JPH1161556A - Monofilament - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a monofilament excellent in balance of a straight strength and a straight elongation, and flexibility, hardly causing stickiness and cheap compared with a conventional multifilament made of a high density polyethylene. SOLUTION: This monofilament comprises a copolymer of ethylene with a 3-20C α-olefin, having 0.1-10 g/10 min MFR and 895-940 kg/m<3> density (d), satisfying the formula Tm<0.4×d-245 in which Tm is the temperature at the maximum peak position in an endothermic curve measured by a DSC, having <=2.5 wt.% proportion of an n-decane-soluble component at a room temperature, satisfying the formula FI<200×MFR between a fluidity index [FI (1/sec)] and the MFR (g/10 min), and the monofilament of ethylene-α-olefin copolymer obtained by melt spinning the copolymer has 5.0-9.0 g/d straight strength, 10-30% straight elongation and 1.0-3.0 GPa modulus at 3% elongation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a monofilament, and more particularly to a monofilament used for sports nets, woven fabrics, fishing nets, ropes, etc., which is excellent in balance and flexibility between linear strength and linear elongation. And a non-sticky monofilament.

[0002]

BACKGROUND OF THE INVENTION Sports nets, woven fabrics,
High-density polyethylene monofilaments are used for fishing nets, ropes, and the like, but the applications of these monofilaments have been limited due to insufficient flexibility.

In order to improve this flexibility, multifilaments made of high-density polyethylene composed of fine denier filaments have been put to practical use. However, the multifilament is expensive because a special molding device is required for its production.

Attempts have also been made to make monofilaments using low-density polyethylene which is excellent in flexibility. However, this monofilament has problems that the balance between the linear strength and the linear elongation is not sufficient, and that the monofilament has stickiness due to a large amount of low molecular weight components.

[0005] Therefore, it is desired to develop a monofilament which is excellent in balance and flexibility between linear strength and linear elongation and free from stickiness.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a monofilament which is excellent in balance between linear strength and linear elongation and flexibility and has no stickiness. It is intended to be.

[0007]

SUMMARY OF THE INVENTION The monofilament according to the present invention is a monofilament comprising an ethylene / α-olefin copolymer (A), wherein the ethylene / α-olefin copolymer (A) comprises (i) ethylene and carbon Α with 3-20 atoms
-It is a copolymer with olefin and (ii) melt flow rate (MFR; ASTM D 1238, 190 ° C, 2.16kg load)
Is in the range of 0.1 to 10 g / 10 min, (iii) the density (d) is in the range of 895 to 940 kg / m ³ ,
v) Temperature at the maximum peak position in the endothermic curve measured by a differential scanning calorimeter (DSC) (melting point; Tm (° C))
And the density (d (kg / m ³ )) satisfy the relationship represented by Tm <0.4 × d−245, and (v) the amount of n-decane soluble component at room temperature (W) is 2 0.5% by weight or less; (v
i) The shear stress of the molten polymer at 190 ° C. is 2.4
The fluidity index (FI (1 / second)) defined by the shear rate when reaching 10 ⁶ dyne / cm ² and the melt flow rate (MFR (g / 10 minutes)) are FI <200 × (Vii) spun ethylene • α satisfying the relationship indicated by MFR
-The linear strength of the monofilament of the olefin copolymer (A) is in the range of 5.0 to 9.0 g / d, the linear elongation is in the range of 10 to 30%, and the 3% elastic modulus is 1. 0
Ｇ3.0 GPa.

The ethylene / α-olefin copolymer (A) is preferably an ethylene / α-olefin copolymer prepared using a metallocene catalyst.

[0009]

DETAILED DESCRIPTION OF THE INVENTION Hereinafter, the monofilament according to the present invention will be specifically described. The monofilament according to the present invention is an ethylene / α-olefin copolymer (A)
Consists of

Ethylene / α-olefin copolymer (A) The ethylene / α-olefin copolymer (A) used as the material of the monofilament according to the present invention comprises ethylene and an α-olefin having 3 to 20 carbon atoms. And a copolymer of

Examples of the α-olefin having 3 to 20 carbon atoms used for copolymerization with ethylene include propylene, 1-butene, 1-pentene, 4-methyl-1-pentene and 1-hexene , 1-octene, 1-decene, 1-dodecene and the like. Among them, those having 3 to 10 carbon atoms
Α-olefins, especially α-olefins having 4 to 8 carbon atoms, are preferred.

The α-olefin as described above is used alone,
Alternatively, two or more kinds can be used in combination. In the ethylene / α-olefin copolymer (A), the molar ratio of the structural unit derived from ethylene to the structural unit derived from α-olefin having 3 to 20 carbon atoms (α-olefin / ethylene) is 0. 0.005 to 0.20, preferably 0.01 to 0.15.

