KR102669675B1 - Polyethylene composite fiber with excellent cooling feel and elasticity - Google Patents

Abstract

The present invention relates to a high-strength polyethylene composite fiber with excellent cold sensitivity and elasticity, which is formed in a side-by-side form from a high melt index polyethylene resin and a low melt index polyethylene resin, and exhibits both cold sensitivity and elasticity.

Description

High-strength polyethylene composite fiber with excellent coolness and elasticity {POLYETHYLENE COMPOSITE FIBER WITH EXCELLENT COOLING FEEL AND ELASTICITY}

The present invention relates to a high-strength polyethylene composite fiber with excellent cold sensitivity and elasticity, which is expressed as a side-by-side type polyethylene composite fiber using polyethylene resins with different melt indices.

Currently, only polyester and nylon fibers are the side-by-side type of elastic yarns that have been developed and commercialized in the textile industry.

The above fibers are suitable for general daily clothing that requires elasticity and functionality, but they are insufficient in strength and chemical resistance to be applied to safety protection clothing, parts, and miscellaneous goods, which are the recent trends, leading to a growing demand for new fiber materials. It is increasing.

Polyethylene resin is inexpensive, has excellent chemical resistance, and product processability, so its use is increasing for engineering plastics, films, fibers, and non-woven fabrics. In the textile field, it is manufactured as monofilament and multifilament and is used for clothing, industrial purposes, etc. Its uses are expanding. In particular, according to the latest fiber trends, interest in high-performance polyethylene fibers that require high strength and high elastic modulus is increasing.

In U.S. Patent No. 4,228,118, polyethylene resin with a number average molecular weight of 20,000 or more and a weight average molecular weight of 125,000 or less is used and melted at a spinning temperature of 220 to 335°C, then extruded through an 8-hole nozzle and hot stretched at a hot stretching temperature of 115 to 132°C. The tube was wound at a minimum spinning speed of 30 m/min at a temperature of 200 to 335°C and then stretched more than 20 times to produce a fiber of 10 to 20 g/d. However, in the commercial production of polyethylene fibers, this method has limitations in production due to the low spinning speed depending on the number of nozzles and the spin draw method, and produces polyethylene fibers with excellent uniformity and spinning workability when producing tens to hundreds of multifilaments. There is difficulty in doing so.

In addition, Republic of Korea Patent No. 0909559 specifies high-strength polyethylene fibers that have a weight average molecular weight of 300,000 or less, a ratio of weight average molecular weight to number average molecular weight (Mw/Mn), which is a molecular weight distribution index, of 4.0 or less, and exhibit high strength. I'm doing it. However, it is difficult to control the molecular weight distribution index of the raw material below 4.0, and since the molecular weight distribution index is formed to be low, high stretching of more than 10 times is required to develop high strength, resulting in a decrease in fairness such as spinning workability.

In addition, in Republic of Korea Patent No. 2183247, it was formed of a polyethylene resin alone with a melt index of 0.6 to 4 g/10 min and a molecular weight distribution index of 5 to 10, so that not only high strength but also cooling functionality was achieved through the development of appropriate thermal conductivity.

However, problems still remained in overcoming high-strength stiffness due to the limitations of single spinning.

The present invention was invented to solve the problems of the prior art as described above. It is formed in a side-by-side type using polyethylene resins with different melt indexes, so that it has high strength and exhibits elasticity due to the crimp generation effect due to the difference in melt index. The purpose is to provide high-strength polyethylene composite fibers with excellent cooling sensation and elasticity that are possible and also have cooling performance due to the high thermal conductivity characteristics of polyethylene.

In addition, the purpose of the present invention is to provide a high-strength polyethylene composite fiber with excellent coolness and elasticity, which is a material optimized for summer work clothes and protective equipment.

The present invention provides a high-strength polyethylene composite fiber with excellent coolness and elasticity, which is formed in a side-by-side form with a high melt index polyethylene resin and a low melt index polyethylene resin.

