin copolymer, the α-olefin having 3 or more carbon atoms contains 1 to 20 O2, preferably 0.5 to 10, and more preferably 1 to 20 O2 per 1000 carbon atoms of the polymer. It is contained in an amount of 7.

The molecularly oriented molded product obtained from such ultra-high molecular weight ethylene/α-olefin copolymer has particularly good impact resistance and creep resistance compared to the molecularly oriented molded product obtained from ultra-high molecular weight polyethylene. Are better. This ultra-high molecular weight ethylene/α-olefin copolymer is lightweight and has high strength, and has excellent abrasion resistance, @♀ resistance, and creep resistance, as well as excellent weather resistance, water resistance, and salt water resistance.

The ultra-high molecular weight polyolefin or ultra-high molecular weight ethylene/α-olefin copolymer constituting the molecularly oriented molded article of the present invention has an intrinsic viscosity [η] of 5 d, Il, / g or more, preferably 1-< is 7 to 30 dJl. /, and the molecularly oriented molded product obtained from this copolymer has excellent weaving properties and heat resistance. That is, since molecular terminals do not contribute to fiber strength and the number of molecular terminals is the reciprocal of the molecular weight (viscosity), a material with a large intrinsic viscosity [η] gives high strength.

The density of the molecularly oriented molded product of the present invention is 0.940 to 0.9
90Ir/cla preferably 0.960-Q, 935g
/ail. Here, the density is the usual method (^STHD 1
505), it was measured by the density gradient tube method. The density gradient tube at this time was prepared by using carbon tetrachloride and toluene, and the measurement was performed at room temperature (23° C.).

Dielectric constant of the molecularly oriented molded product of the present invention (IKHz, 23°C)
is 1.4 to 3.0 preferably 1.8 to 2.4,
Positive electric loss tangent (IKH7, 80℃) is 0.05 to 0.08
% is preferably 0.040 to o, oio%. Here, the dielectric constant and the positive electric dissipation tangent were measured using ^STHD 150 using a film-like sample in which fibers and tape-like oriented molecules were closely aligned in one direction.

The stretching ratio of the molecularly oriented molded article of the present invention is 5 to 80 times, preferably 10 to 50 times.

The degree of molecular orientation in the molecularly oriented molded product of the present invention is
When the ultra-high molecular weight polymer of the present invention is a drawn filament, for example, Yukichi Go, Teru Kubo: Kogyo T Magazine No. 39
Vol., p. 992 (1939), the degree of orientation according to the half-value, i.e., the equation (where ii '' is the half-value of the intensity distribution curve along the Debye ring of the strongest baratropic plane on the equator; The degree of orientation (F) defined by the width (°) is 0.90 or more, especially 0.9
From the viewpoint of mechanical properties, it is desirable that the molecules be oriented so that the number of particles is 5 or more.

Furthermore, the molecularly oriented molded product of the present invention has excellent mechanical properties, for example, in the form of a drawn filament,
an elastic modulus of more than a, especially more than 30 GPa, and 1.2 GPa
In particular, it has a tensile strength of 1.5 GPa or more.

The impulse voltage breakdown value of the molecularly oriented molded product of the present invention is 1
10-250KV/view preferably 150-220K
V/mth. Impulse voltage breakdown value was measured using the same sample as in the case of dielectric constant, and using brass < 25mφ on a copper plate.
) JIS type electrode, negative polarity impulse is 2KV.
The pressure was increased while adding in steps of /3 times, and the measurement was performed.

When the molecularly oriented molded product of the present invention is a molecularly oriented molded product of an ultra-high molecular weight ethylene/α-olefin copolymer, this molecularly oriented molded product has extremely excellent impact resistance, breaking energy, and creep resistance. It has the characteristic of being The characteristics of these molecularly oriented molded products of ultra-high molecular weight ethylene/α-olefin copolymers are expressed by the following physical properties.

The breaking energy of the molecularly oriented molded product of the ultra-high molecular weight ethylene/α-olefin copolymer used in the present invention is +r
-m/r or more, preferably 10 kg -m/g or more.

