High-strength polyethylene original yarn with improved shrinkage ratio and manufacturing method thereof

Abstract

To provide high-strength polyethylene original yarn with an improved shrinkage ratio and a manufacturing method thereof.SOLUTION: A ratio (A / B) is 16 or over, wherein A is the highest point of an intensity peak formed in a scattering vector of 0-0.04Å-1 in small angle X-ray scattering (SAXS) and B is the highest point of an intensity peak formed in a scattering vector of 0.05-0.08Å-1, a shrinkage ratio is 2.5% or over, a crystallinity is 65-85%, a weight-average molecular weight (Mw) is over 300,000 g / mol and 600,000 g / mol or under, and a molecular weight distribution is over 5 and under 9.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a high-strength polyethylene raw yarn having an improved shrinkage rate and a method for producing the same. Specifically, it is possible to manufacture a roll of paper with a specific microstructure, improved shrinkage rate, and high density. The present invention relates to a high-strength polyethylene raw yarn and a method for producing the same. [Background technology]

[0002] Not only those involved in the security field, such as police and military personnel, In addition, people who handle sharp cutting tools in a variety of other industrial sectors are also at constant risk of injury. To minimize the risk of injury, protective products such as gloves or clothing should be provided. It must be done.

[0003] The protective product provides adequate protection for the human body against weapons such as knives or sharp cutting tools. In order to achieve this, it is required to have cut resistance.

[0004] To provide the protective product with high cut resistance, high strength polyethylene yarn is used in the protective product. For example, high-strength polyethylene yarn is used alone to manufacture rolls of fabric. or after high-strength polyethylene yarn and other types of yarn are combined to form a ply-twisted yarn, The ply-twisted yarn can be used to manufacture a raw material roll.

[0005] Ultra-high molecular weight polyethylene (UHMWPE) is a type of high-strength polyethylene yarn. In order to solve the environmental problems caused by the use of organic solvents in the gel spinning method, A melt-spun yarn made of high-density polyethylene with a low weight-average molecular weight has also been developed. do.

[0006] High density polyethylene polymers, unlike other polymers, have a very small number of short or long The molecular chain has branches. Due to the effect of such branching, Most of the high-strength polyethylene yarns produced by the melt spinning method have high crystallinity and low shrinkage. If the shrinkage rate is low, the yarn can be used in the weaving and knitting processes to manufacture finished products. The disadvantage is that the density of the weaving and knitting of the product can only be determined by the It is difficult to manufacture a high density raw material with a higher density than the density determined by the density of the knitting and weaving. It is possible. Summary of the Invention [Problem to be solved by the invention]

[0007] One object of the present invention to solve the problems of the prior art is to provide a high strength polyethylene having an improved shrinkage ratio. The present invention provides a raw rayon yarn and a method for producing the same.

[0008] It also enables the production of fabric that is highly cut-resistant and provides an excellent wearing comfort. The present invention provides a polyethylene raw yarn and a method for producing the same.

[0009] In addition, it has a higher areal density than the areal density that can be adjusted in existing weaving and knitting processes. The present invention aims to provide a high-strength polyethylene raw yarn and a method for producing the same, which can provide a raw roll having the above properties. do. [Means for solving the problem]

[0010] As a result of research conducted in order to achieve the above object, the inventors of the present invention have discovered a method for manufacturing a semiconductor device having a specific microstructure. By producing polyethylene yarn with high shrinkage, the shrinkage rate of the yarn is improved and high strength materials are produced. The present invention has been completed based on the discovery that the above-mentioned properties can be expressed.

[0011] In addition, by using such polyethylene yarn having an improved shrinkage rate for weaving and knitting, This allows us to provide a higher density base fabric that has high cut resistance and excellent wearability. The present invention has been completed based on the discovery that it is possible to manufacture a base sheet capable of providing such a feeling.

[0012] The polyethylene raw yarn having the specific microstructure is analyzed by small angle X-ray scattering (S The scattering vector of the AXS (axial scattering x-ray diffraction) is in a specific range. It has been found that it is possible to achieve the desired physical properties with a raw yarn that satisfies the required structure.

[0013] In the present invention, the scattering vector of small angle X-ray scattering (SAXS) described below is As long as it is possible to produce a raw yarn that satisfies a specific range, the means is not limited. For example, The molecular weight distribution of the ethylene resin, the spinning temperature during the production of the raw yarn, the draw ratio, and the draw temperature are determined according to a specific The scattering vector of the small angle X-ray scattering (SAXS) can be adjusted to the range. As long as the range satisfies the range described below, there is no limitation thereto.

[0014] In one embodiment of the present invention, the scattering vector of small angle X-ray scattering (SAXS) is 0 to 0.04 Å. -1 To The highest point A of the intensity peak that occurs and the scattering vector 0.05 to 0. 08Å -1 Ratio of the intensity peak at point A to the highest point B (A / B) The present invention relates to a polyethylene raw yarn having a molecular weight of 16 or more and a shrinkage rate of 2.5% or more.