In addition, the high-melt index polyethylene resin provides a high-strength polyethylene composite fiber with excellent coolness and elasticity, characterized in that the polyethylene resin has a melt index of 2 to 20 g / 10 min and a molecular weight distribution index of 2 to 10.

In addition, the low melt index polyethylene resin provides a high-strength polyethylene composite fiber with excellent coolness and elasticity, characterized in that it is a polyethylene resin with a melt index of 0.6 to 4 g/10 min and a molecular distribution index of 5 to 10.

In addition, the high melt index polyethylene resin and the low melt index polyethylene resin provide high-strength polyethylene composite fibers with excellent coolness and elasticity, characterized in that the K value of the following formula (1) is in the range of 0.35 ≤ K ≤ 0.95. .

Equation (1) K=( MI ] _l -[ MI ] _h )/([ MI ] _h +[ MI ] _l )

However, [ MI ] _h high viscosity melt index, [ MI ] _l low viscosity melt index

In addition, a high-strength polyethylene composite fiber with excellent coolness and elasticity is provided, wherein the high melt index polyethylene resin and the low melt index polyethylene resin have a weight ratio of 20:80 to 80:20.

In addition, the present invention is an article characterized by comprising the above high-strength polyethylene composite fiber.

In addition, the above-mentioned article provides an article characterized in that it has a level of 3 or higher according to the cut resistance standard.

In addition, the article provides an article characterized by an elasticity of 20% or more.

In addition, the article provides an article characterized in that the Qmax value is 0.2 or more.

As described above, the high-strength polyethylene composite fiber with excellent coolness and elasticity according to the present invention is formed in a side-by-side type using polyethylene resins with different melt indices, so that it has high strength and also exhibits elasticity due to the crimp generation effect due to the difference in melt index. This is possible and has the effect of having cooling performance due to the high thermal conductivity characteristics of polyethylene.

In addition, the present invention has the effect of providing a material optimized for summer work clothes and protective equipment with high elasticity and cold sensitivity.

Hereinafter, a preferred embodiment of the present invention will be described in detail. First, in describing the present invention, detailed descriptions of related well-known functions or configurations are omitted in order to not obscure the gist of the present invention.

As used herein, the terms 'about', 'substantially', etc. are used to mean at or close to the numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and are used to enhance the understanding of the present invention. Precise or absolute figures are used to assist in preventing unscrupulous infringers from taking unfair advantage of stated disclosures.

The present invention relates to a high-strength polyethylene composite fiber with excellent coolness and elasticity formed in a side-by-side form from a high melt index polyethylene resin and a low melt index polyethylene resin.

The polyethylene resin of the high melt index is a polyethylene fiber whose main repeating unit is ethylene, and has a melt index of 2 to 20 g/10 min and a molecular weight distribution index of 2 to 10.

It is more preferable that the melt index of the high melt index polyethylene resin is 4 to 10 g/10 min.

The low melt index polyethylene resin is a polyethylene fiber whose main repeating unit is ethylene, a melt index of 0.6 to 4 g/10 min, and a molecular weight distribution index of 5 to 10.

It is more preferable that the melt index of the low melt index polyethylene resin is 1 to 4 g/10 min.

It is preferable that the high melt index polyethylene resin and the low melt index polyethylene resin have a K value in the range of 0.35≤K≤0.95 in the following formula (1).

Equation (1) K=( MI ] _l -[ MI ] _h )/([ MI ] _h +[ MI ] _l )

However, [ MI ] _h high viscosity melt index, [ MI ] _l low viscosity melt index

If the K value is more than 0.95, excessive flow difference causes non-spinning and bending phenomenon, making it impossible to secure yarn fairness, and if the K value is less than 0.35, satisfactory elasticity function is not achieved due to the small flow difference. It is difficult to manifest.

The high-strength polyethylene composite fiber with excellent coolness and elasticity of the present invention is preferably formed of the high melt index polyethylene resin and the low melt index polyethylene resin in a weight ratio of 20:80 to 80:20.