Moreover, the molecularly oriented molded article of the ultra-high molecular weight ethylene/α-olefin copolymer of the present invention has excellent creep resistance. In particular, it has outstanding creep resistance at high temperatures, which corresponds to the conditions that promote cleaving properties at room temperature.
As the % breaking load, the creep calculated as elongation (%) after 90 seconds at an ambient temperature of 70 °C is 7% or less, especially 5% or less, and the creep rate (ε, 5ec) is less than 4 x 10-4 sec-', especially less than 5 x 10-''sec-1.

Among the molecularly oriented materials of the present invention, ultra-high molecular weight ethylene/α
-The molecularly oriented olefin copolymer has the above-mentioned room-temperature properties, but if it also has the following thermal properties in addition to these room-temperature properties, the above-mentioned room-temperature properties can be further improved. However, it is preferable because it also has excellent heat resistance.

The molecularly oriented molded product of the ultra-high molecular weight ethylene/α-olefin copolymer used in the present invention has at least one crystal melting peak at a temperature at least 20°C higher than the original crystal melting temperature (Ti) of the copolymer. The heat of fusion based on (Tp) is 15% or more, preferably 20% or more, particularly 30% or more.

Ultra-high molecular weight ethylene copolymer original crystal melting temperature (T1
1) is by completely melting this molded body and then cooling it.
A method of raising the temperature again after relaxing the molecular orientation in the compact, the so-called second heating method in a differential scanning calorimeter.
It can be found by running.

To explain further, in the molecularly oriented molded article of the present invention, there is no crystal melting peak at all in the above-mentioned crystal melting temperature range inherent to the copolymer, or even if it exists, it exists only as a very slight tailing. , crystal melting peak (
Tp) is generally within the temperature range 711+20°C to Tl+50
℃, particularly in the region of TIl+20°C to Tn+100°C, and this peak (Tp) often appears as a plurality of peaks within the above temperature range. That is, this crystal melting peak (Tp) is within the temperature range T
High temperature side melting peak (TIEl) at n+35°C to TI+100°C and temperature range TI+20°C to TI+35°C
Tp and Tp2 often appear separated into two peaks, the low-temperature side melting peak ('rp2), and depending on the manufacturing conditions of the molecularly oriented molded product, Tp and Tp2 may further consist of a plurality of peaks.

These high crystal melting peaks ('rp,'rp2
) is said to significantly improve the heat resistance of molecularly oriented molded products of ultra-high molecular weight ethylene/α-olefin copolymers and contribute to strength retention or elastic modulus retention after high-temperature thermal history. Seem.

Further, it is desirable that the sum of the heat of fusion based on the high temperature side melting peak ('rp1') in the temperature range Tn+35°C to Tn+100°C is 1.5% or more, particularly 3.0% or more, based on the total heat of fusion.

In addition, as long as the sum of the heat of fusion based on the high temperature n melting peak (Tpl) satisfies the above value, if the high temperature side melting peak ('rp1) does not stand out as a main peak, that is, a collection of small peaks. Even if the peak becomes large or broad, the heat resistance may be slightly lost, but the creep resistance is excellent.

The melting point and heat of crystal fusion in the present invention were measured by the following method.

The melting point was determined using a differential scanning calorimeter as follows.

Differential scanning calorimeter is DSCn type (manufactured by PerkinElmer)
was used. The sample size is approximately 3 cm 4 fall x 4 nu
n, the orientation direction was restrained by wrapping it around an aluminum plate with a thickness of 0.2 fl. The sample wound around the aluminum plate was then sealed in an aluminum pan and used as a measurement sample. Also,
The aluminum pan, which is normally empty and placed in the reference holder, was filled with the same aluminum plate used for the sample to maintain heat balance. First, the sample was held at 30° C. for about 1 minute, and then the temperature was raised to 250° C. at a rate of 10° C./min, and the melting point measurement at the first heating was completed. Subsequently, the temperature was held at 250°C for 10 minutes, then the temperature was lowered at a rate of 20°C/min, and the sample was further held at 30°C for 10 minutes.