[0015] In one embodiment, the raw yarn has a melt index (MI) measured at 190° C. and 2.16 kg. The molecular weight distribution may be more than 5 and less than 9.

[0016] In one embodiment, the raw yarn may have a crystallinity of 65 to 85%. In one embodiment, the raw yarn may have a melting temperature of 130 to 140°C. In one embodiment, the raw yarn has a density of 0.93 to 0.97 g / cm 3 It is possible.

[0017] Another aspect of the present invention is a method for producing a polyethylene raw yarn, comprising the steps of: The melt index (MI) measured at 190℃ and 2.16 kg is 0.3 to 6 g / 10 min. The polyethylene chips having a molecular weight distribution of more than 5 and less than 9 are melted to produce a polyethylene melt. Obtaining a melt; Spinning the polyethylene melt through a die having a plurality of nozzle holes. and, A plurality of fibrils are formed when the polyethylene melt is discharged from the nozzle hole. allowing the lament to cool; and The cooled filaments are then bundled together to form a multifilament yarn. Tep and drawing the multifilament yarn at a total draw ratio of 5 to 20 times and heat fixing the yarn; , winding the drawn and heat-set multifilament yarn; The small angle X-ray scattering (SAXS) vector is 0 to 0.04 Å. -1 Occurs in The highest point A of the intensity peak and the scattering vector 0.05 to 0.08 Å -1 The ratio (A / B) of the intensity peak generated at the highest point B is 16 or more. and a method for producing polyethylene raw yarn having a shrinkage rate of 2.5% or more.

[0018] In one embodiment, the spinning temperature of the polyethylene melt may be 220 to 300°C. In one embodiment, the maximum stretching temperature during the stretching may be 100 to 150°C.

[0019] In one embodiment, the drawing step may be performed by multi-stage drawing. In one embodiment, the stretching step is performed using a plurality of godet rollers. Ugh. In one embodiment, the drawing step is performed in a multi-stage drawing step of 4 stages or more and 20 stages or less. Possible.

[0020] In one embodiment, the plurality of godet rollers are set at a temperature of 50 to 150° C., The temperature of the first godet roller among the plurality of godet rollers is 50 to 80° C. The temperature of the last godet roller among the plurality of godet rollers is 100 to 150° C. the law of nature, Among the plurality of godet rollers, the godet rollers other than the first and last godet rollers The temperature of each godet roller is the same as that of the godet roller immediately preceding it. or even higher. Effect of the Invention

[0021] The polyethylene yarn of the present invention has a specific microstructure, which gives it high strength. It is also possible to provide a polyethylene raw yarn having an improved shrinkage rate.

[0022] In addition, raw rolls of woven or knitted fabrics manufactured from such polyethylene raw yarns have been It provides a higher density base cloth compared to base cloth made with high-strength polyethylene base yarn. It is possible.

[0023] In addition, although the polyethylene fiber according to the present invention is produced by melt spinning, The high strength of the material makes it suitable for use in protective products with excellent cut resistance. be. [Brief description of the drawings]

[0024] [Figure 1] 1 is a small angle X-ray scattering (SAXS) graph of the raw yarn according to Example 1. [Diagram 2] 1 is a small angle X-ray scattering (SAXS) graph of the raw yarn according to Example 2. [Diagram 3] 1 is a small angle X-ray scattering (SAXS) graph of the raw yarn according to Example 3. [Figure 4] 1 is a small angle X-ray scattering (SAXS) graph of the raw yarn according to Comparative Example 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] The present invention will now be described in more detail. Unless otherwise defined, all technical and scientific terms are understood to be within the meaning of the art to which this invention belongs. The terms used in the description of the present invention have the same meaning as commonly understood by one person. The terms are merely used for the purpose of describing particular embodiments and are not intended to limit the invention. It is not something to do.

[0026] Furthermore, the singular forms used in the specification and the appended claims shall not be construed as limiting the scope of the invention unless the context clearly indicates otherwise. Unless otherwise indicated, the plural forms are intended to be included.

[0027] In addition, when a part "contains" a certain component, this means that, unless otherwise specified to the contrary, It means that other components may be included, rather than excluding other components. .

[0028] The inventors of the present invention have developed a high-strength polyethylene that is both high in strength and can achieve a high shrinkage rate. As a result, we developed a polyethylene base material with a specific fine crystal structure. We have found that such properties can be achieved with yarn.

[0029] Specifically, one embodiment of the present invention is a method for producing a small-angle X-ray scattering (SAXS) scattering vector of 0 to 0.04 Å -1 The highest point A of the peak intensity (Intensity Peak) and the scattering vector 0.0 5~0.08Å -1 The ratio of the intensity peak generated at the highest point B (A / B) is 16 or more and the shrinkage rate is 2.5% or more. Within the range where the A / B and shrinkage ratio of the small angle X-ray scattering (SAXS) are satisfied simultaneously, It is possible to manufacture high-density rolls of fabric that are strong and have a high shrinkage rate. We have discovered and completed the present invention.