The ethylene / α-olefin copolymer (A) has a melt flow rate (MFR; ASTM D 1238,1).
(90 ° C., 2.16 kg load) is preferably in the range of 0.1 to 10 g / 10 min, particularly 0.2 to 5.0 g / 10 min.
Minutes. When the melt flow rate of the ethylene / α-olefin copolymer (A) is within the above range, extrusion of a monofilament is easy.

[0014] The density of the ethylene · alpha-olefin copolymer (A) (d) is in the range of 895~940kg / m ^3, it is particularly preferably from 900~930kg / m ^3. When the density (d) of the ethylene / α-olefin copolymer (A) is within the above range, a monofilament excellent in flexibility can be obtained.

The density is 2.16 k at 190 ° C.
The strand obtained at the time of measuring the melt flow rate (MFR) under a g load is heat-treated at 120 ° C. for 1 hour, gradually cooled to room temperature over 1 hour, and then measured with a density gradient tube.

Further, the ethylene / α-olefin copolymer (A) has a temperature (melting point; maximum melting point) in an endothermic curve measured by a differential scanning calorimeter (DSC).
Tm (° C.)) and density (d (kg / m ³ )) preferably satisfy the relationship expressed by Tm <0.4 × d-245, preferably Tm <0.45 × d-292. .

The maximum peak position temperature (Tm) in an endothermic curve measured by a differential scanning calorimeter (DSC)
(° C)) is about 10 mg of a sample packed in an aluminum pan.
The temperature is raised to 200 ° C./min., Held at 200 ° C. for 5 minutes, then lowered to room temperature at 10 ° C./min., And then determined by an endothermic curve when the temperature is increased at 10 ° C./min. The measurement was performed using a DSC-7 type device manufactured by PerkinElmer.

Further, the ethylene / α-
The olefin copolymer (A) has an n-decane-soluble component content ratio (W) at room temperature of 2.5% by weight or less, preferably 2.
It is desirably 0% by weight or less. If this n-decane soluble component content ratio (W) exceeds 2.5% by weight, the stickiness of the monofilament surface becomes remarkable.

N-decane soluble component content ratio at room temperature (W)
Is a sample (ethylene / α-olefin copolymer) about 3m
g was added to 450 ml of n-decane and dissolved at 145 ° C., and the solution was cooled to 23 ° C. (room temperature), and then filtered to remove the n-decane-insoluble portion in the filtrate. It is determined by collecting the melted part, dividing the weight of the n-decane soluble part by the weight of the original sample, and multiplying the obtained value by 100.

Further, the ethylene / α-
The olefin copolymer (A) has a content of 190
The fluidity index (FI (1 / sec)) defined by the shear rate at which the shear stress at 2.4 ° C. reaches 2.4 × 10 ⁶ dyne / cm ² , and the melt flow rate (MFR)
(G / 10 minutes)) and the relationship represented by FI <200 × MFR is satisfied, and preferably, FI <1.
It is desirable that the relationship represented by 50 × MFR is satisfied. When the ethylene / α-olefin copolymer (A) having a fluidity index satisfying the above relationship is used, the monofilament having a high linear strength or a low linear elongation and an excellent balance between the linear strength and the linear elongation is obtained. Is obtained.

Fluidity index (FI (1 / sec))
Indicates that the shear stress at 190 ° C. is 2.4 × 10 ⁶ dyne /
It is determined by extruding the sample from the capillary while varying the shear rate when reaching cm ² and measuring the rate corresponding to a given stress. That is, using a capillary flow characteristic tester manufactured by Toyo Seiki Seisaku-sho, Ltd.
90 ° C, shear stress range is 5 × 10 ^{4 to} 3 × 10 ⁶ dyne
/ Cm ² . The MF of the sample to be measured
The nozzle diameter is changed as follows according to R (g / 10 minutes) and measured.

When 10 ≧ MFR> 3 1.0 mm When 3 ≧ MFR> 0.8 2.0 mm When 0.8 ≧ MFR ≧ 0.1 3.0 mm Both ethylene and α-olefin used in the present invention When a monofilament is molded from the polymer (A), the monofilament has a linear strength (JIS L 1070) of 5.0 to 9.0 g / d, preferably 5.5 to 9.0 g / d.
d, and the linear elongation (JIS L 1070) is 1
The elastic modulus is in the range of 0 to 30%, preferably 15 to 30%, and the 3% elastic modulus is in the range of 1.0 to 3.0 GPa, preferably 1.0 to 2.5 GPa.

Ethylene α-having the above-mentioned properties
The olefin copolymer (A) is produced, for example, using a so-called metallocene-based catalyst comprising a metallocene compound of a transition metal, an organic aluminum oxy compound and, if necessary, an organic aluminum compound and / or an organic boron compound. Can be.