Then, the second heating was carried out at a heating rate of 10°C/min to 250°C.
When the temperature is raised to 'C, and at this time the temperature is raised for the second time (second run)
Melting point measurements were completed. At this time, the maximum value of the melting peak was taken as the melting point. If it appears as a shoulder,
A tangent was drawn at the inflection point immediately on the low-temperature side of the shoulder and the inflection point immediately on the high-temperature side, and the intersection was taken as the melting point.

In addition, from the straight line (baseline) connecting the 60°C and 240°C points of the endothermic curve and the original crystal melting temperature (T1) of the ultra-high molecular weight ethylene copolymer, which is determined as the main melting peak at the second temperature increase, A perpendicular line is drawn to the high point of ℃, and the part on the low temperature side surrounded by these is based on the crystal melting (TI) inherent to the ultra-high molecular weight ethylene copolymer, and the part on the high temperature side is based on the function of the molded article of the present invention. The crystal melting that occurs (
Tt+), and the heat of fusion of each crystal was calculated from these areas. Also, Tpl and T1
The heat of fusion based on the melting of TI
The part surrounded by the perpendicular line from +20°C and the perpendicular line from Tn+35°C was taken as the heat of fusion based on the melting of Tp2, and the high temperature side part was calculated in the same way as the heat of fusion based on the melting of Tpl.

The drawn filament of the ultra-high molecular weight ethylene/α-olefin copolymer of the present invention has a strength retention rate of 95% or more and an elastic modulus retention rate of 90% or more after being subjected to a heat history of 5 minutes at 170°C. In particular, it has an excellent heat resistance of 95% or more, which is completely unrecognizable in conventional drawn polyethylene filaments.

Notice of Molecular Orientation of Ultra-High Molecular Weight Polyolefin -S As a method for obtaining the above-mentioned drawn ultra-high molecular weight polyolefin having high elasticity and high tensile strength, for example, JP-A No. 5
Publication No. 6-15408, Japanese Unexamined Patent Publication No. 58-5228,
JP-A-59-130313, JP-A-59-187
The stretchability of ultra-high molecular weight polyolefin can be improved by making ultra-high molecular weight polyolefin into a dilute solution, or by adding a low molecular weight compound such as paraffin wax to ultra-high molecular weight polyolefin, as described in detail in Publication No. 614, etc. An example of an improved method for stretching to a high magnification can be given.

Ultra-high molecular weight ethylene and α-olefins are lacking in lithium.”
Next, the present invention will be explained below in order of raw materials, manufacturing method, and purpose so that it can be easily understood.

The ultra-high molecular weight ethylene/α-olefin copolymer used in the present invention can be obtained by slurry polymerizing ethylene and an α-olefin having 3 or more carbon atoms using a Ziegler catalyst, for example, in an organic solvent. It is obtained by

As the α-olefin having 3 or more carbon atoms, propylene, butene-1, pentene-1,4-methylpentene-1
, hexene-1, heptene-1, octene-1, etc. are used, but among these, butene-1,4-methylpentene-1, hexene-1, octene-1, etc. are particularly preferred.Such α-olefins are is copolymerized with ethylene in the amount stated above per 1000 carbon atoms of the resulting copolymer. In addition, ultra-high molecular weight ethylene α-
The olefin copolymer should have a molecular weight corresponding to the aforementioned intrinsic viscosity [η].

The α-olefin component in the ultra-high molecular weight ethylene/α-olefin copolymer used in the present invention is determined using an infrared spectrophotometer (manufactured by JASCO Corporation). Specifically, the absorbance at 1378 cm-', which represents the bending vibration of the methyl group of the α-olefin incorporated into the ethylene chain, was measured using an infrared spectrophotometer, and this value was determined in advance by 13C nuclear magnetic resonance. Using the equipment, quantify the amount of α-olefin in the ultra-high molecular weight ethylene/α-olefin copolymer by converting it into the number of methyl branches per 1000 carbon atoms using a calibration curve created using a model compound. .

In the present invention, when producing a molecularly oriented product from the ultra-high molecular weight ethylene/α-olefin copolymer, a diluent is added to the copolymer. As such a diluent, a solvent for the ultrahigh molecular weight ethylene copolymer or various wax-like substances having compatibility with the ultrahigh molecular weight ethylene copolymer can be used.