[0030] The A / B ratio of the small angle X-ray scattering (SAXS) is 16 or more, preferably 18 or more, and more preferably It may be 20 or more and 40 or less. Specifically, it may be 16 to 35. A specific fine crystal structure is formed at, and as a result, the shrinkage rate is 2.5% or more, more preferably A material that satisfies a shrinkage rate of 3% or more, 3.5% or more, 4% or more, specifically 2.5 to 10%. The shrinkage rate means a dry heat shrinkage rate at 100°C. In addition, a high strength raw yarn can be provided.

[0031] The present invention relates to a material having a small angle X-ray scattering (SAXS) A / B ratio of 16 or more and a shrinkage ratio of 2.5 % or more at the same time, there is no restriction on the manufacturing method. Examples include the molecular weight distribution of polyethylene resin, the spinning temperature during the production of raw yarn, and the elongation. It can be produced by adjusting the stretch ratio and stretching temperature within a specific range.

[0032] More specifically, the polyethylene resin with a molecular weight distribution of more than 5 and less than 9 is used. The spinning temperature is 220 to 300°C, and the stretch ratio is 5 to 20 times. The stretching temperature may be 100 to 150° C. However, the above conditions are merely examples. This is not intended to be a limitation. Various conditions in the ordinary technical field may be modified to implement the invention. and are intended only to illustrate or explain the present invention and are not intended to limit the scope of the present invention. It's not something like that.

[0033] The configuration of the present invention will be described more specifically below.

[0034] In one embodiment of the present invention, the polyethylene resin used as the raw material is a repeating unit. The term refers to a copolymer in which the copolymer is essentially composed of ethylene and small amounts of other monomers, such as α-olefins. acrylic acid and its derivatives, methacrylic acid and its derivatives, vinyl silanes and It may also be a copolymer of ethylene and its derivatives. Blends (mixtures) of polymers or copolymers with other alpha-olefins are also possible.

[0035] More preferably, it is a copolymer of ethylene with an α-olefin such as propylene or butene-1. By using the above, it is possible to incorporate short or long chain branches to a certain extent, which is the advantage of the high yield of the present invention. It is further advantageous to provide a raw yarn having a shrinkage ratio, and even if it is an ethylene homopolymer, Any material that satisfies the physical properties of the invention can be used.

[0036] The polyethylene resin has a weight average molecular weight of 600, which allows for melt spinning. 000 g / mol or less, more specifically 80,000 to 600,000 g / mol. Ugh.

[0037] In one embodiment of the present invention, the polyethylene raw yarn has a molecular weight distribution of more than 5 and less than 9. The molecular weight may be, more preferably, 6 to 8, and even more preferably, 6.5 to 7.5. The molecular weight distribution is the ratio of the weight average molecular weight (Mw) to the number average molecular weight (Mn) (Mw / Mn) and is known as the polydispersity index or molecular weight distribution index. It is also called the melting point diameter (MWD). The number of micro-injections (MI) is 0.3 to 6 g / 10 min, and more preferably 0.4 to 3 g / 10 min. It is possible.

[0038] As long as all of the above physical properties are satisfied, the flowability of the molten material during melt extrusion of the raw yarn is good, and the heat separation is easy. The process is ensured by preventing the occurrence of loose threads and preventing thread breakage during drawing, resulting in a uniform It is possible to manufacture raw yarn with the desired physical properties, and the shrinkage rate is 2.5% or less while still achieving the desired high strength. It is possible to provide a raw yarn having the above structure.

[0039] In addition, the density is 0.93 to 0.97 g / cm 3 , more preferably 0.941 to 0.965 g / cm 3 and the molecular weight distribution is in the range of more than 5 and less than 9. By using DPE, the crystallinity is increased to 65-85%, more preferably 70%, by melt spinning. The crystallinity of the polyethylene raw yarn can be measured by X-ray diffraction. During crystallinity analysis using a random analyzer, this can be derived along with the crystallite size.

[0040] In one embodiment, the raw yarn has a circular cross section, although the cross-sectional shape is not limited thereto. In addition, it may be that a twist or the like has been formed.

[0041] In one embodiment, the polyethylene raw yarn of the present invention has 40 to 500 continuous filaments (co The multifilament yarn may be a bundle of continuous filaments. Each of the fibers may have a fineness of 1 to 3 denier, and the polyethylene raw yarn is In the above range, the raw fabric is light and durable. This makes it possible to provide a base material having excellent properties.

[0042] Hereinafter, a method for producing a polyethylene raw yarn according to one embodiment of the present invention will be specifically described. The polyethylene fiber of the present invention has a small angle X-ray scattering (SAXS) scattering vector of 0 to 0.04 Å. -1 The highest point A of the intensity peak and the scattering vector 0.05~ 0.08Å -1 Ratio of the intensity peak generated at point A to the highest point B (A / B) If the physical properties of 16 or more and shrinkage rate of 2.5% or more are satisfied, there are no restrictions on the manufacturing method. The present invention is not intended to be limiting, but rather is intended to describe one embodiment.

