KR102264017B1 - High-strength spun yarn having improved cut resistance - Google Patents

Abstract

The present invention is a high-strength spun yarn formed of a polyethylene resin and comprising a polyethylene fiber whose main repeating unit is ethylene, wherein the polyethylene fiber has a melt index of 0.6 to 2 g/10 min, and a molecular weight distribution index of 5 to 10 It relates to a high-strength spun yarn with improved cut resistance formed of a polyethylene resin, wherein the polyethylene fiber has a crystallinity of 75% or more and a crystal size of 10 Å or more.

Description

High-strength spun yarn with improved cut resistance {HIGH-STRENGTH SPUN YARN HAVING IMPROVED CUT RESISTANCE}

The present invention relates to high-strength spun yarn with improved cut resistance, and more particularly, to high-strength spun yarn with improved cut resistance by using high-strength polyethylene multifilaments.

In various industrial fields, certain materials, raw materials or parts are cut so that they can be used, and in these industries, work clothes with cut resistance are required to protect workers from being cut for the safety of workers.

Examples of spun yarns suitable for this purpose are fibers made of aramid, high strength polyethylene or polybenzoxazole.

In particular, high-strength polyethylene resins are inexpensive and have excellent chemical resistance and product processability, so their use is increasing for engineering plastics, films, fibers and non-woven fabrics. In the textile field, monofilaments and multifilaments are manufactured and used for clothing, Its use is expanding for industrial purposes. In particular, according to the latest fiber trends, interest in high-functional polyethylene fibers requiring high strength and high modulus of elasticity is increasing.

In US Patent No. 4,228,118, a polyethylene resin having a number average molecular weight of 20,000 or more and a weight average molecular weight of 125,000 or less is melted at a spinning temperature of 220 to 335° C. After winding at a temperature of 200 to 335° C. at a minimum spinning speed of 30 m/min, it was stretched 20 times or more to prepare a fiber of 10 to 20 g/d. However, this method has limitations in production due to the low number of nozzles and the spinning speed according to the spin draw method in the commercial production of polyethylene fibers, and produces polyethylene fibers with excellent uniformity and spinning workability when producing tens to hundreds of multifilaments. have difficulty doing

In addition, in Korean Patent Registration No. 0909559, the weight average molecular weight is 300,000 or less, the ratio of the weight average molecular weight to the number average molecular weight (Mw/Mn), which is a molecular weight distribution index, is 4.0 or less, and high strength polyethylene fibers that express high strength are specified. are doing However, it is difficult to control the molecular weight distribution index of the raw material to 4.0 or less, and since the molecular weight distribution index is formed low, high stretching of 10 times or more is required to express high strength, so there is a problem in that spinning workability and fairness are lowered.

In general, high-strength polyethylene fibers have excellent cutting resistance and are widely used as industrial products such as industrial safety gloves. However, the cutting resistance of conventional high-strength polyethylene fibers is expressed only by the strength of polyethylene fibers. If the strength is not uniform or the strength is weakened in a specific part, there is a problem that the cutting resistance may be reduced.

In addition, in order to further increase the cut resistance, a single spun yarn made of staple fibers and a composite yarn containing one or more metal wires have been proposed. It cannot be improved.

In addition, work clothes used in industrial sites must be worn for a fairly long period of time, so they must be excellent in wearability,

In the case of the conventional UHMWPE fiber, the elongation was low, and even when it was made of spun yarn, the feel was stiff, so the fit was not excellent, and it was difficult for the user to wear it for a long time.

The present invention was invented to solve the problems of the prior art as described above, and an object of the present invention is to provide a spun yarn with improved cut resistance by utilizing a high strength polyethylene fiber having improved cut resistance.

Another object of the present invention is to provide a spun yarn with improved cut resistance by controlling the crystallinity and crystal size of polyethylene fibers.