Such a solvent has a boiling point higher than the melting point of the copolymer, more preferably 20°C higher than the melting point of the copolymer.
A solvent having a boiling point higher than that is used.

Specifically, such solvents include n-nonane, n-
- Decane, n-undecane, n-dodecane, n-tetradecane, n-octadecane or liquid paraffin, aliphatic hydrocarbon solvents such as kerosene, xylene, naphthalene,
Tetralin, butylbenzene, p-cymene, cyclohexylbenzene, diethylbenzene, pentylbenzene,
Aromatic hydrocarbon solvents such as dodecylbenzene, bicyclohexyl, decalin, methylnaphthalene, ethylnaphthalene or hydrogenated derivatives thereof, 1,1,2.2-tetrachloroethane, pentachloroethane, hexachloroethane, 1.2.3- Examples include halogenated hydrocarbon solvents such as trichloropropane, dichlorobenzene, 1.2.4-trichlorobenzene, and bromobenzene, and mineral oils such as paraffinic process oils, naphthenic process oils, and aromatic process oils.

Further, as the wax as a diluent, specifically, an aliphatic hydrocarbon compound or a derivative thereof is used.

Such aliphatic hydrocarbon compounds are mainly composed of saturated aliphatic hydrocarbon compounds, and are usually compounds called paraffin waxes having a molecular weight of 2,000 or less, preferably 1,000 or less, more preferably 800 or less.

Examples of such aliphatic hydrocarbon compounds include n-alkanes having 22 or more carbon atoms such as tocosan, tricosane, tetracosane, and triacontane, mixtures of these with lower n-alkanes as main components, petroleum So-called paraffin wax purified from 100% of ethylene or low molecular weight polymers obtained by copolymerizing ethylene and other α-olefins, such as medium and low pressure polyethylene wax, high pressure polyethylene wax, ethylene copolymer wax, or Waxes obtained by reducing the molecular weight of polyethylene such as medium- and low-pressure polyethylene and high-pressure polyethylene by thermal degradation, oxides of these waxes, oxidized waxes modified with maleic acid, and waxes modified with maleic acid are used.

Examples of aliphatic hydrocarbon compound derivatives include, for example, one or more carboxyl groups, preferably one to two carboxyl groups, particularly preferably one carboxyl group, at the terminal or inside of an aliphatic hydrocarbon group (alkyl group, alkenyl group), A compound having a functional group such as a hydroxyl group, a carbamoyl group, an ester group, a meltcapto group, or a carbonyl group with a carbon number of 8 or more, preferably a carbon number of 12 to 50 or a molecule of 1130 to 2000.
Preferably, 200 to 800 fatty acids, aliphatic alcohols, fatty acid amides, fatty acid esters, aliphatic mercaptans, aliphatic aldehydes, aliphatic ketones, etc. are used.

Examples of such aliphatic hydrocarbon compound derivatives include fatty acids such as capric acid, lauric acid, myristic acid, valmitic acid, stearic acid, and oleic acid, lauric alcohol, myristyl alcohol, cetyl alcohol, and stearyl alcohol. Fatty acid amides such as caprinamide, lauramide, valmitinamide, and stearylamide, fatty acid esters such as stearyl acetate, and the like are used.

The ultra-high molecular weight ethylene/α-olefin copolymer and diluent differ depending on their type, but generally 3
=97~80:20, especially 15:85~60:
A weight ratio of 40 is used. If the diluent plate is lower than the above range, the melt viscosity will become too high, making melt kneading and melt molding difficult, and the resulting molded product will have a markedly rough surface and is likely to cause stretch breakage, etc. If the amount of the diluent is larger than the above range, melt-kneading will become difficult, and the resulting molded product will have poor stretchability.

Melt kneading is generally carried out at 150-300°C, particularly at 170-200°C.
It is carried out at a temperature of 70°C. If the temperature is lower than the above range, the melt viscosity will be too high and melt molding will be difficult, and if the temperature is higher than the above range, the molecular weight of the ultra-high molecular weight ethylene/α-olefin copolymer will decrease due to thermal degradation. death,
It becomes difficult to obtain a molded article having excellent high elastic modulus and high strength. The blending may be done by dry blending using a Henschel mixer, V-type blender, etc.
Alternatively, it may be carried out using a single screw extruder or a multi-screw extruder.