[0043] A method for producing a raw yarn according to one embodiment of the present invention includes the steps of: The melt index (MI) measured at 190℃ and 2.16 kg is 0.3 to 6 g / 10 min. The polyethylene chips having a molecular weight distribution of more than 5 and less than 9 are melted to produce a polyethylene melt. Obtaining a melt; Spinning the polyethylene melt through a die having a plurality of nozzle holes. and, A plurality of fibrils are formed when the polyethylene melt is discharged from the nozzle hole. allowing the lament to cool; and The cooled filaments are then bundled together to form a multifilament yarn. Tep and The multifilament yarn is stretched at a total stretch ratio of 5 to 20 times and heat-set. Steps to do this: winding the drawn and heat-set multifilament yarn; may include:

[0044] Each step will be described in detail. First, polyethylene in the form of chips is is fed into an extruder 100 and melted to obtain a polyethylene melt.

[0045] The polyethylene chips may have a polydispersity index (PDI) of greater than 5 and less than or equal to 9. It has a melt index (MI) of 0.3 to 6 g / 10 min. 00 g / mol or less, more specifically 80,000 to 600,000 g / mol, preferably is 100,000 to 500,000 g / mol, more preferably 200,000 to 400, The weight average molecular weight (Mw) of the polymer may be in the range of 10,000 g / mol. In the range, it is possible to produce high-strength raw yarn, specifically, yarn having a tensile strength of 10 g / d or more. The weight average molecular weight (Mw) is 600,000 g / If the melt viscosity is too high, exceeding 1000 mol, the spinning equipment will be overloaded due to the high melt viscosity. As a result, the process is not properly controlled, and it is difficult to ensure the excellent physical properties of the raw yarn. Therefore, the polyethylene chips preferably have a molecular weight of 600,000 g / mol or less. More specifically, it is 80,000 to 600,000 g / mol, preferably 100,000 to 5 00,000 g / mol, more preferably 200,000 to 400,000 g / mol. It is good to have a weight average molecular weight (Mw).

[0046] The molten polyethylene is conveyed through a nozzle by a screw in the extruder, The extrusion is performed through a plurality of holes formed in the die. The number of holes in the die is determined by the manufacturing method. It is determined according to the DPF (Denier Per Filament) and fineness of the raw yarn. For example, When producing raw yarn having a total fineness of 75 denier, the spinneret has 20 to 75 holes. In the case of producing a raw yarn having a total fineness of 450 denier, The gold may have 90 to 450 holes, preferably 100 to 400 holes.

[0047] The melting process in the extruder and the extrusion process through the die are The melting point can be changed depending on the melting point. For example, the melting point is 150 to 315°C. The reaction may be carried out at a temperature of preferably 220 to 300° C., more preferably 250 to 290° C. That is, the temperature of the extruder and the die is 150 to 315°C, preferably 220 to 300°C, more preferably It is preferable to maintain the temperature at 250 to 290°C.

[0048] When the spinning temperature is less than 150° C., the polyethylene is homogeneously dispersed due to the low spinning temperature. Since it does not melt at 315°C, spinning may be difficult. In this case, the polyethylene may be thermally decomposed, and the desired strength may not be achieved. do.

[0049] The ratio (L / D) of the hole length L to the hole diameter D in the die is 3 to 40. If the L / D ratio is less than 3, die swell may occur during melt extrusion. This makes it difficult to control the elastic behavior of the polyethylene, resulting in poor spinnability. When L / D exceeds 40, necking of the molten polyethylene passing through the nozzle occurs. In addition to thread breakage due to the ink-threading phenomenon, non-uniform discharge due to pressure drop can occur.

[0050] The molten polyethylene is extruded from the holes in the spinneret, and the difference between the spinning temperature and room temperature causes the polyethylene to melt. The polyethylene begins to solidify, forming a semi-solid filament. In this case, we will not only use semi-solidified filaments, but also completely solidified filaments. Both are referred to as "filaments."

[0051] The filaments are cooled in a cooling zone (or "quenching zone"). The filament is cooled by air cooling. It is possible.

[0052] The filament cooling in the cooling section uses cooling air with a speed of 0.2 to 1 m / sec. It is preferable that the cooling temperature is 15 to 40°C. If the temperature is less than 100° C., the elongation will be insufficient due to supercooling, and yarn breakage may occur during the drawing process. If the cooling temperature exceeds 40°C, the fineness between the filaments may increase due to non-uniform solidification. The deviation becomes large and yarn breakage may occur during the drawing process.

[0053] In addition, by performing multi-stage cooling in the cooling section, crystallization can be performed more uniformly. It is possible to do so.