An example of such a production method is as follows. In the presence of bis (n-butylcyclopentadienyl) zirconium dichloride and aluminoxane, ethylene is reacted with an α-olefin having 3 to 20 carbon atoms. By polymerizing, an ethylene / α-olefin copolymer (A) can be obtained.

The metallocene catalyst is usually a metallocene catalyst component (a) comprising a transition metal compound of Group IVB of the Periodic Table having at least one ligand having a cyclopentadienyl skeleton, and an organic aluminum oxy compound. A catalyst component (b), if necessary, a particulate carrier (c),
It is formed from an organoaluminum compound catalyst component (d) and an ionized ionic compound catalyst component (e).

The metallocene catalyst component (a) preferably used in the present invention is a transition metal compound of Group IVB of the periodic table having at least one ligand having a cyclopentadienyl skeleton. Examples of such a transition metal compound include a transition metal compound represented by the following general formula [I].

ML ¹ _x ... [I] In the formula, x is the valence of the transition metal atom M. M is a transition metal atom selected from Group IVB of the periodic table, and zirconium is preferable.

L ¹ is a ligand that coordinates to the transition metal atom M, and at least one of these ligands L ¹
Is a ligand having a cyclopentadienyl skeleton.
When the compound represented by the general formula [I] contains two or more groups having a cyclopentadienyl skeleton, two of the groups having a cyclopentadienyl skeleton are
They may be bonded via a (substituted) alkylene group or a (substituted) silylene group.

The ligand L ¹ other than the ligand having a cyclopentadienyl skeleton is an alkyl group, a cycloalkyl group,
An aryl group, an aralkyl group, an alkoxy group, an aryloxy group, a trialkylsilyl group, a sulfonato group-containing hydrocarbon group, a halogen atom or a hydrogen atom.

Examples of the metallocene catalyst component (a) include bis (n-butylcyclopentadienyl)
Zirconium dichloride and the like can be mentioned. As the organoaluminum oxy compound catalyst component (b), conventionally known aluminoxane is preferably used.

The particulate carrier (c) is a conventionally known inorganic or organic compound having a particle size of preferably 2
It is a granular or particulate solid having a particle size of 0 to 200 μm.
As the organoaluminum compound catalyst component (d), trialkylaluminum, alkenylaluminum, dialkylaluminum halide, alkylaluminum sesquihalide and the like are used.

As the ionized ionic compound catalyst component (e), a Lewis acid; an ionic compound such as triphenylcarbenium tetrakis (pentafluorophenyl) borate; and a carborane compound such as dodecaborane are used.

The ethylene / α-olefin copolymer (A) used in the present invention can be prepared in the presence of the above-mentioned catalyst containing the metallocene catalyst component (a) in the presence of a gas phase, a slurry or a solution. Under various conditions in the phase, ethylene and α
-It can be obtained by copolymerizing with an olefin.

In the slurry polymerization method or the solution polymerization method, an inert hydrocarbon may be used as a solvent, or an olefin itself may be used as a solvent. In the present invention, in the preparation of the ethylene / α-olefin copolymer (A), if necessary, (1) multistage polymerization, (2) multistage polymerization of a liquid phase and a gas phase, or (3) a liquid phase For example, performing polymerization in the gas phase after preliminarily polymerizing the above.

As long as the blend of two or more ethylene / α-olefin copolymers (A) satisfies all of the above physical properties (i) to (vii) of the ethylene / α-olefin copolymer (A) In the above, the monofilament according to the present invention can be prepared using this blend.

Other Components In the present invention, ethylene homopolymer, heat stabilizer, weather stabilizer, pigment, filler, etc. are contained in the ethylene / α-olefin copolymer (A) as long as the object of the present invention is not impaired. Known additives such as an agent, a lubricant, an antistatic agent, a flame retardant, and a foaming agent can be blended.

Monofilament The monofilament according to the present invention employs a so-called melt-spinning method to obtain an ethylene / α-olefin copolymer (A).
Is melted, spun and stretched. The temperature of the molten resin is usually 230 to 300 ° C., and the stretching ratio is usually 5 to 11 times, preferably 6 to 10 times. If necessary, further annealing treatment can be performed.

The fineness of the monofilament according to the present invention obtained as described above depends on its use.
Desirably, it is ６０60,000 denier, preferably 20〜１０10000 denier.

The monofilament according to the present invention is usually
Although it has a circular (round) cross-sectional shape, the cross-sectional shape can be an irregular shape other than a circle, such as a rectangle, an ellipse, or a star, depending on the purpose of use.