Melt molding of a dope (spinning stock solution) comprising an ultra-high molecular weight ethylene/α-olefin copolymer and a diluent is generally performed by melt extrusion molding. Specifically, filaments for drawing are obtained by melt extruding the dope through a spinneret.

At this time, the molten material extruded from the spinneret may be drafted, that is, drawn in the molten state. Extrusion speed of molten resin in the Gui orifice■. The draft ratio can be defined by the following formula:

Draft ratio -V/vo (2) This draft ratio varies depending on the temperature of the mixture, the molecular weight of the ultra-high molecular weight ethylene copolymer, etc., but is usually 3 or more, preferably 6 or more. can.

Next, the ultra-high molecular weight ethylene α obtained in this way
- Stretching the unstretched molded olefin copolymer. Stretching is carried out so as to effectively impart at least uniaxial molecular orientation to the unstretched molded article obtained from the ultra-high molecular weight ethylene/α-olefin copolymer.

Stretching of an unstretched molded article obtained from an ultra-high molecular weight ethylene/α-olefin copolymer is generally carried out at a temperature of 40 to 160°C, particularly 80 to 145°C. Air,
Either water vapor or liquid medium can be used. However, as a heat medium, a liquid medium that is a solvent capable of eluting and removing the diluent described above and whose boiling point is higher than the melting point of the molded article composition, specifically, decalin, decane, kerosene, etc., is used. It is preferable to carry out the stretching operation in such a manner that the diluent described above can be removed, uneven stretching will not occur during stretching, and a high stretching ratio can be achieved.

The means for removing the diluent from the ultra-high molecular weight ethylene/α-olefin copolymer is not limited to the above-mentioned method, but may include a method of treating an unstretched material with a solvent such as hexane, heptane, hot ethanol, chloroform, or benzene, and then stretching it; A stretched product with high elastic modulus and high strength can also be obtained by removing the diluent in the molded product by treating the stretched product with a solvent such as hexane, heptane, hot ethanol, chloroform, or benzene.

The stretching operation can be performed in one stage or in multiple stages of two or more stages. The stretching ratio depends on the desired molecular orientation and the associated effect of increasing the melting temperature, but is generally between 5 and 5.
80 times, preferably 10 to 50 times.

Generally, it is preferable to carry out the stretching operation in two or more stages, and in the -th stage, the stretching operation is carried out while extracting the diluent in the extrudate at a relatively low temperature of 80 to 120'C. In the second stage and subsequent stages, it is preferable to perform the stretching operation of the molded body at a temperature of 120 to 160 DEG C. and at a temperature higher than the stretching temperature of the first stage.

In the case of a uniaxial stretching operation, tension stretching may be performed between rollers having different circumferential speeds.

The molecularly oriented molded product thus obtained can be heat-treated under restrictive conditions if desired.

This heat treatment is generally carried out at 140-180°C, preferably at 15°C.
At a temperature of 0-175°C for 1-20 minutes, preferably 3-20 minutes.
It can be done for 10 minutes. The heat treatment further advances the crystallization of the oriented crystal parts, shifts the crystal melting temperature to a higher temperature side, improves the strength and elastic modulus, and further improves the creep resistance at high temperatures.

In the present invention, a rope is braided from such an ultra-high molecular weight polyolefin molecular oriented product or a filament-like molecularly oriented molded product of an ultra-high molecular weight ethylene/α-olefin copolymer, and then the rope is braided. f! Used as xNQ. The breaking energy of the rope constituting the fishing net is 3 kg-m/g or more, preferably 4 kg-m72 or more, similar to the fishing net traction rope described later. Further, the rope constituting the fishing net used in the present invention has excellent knot strength, and the knot strength is 30% or more, preferably 40% or more of the breaking strength.

A conventionally known method is employed to braid a rope from filament-like molecularly oriented bodies.