[0054] More specifically, the cooling section is divided into three or more sections. For example, three cooling sections In this case, the temperature is designed to gradually decrease from the first cooling section to the third cooling section. Specifically, the first cooling section is set to a temperature of 40 to 80° C. The second cooling section can be set to 30 to 50°C, and the third cooling section can be set to 15 to 30°C.

[0055] In addition, by setting the wind speed in the first cooling section to the highest possible level, the surface of the fibers becomes smoother. Specifically, the first cooling section is a cooling section having a wind speed of 0.8 to 1 m / sec. The temperature is cooled to 40-80°C using wind, and the second cooling section is at a speed of 0.4-0.6 m / s The temperature was cooled to 30 to 50°C using cooling air with a wind speed of 0.2 to 1.5 kPa. The temperature is cooled to 15~30℃ using cooling air with a speed of 0.5m / sec. By adjusting the conditions in this way, the crystallinity becomes higher and the surface becomes smoother. The raw yarn can be produced.

[0056] Next, the cooled and completely solidified filaments are bundled by a bundler to form a multi-filament filament. Form a lament.

[0057] The polyethylene yarn of the present invention may be produced by a direct spin-draw (DSD) process. That is, the multifilament is directly drawn into a multi-stage drawing section including a plurality of godet roller sections. The wire is then stretched in multiple stages at a total stretch ratio of 5 to 20 times, preferably 8 to 15 times. The wire can be wound onto the shank.

[0058] As an example, the drawing step using a plurality of godet rollers is a multi-stage drawing step having four or more stages. Preferably, the stretching step is carried out using a plurality of godet rollers. In the case of the multistage stretching, the stretching may be performed in 4 stages or more and 20 stages or less. In this case, rapid stretching occurs at each section of the godet roller, which causes fuzzing during the production of filament yarn. The frequency of breakage increases, the initial modulus increases, and the raw fabric may become excessively stiff. When the multi-stage drawing is performed in 20 stages or more, the friction between the filament yarn and the godet roller increases. This can increase the strain and cause filament damage and breakage.

[0059] In addition, it has a polydispersity index (PDI) of more than 5 and less than 9, and a melting index of 0.3 to 6 g / 10 min. Even if a polyethylene chip having a melt index (MI) of 190° C. is used, the present invention If the conditions of the stretch ratio, stretch temperature, and number of stages are not satisfied, the desired physical properties may not be obtained. For example, the maximum stretching temperature is 100 to 150° C. It is preferable that the total stretching ratio is 5 to 20 times, and multi-stage stretching is performed in 4 or more stages. The maximum drawing temperature means the highest temperature in the drawing section, and the total drawing ratio is , refers to the final draw ratio of the fiber after the final draw compared to the fiber before drawing.

[0060] For example, the multi-stage stretching is performed using a plurality of godet rollers in four or more stages, more specifically, four stages. The drawing may be performed in a multi-stage drawing of 10 stages or more and 20 stages or less. The temperature of the first godet roller GR1 among the GRn can be 50 to 80°C. The temperature of the last godet roller GRn may be 100 to 150° C. and the remaining godet rollers except for the last godet roller section (GR1, GRn) The temperature of the godet roller is set to be equal to or higher than that of the godet roller of the previous stage. The temperature of the last godet roller portion GRn can be determined by the temperature of the godet roller portion of the immediately preceding stage. It can be set to the same temperature as or higher than that, but slightly lower. It is also possible that this will happen.

[0061] In addition, during multi-stage stretching, by giving a shrinkage stretch (relaxation) of 1 to 5% in the last stretching section, This makes it possible to provide yarn with even greater durability.

[0062] To give a more specific example, the multi-stage drawing is composed of a total of four godet roller sections. The first godet roller section is stretched 2 to 4 times at 50 to 80°C, and the second godet roller section is stretched 2 to 4 times at 50 to 80°C. The dead roller section stretches the material 3 to 10 times at 70 to 100°C, and the third godet roller section stretches the material 3 to 10 times at 80 to 1 1.1 to 3 times stretching at 10℃, 1 to 5% shrinkage at 100 to 150℃ at the 4th godet roller The first godet roller portion may be configured to perform shrinking and stretching (relaxation). Each of the fourth godet roller portions may be formed of a plurality of godet rollers. For example, it may be formed of two or more godet rollers, more specifically, two to ten godet rollers. do.

[0063] Alternatively, the multifilament may be wound as an undrawn yarn, and then the undrawn yarn may be wound. By drawing the yarn, the polyethylene raw yarn of the present invention can be produced. The polyethylene raw yarn of the present invention is a polyethylene raw yarn that is first produced by melt spinning polyethylene into an undrawn yarn. It may also be produced in a two-stage process in which the undrawn yarn is then drawn.

[0064] If the total draw ratio applied in the drawing process is less than 5, the final polyethylene raw yarn The crystallinity of the polymer cannot be more than 65%, and the A / B ratio of small angle X-ray scattering (SAXS) is 1 6 or more and the shrinkage rate of 2.5% or more. There is a risk of pilling being induced on the rolls produced from the raw yarn.

