KR102809624B1 - High-strength polyethylene fiber having improved cut resistance, and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a high-strength polyethylene fiber with improved cut resistance and a method for producing the same, the method comprising: a mixing step of mixing an inorganic-containing polyethylene resin containing 10 to 50 wt% of an inorganic substance and having a melting index of 0.8 to 20 g/10 min and a general polyethylene resin having a melting index of 0.6 to 2 g/10 min; a spinning step of melt-spinning the mixed polyethylene resin at 240 to 260°C to form an undrawn yarn; and a drawing step of drawing the undrawn yarn.

Description

{HIGH-STRENGTH POLYETHYLENE FIBER HAVING IMPROVED CUT RESISTANCE, AND MANUFACTURING METHOD THEREOF}

The present invention relates to a polyethylene fiber having excellent cut resistance and a method for producing the same, and more specifically, to a high-strength polyethylene fiber having improved cut resistance of the polyethylene fiber by containing an inorganic substance and a method for producing the same.

Polyethylene resin is inexpensive and has excellent chemical resistance and product processability, so it is increasingly being used for engineering plastics, films, fibers, and non-woven fabrics. In the fiber field, it is manufactured into monofilaments and multifilaments, and its use is expanding to clothing, industrial, etc. In particular, interest in high-functionality polyethylene fibers that require high strength and high elasticity is increasing in line with the latest fiber trends.

In U.S. 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 was used, melted at a spinning temperature of 220 to 335°C, extruded through an 8-hole nozzle, and then wound at a minimum spinning speed of 30 m/min with a hot drawing temperature of 115 to 132°C and a hot tube temperature of 200 to 335°C, and then stretched 20 times or more to produce a fiber having a density of 10 to 20 g/d. However, this method has limitations in terms of production volume due to the low spinning speed according to the number of nozzle holes and the spin draw method for commercial production of polyethylene fibers, and it is difficult to produce polyethylene fibers with excellent uniformity and spinning workability when producing tens to hundreds of multifilaments.

In addition, Korean Patent Registration No. 0909559 specifies a high-strength polyethylene fiber having a weight-average molecular weight of 300,000 or less, a ratio of the weight-average molecular weight to the number-average molecular weight (Mw/Mn), which is a molecular weight distribution index, of 4.0 or less, and exhibiting high strength. 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, a high elongation of 10 times or more is required to exhibit high strength, which causes problems in that the processability, such as spinning workability, is deteriorated.

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

The present invention was invented to solve the problems of the prior art as described above, and aims to provide a polyethylene fiber with improved cut resistance by adding an inorganic substance to a polyethylene resin forming a high-strength polyethylene fiber.

In addition, the present invention aims to provide a polyethylene fiber with improved cut resistance and improved processability by mixing polyethylene resins having different melting indices.

The present invention provides a method for manufacturing a high-strength polyethylene fiber with improved cut resistance, the method comprising: a mixing step of mixing an inorganic-containing polyethylene resin containing 10 to 50 wt% of an inorganic substance and having a melting index of 0.8 to 20 g/10 min and a general polyethylene resin having a melting index of 0.6 to 2 g/10 min; a spinning step of melt-spinning the mixed polyethylene resin at 240 to 260°C to form an unstretched yarn; and a drawing step of drawing the unstretched yarn.

In addition, the present invention provides a method for manufacturing high-strength polyethylene fiber with improved cut resistance, characterized in that the inorganic material is one or two or more of titanium dioxide (TiO ₂ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), and zinc oxide (ZnO).

In addition, the present invention provides a method for manufacturing high-strength polyethylene fiber with improved cut resistance, characterized in that the inorganic polyethylene resin and general polyethylene resin are mixed in a weight ratio of 5 to 15:85 to 95.

In addition, a method for producing high-strength polyethylene fiber with improved cut resistance is provided, characterized in that the melting index of the inorganic-containing polyethylene resin is 15 to 20 g/10 min.

In addition, a high-strength polyethylene fiber with improved cut resistance is provided, characterized by being manufactured by the above-mentioned manufacturing method.

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

In addition, a high-strength polyethylene fiber with improved cut resistance is provided, characterized in that the inorganic content of the polyethylene fiber is 0.5 to 5 wt% of the total polyethylene fiber weight.