Generally suitable rope forms include three-strand, six-strand ropes for twisted structures, and eight-strand ropes for braided structures (commonly known as
Structures include eight ropes), 12-stroke ropes (commonly known as toer ropes), and double-braided ropes (commonly known as taffle lobes).

In addition, polyester, nylon,
Using polypropylene, a filament-like molecularly oriented molded body used in the present invention can be used as the core blade. The double blade or outer blade jacket is made of polyester, nylon, polypropylene, etc., with an intermediate layer such as neoprene or vinyl chloride in the middle.
As the parallel yarn core, a structure such as a uniline parallel yarn core using the filament-like molecularly oriented molded product of the present invention can be mentioned.

Furthermore, in the present invention, such ultra-high molecular weight ethylene α
- Braid a rope from a filament-like molecularly oriented molded product of an olefin copolymer and enjoy fishing! QUsed as a towing rope.

Furthermore, the breaking energy of the fishing rope of the present invention which is braided into a rope is 3 klr-m72 or more. It has appropriate elongation compared to molecularly oriented polyethylene, and has high knot strength, so it can be knitted in a wide variety of ways. Furthermore, it is possible to obtain the effect that there is less loss when forming the rope.

As described above, in the present invention, fishing nets and fishing net traction ropes made of molecularly oriented molded products of ultra-high molecular weight polyolefin and molecularly oriented molded products of ultra-high molecular weight ethylene/α-olefin copolymer are used. Because of this, it can be made lightweight and thin, and has excellent mechanical strength and IS resistance, as well as excellent creep resistance.

EXAMPLES The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples.

Slurry polymerization of ultra-high molecular weight ethylene-butene-1 copolymer using a Ziegler catalyst and n-decane 1.1+ as a polymerization solvent I did it. A mixed monomer gas with a molar ratio of ethylene and butene-1 of 97.2:2.35 was continuously supplied to the reactor to maintain a constant pressure of 5 kg/cd. The process was completed in 2 hours at 70°C.

The yield of the obtained ultra-high molecular weight ethylene-butene-1 copolymer powder was 160 g, and the intrinsic viscosity [η] (decalin = 13
5° C.) was 8.2 dJ/l, and the butene-1 content by infrared spectrophotometer was 1.5 carbon atoms per 100°.

Preparation of stretched and oriented ultra-high molecular weight ethylene-butene-1 copolymer powder> 20 parts by weight of the ultra-high molecular weight ethylene-butene-1 copolymer powder obtained by the above polymerization and paraffin wax (melting point -69°C, molecular weight =490) A mixture of 80 parts by weight was melt-spun under the following conditions.

3.5- as a process stabilizer to 100 parts by weight of the mixture.
Di-tert-butyl-4-hydroxytoluene 0
．． Then, the mixture was melt-kneaded using a screw extruder (screw diameter = 25+w+, L/D-25, manufactured by Thermoplastics) at a set temperature of 190°C. Subsequently, the mixed melt was melt-spun using a spinning device with an orifice diameter of 2 mm attached to the extruder. The extrusion melt is 36 mm with an air gap of 180a11
The fibers were taken up at a draft ratio of twice as high, cooled and solidified in air, and undrawn fibers were obtained. Furthermore, the undrawn fibers were drawn under the following conditions.

Two-stage stretching was carried out using three Godets rolls. At this time, the heating medium in the first stretching tank was n-decane, and the temperature was 1.
The heating medium in the second drawing tank was triethylene glycol, and the temperature was 145°C. The effective length of each tank was 50 cm.

During stretching, the rotational speed of the first godet roll is set to 0.
By changing the rotational speed of the third godet roll to 5 m/min, oriented fibers with a desired drawing ratio were obtained. The rotational speed of the second godet roll was appropriately selected within a range that allowed stable stretching. Almost all of the initially mixed paraffin wax was extracted into n-decane during stretching. Thereafter, the oriented fibers were washed with water, dried and smoked under reduced pressure at room temperature overnight, and various physical properties were measured. The stretching ratio was calculated from the rotational speed ratio of the first godet roll and the third godet roll.

Measurement of Tensile Properties> The elastic modulus and tensile strength were measured at room temperature (23°C) using a DO3-50M tensile tester manufactured by Shimadzu Corporation.