[0065] On the other hand, if the total stretch ratio exceeds 20 times, thread breakage may occur. The strength of the polyethylene yarn finally obtained is not adequate, and the weaving property of the polyethylene yarn is poor. Not only is this not good, but the fabric made from it is too stiff, which makes it difficult for users to use. It can be inconvenient.

[0066] The linear speed of the first godet roller GR1, which determines the spinning speed of the melt spinning of the present invention, is determined. When the multi-stage stretching section is used, the total stretching ratio is 5 to 20 times, preferably 8 to 15 times. The linear speed of the remaining godet rollers is appropriately determined so that it can be applied to the multifilament. can be.

[0067] The multi-stage drawing section simultaneously performs multi-stage drawing and heat setting of the multifilament. The multi-stage drawn multifilament is wound on a winder, and the fiber of the present invention is A clear polyethylene yarn is completed.

[0068] The polyethylene fiber of the present invention produced as described above has a high cut resistance and is therefore suitable for use in a storage container. It can be used in the manufacture of protective products (e.g., protective gloves, underwear, bags, etc.).

[0069] The present invention will be described in more detail below based on examples and comparative examples. The examples and comparative examples are merely illustrative examples for explaining the present invention in more detail, and are not intended to limit the scope of the present invention. However, the present invention is not limited by the following examples and comparative examples. The physical properties were measured as follows.

[0070] <Weight average molecular weight (Mw) (g / mol) and polydispersity index (PDI)> The polyethylene yarn was completely dissolved in the following solvent and then subjected to the following gel permeation chromatography: The weight average molecular weight (Mw) and polydispersity index (PDI) of the polyethylene raw yarn were measured using gel permeation chromatography (GPC). The molecular weight distribution (Mw / Mn:PDI) was calculated for each.

[0071] -Analytical equipment: Tosoh HLC-8321GPC / HT -Column: PLgel guard (7.5 x 50 mm) + 2 x PLgel mixed-B (7.5 x 30 0mm) -Column temperature: 160°C -Solvent: Trichlorobenzene (TCB) + 0.04 wt.% dibutylhydroxytoluene (BHT)(after drying with 0.1% CaCl2) -Injector and detector temperature: 160℃ -Detector: RI Detector -Flow rate: 1.0ml / min -Injection volume: 300mL -Sample concentration: 1.5mg / mL -Standard sample: polystyrene

[0072] <Tensile strength (g / d), initial modulus (g / d), and elongation (%)> According to ASTM D2256 method, Instron Engineering Corp. (Ca The deformation-stress curve of the polyethylene yarn was obtained using a universal tensile tester (Nonton, Massachusetts). The length of the sample was 250 mm, the tensile speed was 300 mm / min, and the initial load ( The load was set to 0.05 g / d. The tensile strength was calculated from the stress and elongation at the breaking point. The degree of elongation (g / d) and the elongation rate (%) are calculated, and the maximum gradient of the curve near the origin is given. The initial modulus (g / d) was calculated from the tangent line of the yarn. After five measurements were taken for each yarn, The average value was calculated.

[0073] <Crystallization of raw yarn> XRD equipment (X-ray Diffractometer) [Manufacturer: PANalytical, Model name: EM The crystallinity of polyethylene yarn was measured using a 100% cellulose ether. The raw fiber was cut to prepare a sample having a length of 2.5 cm. After the specimen was fixed in a holder, measurements were performed under the following conditions.

[0074] Light source (X-ray Source):Cu-Kα radiation Power: 45KV x 25mA Mode: Continuous scan mode Scan angle range: 10~40° Scan speed: 0.1° / sec

[0075] <Melting index> Measured according to ASTM D1238 at 190°C and 2.16 kg.

[0076] <Small angle X-ray scattering> XRD equipment (X-ray Diffractometer) [Manufacturer: PANalytical, Model name: EM Measurements were performed using PYREAN.

[0077] From the measured graph, the scattering vector is 0 to 0.04 Å. -1 The peak intensity (In The highest point A of the tensile peak and the scattering vector 0.05-0.08Å -1 Peaks occurring at The ratio (A / B) of the intensity peak to the highest point B was calculated.

[0078] Light source (X-ray Source):Cu-Kα radiation Power: 45KV x 40mA Mode: Continuous scan mode Scan angle range: 0.1~2.0° Scan speed: 0.01° / sec

[0079] <Shrinkage rate> The polyethylene yarn was cut to obtain a sample of 70 cm length, and both ends of the sample were The display was placed at a distance of 10 cm from each other (i.e., the distance between the display points = 50 cm m). Next, the sample was hung on a jig so that no load was applied to it, and the sample was placed in a hot air circulatory system. The sample was heated at 100°C for 30 minutes in a circular furnace. After that, the sample was taken out of the furnace. After the sample was taken out and allowed to cool slowly to room temperature, the distance between the indicated points was measured. The dry heat shrinkage of the polyethylene yarn at 100°C was calculated using this.