The present invention is a high-strength spun yarn formed of a polyethylene resin and comprising a polyethylene fiber whose main repeating unit is ethylene, wherein the polyethylene fiber has a melt index of 0.6 to 2 g/10 min, and a molecular weight distribution index of 5 to 10 Provided is a high-strength spun yarn with improved cut resistance, characterized in that the polyethylene fiber has a crystallinity of 75% or more and a crystal size of 10 Å or more.

In addition, there is provided a high-strength spun yarn with improved cut resistance, characterized in that the polyethylene fiber has a strength of 12 to 16 g/d.

In addition, the polyethylene fiber, a melt index of 0.6 to 2 g / 10 min, a spinning step of melt-spinning a polyethylene resin having a molecular weight distribution index of 5 to 10 at 230 ~ 290 ℃ to form an undrawn yarn; a stretching step of stretching the undrawn yarn; And, it provides a high-strength spun yarn with improved cut resistance, characterized in that it is prepared including an aging step of aging the drawn polyethylene fiber at 90 ~ 130 ℃.

In addition, the spinning speed in the spinning step provides a high-strength spun yarn with improved cut resistance, characterized in that 120 ~ 160mpm.

In addition, the aging step provides a high-strength spun yarn with improved cut resistance, characterized in that aging for 5 to 20 seconds.

In addition, the manufacturing method is a high-strength spun yarn with improved cut resistance, characterized in that it satisfies the following formula (1).

Equation (1) 210≤S+T≤290

However, S is an integer of the spinning speed (mpm) of the spinning step, and T is an integer of the aging temperature (℃) of the aging step.

In addition, the polyethylene fiber provides a high-strength spun yarn with improved cut resistance, characterized in that the fiber length is 20 to 100 mm.

In addition, the high-strength spun yarn with improved cut resistance provides a high-strength spun yarn with improved cut resistance, characterized in that the number of counts is 10 to 50.

In addition, there is provided an article comprising the above high-strength spun yarn.

In addition, the article provides an article characterized in that the level (Level) according to the cut resistance standard is 3 or more.

In addition, the article provides an article characterized in that the cutting force is 5.0N or more.

The high-strength spun yarn with improved cut resistance according to the present invention has the effect of improving the cut resistance of the high-strength spun yarn by containing polyethylene fibers with improved cut resistance by controlling the crystallinity and crystal size of the polyethylene resin.

In addition, the polyethylene fiber has a high degree of crystallinity and excellent elongation, so that the high-strength spun yarn of the present invention has excellent cooling properties and improved wearability when manufacturing clothes.

1 is a process diagram showing a method of manufacturing a high-strength polyethylene fiber according to the present invention.
Figure 2 is a view briefly showing the aging step of the high-strength polyethylene fiber manufacturing process according to the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. First, it should be noted that in the drawings, the same components or parts are denoted by the same reference numerals whenever possible. In describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially' and the like are used in or close to the numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and provide an understanding of the present invention. To help, precise or absolute figures are used to prevent unfair use by unscrupulous infringers of the stated disclosure.

1 is a process chart showing a method of manufacturing high-strength polyethylene fibers according to the present invention, and FIG. 2 is a diagram schematically showing the aging step in the high-strength polyethylene fiber manufacturing process according to the present invention.

The present invention relates to a high-strength spun yarn formed of a polyethylene resin and having improved cut resistance comprising polyethylene fibers whose main repeating unit is ethylene.

The polyethylene fiber has a melt index of 0.6 to 2 g/10 min, and is formed of a polyethylene resin having a molecular weight distribution index of 5 to 10, so that the polyethylene fiber has a crystallinity of 75% or more and a crystal size of 10 Å or more.

The present invention is an invention for improving the cut resistance of high-strength polyethylene fibers by controlling the degree of crystallinity and crystal size. Although the factors for expressing the cutting resistance have not been specifically identified, the paper J. Polym. Sci. Part B Polym. Phys., vol. 48, pp.1861-1872 (2010), Paper Mater. Sci. Eng. A, vol. Referring to Fibril Formation and Fracture Mechanism of crystallization of polyethylene in 500, 216-224 (2009), slippage of surface crystals from the point at which crystals are maximized as polyethylene multifilaments are stretched to express mechanical strength. Therefore, it can be estimated that the cut resistance is expressed.