At this time, the sample length between the clamps was 100 U, and the tensile rate was 1100 n/min (100%/min strain rate). The elastic modulus was calculated using the slope of the tangent at the initial elastic modulus. The fiber cross-sectional area required for calculation was calculated from the weight, assuming the density as 0.960 g/CC.

Tensile modulus and strength retention after heat history The heat history test was conducted by leaving the sample in a car oven (manufactured by Perfect Oven Nitabai Seisakusho).

The sample had a length of about 3 m, and was folded over a stainless steel frame equipped with a plurality of pulleys at both ends to fix both ends of the sample. At this time, both ends of the sample were fixed to the extent that the sample did not sag, and no tension was actively applied to the sample. The tensile properties after thermo-M delivery were measured based on the description of the measurement of tensile properties described above.

Measurement of creep resistance〉 Creep resistance was measured using a thermal stress strain measuring device TMA/5
Using SIO (manufactured by Seiko Electronics Industries, Ltd.), sample length 1a
a, ambient temperature 70℃, load is 30% of breaking load at room temperature
% by weight under accelerated conditions. In order to quantitatively evaluate the amount of creep, the following two values were determined.

In other words, the value of creep elongation (%) CRso after 90 seconds elapsed after applying a load to the sample, and the value of 18
This is the value of the average cleave speed (sec'') ε after 0 seconds have elapsed.

Table 1 shows the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers.

The original crystal melting peak of ultra-high molecular weight ethylene-butene-1 copolymer drawn filament (Sample-1) is 126.7
℃, and the ratio of Tp to the total crystal melting peak area was 33.8%. In addition, the creep resistance is CR9o=3
．． 1%, ε=3.03Xio'sec"te.Furthermore, after a thermal history of 170°C for 15 minutes, the elastic modulus retention rate was 102.2%, and the strength retention rate was 102.5%, indicating that the performance due to thermal history was No decrease was observed.

Also, the amount of work required to break the drawn filament is 10.
3 kg-m/r, density was 0.973 g/-, dielectric constant was 2.2, dielectric loss tangent was 0.024%, and impulse voltage breakdown value was 180 KV/city.

The filaments described above were then used to braid a rope as follows. Focus multifilament and Z in 6 strokes
A rope of 3 x 12 x 6 m construction and a rope diameter of 91 ul was obtained by twisting in the following directions. The end of this rope was subjected to an 11-tack eye splice process, and the rope properties were evaluated. The evaluation was conducted using Amsler type horizontal tensile test R (Model T-7919 manufactured by Tokyo Department 81) with a sample length of 1.5 m between the ice splice terminals in a wet state and a dry state. At this time, the temperature is room temperature (
23° C.) and the tensile speed is 15 cm/min.

The results are shown in Table 2.

Polymerization of ultra-high molecular weight ethylene/octene-1 copolymer> Slurry polymerization of ethylene was carried out using a Ziegler catalyst and n-decane 1 as a polymerization solvent.

At this time, 125 ml of octene-1 as a comonomer and 4 ON ml of hydrogen for molecular weight adjustment were added all at once before starting the polymerization to start the polymerization. Ethylene gas was continuously supplied so that the reactor pressure was maintained at a constant pressure of 5 kg/ci, and the polymerization was completed in 52 hours at 70'C.

The yield of the obtained ultra-high molecular weight ethylene/octene-1 copolymer powder was 178Ir, and its intrinsic viscosity [η] (decalin, 135°C) was 10.66 dJ/r. The mer content was 0.5 per 1000 carbon atoms.

Preparation of drawn and oriented ultra-high molecular weight ethylene/octene-1 copolymer and its physical properties> A drawn and oriented fiber was prepared by the method described in Example 1. Table 3 does not show the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers.

(Hereinafter, blank) The original crystal melting peak of the ultra-high molecular weight ethylene/octene-1 copolymer drawn filament (Sample-2) is i32.
1°C, and the ratios of Tp and Tpl to the total crystal melting peak area were 97.7% and 5.0%, respectively. Creep resistance of sample-2 is CR9o=2.0%
, ε=9.50X10'5ec-1te. In addition, the elastic modulus retention after heating at 170°C for 5 minutes was 10
The strength retention rate was 8.2%, and the strength retention rate was 102.1%.