[0080] Dry heat shrinkage rate (%)=[(L0-L1) / L0]×100 (Here, L0 is the distance between the display points before heating (i.e., 50 cm), and L1 is , the distance between the marked points after heating.)

[0081] The dry heat shrinkage values ​​obtained from the two tests were averaged.

[0082] [Example 1] <Production of polyethylene yarn> We produced polyethylene yarn containing 240 filaments and a total fineness of 500 denier. Ta.

[0083] Specifically, 0.962 g / cm 3 Density: 340,000g / mol weight average molecular weight (Mw), molecular weight distribution of 7.5, and melt index (MI at 1 Polyethylene chips having a temperature of 90°C were fed into the extruder and melted. The resin was extruded through a die with 240 holes. The diameter of the holes in the die The ratio of the hole length L to D (L / D) was 6. The temperature of the die was 260°C. .

[0084] The filament formed by extruding from the nozzle hole of the die is divided into three sections. The first cooling section was cooled by cooling air with a speed of 0.9 m / sec. In the second cooling section, the temperature is reduced to 35°C by cooling air with a speed of 0.5 m / sec. In the third cooling section, the material was finally cooled to 25°C by cooling air with a speed of 0.4 m / sec. After cooling, the fibers were bundled into a multifilament yarn by a bundler.

[0085] The multifilament yarn then moved to a drawing section, which consisted of four sections: It is made up of a multi-stage extension section, a total of four godet roller sections, and each godet roller section is The first godet roller section has a maximum temperature of 80°C. The maximum temperature of the second godet roller is 90°C, the maximum temperature of the third godet roller is 95°C, The maximum temperature of the fourth godet roller was set at 120°C, and the stretch ratio was 100%. 2x extension at the first godet roller, 3x extension at the second godet roller, 4x extension at the third godet roller In the fourth godet roller section, the paper is stretched 1.4 times, and in the fourth godet roller section, the paper is stretched 1.4 times. The stretched part is stretched by 4% compared to the rolled part, and the stretched part is stretched by 8 times in total. Fixed.

[0086] The drawn multifilament yarn was then wound on a winder. was 0.8g / d.

[0087] The physical properties of the produced raw yarn were measured and are shown in Table 1 below. In addition, small angle X-ray scattering (SAXS) The scattering vectors of small angle X-ray scattering (SAXS) were measured and shown in Figure 1. -1 The highest point A of the intensity peak and the scattering vector 0.05~0 .08Å -1 Ratio of the intensity peak generated at point A to the highest point B (A / B) was 28.

[0088] [Example 2] <Production of polyethylene yarn> In the above Example 1, the total stretch ratio was adjusted to 11 times. A raw yarn was produced in the same manner as in Example 1.

[0089] The physical properties of the produced raw yarn were measured and are shown in Table 1 below. In addition, small angle X-ray scattering (SAXS) The small angle X-ray scattering (SAXS) scattering vectors are 0 to 0.04 Å. -1 The highest point A of the peak intensity (Intensity Peak) and the scattering vector 0.05~0. 08Å -1 The ratio (A / B) of the intensity peak generated at the highest point B is, The figure was 27.5.

[0090] [Example 3] <Production of polyethylene yarn> In the above Example 1, the total stretch ratio was adjusted to 13 times. A raw yarn was produced in the same manner as in Example 1.

[0091] The physical properties of the produced raw yarn were measured and are shown in Table 1 below. In addition, small angle X-ray scattering (SAXS) The small angle X-ray scattering (SAXS) scattering vectors are 0 to 0.04 Å. -1 The highest point A of the peak intensity (Intensity Peak) and the scattering vector 0.05~0. 08Å -1 The ratio (A / B) of the intensity peak generated at the highest point B is, The figure was 22.6.

[0092] [Example 4] <Production of polyethylene yarn> In the above Example 1, 0.961 g / cm 3 density of 340,000 g / mol weight average molecular weight (Mw), molecular weight distribution of 5.5, and melt index ( A polyethylene chip with a stretch ratio of 13 was used. The yarn was produced in the same manner as in Example 1, except that the yarn thickness was adjusted to 100 μm.

[0093] The physical properties of the produced yarn were measured and are shown in Table 1 below. Small angle X-ray scattering (SAXS) Vector 0~0.04Å -1 The highest point A of the intensity peak that occurs at Scattering vector 0.05~0.08Å -1 The maximum intensity peak that occurs at The ratio to high point B (A / B) was 16.

[0094] [Example 5] <Production of polyethylene yarn> In the above Example 1, 0.961 g / cm 3 density of 340,000 g / mol It has a weight average molecular weight (Mw), a molecular weight distribution of 8, and a melt index (MI) of 1.6 g / 10 min. A polyethylene chip having a stretch ratio of 13 was used. The yarn was produced in the same manner as in Example 1, except for the cutting.

