POLYMERIC FIBER PRODUCTION METHOD

Abstract

The invention relates to a fiber production method that enables the modification of fibers during the production of mono and multifilament yarns from molten polymers, thereby improving their performance and function. The invention allows for the efficient regulation of polymer chain orientations, enabling the production of fibers exhibiting high mechanical performance and functional properties from various thermoplastic polymers, including low-density and recycled polymers.

Description

TARIFF POLYMERIC FIBER PRODUCTION METHOD Technical Area The invention relates to a fiber production method that enables the modification of fibers during the production of mono and multifilament yarns from molten polymers, thereby improving their performance and function. Previous Technique In the current state of the art, during the production of polymer fibers from melt, the fibers sprayed from the nozzle are passed through an oil-based liquid bath to improve their mechanical performance. To effectively regulate mechanical performance, high winding speeds exceeding 2000 m / min are utilized, requiring expensive equipment. Achieving sufficient mechanical performance necessitates the selection of high-density or high-molecular-weight polymers, and recycled polymers cannot be effectively utilized. The use of oil-based liquid baths requires workers to wear protective clothing, intensive cleaning around the production line, and costly waste control methods. Fibers with improved mechanical performance require further processing after winding to acquire functional properties. This increases both the complexity of the production process and consequently the production costs, and also limits the effects because the entire fiber surface cannot be effectively processed after winding. Applications for obtaining polyester fibers exhibiting high crystallinity and regular chain orientation by utilizing an oil-based liquid bath are described in documents US5149480A and US5733653A. Some further developments in this field are described in document US2016010244Al and in the studies conducted by Yoon et al. (2017) [1], Avci et al. (2015) [2], Najafi et al. (2015) [3], Avci et al. (2015) [4], Avci et al. (2013) [5], Chen et al. (2009) [6]. Several solutions for using multiple liquid baths in the production of polymer fibers from melt are also known in the field. Document US6238608B1 describes a method in which the fibers obtained from the melt are passed through two successive water baths for cooling purposes. Document CNI06521688A describes a method where melt-generated fibers are passed through a cooling bath and then a stretching bath, respectively. Both documents also describe the use of water-based baths. Although not related to yarn production, document WO2020185862A1 describes impregnation of melt-generated fibers with matrix-forming polymers and polymer components by passing them through two consecutive baths. It is noted that the baths can have different compositions and temperatures. Documents DE102019116512A1, US4909976A, and US8188206B2 describe solutions where melt-generated fibers are processed in a gaseous environment before the liquid bath. Purposes of the Invention The aim of this invention is to develop a method for imparting mechanical and different functional properties to polymer fibers during their production from melt. Another objective of this invention is to develop a method that enables the mechanical and functional properties of fibers to be imparted in a single step, i.e., before the fibers exiting the nozzle are wound. Another aim of this invention is to develop a method that allows the use of low-density polymers or polymers derived from recycled materials. Another aim of this invention is to develop a method that allows high mechanical performance to be achieved with low winding speeds. Another aim of this invention is to develop a method that enables the use of environmentally friendly, water-based solutions with minimized environmental impact and effects on worker health. Detailed Description of the Invention The methods used to achieve the objectives of this invention are explained in the attached figures. Figure 1 is a schematic view of a device for implementing the method described in the invention. The parts shown in the figures are individually numbered, and their corresponding numbers are given below. Level 1 2. First improvement zone 3. Second improvement zone 4. Sarici 5. Godet 6. Funnel 7. Extruder The invention's fiber production method, which enables the modification of fibers to improve their performance and function during the production of mono and multifilament yarns from molten polymers, basically includes the steps of preparing the thermoplastic polymer melt, spraying the melt from a nozzle (1) to form fibers, passing the fibers through multiple improvement zones and winding the improved fibers. Fibers sprayed in molten form from the nozzle (1) are first passed through one or more primary conditioning zones (2). When the fibers emerge from the primary conditioning zone (2), they are only partially solidified. For this reason, the temperature of the primary conditioning zone (2) is above the crystallization temperature but below the degradation temperature of the polymer concerned. The temperature of the primary conditioning zone (2) is preferably 10 °C above the softening temperature of the polymer concerned. Fibers that are only partially solidified are passed through a second improvement zone (3) where they solidify after the first improvement zone (2). In a preferred application of the invention, the viscosity of the medium in the first improvement zone (2) is lower than the viscosity of the medium in the second improvement zone (3). The nozzle (1) is fed by an extruder (7) consisting of a screw and barrel, into which the granular polymer material is loaded via a funnel (6) and the granules taken from the funnel (6) are heated gradually. The pressure provided by the extruder (7) can be used to spray the molten polymer from the nozzle (1), or a separate pump can be located before the nozzle (1). Fibers passing through the healing zones are wound by one or more winders (4). The winder (4) also helps to regulate the speed, tension and torsion to which the fibers are subjected as they pass through the healing zones. This speed, tension and torsion can be regulated by the winder (4) as well as by godets (5) located between the healing zones and the winder (4) or between the healing zones. In the first curing zone (2), a medium consisting of dry air, nitrogen, argon in gaseous form with a viscosity of 10⁶-10⁲ mPa⁻¹, or aqueous solutions, aqueous mixtures, aqueous emulsions and suspensions in liquid form with a viscosity of 1-100 mPa⁻¹ is used. In the first curing zone (2), the polymer chains are not fully immobilized because the polymer only partially solidifies. Depending