Furthermore, the work required to break sample-2 is 1.0.1 +
rm/g, density is 0.971g/-, dielectric constant is 2.2, dielectric loss tangent is 0.03]-%, and impulse voltage breakdown value is 185 KV/l1m
Met.

A lobe of the present invention was obtained by the method described in Example 1 using Sample-2. Table 4 shows the morphology and physical properties of the rope.

Shaku Watan Ultra High Molecular Weight Polyethylene (Homopolymer) Powder (Intrinsic Viscosity [η] = 7.42 dJ/r, Decalin, 135
℃) = 20 parts by weight and ノ(roughinwa soks (melting point =
69°C5 molecular weight=/190): A mixture with 80 densities was melt-spun and drawn by the method of Example 1 to obtain draw-oriented fibers. Table 5 shows the tensile properties of the multifilament obtained by bundling a plurality of drawn and oriented fibers.

Ultra-high molecular weight polyethylene drawn filament (Sample-3)
The original crystal melting peak was 135.1°C, and the ratio of TO to the total crystal melting peak area was 8.8%.

Similarly, the ratio of the high temperature surface peak Tp1 to the total crystal melting peak area was 1% or less. Creep resistance is CR
9o=11.9%, ε=1.07xlO-3sec-'
Met. Further, the elastic modulus retention rate after heat history at 170° C. for 5 minutes was 80.4%, and the strength retention rate was 78.2%. Furthermore, the amount of work required to break sample-3 is 6.8
kr-m/g, the density is 0.985/-,
The dielectric constant is 2.3, the dielectric loss tangent is 0.030%, and the impulse voltage breakdown value is 182 K V/ram
Met.

A rope of the present invention was obtained by the method described in Example 1 using Sample-3. Table 6 shows the shape and physical properties of the rope.

From the above, it is clear that Rose, which uses a molecularly oriented molded product of ultra-high molecular weight polyethylene, is excellent as a fishing net and fishing tiQ traction rope.

Furthermore, it can be seen that the rope made of a molecularly oriented molded product of ultra-high molecular weight ethylene/α-olefin copolymer is even better in terms of the energy required to break.

In addition, these lobes have excellent properties, especially when hydrated, and have high elongation, so they have excellent strength utilization when made into ropes. From these facts, it can be seen that the molecularly oriented ultrahigh molecular weight polyolefin or ultrahigh molecular weight aethylene/α-olefin copolymer according to the present invention is most suitable for fishing nets and lobes for pulling fishing nets.

Claims (1)

[Scope of Claims] 1) A fishing net made of a molecularly oriented molded article of ultra-high molecular weight polyolefin having an intrinsic viscosity [η] of at least 5 dl/g. 2) Ultra-high molecular weight ethylene α- having an intrinsic viscosity [η] of at least 5 dl/g and containing an average of 0.1 to 20 α-olefins having 3 or more carbon atoms per 1000 carbon atoms. Fishing net made of molecularly oriented olefin copolymer. 3) α-olefin is butene-1,4-methylpentene-1, hexene-1, octene-1 or decene-1
The fishing net according to claim 2. 4) The fishing net according to claim 2, wherein the content of α-olefins is on average 0.5 to 10 per 1000 carbon atoms. 5) A fishing net traction rope made of a molecularly oriented molded ultra-high molecular weight polyolefin having an intrinsic viscosity [η] of at least 5 dl/g. 6) Ultra-high molecular weight ethylene α- having an intrinsic viscosity [η] of at least 5 dl/g and containing an average of 0.1 to 20 α-olefins having 3 or more carbon atoms per 1000 carbon atoms. Fishing net traction rope made of molecularly oriented olefin copolymer. 7) α-olefin is butene-1,4-methylpentene-1, hexene-1, octene-1 or decene-1
The rope for towing a fishing net according to claim 6. 8) The fishing net towing rope according to claim 6, wherein the content of α-olefin is on average 0.5 to 10 per 1000 carbon atoms.