[0095] The physical properties of the produced raw yarn were measured and are shown in Table 1 below. Small angle X-ray scattering (SAXS) Vector 0~0.04Å -1 The highest point A of the intensity peak that occurs at Scattering vector 0.05~0.08Å -1 The maximum intensity peak that occurs at The ratio to high point B (A / B) was 18.

[0096] [Comparative Example 1] <Production of polyethylene yarn> In the above Example 1, 0.960 g / cm 3 density of 340,000 g / mol It has a weight average molecular weight (Mw), a molecular weight distribution of 3, and a melt index (MI) of 1.5 g / 10 min. A polyethylene chip with a stretch ratio of 11 was used. The yarn was produced in the same manner as in Example 1, except for the cutting.

[0097] The physical properties of the produced raw yarn were measured and are shown in Table 1 below. In addition, small angle X-ray scattering (SAXS) The small angle X-ray scattering (SAXS) scattering vectors are 0 to 0.04 Å. -1 The highest point A of the intensity peak and the scattering vector 0.05~ 0.08Å -1 The ratio of the intensity peak generated at the highest point B to the intensity peak (A / B) was 15.

[0098] [Table 1]

[0099] Although the present invention has been described above with reference to specific and limited embodiments and drawings, The above examples are merely provided for a more general understanding of the present invention. It is understood by those skilled in the art that the present invention is not limited to the above. Many modifications and variations are possible in light of the above teachings.

[0100] Therefore, the spirit of the present invention should not be limited to the described embodiments, but should be understood to be within the scope of the following claims. Not only the scope of the claims described above, but also equivalent or equivalent modifications to the scope of the claims All of these can be said to fall within the scope of the concept of the present invention.

Claims

1. Small angle X-ray scattering (SAXS) scattering vector 0-0.04 Å －１ Peak intensity occurring at (Intensity Peak) maximum point A and scattering vector 0.05-0.08 Å －１ Occurs in The ratio (A / B) of the peak intensity (Intensity Peak) to the highest point B is 16 or more, and the shrinkage rate A polyethylene raw yarn having a molecular weight of 2.5% or more.

2. The raw yarn has a melt index (MI) of 0.3 to 6 g / mol / L measured at 190° C. and 2.16 kg. The polyethylene raw yarn according to claim 1, having a tenacity of 10 min.

3. The polyethylene raw yarn according to claim 1, wherein the raw yarn has a molecular weight distribution of more than 5 and less than 9.

4. The polyethylene yarn according to claim 1, wherein the yarn has a crystallinity of 65 to 85%.

5. The polyethylene raw yarn according to claim 1, wherein the raw yarn has a melting temperature of 130 to 140° C. 。

6. The raw yarn has a density of 0.93 to 0.97 g / cm ３ The polyethylene of claim 1, Len raw yarn.

7. The melt index (MI) measured at 190°C and 2.16 kg is 0.3 to 6 g / 10 min. The polyethylene chips having a molecular weight distribution of more than 5 and less than 9 are melted to obtain a polyethylene melt. Obtaining a melt; Spinning the polyethylene melt through a die having a plurality of nozzle holes. and, A plurality of fibrils are formed when the polyethylene melt is discharged from the nozzle hole. allowing the lament to cool; and The cooled filaments are then bundled together to form a multifilament yarn. Tep and The multifilament yarn is stretched at a total stretch ratio of 5 to 20 times and heat-set. Steps to do this: winding the drawn and heat-set multifilament yarn; and a small angle X-ray scattering (SAXS) scattering vector of 0 to 0.04 Å. －１ The peak that occurs at The highest point A of the peak intensity and the scattering vector 0.05 to 0.08 Å －１ At The ratio (A / B) of the intensity peak generated to the highest point B is 16 or more. A method for producing polyethylene raw yarn, wherein the shrinkage rate is 2.5% or more.

8. The polyethylene melt has a spinning temperature of 220 to 300° C. A method for producing ethylene yarn.

9. The polyethylene according to claim 7, wherein the maximum stretching temperature is 100 to 150° C. A method for manufacturing raw yarn.

10. 8. The method for producing polyethylene raw yarn according to claim 7, wherein the drawing step is performed by multi-stage drawing. method.

11. The multi-stage drawing is performed using a plurality of godet rollers. Method for producing polyethylene yarn.

12. The multistage drawing is performed in 4 stages or more and 20 stages or less of the polyimide film according to claim 10. A method for producing ethylene yarn.

13. The godet rollers are set at a temperature of 50 to 150° C. The temperature of the first godet roller among the plurality of godet rollers is 50 to 80° C. 、 The temperature of the last godet roller among the plurality of godet roller sections is 100 to 150° C. and The godet rollers excluding the first and last godet rollers among the plurality of godet rollers The temperature of each roller is the same as that of the godet roller located in the previous stage. The method for producing polyethylene yarn according to claim 10, characterized in that the yield is 100% or higher. Construction method.

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