As described above, the high-strength polyethylene composite fiber of the present invention, which is formed of a high-melt index polyethylene resin and a low-melt index polyethylene resin, and has excellent coolness and elasticity, can be manufactured like conventional high-strength polyethylene fibers and composite fibers, and can be manufactured at a low spinning temperature. It is spun in the range of 220~290℃ and can be manufactured at a spinning speed of 300~2000mpm.

The spun polyethylene composite fiber can be stretched using a multi-stage stretching roller, and it is preferable to stretch it in two or three stages at 60 to 120°C. At this time, a draw ratio of 5 to 10 would be desirable.

In order to further enhance the cooling performance after the stretching, aging can be performed in a dry heat chamber. When aging is performed, it is preferable to perform aging at a temperature of 90 to 130 ° C. for 5 to 20 seconds.

The high-strength polyethylene composite fiber with excellent coolness and elasticity according to the present invention manufactured as described above has an excellent strength of 10 to 20 g/d, and contains the high-strength polyethylene composite fiber of the present invention and has excellent resistance when manufactured into fabric or knitwear. It will be possible to manufacture products with Cut Level 3 or higher.

In addition, the article containing the high-strength polyethylene composite fiber with excellent cold sensitivity and elasticity of the present invention preferably has a Qmax value, which is a cold sensitivity index, of 0.20 or more and elasticity of 20% or more.

The high-strength polyethylene composite fiber with excellent coolness and elasticity of the present invention may be used in a wide range of other types of articles.

Non-limiting examples include, for example, insulating materials for refrigeration units (e.g., refrigerators, freezers, vending machines, etc.); Automotive parts (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, underfloor heating, etc.); Clothing (e.g., coats, shirts, pants, gloves, aprons, coveralls, shoes, boots, hats, sock liners, etc.); Furniture and bedding (e.g. sleeping bags, blankets, etc.); Fluid storage/transfer 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; Includes etc.

High-strength polyethylene composite fibers may also be used in “garment,” which is generally meant to include any article shaped to fit against a part of the body. Examples of such articles include, but are not limited to, clothing (e.g., shirts, pants, jeans, slacks, skirts, coats, activewear, sportswear, aerobic, and gym clothes, swimwear, cycling jerseys or shorts, and bathing suits/bathing suits). suit), lace suit, sweat suit, bodysuit, etc.); Footwear (e.g., 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 wearing clothing (e.g. kilts, loincloths, togas, ponchos, capes, shawls, etc.)

Hereinafter, examples of a method for producing high-strength polyethylene composite fibers with excellent coolness and elasticity according to the present invention are shown, but the present invention is not limited to the examples.

Examples 1 to 6 and Comparative Examples 1 to 4

Using a general side-by-side composite spinning facility, the process was carried out as follows.

The high melt index polyethylene resin used was a polyethylene resin with a molecular weight distribution index of about 5.0 and a weight average molecular weight of about 120,000 g/mol, while the low melt index polyethylene resin used a polyethylene resin with a molecular weight distribution index of about 7.0 and a weight average molecular weight of about 100,000 g/mol. The molten polymer was extruded and cooled using a cooling device. Then, a spinning emulsion was applied using a spinning emulsion application device, and the undrawn yarn to which the emulsion was attached was wound.

The undrawn yarn was stretched to a total draw ratio (DR) of 8.5 by multistage stretching at about 70 to 90°C, and the stretched polyethylene composite fiber was subjected to an aging step at 95 to 130°C for 10 seconds using a dry heat chamber. Afterwards, the high-strength polyethylene composite fiber with improved coolness and elasticity according to the present invention was manufactured by winding it using a entanglement device and a winder.