The cut resistance measurement method is defined by calculating the number of repetitions when repeatedly cutting a woven or knitted fabric made of polyethylene by applying a constant load to a sharp circular blade, or a woven or knitted fabric made of polyethylene to a certain length by a straight blade. It can be defined as the load to be cut, and in the present invention, only the polyethylene fiber having a certain strength or more having a certain strength or more occurs crystal slippage due to an external force on the fiber surface by the blade when cutting, resulting in cut resistance It is estimated that , and it can be seen that there is a certain relationship between the degree of crystallinity and the crystal size on the cutting resistance.

The polyethylene fiber of the present invention preferably has a crystallinity of 75% or more and a crystal size of 10 Å or more, and it is more preferable that the crystallinity is 80% or more and a crystal size of 12 Å or more.

The polyethylene resin forming the high-strength polyethylene fiber of the present invention has a melt index of 0.6 to 2.0 g/10 min, preferably 0.8 to 1.4 g/10 min.

If the melt index is less than 0.6 g/10 min, the flowability of the melt of polyethylene resin in the extruder is not good, so that the spinning speed cannot be increased, and there may be problems that act as a cause of the nozzle surface during spinning. In addition, when the melt index exceeds 2.0 g/10 min, spinning workability is excellent, but flowability is not suitable at an appropriate spinning temperature, so it may be difficult to obtain high-strength polyethylene fibers after stretching.

In addition, the polyethylene resin used in the present invention may preferably have a weight average molecular weight (Mw) of 100,000 to 300,000, and a molecular weight distribution index (weight average molecular weight/number average molecular weight, Mw/Mn) of 5 to 10.

When the weight average molecular weight (Mw) is less than 100,000, spinning workability is improved during spinning, but there is a limit to expressing high strength, and when it exceeds 300,000, it affects the flowability of the resin inside the extruder during melt spinning, so that the spinning uniformity and Workability may be adversely affected.

When the molecular weight distribution index is less than 5, high magnification stretching of 10 times or more is required to express high strength, and the defects of the hair or the stretching roller are increased accordingly, so that the quality may be deteriorated as the number of stretching trimmings increases. In addition, when the molecular weight distribution index exceeds 10, a smooth stretching process cannot be performed because a large number of high molecular weight polyethylene and low molecular weight polyethylene are mixed in the polyethylene resin, and thus there is a limitation in expressing high strength.

As described above, the high-strength polyethylene fiber with improved cut resistance of the present invention is manufactured including a spinning step 100 , a stretching step 200 , and an aging step 300 as shown in FIG. 1 .

The high-strength polyethylene fiber with improved cut resistance of the present invention controls the crystallinity and crystal size of the polyethylene fiber through the spinning speed in the spinning step 100 and the aging step 300 carried out at a high temperature after stretching.

The spinning step 100 is a step of forming an undrawn yarn by performing the melt spinning. The polyethylene resin having the molecular weight distribution index and the melt index controlled is melted in an extruder, and an undrawn yarn can be prepared by installing a nozzle hot tube.

In controlling the crystallinity and crystal size of the polyethylene fiber, the spinning temperature in the spinning step is preferably 230 ~ 290 ℃, the spinning speed will preferably be 120 ~ 160mpm.

When spinning, the spinning nozzle having 60 to 400 holes can be used to manufacture high-strength polyethylene fibers with improved cut resistance of the present invention.

If the spinning speed is less than 120mpm in the spinning step, the manufacturing processability of the undrawn yarn is improved, but the stretchability is lowered in the drawing step, so it is difficult to control the fineness, and hair or loops of the fiber may occur.