The high-strength polyethylene fiber with improved cut resistance according to the present invention has the effect of improving cut resistance by containing an inorganic substance in the polyethylene resin forming the high-strength polyethylene fiber.

In addition, the present invention has the effect of improving the processability of polyethylene fibers with improved cut resistance by mixing polyethylene resins having different melting indices.

Figure 1 is a process diagram showing a method for manufacturing high-strength polyethylene fiber with improved cut resistance according to the present invention.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the drawings attached to the present invention. First, it should be noted that among the drawings, the same components or parts are indicated by the same reference numerals as possible. In describing the present invention, a specific description of related known functions or configurations is omitted in order to avoid obscuring the gist of the present invention.

The terms “about,” “substantially,” and the like used in this specification are used in a meaning that is at or close to the numerical value when manufacturing and material tolerances inherent in the meanings mentioned are presented, and are used to prevent unscrupulous infringers from unfairly utilizing the disclosure in which exact or absolute numerical values are mentioned to aid understanding of the present invention.

Figure 1 is a process diagram showing a method for manufacturing high-strength polyethylene fiber with improved cut resistance according to the present invention.

The present invention relates to a method for manufacturing high-strength polyethylene fibers with improved cut resistance, including a mixing step, a spinning step, and a drawing step, as shown in FIG. 1.

The above-mentioned radiation step is a step of mixing an inorganic-containing polyethylene resin having a melting index of 0.8 to 20 g/10 min and containing 10 to 50 wt% of inorganic substances, and a general polyethylene resin having a melting index of 0.6 to 2 g/10 min.

The above-mentioned inorganic polyethylene resin and general polyethylene resin are preferably high-density (HDPE) polyethylene resins having a molecular weight distribution index of 5 to 10.

The above inorganic material is preferably one or two or more of titanium dioxide (TiO ₂ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), and zinc oxide (ZnO) contained in high-strength polyethylene fibers to improve cut resistance.

It is preferable that the average particle size of the above-mentioned inorganic material be 1㎛ to prevent damage to the equipment during the radiation process.

The above inorganic-containing polyethylene resin preferably has a melting index of 10 g/10 min, more preferably 15 to 20 g/10 min, for uniform dispersion of the inorganic material and fiber manufacturing processability when mixed with general polyethylene resin.

In the above mixing step, it is preferable to mix the inorganic content of the mixed polyethylene resin so that it is 0.5 to 5 wt% of the total polyethylene fiber weight. It is preferable to mix the inorganic polyethylene resin and the general polyethylene resin according to the inorganic content contained in the inorganic polyethylene resin.

In the above mixing step, it is preferable that the inorganic polyethylene resin and the general polyethylene resin are mixed in a weight ratio of 5 to 15:85 to 95. If the content of the inorganic polyethylene resin is less than 5 wt% and the inorganic content of the inorganic polyethylene resin is high, the dispersibility of the inorganic matter may be reduced, and if the content of the inorganic polyethylene resin exceeds 15 wt%, the properties of the polyethylene fiber manufactured due to the polyethylene resin having a high melting index may be reduced.

The above-mentioned spinning step is a step of forming undrawn yarn by melt spinning the mixed polyethylene resin at 240 to 260°C, and undrawn yarn can be produced in the same manner as in the production of conventional high-strength polyethylene fibers.

The above-mentioned stretching step is a step of stretching the above-mentioned unstretched yarn, and it is preferable to stretch it using a multi-roller, and it can be wound up after going through a heat fixing process after stretching.

It is preferable that the above stretching step be performed 4 to 8 times, and it would be preferable to perform stretching in three stages.

If the above stretching step is a three-stage stretching, it is preferable that the first-stage stretching temperature be 60 to 100°C, the second-stage stretching temperature be 80 to 120°C, and the third-stage stretching temperature be 100 to 120°C.

The high-strength polyethylene fiber with improved cut resistance according to the present invention manufactured as described above is preferably manufactured with a single-filament fineness of 0.5 to 2.5 denier, preferably 1 to 2 denier, and a strand count of 60 to 400.

The strength of the high-strength polyethylene fiber with improved cut resistance of the invention is preferably 10 g/d or more, preferably 12 to 16 g/d, and the elongation may be 15% or less, preferably 8 to 12%.