The melt index, weight ratio, and K value of the high melt index polyethylene resin and the low melt index polyethylene resin used in each Example and Comparative Example are shown in Table 1, and other spinning conditions were performed in the same manner.

division High viscosity resin
low viscosity resin
K value profit MI
(190℃/10min) weight ratio
(%) profit MI
(190℃/10min) weight ratio
(%) Example 1 P.E. 4 50 P.E. One 50 0.6 Example 2 P.E. 4 20 P.E. One 80 0.6 Example 3 P.E. 4 80 P.E. One 20 0.6 Example 4 P.E. 10 50 P.E. One 50 0.82 Example 5 P.E. 10 50 P.E. One 10 0.82 Example 6 P.E. 20 50 P.E. 4 50 0.67 Comparative Example 1 P.E. 4 10 P.E. One 90 0.6 Comparative example 2 P.E. 20 50 P.E. 10 50 0.33 Comparative Example 3 P.E. One 50 P.E. 0.6 50 0.25 Comparative example 4 PTT 1.2(IV) 50 PET 0.5(IV) 50 -

◎ Physical property evaluation method

The spinning processability, strength, crimp rate, elasticity, cut resistance index and level, and Qmax value, a cold sensation index, of Examples 1 to 6 and Comparative Examples 1 to 4 were measured and are shown in Table 2.

The elasticity, cut resistance index and level, and Qmax values were measured after producing knitted fabrics with the polyethylene fibers of Examples 1 to 6 and Comparative Examples 1 to 4.

The cut resistance was evaluated by covering polyethylene fibers using spandex 140D and PET 140D, and knitting the manufactured covering yarns into gloves using a 13Guage L size glove knitting machine to produce knitted fabrics.

division Radiation fairness
(%) Crimp rate
(%) robbery
(g/d) Flexibility
(%) Qmax Cut
Index Cut Level Example 1 95 50 13 38 0.28 8.2 3 Example 2 91 46 15 32 0.27 8.6 3 Example 3 92 42 11 30 0.24 7.6 3 Example 4 94 55 12 42 0.28 7.8 3 Example 5 95 38 17 28 0.21 9.1 3 Example 6 92 47 9 33 0.24 7.1 3 Comparative Example 1 30 25 15 14 0.19 8.5 3 Comparative example 2 94 46 4.8 30 0.24 3.2 One Comparative example 3 75 12 18 3 0.15 9.1 3 Comparative example 4 95 46 4.2 32 0.09 2.8 One

As shown in Table 2, it can be seen that Examples 1 to 6 have excellent spinning processability, strength, elasticity, cold sensitivity performance and cut resistance, with K values ranging from 0.35 to 0.95. In particular, with high melt index polyethylene resin, 10g/ It would be preferable to use a polyethylene resin of 10 g/10 min or less because Examples 1 to 5, which were less than 10 min, had better strength than Example 6, which was more than 10 g/10 min.

In Comparative Example 1, it can be seen that the weight ratio of low viscosity is too high, so the fairness is greatly reduced, and in addition, the elasticity and crimp rate are drastically reduced.

In the case of Comparative Example 2, the K value was lower than 0.35, and the flow properties of both high and low viscosity were high, so it was not possible to obtain a strength that satisfied the cutting resistance.

In addition, in the case of Comparative Example 3, the difference between the high-viscosity resin and the low-viscosity resin was too small, and the K value was lower than 0.35, making it difficult to develop elasticity.

In the case of crimped yarn using conventional polytrimethylene terephthalate (PTT) resin and polyethylene terephthalate (PET) resin rather than the polyethylene resin of Comparative Example 4, elasticity was excellent, but cut resistance strength and cold performance were very poor. Able to know.

◈ Measurement method

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

* Strength measurement method: Fiber strength was measured using Instron's Universal Testing Machine (UTM) at a measurement temperature of 20°C and humidity of 65% in accordance with ASTM D2256 standards.