In addition, if the spinning speed exceeds 160 mpm in the spinning step, the possibility of thread trimming on the nozzle face or the occurrence of thread trimming during cooling may increase, thereby reducing fairness. Therefore, it is preferable that the spinning speed be 120 to 160 mpm.

The spinning temperature and spinning speed are closely related to the orientation of high-strength polyethylene fibers, and in the case of polyethylene fibers with good fiber orientation, fairness during drawing is advantageous.

The stretching step 200 is a step of stretching the undrawn yarn prepared in the spinning step. The stretching step may be performed using a multi-stage stretching roller, and it is preferable to stretch in two or three stages at 60 to 120 ° C. will be.

In the drawing step, the overall draw ratio (DR) is preferably 6 to 10. If the overall draw ratio (DR) is lower than 6, the strength of the polyethylene fiber is lowered, and if it is higher than 10, the quality of the polyethylene fiber is severe due to the occurrence of yarn breakage during drawing. may be lowered.

The aging (Aging) step 300 is a step of aging (aging) the stretched polyethylene fibers by staying at 90 ~ 130 ℃.

In the aging step 300 , as shown in FIG. 2 , the polyethylene fiber drawn at a predetermined temperature may be aged using a plurality of aging rollers 330 in the heating chamber 310 .

The aging step does not use a heating roller that directly transfers heat to the roller in order to prevent defects of fibers due to the roller having a high temperature, and performs the aging step in a non-contact type using a heating chamber as in FIG. it would be preferable

3, when the aging step 300 is carried out through the heating chamber, the polyethylene fiber may sag due to the aging temperature in the heating chamber maintained at a constant high temperature on the roller surface. , it would be preferable to control a constant tension in the second guide rollers 210 and 230 and the tension roller 250 .

The heating chamber 310 maintains a constant heat received by the polyethylene fiber by controlling the ambient temperature in the chamber rather than the heating roller method.

Since the high-strength polyethylene fiber of the present invention has a fast crystallization rate and can form crystals in a short time and increase the crystal size, it is preferable to control the crystal aging time to pass through a plurality of aging rollers 330 .

The aging temperature is preferably in the range of 90 to 130 ℃, it will be preferable to control the speed of the roller with a draw ratio of 0.98 to 1.02.

If the aging temperature is less than 90 ℃, the tension in the aging roller 330 may increase and the fiber may be cut, thereby reducing fairness. If the aging temperature exceeds 130 ℃, the fibers may be fused to the roller surface or non-uniform. As a result, the physical properties of the polyethylene fiber may be reduced, and defects such as wool or loops may occur.

The aging step is preferably 5 to 20 seconds. When the aging time is less than 5 seconds, control over crystallinity and crystal size may be insignificant, and if it is 20 seconds or more, the polyethylene fiber is relaxed and the physical properties may be reduced.

The high-strength polyethylene fiber that has undergone the aging step 300 may be wound through a variable guide roller 410 .

As described above, in the high-strength polyethylene fiber with improved cut resistance according to the present invention, the degree of crystallinity and crystal size are controlled through the spinning speed in the spinning step and the aging temperature in the aging step. It would be desirable to satisfy (1).

Equation (1) 210≤S+T≤290

However, S is an integer of the spinning speed (mpm) of the spinning step, and T is an integer of the aging temperature (℃) of the aging step.

If the S+T is less than 210 or exceeds 290, the crystallinity and crystal size may be lowered, thereby reducing the effect of improving the cutting resistance.

The high-strength polyethylene fiber with improved cut resistance according to the present invention, which is manufactured including the spinning step 100, the stretching step 200, and the aging step 300 as described above, has the spinning step, the drawing step, and the aging step successively. It may be carried out as a one-step process, or it may be manufactured as a two-step process in which a stretching step and an aging step are continuously performed after the spinning step of manufacturing an undrawn yarn.

The polyethylene fiber of the present invention prepared as described above is manufactured as a multifilament, and is manufactured into a tow by rewinding, and then manufactured as a short fiber by a cutting process to be manufactured as a spun yarn.