Further, the monofilament according to the present invention comprises:
A continuous yarn in which 2 to 10 monofilaments are connected in the horizontal direction may be used. For the continuous yarn, for example, 0.05-
It can be manufactured by extruding the resin using a die in which 2 to 10 dies are arranged in a horizontal direction at intervals of 0.20 mm.

[0041]

According to the present invention, a monofilament having excellent balance between linear strength and linear elongation and flexibility and having no stickiness is obtained by using an ethylene / α-olefin copolymer having specific physical properties. Can be provided. Since this monofilament does not require a special molding device for molding, it is less expensive than a conventional high-density polyethylene multifilament.

The monofilament according to the present invention having the above excellent physical properties is suitable for applications such as sports nets, woven fabrics, knits, fishing nets and ropes.

[0043]

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

[0044]

EXAMPLE 1 An ethylene / 1-hexene copolymer (1-hexene content: 1-hexene content:
3.2 mol%) using a 40 mmφ monofilament molding machine (L / D = 24) manufactured by Uniplus Co., Ltd., nozzle diameter 1.0 mmφ, die temperature 270 ° C., air gap 50
A monofilament having a fineness of 400 denier was obtained under the conditions of mm, a stretching tank of 100 ° C., a take-up speed of 120 m / min, and a stretching magnification of 9 times.

About the obtained monofilament, JI
According to SL 1070, a tensile test was performed under the conditions of a grip interval of 300 mm and a tensile speed of 300 mm / min, and the linear strength and the linear elongation were measured. Further, a 3% elastic modulus, which is a ratio between a tensile load and an elongation at the time of 3% deformation, was obtained, and this elastic modulus was used as an index of flexibility.

The results are shown in Table 1.

[0047]

Example 2 A monofilament was formed in the same manner as in Example 1 except that an ethylene / 1-hexene copolymer having a 1-hexene content of 3.7 mol% was used to obtain a monofilament having a fineness of 400 denier. Was.

The linear strength, linear elongation and 3% elastic modulus of the obtained monofilament were measured by the above-mentioned test methods. The results are shown in Table 1.

[0049]

Example 3 A monofilament was formed in the same manner as in Example 1 except that an ethylene / 1-hexene copolymer having a 1-hexene content of 3.0 mol% was used to obtain a monofilament having a fineness of 400 denier. Was.

The linear strength, linear elongation and 3% elastic modulus of the obtained monofilament were measured by the above-mentioned test methods. The results are shown in Table 1.

[0051]

Comparative Example 1 Instead of the ethylene / 1-hexene copolymer of Example 1, an ethylene / propylene copolymer having the characteristics shown in Comparative Example 1 in Table 1 (propylene content:
Monofilament was formed in the same manner as in Example 1 except that 0.9 mol%) was used to obtain a monofilament having a fineness of 400 denier.

The linear strength, linear elongation and 3% elastic modulus of the obtained monofilament were measured by the above test methods. The results are shown in Table 1.

[0053]

[Table 1]

Claims (5)

[Claims] 1. An ethylene / α-olefin copolymer (A)
Wherein the ethylene / α-olefin copolymer (A) is (i)
A copolymer of ethylene and an α-olefin having 3 to 20 carbon atoms, and (ii) a melt flow rate (MFR;
ASTM D 1238, 190 ° C, 2.16 kg load) in the range of 0.1 to 10 g / 10 min, (iii) density (d) in the range of 895 to 940 kg / m ³ ,
v) Temperature at the maximum peak position in the endothermic curve measured by a differential scanning calorimeter (DSC) (melting point; Tm (° C))
And the density (d (kg / m ³ )) satisfy the relationship represented by Tm <0.4 × d−245, and (v) the amount of n-decane soluble component at room temperature (W) is 2 0.5% by weight or less; (v
i) The shear stress of the molten polymer at 190 ° C. is 2.4
The fluidity index (FI (1 / second)) defined by the shear rate when reaching 10 ⁶ dyne / cm ² and the melt flow rate (MFR (g / 10 minutes)) are FI <200 × (Vii) spun ethylene • α satisfying the relationship indicated by MFR
-The linear strength of the monofilament of the olefin copolymer (A) is in the range of 5.0 to 9.0 g / d, the linear elongation is in the range of 10 to 30%, and the 3% elastic modulus is 1. 0
A monofilament characterized by being in the range of -3.0 GPa. 2. The monofilament according to claim 1, wherein the ethylene / α-olefin copolymer (A) is an ethylene / α-olefin copolymer prepared using a metallocene catalyst. . 3. The monofilament has a fineness of 10 to 60.
3. The method according to claim 1, wherein said denier is 00 denier.
2. The monofilament according to 1. 4. The monofilament according to claim 1, wherein said monofilament has an irregular cross-sectional shape. 5. The monofilament according to claim 1, wherein the monofilament is a continuous yarn.