* Fairness evaluation: 1st grade production / total production * 100 = yield (by weight)

* Crimp rate (Tc, %): Measures the crimp rate of the fiber. A sample is taken from a 1m-long skein equal to 3,000 ÷ fineness ÷ 4. When crimping occurs during hot water treatment of this sample, a load of 1 g, which is a level at which tangles of each fiber strand does not occur, was applied and treated in hot water (100°C) for 20 minutes. The load was removed and left for 4 hours. Let it dry naturally. After natural drying, a load of 6g is applied to the sample, and after 1 minute, the length L1 is measured. A load of 600g is applied, and the length L2 is measured after 1 minute. The crimp rate is calculated from the value measured in this way using the following formula.

Crimp rate (%) = (L2 - L1)/L2 × 100

* Elasticity: Measure the elasticity of the fabric by taking a 1m long piece in the horizontal and vertical directions, immersing it in distilled water at 60℃, boiling for 15 minutes, then boiling for 15 minutes, immersing it in 2g/l erkantol BX aqueous solution at 60℃ for 30 seconds, taking it out again and soaking it in wet water. Measure X1 after 1 minute of load of 0.2g/D, dry for 1 hour at 50~60℃, cool for 1 hour, measure X2 after 1 minute of load of 0.002g/D, and calculate elasticity using the formula below.

Elasticity (%)=((X1-X2)/ X1)100

* Contact cooling sensitivity (Qmax): An instantaneous sample that occurs initially after contacting a heat source plate with a finite amount of heat higher than the surface temperature of the sample to the sample using the KES-F7 system (thermo Labo Type: Kato tech Co.,LTD) The Qmax value, which is the maximum heat absorption of the furnace, was measured and used as a scale related to the feeling of cold. In this measurement, water at room temperature (20°C) was circulated in a water bath to maintain the temperature of the sample surface at the same room temperature. Considering the difference in skin temperature, the temperature difference between the heat source plate and the sample was set to 10°C. The contact pressure of the heat source plate with respect to the sample was measured at a constant level of 12.5gf/cm2.

* Cut resistance index and level: The cut resistance evaluation method of knitted fabric used Mesdan's Glove cut tester, a device manufactured in accordance with EN388 standards. For the measurement, an aluminum foil wrapped with filter paper was attached to the rubber support, the control and test samples were placed, and the control and test samples were measured before the test, measured 5 times, evaluated as follows, and the index was calculated.

<Cutting 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}

[Cutting resistance index (I) formula]

<Cutting resistance level>

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

Claims (9)

It is formed in a side-by-side form with high melt index polyethylene resin and low melt index polyethylene resin,
The high-melt index polyethylene resin and the low-melt index polyethylene resin are high-strength polyethylene composite fibers with excellent coolness and elasticity, characterized in that the K value of the following formula (1) is in the range of 0.35≤K≤0.95.
Equation (1) K=( MI ] _l -[ MI ] _h )/([ MI ] _h +[ MI ] _l )
However, [ MI ] _h high viscosity melt index, [ MI ] _l low viscosity melt index According to paragraph 1,
The polyethylene resin of the high melt index is a high-strength polyethylene composite fiber with excellent coolness and elasticity, characterized in that the polyethylene resin has a melt index of 2 to 20 g / 10 min and a molecular weight distribution index of 2 to 10. According to paragraph 1,
The low melt index polyethylene resin is a high-strength polyethylene composite fiber with excellent coolness and elasticity, characterized in that it is a polyethylene resin with a melt index of 0.6 to 4 g / 10 min and a molecular distribution index of 5 to 10. delete According to paragraph 1,
A high-strength polyethylene composite fiber with excellent coolness and elasticity, characterized in that the high melt index polyethylene resin and the low melt index polyethylene resin have a weight ratio of 20:80 to 80:20. An article comprising the high-strength polyethylene composite fiber of any one of claims 1, 2, 3, and 5. According to clause 6,
The product is characterized in that it has a level of 3 or higher according to the cut resistance standard. According to clause 6,
The article is characterized in that the article has an elasticity of 20% or more. According to clause 6,
The article is characterized in that the Qmax value is 0.2 or more.