The short fibers made of the polyethylene fibers can be adjusted in fiber length depending on the purpose of the spun yarn, but it is generally preferable to prepare short fibers having a fiber length of 20 to 100 mm to prepare the spun yarn.

The high-strength polyethylene spun yarn can be manufactured by a general spun yarn manufacturing method, and it may be manufactured by honta, somen/refined, soft, roving, and spinning processes.

The high-strength polyethylene spun yarn is preferably formed in 10 to 50 numbers, and when the high-strength polyethylene spun yarn is manufactured to exceed 50 numbers, the spun yarn thickness becomes thinner and the knitted fabric is excellent in wearing comfort, but the slip of short fibers during the softening process during the spun yarn process Due to the severe occurrence, each monofineness may become non-uniform, and strength and cutting resistance may become non-uniform, and fairness due to slip may be reduced. In addition, when the number of spun yarns is less than 10, the strength may be improved, but as the thickness of the spun yarns increases, the wearer's wearing comfort may be lowered.

The high-strength polyethylene fiber of the present invention exhibits high strength of 12 g/d or more, and has a crystallinity and crystallization size capable of expressing cut resistance, so that the spun yarn made of the high-strength polyethylene fiber can express cut resistance.

When the high-strength polyethylene fiber was less than 12 g/d, it was confirmed that the cut resistance was similarly lowered in the spun yarn, and even when the crystallinity was less than 75%, the cut resistance was lowered. This is thought to be possible because the polyethylene fiber constituting the spun yarn exhibits high strength, and the crystallinity and crystal size are within the range for maximizing the cutting resistance.

In addition, the high-strength polyethylene fiber of the present invention is highly oriented through multi-stage stretching at high magnification, so it has excellent surface lubricity and excellent tactile feel. Wearability is improved.

After the high-strength polyethylene fiber is manufactured, post-processing such as crimping and heat setting may be performed on the polyethylene fiber to improve the physical properties and wearability of the spun yarn before cutting into short fibers.

The high-strength polyethylene spun yarn with improved cut resistance according to the present invention prepared as described above has excellent cut resistance and has a cut resistance index of 7 or more when manufactured as a woven or knitted fabric. ) 3 or more and a cutting resistance of 5N or more can be manufactured.

The high strength polyethylene spun yarn with improved cut resistance may also be used in a wide variety of other types of articles.

Non-limiting examples include, for example, insulating materials for refrigeration units (eg, refrigerators, freezers, vending machines, etc.); automotive parts (eg front or rear seats, headrests, armrests, donor panels, rear shelf/package tray, steering wheel and interior trim, dashboard, etc.); building panels and components (eg roofs, wall cavities, underfloors, etc.); clothing (eg coats, shirts, pants, gloves, aprons, work clothes, shoes, boots, hats, sock liners, etc.); furniture and bedding (eg sleeping bags, duvets, etc.); fluid storage/transfer systems (eg, pipes or tanks of liquid/gas hydrocarbons, liquid nitrogen, oxygen, hydrogen, or crude oil); extreme environments (eg, underwater or in space); food and beverage products (eg cups, cup holders, plates, etc.); containers and bottles; etc.

In addition, high strength polyethylene fibers may be used in "garment", which is meant to include any article that has a shape that is generally tailored to a part of the body. Examples of such articles include, but are not limited to, apparel (eg, shirts, pants, jeans, slacks, skirts, coats, activewear, athletic wear, aerobics, and gym clothes, swimwear, cycling jerseys or shorts, swimwear/bathing suits) suit), lace suits, sweat suits, body suits, etc.); footwear (eg, shoes, socks, boots, etc.); Protective clothing (e.g. firefighter coats), clothing accessories (e.g. belts, bra straps, side panels, gloves, socks, leggings, orthopedic braces, etc.), underwear (e.g. underwear, t-shirts, etc.), compression garments, and draping clothing (eg, kilt loincloth, toga, poncho, cape, shawl, etc.).

