KR20220117936A - Manufacturing method of monofilament yarn using recycled nylon - Google Patents

Abstract

The present invention is to manufacture nylon monofilament yarn using recycled nylon obtained from defective products produced at the beginning and end of production in a manufacturing (production) process of nylon 6 (polyamide) and discarded due to non-compliance with the desired specifications because of unstable physical properties and defective products produced when troubles occur at process conditions or the like in a production process and discarded due to non-compliance with the desired specifications because of unstable physical properties. The method for manufacturing the monofilament yarn using recycled nylon comprises: a drying process of cutting, washing, and drying collected process defective products; a process of molding the defective products into recycled nylon chips while melting and filtering the defective products; and a process of manufacturing monofilament yarn by adding stearic acid metal salt to the recycled nylon chips and performing melt-spinning. The present invention is very advantageous in manufacturing higher quality nylon monofilament yarn for shoes, shoemaking, or chairs without deterioration of the physical properties of nylon adopting the recycled nylon obtained from the process-defective products as a raw material without a decrease in relative viscosity.

Description

Manufacturing method of monofilament yarn using recycled nylon {Manufacturing method of monofilament yarn using recycled nylon}

The present invention relates to a method for manufacturing a monofilament yarn using regenerated nylon, and specifically, to a method for manufacturing a monofilament yarn for shoes, shoes or a chair using regenerated nylon prepared from defective products in the discarded nylon 6 manufacturing process is about

Generally, nylon is a generic term for polyamide, and nylon yarn is shoes. It is used in shoes, women's stockings, military parachutes, body armor, firefighting suits, underwear, socks, etc., and furthermore, it is used in various fields such as tire cords and automobile parts.

recent shoes. The demand for monofilaments using recycled nylon 6 suitable for fabrics such as shoes and shoes is increasing as it is required to use recycled raw materials as a material for the purpose of using eco-friendly image marketing for shoe or chair manufacturing brands.

However, nylon products are manufactured by mixing with various other materials, and in order to reproduce at the raw material level of the material, difficult and complicated processes such as separation of the mixed material from the finished product are required, which is not advantageous from a commercial point of view. Although it is produced as products such as fishing nets and fishing lines, most of the fabrics for clothing are dyed, so it is difficult to use them as fabric yarns when recycling them. It is not suitable for use as a recycling material.

Although the prior art cannot be specifically exemplified in relation to the manufacture of monofilament yarns using nylon regenerated from waste nylon, as prior art related to the regeneration of waste nylon, for example, in Patent Document 1, polyamide regenerated resin, organic A modified vinyl aromatic graft copolymer obtained by graft polymerization of an aromatic vinyl monomer to a nanoclay rubber polymer by melt-kneading a reactive monomer having an organic peroxide, unsaturated carboxylic acid, or anhydride group to a graft copolymer and styrene Although a recycled polyamide nanocomposite composition containing an impact modifier is disclosed, it is not related to the technology of manufacturing monofilament yarn from regenerated nylon. Since additives are combined in the process, there is a problem in that the properties of the regenerated nylon chips do not show the properties of monofilaments suitable for fabrics such as shoes and shoes.

In addition, the step of washing the nylon waste fishing net in Patent Document 3 with industrial water containing pyridine and industrial detergent; depolymerizing by adding phosphoric acid to the cleaned nylon waste fishing net and heating it with high-temperature steam; adding potassium permanganate and activated carbon to the depolymerized lactam water, followed by oxidation and purification; filtering the oxidized depolymerized lactam water using a filter coated with diatomaceous earth; sequentially treating the filtered depolymerized lactam water with (-) ion exchange resin, (+) ion exchange resin, and (-) ion exchange resin; adding an aqueous sodium hydroxide solution to the filtered depolymerized lactam water, distilling at 100 to 150° C. and vacuum to remove moisture, followed by primary fractional distillation; Secondary or tertiary fractional distillation of the primary fractionated depolymerized lactam under the same conditions as the primary fractional distillation; And the prior art discloses a method for producing a recycled nylon chip, comprising the steps of polymerizing and molding the secondary or tertiary fractionated depolymerized lactam by mixing it with titanium dioxide, but the prior art decomposes the nylon fishing net to the monomer level and then polymerization And, there is a problem in that the process is complicated, such as going through a multi-step purification process.