The high-strength polyethylene fiber with improved cut resistance of the present invention preferably has an inorganic content of 0.5 to 5 wt% of the total polyethylene fiber weight for cut resistance, more preferably 1.5 to 4.0 wt%.

The above high strength polyethylene fibers can also be used in a wide range of other types of articles.

Non-limiting examples include, for example, insulating materials for refrigerated units (e.g., refrigerators, freezers, vending machines, etc.); automotive components (e.g., front or rear seats, headrests, armrests, donor panels, rear shelves/package trays, steering wheels and interior trim, dashboards, etc.); architectural panels and components (e.g., roofs, wall cavities, underfloors, etc.); clothing (e.g., coats, shirts, pants, gloves, aprons, coveralls, shoes, boots, hats, sock liners, etc.); furniture and bedding (e.g., sleeping bags, quilts, etc.); fluid storage/transport systems (e.g., pipes or tanks for liquid/gaseous hydrocarbons, liquid nitrogen, oxygen, hydrogen, or crude oil); extreme environments (e.g., underwater or space); food and beverage products (e.g., cups, cup holders, plates, etc.); containers and bottles; etc.

Additionally, high-strength polyethylene fibers can be used in "apparel," which generally means any article that is configured to fit a portion of the body. Examples of such articles include, without limitation, clothing (e.g., shirts, pants, jeans, slacks, skirts, coats, activewear, athletic wear, aerobics, and gym wear, swimwear, cycling jerseys or shorts, swimwear/bathing suits, race suits, sweat suits, bodysuits, and the like); footwear (e.g., shoes, socks, boots, and the like); protective clothing (e.g., firefighter coats), clothing accessories (e.g., belts, bra straps, side panels, gloves, socks, leggings, orthopedic braces, and the like), undergarments (e.g., underwear, t-shirts, and the like), compression garments, wrap garments (e.g., kilt loincloths, togas, ponchos, capes, shawls, and the like).

Hereinafter, high-strength polyethylene fibers with improved cut resistance were manufactured according to examples according to the present invention. The present invention is not limited to these examples.

Example 1 to 6, Comparative example

A general polyethylene resin having a melting index of 1 g/10 min and an inorganic-containing polyethylene resin containing 20 wt% or 40 wt% of inorganic matter were fed into an extruder to extrude a molten polymer, which was then cooled using a cooling device, and then a spinning agent was attached using a spinning agent applying device, and an undrawn yarn to which the agent was attached was wound up, and the undrawn yarn was drawn and heat-treated. The general polyethylene resin and the inorganic-containing polyethylene resin were mixed in a weight ratio of 10:90.

Thereafter, a high-strength polyethylene fiber with improved processability according to the present invention was manufactured by winding using a winding device and a winder.

The above stretching was performed in three stages using a multi-stage stretching roller, with the first-stage stretching temperature being approximately 70±3℃, the second-stage stretching temperature being approximately 92±3℃, and the third-stage stretching temperature being approximately 105±3℃.

The melting index, inorganic type, and inorganic content of the inorganic-containing polyethylene resin according to the examples and comparative examples are shown in Table 1.

◈ Measurement method

The strength, elongation, operability, cutting resistance, and cutting resistance level of the high-strength polyethylene fibers manufactured in Examples 1 to 6 and Comparative Examples were measured.

The above-mentioned cutting strength and cut resistance levels were evaluated by manufacturing a knitted fabric by covering the covering yarn with polyethylene fibers of Examples 1 to 6 and Comparative Examples using Spandex 140D and PET 140D for examination, and knitting the manufactured covering yarn using a 13 Guage L size glove knitting machine.

* Melt Index: Measured according to ASTM D1238dp. The measurement temperature was 190℃ and the melt index was defined as 2.16kg based on the weight. During the measurement, preheating was performed for 5 minutes and prerunning was performed for 3 minutes. The average value was defined as the value measured 10 times.

* Measuring strength of yarn: The strength was measured using a universal testing machine UTM (Universal Testing Mechine, INSTRON) in accordance with ASTM D-2256. The strength was defined as the average value of 10 measurements taken at a speed of 300 mm/min at a measurement temperature of 20℃ and a relative humidity of 65%.