Hereinafter, a high-strength polyethylene spun yarn with improved cut resistance was prepared as an example according to the present invention. The present invention is not limited to these examples.

Example 1 to 6, comparative example 1 to 4

Polyethylene resin having a melt index of 1.0 g/10min, a molecular weight distribution index of 7.0, and a weight average molecular weight of 120,000 g/mol is put into an extruder to extrude the molten polymer, cooled using a cooling device, and then spun using a spinning emulsifier. An oil agent was attached, and the undrawn yarn to which the oil agent was attached was wound up.

The undrawn yarn was drawn to a total draw ratio (DR) of 8.5 by two-stage drawing at about 70 to 90° C., and the drawn polyethylene fiber was subjected to an aging step using the same apparatus as in FIG. 3 . After that, the high-strength polyethylene fiber with improved cut resistance according to the present invention was prepared by winding it using an entangled device and a winder.

After the high-strength polyethylene fiber prepared above was cut to produce short 38 mm fibers, the high-strength polyethylene spun yarn with improved cut resistance of the present invention was prepared through a general spun yarn manufacturing process.

Melt index, weight average molecular weight, molecular weight distribution index and spinning temperature of polyethylene fiber, spinning speed, aging temperature and number of polyethylene spun yarns of the polyethylene resin used in each Example and Comparative Example are as the conditions in Tables 3 and 4 below. and other conditions were the same.

Comparative Example 5

A high-strength composite yarn was prepared in the same manner as in Example 1 using a 400 denier multifilament yarn, UHMWPE fiber (Dainima, Toyobo Corporation).

◈ How to measure

The strength, elongation, and cut resistance index and level of the polyethylene fibers prepared in Examples 1 to 6 and Comparative Examples 1 to 5, and cut resistance of the polyethylene spun yarn were measured.

The cut-resistance index and level, and the cut-resistance were measured after manufacturing a knitted fabric with the polyethylene spun yarns of Examples 1 to 6 and Comparative Examples 1 to 5.

The cut resistance evaluation was evaluated by covering the polyethylene spun yarn using span yarn 140D and PET 140D for screening, and knitting the manufactured covering yarn with gloves using a 13Guage L size glove knitting machine.

Examples of the cutting resistance level and cutting force are shown in Table 3, and the cutting resistance level and cutting strength of the comparative examples are shown in Table 4.

* Characteristics of polyethylene raw material: The weight average molecular weight and molecular weight distribution were measured using high-temperature GPC, and measured using Tosoh's HLC-8331 model. The measurement solvent was TCB+0.4% BHT, and the column temperature was measured at 160°C. . The sample concentration was 3 mg/mol, and Polystyrene was used as the standard sample, but the molecular weight of polyethylene was corrected by Mark-Houwink Equation to ensure smooth data.

* Melt index measurement: Measured in accordance with ASTM D1238, the measured temperature was 190℃, and the weight was defined as 2.16kg. During the measurement, preheating was performed for 5 minutes and free running for 3 minutes, and the values measured 10 times were defined as the average value. did.

* Crystallinity/Crystal Size: The degree of crystallinity and crystal size were measured using BRUKER's D8 DISCOVER.

* Strength/elongation measurement method: In accordance with ASTM D2256 standard, fiber strength and elongation were measured using Instron's Universal Testing Machine (UTM) under a measurement temperature of 20°C and a humidity of 65%.

* Cut-resistance index and level: Mesdan's glove cut tester, a device manufactured according to EN388 standard, was used for the cut-resistance evaluation method of knitted fabrics. The measurement was performed by attaching an aluminum foil wrapped with filter paper on a rubber support, placing the control sample and the test sample, measuring the control sample and the test sample before the test, measuring 5 times, and evaluated as follows to calculate the index.