The inventor of the present invention has completed the present invention by manufacturing a recycled monofilament yarn suitable for fabrics such as shoes and shoes by a simple method by recycling defective products generated in the process of manufacturing nylon 6 (polyamide).

US 10-0616723 B1 US 10-1749334 B1 US 10-1130461 B1

The problem to be solved in the present invention relates to the provision of a method for manufacturing a monofilament yarn using recycled nylon, and in detail, a monofilament yarn by recycling the defective products that are discarded due to non-standardization occurring in the manufacturing process of nylon 6 (Polyamide). It is intended to provide a method for manufacturing the.

In the above process, defective products are discarded due to unstable physical properties produced at the beginning and the end of production in the manufacturing (production) process such as nylon 6 (Polyamide). It means defective products that are discarded due to non-standard properties due to unstable physical properties. Hereinafter, in the present invention, they are defined as defective products.

As a means of solving the problem according to the present invention, the manufacturing method of monofilament yarn using recycled nylon is a first process of crushing and washing the collected nylon defective products, drying them, and selecting only the selected nylon defective products. The second process of forming a recycled nylon chip by melting and filtering at a certain temperature, and the third process of manufacturing a nylon monofilament yarn by mixing a metal stearic acid salt with the recycled nylon chip, melt spinning and extrusion molding with a spinning device consists of including

One embodiment according to the method for manufacturing a monofilament yarn using the regenerated nylon of the present invention is a). The first step of selecting only the selected nylon defective products by crushing, washing, and drying the collected nylon defective products, b). The second step and c) of melting the selected nylon defective products at 200 to 250° C., and compressing the melted material while filtering it with a filter of 100 to 250 mesh and forming into recycled nylon chips; and c). A preparation for manufacturing nylon monofilament yarn by mixing metal stearic acid salt with regenerated nylon chips at a concentration of 0.01 to 0.03 wt%, melt-spun in a spinning device under melt temperature conditions, extrusion-molded, and cooled, stretched and heat-set. It consists of three processes.

And as a means of solving another problem of the present invention, the monofilament yarn using recycled nylon is made of a recycled nylon monofilament yarn produced by the manufacturing method of the first to third steps, and is particularly suitable for shoes, shoemaking or Made of nylon monofilament yarn for chair,

The manufacturing method of monofilament yarn using regenerated nylon of the present invention has an effect of producing monofilament yarn for shoes, shoes or chairs while smoothly supplying regenerated nylon raw material to a spinning device without changing physical properties. Since high-quality recycled nylon monofilament yarns can be supplied, there is an advantage in that the supply of recycled raw materials can be increased in response to environmental demands.

Hereinafter, the present invention will be described in more detail in order to carry out the present invention, but the present invention is not limited by the contents described below.

The method for manufacturing a monofilament yarn using recycled nylon according to the present invention is a). The first step of selecting only the selected nylon defective products by crushing, washing, and drying the collected nylon defective products, b). The second process of melting the selected nylon defective product at a certain temperature, filtering the melt and compressing it to form a recycled nylon chip, and c). A third process of manufacturing a nylon monofilament yarn by mixing a metal stearic acid salt with the regenerated nylon chip, melt-spinning at a melting temperature condition in a spinning device, extrusion molding, cooling, stretching, and heat setting.

The first process according to the present invention is a process of selecting only selected nylon defective products, and the defective products generated in the manufacturing (production) process such as nylon 6 (Polyamide) are contaminated with foreign substances, etc., and have various shapes, such as recycled nylon In order to prevent the deterioration of the purity of the product and to perform the process smoothly, only the selected process defective products are selected by grinding and drying.

In general, the relative viscosity (R.V) of nylon 6, which is a raw material for monofilament yarns for shoes, shoes, or chairs, is preferably at a level of 3.2 to 3.4 to express the physical properties of the yarn, but the relative viscosity (R.V) of the defective products is 2.4 to 3.0. In order to further improve the quality of the recycled nylon yarn, only defective products with a relative viscosity (R.V) of 2.6 ~ 2.8 are selected and used as raw materials.