* Cutting strength (N) and cutting resistance Level

The method for evaluating the cutting resistance of woven or knitted fabrics used the STM610 model from Satara, a device manufactured according to the ISO13997 standard. The cutting is measured as the cutting resistance required to cut the material with a blade stroke of 20 mm when the force range is applied to the blade perpendicular to the sample surface. The measurement sequence is to gradually apply a constant force between the sample and the blade, start cutting within 5 seconds, and repeat the test with different forces until at least 15 records are obtained with a cutting length between 5 mm and 50 mm. The cut resistance level was measured through the measured cutting resistance, as shown in Table 1.

Cut resistance Level A B C D E F Cutting force (N) 2 5 10 15 22 30

* Operational efficiency evaluation method: Evaluated by the number of times per 24 hours when winding unstretched yarn during spinning (the basis for judging the productivity of the product)

△: 21~30 times/day

○: 11~20 times/day

◎ : 0~10 times/day

division Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative example General PE
Melting index
(g/10min) 1 1 1 1 1 1 1 PE containing minerals
Melting index
(g/10min) 1 1 1 15 20 25 - Inorganic substances SiO ₂ TiO ₂ TiO ₂ TiO ₂ TiO ₂ TiO ₂ - In the fabric
Mineral content
(weight%) 2 4 2 2 2 2 - Denier /
Filament 400 / 240 400 / 240 400 / 240 400 / 240 400 / 240 400 / 240 400 / 240 Strength (g/d) 14.8 14.7 14.9 14.2 14 13.5 15.1 Believers (%) 8.27 8.56 8.75 8.75 8.99 9.43 8.92 Cutting force (N) 15.91 16.24 15.57 15.27 15.33 15.11 12.93 Cut resistance Level D D D D D D C Operability △ △ ○ ◎ ◎ ○ ◎

As shown in Table 2, the polyethylene fibers of Examples 1 to 4 and the Comparative Examples do not differ significantly in strength and elongation, but in terms of cutting resistance and cut resistance level, the polyethylene fibers of Examples 1 to 4 containing inorganic substances have superior cut resistance than the Comparative Examples, indicating that cutting resistance is greatly improved when inorganic substances are included.

In the cases of Examples 1 to 4, it can be seen that as the melting index of the inorganic polyethylene resin increases, the flowability improves and the operability is enhanced. However, in Example 6, where the melting index exceeds 20 g/10 min, the strength decreases, so it is preferable that the melting index of the inorganic polyethylene resin be 15 to 20 g/10 min.

Claims (7)

In a method for manufacturing high-strength polyethylene fiber,
A mixing step of mixing an inorganic-containing polyethylene resin having a melting index of 0.8 to 20 g/10 min and containing 10 to 50 wt% of inorganic substances and a general polyethylene resin having a melting index of 0.6 to 2 g/10 min;
A spinning step of forming unstretched yarn by melt spinning a mixed polyethylene resin at 240 to 260°C;
Including an extension step for extending the above-mentioned unextended material,
A method for manufacturing high-strength polyethylene fiber with improved cut resistance, characterized in that the above-mentioned inorganic-containing polyethylene resin and general polyethylene resin are mixed in a weight ratio of 5 to 15:85 to 95. In the first paragraph,
A method for manufacturing high-strength polyethylene fiber with improved cut resistance, characterized in that the inorganic material is one or two or more of titanium dioxide (TiO ₂ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), and zinc oxide (ZnO). delete In the first paragraph,
A method for producing high-strength polyethylene fiber with improved cut resistance, characterized in that the melting index of the above-mentioned inorganic-containing polyethylene resin is 15 to 20 g/10 min. A high-strength polyethylene fiber with improved cut resistance, characterized in that it is manufactured by a manufacturing method according to any one of claims 1, 2, and 4. In paragraph 5,
A high-strength polyethylene fiber with improved cut resistance, characterized in that the strength of the polyethylene fiber is 12 to 16 g/d. In paragraph 5,
A high-strength polyethylene fiber with improved cut resistance, characterized in that the inorganic content of the polyethylene fiber is 0.5 to 5 wt% of the total polyethylene fiber weight.

Images