<Cut resistance index>

Sequence C
control specimen T
test specimen C
control specimen I
Index One C ₁ T ₁ C _{2 i1} 2 C ₂ T ₂ C _{3 i2} 3 C ₃ T ₃ C _{4 i3} 4 C ₄ T ₄ C _{5 i4} 5 C ₅ T ₅ C _{6 i5}

[Cut resistance index (I) formula]

<Cut resistance level>

cut resistance index >1.2 >2.5 >5 >10 >20 Cut resistance level One 2 3 4 5

* Cutting resistance (N): The STM610 model manufactured by Satara, a device manufactured in accordance with ISO13997 standard, was used for the evaluation method of the cutting resistance of fabrics or knitted fabrics. Cutting is measured by the cutting resistance required to cut the material with a blade quality of 20 mm when the range of force is applied to the blade perpendicular to the sample surface. The measurement sequence is that a constant force is gradually applied between the sample and the blade, cutting within 5 seconds. and repeat the test with different forces until at least 15 records are obtained with cut lengths between 5 mm and 50 mm.

The cutting resistance is obtained in the range of 5mm to 15mm, 15mm to 30mm, and 30mm to 50mm, and the value obtained by multiplying the correction factor C by the cutting length is graphed to measure the strength when the cutting length is 20mm as the cutting resistance.

<Cutting resistance correction factor>

C = K/l

C is correction factor, l is 5.0N neoprene cutting operation length mm, K=20

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 melt index
(g/10min) 1.0 1.0 1.0 1.0 1.0 1.0 weight average
Molecular Weight (g/mol) 120,000 120,000 120,000 120,000 120,000 120,000 Molecular Weight Distribution Index 7.0 7.0 7.0 7.0 7.0 7.0 radiation temperature
(℃) 290 290 290 290 290 290 radial speed
(mpm) 160 160 160 160 160 160 aging temperature
(℃) 90 110 130 90 110 130 Crystallinity (%) 83.1 82.9 82.2 83.1 84.2 83.2 crystal size
(Å) 12.4 12.6 11.5 10.4 12.6 12.5 PE fiber strength
(g/d) 15.4 15.1 15 15.4 15.1 15 PE fiber elongation (%) 8.4 8.1 8 8.4 8.1 8 yarn count 30 30 30 15 15 15 Cut Index 8.2 8.2 8.4 7.4 7.3 7.9 Cut Level 3 3 3 3 3 3 Cutting force (N) 6.2 5.8 5.6 5.4 5.2 5.2

division Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 melt index
(g/10min) 1.0 1.0 1.0 1.0 - weight average
Molecular Weight (g/mol) 120,000 120,000 120,000 120,000 - Molecular Weight Distribution Index 7.0 7.0 7.0 7.0 - radiation temperature
(℃) 290 290 290 290 - radial speed
(mpm) 160 160 120 160 - aging temperature
(℃) 80 135 80 40 - Crystallinity (%) 71.6 73.2 67.7 68.9 - crystal size
(Å) 8.6 9.2 8.2 8.3 - PE fiber strength
(g/d) 15.5 14.2 14.9 15.2 31.2 PE fiber elongation (%) 7.6 8.8 8.1 7.6 3.1 yarn count 40 30 15 15 15 Cut Index 4.8 4.6 4.2 3.8 5.2 Cut Level 2 2 2 2 3 Cutting force (N) 4.4 4.5 3.9 3.5 4.8

As shown in Tables 3 and 4, in Examples 1 to 6 and Comparative Examples 1 to 4, polyethylene resins having a melt index of 1.0 g/10min, a molecular weight distribution index of 7.0, and a weight average molecular weight of 120,000 g/mol were used, Although spinning at a spinning temperature of 290°C, high-strength polyethylene fibers were prepared by varying the spinning speed and aging temperature.

The polyethylene fibers of Examples 1 to 6 and Comparative Examples 1 to 4 all had an elongation of 7% or more, and Examples 1 to 6 had an elongation of 8% or more, which was higher than the UHMWPE fiber of Comparative Example 5, and the fiber stiffness was When made into garments, it will have better wearability than garments made with UHMWPE fibers.