The second process according to the present invention is a process of heating and melting the selected defective products and molding them into regenerated nylon chips, melted in an extruder at 200 to 250° C. made by molding

The filtering of the melt is to remove foreign substances contained in the melt in order to prevent a decrease in the purity and a decrease in the relative viscosity of the regenerated nylon, and consists of filtering with a filter of 100 to 250 mesh.

The third process according to the present invention is a process of manufacturing a nylon monofilament yarn by melt-spinning a regenerated nylon chip in a spinning device, and consists of melt-spinning by blending a stearic acid metal salt with the regenerated nylon chip.

The metal stearic acid salt is formulated in a regenerated nylon chip to prevent a decrease in the relative viscosity of nylon during the melt spinning process and a monofilament yarn having a uniform viscosity is produced by smooth spinning of the melt, and the metal stearic acid salt is a regenerated nylon chip Calcium stearate or magnesium stearate is blended at a concentration of 0.01 to 0.03 wt%.

In the process of producing nylon monofilament yarn by melt spinning in the spinning device of the third step, the temperature of the cylinder of the spinning device is set from 250° C. to 290° C., and the temperature of the spinneret is set to 240 to 270° C. It consists of spinning, cooling by water cooling to 15 ~ 25 ℃ after extrusion spinning, stretching and heat setting.

The stretching and heat setting is performed by setting the first stretching roller speed to 34 to 40 m/min, the secondary stretching roller speed to 155 to 180 m/min, and the third stretching roller speed to 155 to 180 m/min, respectively, and the fourth The stretching roller speed consists of thermal setting by setting 150 to 175 m/min lower than the third, and the stretching ratio is determined by the speed ratio of the first to tertiary stretching rollers, and the stretching ratio is preferably set to 4.2 to 5.0 times.

In addition, in the stretching process, water treatment stretching is performed at 70 ~ 95 ℃ between the primary stretching roller and the secondary stretching roller, and dry heat treatment is performed at 130 ~ 190 ℃ by secondary heat treatment between the secondary stretching roller and the third stretching roller. It consists of dry heat setting between the 3rd and 4th rollers at a level of 130 ~ 190°C with a 3rd heat treatment.

And the nylon monofilament yarn produced by the first to third processes according to the present invention has physical properties of breaking strength of 6.0 to 7.5 gf/denier and elongation at break of 40 to 60%, Made of nylon monofilament yarn suitable for the application.

Claims (7)

a). The first process of shredding and washing the collected nylon defective products, drying them and selecting only the selected nylon defective products;
b). The second process of melting the selected nylon defective products at a certain temperature, filtering the melt, and compressing it to form a recycled nylon chip; and
c). A third process of manufacturing a nylon monofilament yarn by compounding a metal stearic acid salt with a regenerated nylon chip, melt-spun under a melting temperature condition in a spinning device, extrusion molding, cooling, stretching and heat setting A manufacturing method of monofilament yarn using recycled nylon. The method for manufacturing monofilament yarn using recycled nylon according to claim 1, wherein, in the first process, only defective products having a relative viscosity (R.V) of 2.6 to 2.8 are selected as the defective nylon in the first process. The method according to claim 2, The second process of manufacturing a monofilament yarn using recycled nylon, characterized in that the selected nylon defective product is melted at 200 ~ 250 ℃, and the melt is filtered with a filter of 100 ~ 250 mesh (mesh) Way. The method according to claim 3, wherein the metal stearic acid salt in the third step is calcium stearate or magnesium stearate, and is formulated in a concentration of 0.01 to 0.03 wt%. The method according to claim 4, In the third process, the cylinder temperature is set from 250 ° C to 290 ° C in the spinning device, and the temperature of the spinneret is set to 240 to 270 ° C. A method for manufacturing a monofilament yarn using recycled nylon, characterized in that cooling by water cooling, stretching and heat setting. A monofilament yarn using recycled nylon, characterized in that it is manufactured by the manufacturing method according to any one of claims 1 to 5. The monofilament yarn using recycled nylon according to claim 6, wherein the monofilament yarn using recycled nylon is a nylon monofilament yarn for fabrics for shoes, shoes, or chairs.