As shown in Tables 3 and 4, it can be seen that in Examples 1 to 6 and Comparative Examples 1 to 4, when the crystallinity and crystal size were increased, the cut resistance index and the cut resistance of the polyethylene spun yarn were improved. .

The polyethylene fibers of Examples 1 to 6 were manufactured at a spinning speed of 160 mpm and an aging temperature of 90 to 130° C., so that they all had a crystallinity of 75% or more, a crystal size of 10 Å or more, and a strength of 12 g/d or more. In addition, it can be seen that the polyethylene spun yarn made of the polyethylene fiber has a cut-resistance index (Cut Index) of 7 or more, a cut-resistance level (Cut Level) of 3, and a cutting resistance of 5N or more.

The polyethylene fibers of Comparative Examples 1 to 4 had a spinning speed of 160 mpm, but the aging temperature was less than 90° C. or was carried out at a temperature exceeding 130° C., the crystallinity was less than 75%, and the crystal size was less than 10 Å. Also, it can be seen that there is a large difference in crystallinity and crystal size according to the aging temperature.

In addition, it can be seen that the polyethylene spun yarns of Comparative Examples 1 to 4 have a cut resistance index (Cut Index) of less than 7, a cut resistance level (Cut Level) 2, and a cut resistance of less than 4N, which has lower physical properties than Examples 1 to 6 can

In addition, Comparative Example 5 is a polyethylene spun yarn using UHMWPE fibers. UHMWPE fibers are ultra-high molecular weight fibers obtained by stretching a polyethylene resin having an ultra-molecular weight of 1 million or more through gel spinning. It has high strength and modulus and has high elongation. It is low and has a high stiffness, so it has a stiff feeling to the touch. In addition, the elongation is low, so crimp formation is limited during the spinning yarn process, and thus the yarn shape is not smooth, so the cutting resistance is 5N or less, and the wearability is not excellent when manufacturing clothes.

Claims (11)

In the high-strength spun yarn formed of a polyethylene resin and having improved cut resistance comprising a polyethylene fiber whose main repeating unit is ethylene,
The polyethylene fiber is formed of a polyethylene resin having a melt index of 0.6 to 2 g/10 min, and a molecular weight distribution index of 5 to 10,
The polyethylene fiber has a crystallinity of 75% or more and a crystal size of 10 Å or more,
The polyethylene fiber,
A spinning step of melt-spinning a polyethylene resin having a melt index of 0.6 to 2 g/10min and a molecular weight distribution index of 5 to 10 at 230 to 290°C to form undrawn yarn;
a stretching step of stretching the undrawn yarn; and;
Including an aging step of aging the drawn polyethylene fiber at 90 ~ 130 ℃
High-strength spun yarn with improved cut resistance, characterized in that the spinning speed of the spinning step and the aging temperature of the aging step satisfy the following formula (1).
Equation (1) 210≤S+T≤290
However, S is an integer of the spinning speed (mpm) of the spinning step, and T is an integer of the aging temperature (℃) of the aging step. According to claim 1,
High-strength spun yarn with improved cut resistance, characterized in that the polyethylene fiber has a strength of 12 to 16 g/d. delete According to claim 1,
High-strength spun yarn with improved cut resistance, characterized in that the spinning speed is 120 to 160 mpm in the spinning step. According to claim 1,
The aging step is a high-strength spun yarn with improved cut resistance, characterized in that aging for 5 to 20 seconds. delete According to claim 1,
The polyethylene fiber is a high-strength spun yarn with improved cut resistance, characterized in that the fiber length is 20 to 100 mm. According to claim 1,
The high-strength spun yarn with improved cut resistance, characterized in that the number of counts is 10 to 50. An article comprising the high-strength spun yarn of any one of claims 1, 2, 4, 5, 7, 8. 10. The method of claim 9,
The article is an article, characterized in that the level (Level) according to the cut resistance standard is 3 or more. 10. The method of claim 9,
The article is an article, characterized in that the cutting force is 5.0N or more.

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