on the viscosity of the medium, the drift and shear forces can effectively adjust the orientation of the polymer chains and thus the mechanical properties of the fibers. In the second improvement zone (3), a liquid medium with a viscosity of 0.3 - 2 mPa-s is used. The temperature of the second improvement zone (3) is between room temperature and 150 °C, preferably between 50 - 100 °C. The fibers are exposed to the second improvement zone for 10'2 - 10'1 seconds. In the second improvement zone (3), the solidification of the polymers is completed, optimizing the internal structure of the fibers and improving their mechanical properties. In the second improvement zone (3), at the same time as improving the mechanical properties of the fibers, various functional properties can also be imparted to the fibers, including flame retardancy, improved adhesion, antibacterial or antiviral effect, odor, fullness, ultraviolet radiation resistance, color, hydrophilicity, degradation, and conductivity. These functional properties are determined by the selection of the medium content. In the second improvement zone (3), a medium consisting preferably of aqueous solutions, aqueous mixtures, aqueous emulsions and suspensions is used. In one application of the invention, the fibers may also pass through one or more third improvement zones where they are processed while in a solidified state after the second improvement zone (3). The temperature of the third healing zone is between room temperature and 150 °C, preferably between 50 and 100 °C. The third healing zone preferably consists of a liquid bath. The exposure time of the fibers to the third healing zone depends on the bath length and the fiber winding speed. The interaction length of the fibers with the bath is between 30 cm and 300 cm, preferably between 50 cm and 100 cm. The bath content can be neutral, acidic, or basic depending on the new added property. The fiber winding speed should be between 250 m / min and 3000 m / min, preferably between 400 m / min and 1500 m / min. In the third improvement zone, while the mechanical and functional properties previously imparted to the fibers are preserved, new functional properties can be acquired and existing functional properties can be improved. The third improvement zone can also neutralize the pH value created by the effects of the previous improvement zones and remove residues. In the third treatment phase, a medium consisting preferably of aqueous solutions, aqueous mixtures, aqueous emulsions, and suspensions is used. Within the improvement zones, fiber properties, along with viscosity, can be controlled through variables such as temperature, content, pH, fiber path, and fiber speed. This invention enables the production of fibers from various thermoplastic polymers, primarily polyethylene, polypropylene, polyamide, and polyester. High molecular weight polymers are not required to achieve superior mechanical and functional properties, and recycled polymers can be utilized. Because the invention can be implemented at low winding speeds, it can be easily applied in conventional melt-based production lines. Furthermore, the use of an aqueous medium minimizes the environmental and worker health impacts of the production process. In a sample application of the invention, polyethylene fibers were passed through a first improvement zone (2) with low viscosity and a second improvement zone (3) with higher viscosity at a speed of 750 m / min. In the second improvement zone (3), an aqueous solution containing up to 10% by weight of Arabic gum (acacia gum) was used. With this application, fibers with high mechanical performance and high wettability and adhesion to the surface without any additional processing were obtained. The modulus of these fibers was measured as 1.4 GPa. In contrast, the modulus value obtained with the same polyethylene using conventional methods was measured as 262 MPa, while for similar polyethylene fibers mentioned in the literature, it was 100 5 The contact angle was found to be 37.8° in the fibers obtained with this application of the invention. In contrast, the contact angle was measured as 101.3° in the fibers produced using conventional methods. In another example application of the invention, polyethylene fibers were passed through a first improvement zone (2) with low viscosity and a second improvement zone (3) with higher viscosity at a speed of 1000 m / min. In the second improvement zone (3), an aqueous solution containing 1.5% by weight of organic phosphorus additive was used. With this application, fibers exhibiting high mechanical performance and high thermal resistance and flame retardancy without any additional processing were obtained. The modulus of these fibers was measured as 109 MPa. In contrast, the modulus value obtained with the same polyethylene using conventional methods was measured as 56 MPa. In the fibers obtained with this application of the invention, the LOI (limiting oxygen index) value was 21.5, and the heat release (pHRR - peak heat release rate) was measured as 1209 W / g as a result of the MCC (micro-combustion calorimeter) test. In contrast, fibers produced using traditional methods had an LOI value of 19.8 and a heat release of 1523 W / g as measured by the MCC test. Referanslar 1. Yoon, J. H., Avci, H., Najafı, M., Nasri, L., Hudson, S. M., & Kötek, R. (2017). Development of high-tenacity, high-modulus poly (ethylene terephthalate) filaments via a next generation wet-melt-spinning process. Polymer Engineering & Science, 57(2), 224-230. 2. Avci, H., Najafi, M., Kilic, A., & Kötek, R. (2015). Highly crystalline and oriented highstrength poly (ethylene terephthalate) fibers by using low molecular weight polymer. Journal of Applied Polymer Science, 132(45). 3. Najafi, M., Avci, H., & Kötek, R. (2015). High-performance filaments by melt spinning low viscosity nylon 6 using horizontal isothermal bath process. Polymer Engineering & Science, 55(11), 2457-2464. 4. Avci, H., Kötek, R., & Toliver, B. (2015). Controlling of threadline dynamics via a novel method to develop ultra-high performance polypropylene filaments. Polymer Engineering & Science, 55(2), 327-339. 5. Avci, H., Kötek, R., & Yoon, J. (2013). Developing an ecologically friendly isothermal bath to obtain a new class high-tenacity and high-modulus polypropylene fibers. Journal of materials science, 48(22), 7791-7804. 6. Chen, P., Afshari, M., Cuculo, J. A., & Kötek R. (2009). Direct formation and characterization of a unique precursor morphology in the melt-spinning of polyesters. Macromolecules, 42, 5437-5441. 7. Kim, J. W., & Lee, J. S. (2017). Effect of Heat Drawing Process on Mechanical Properties of Dry-Jet Wet Spun Fiber of Linear Low Density Polyethylene / Carbon Nanotube Composites. International Journal of Polymer Science, 2017. 8. Mezghani, K., Farooqui, M., Furquan, S., & Atieh, M. (2011). Influence of carbon nanotube (CNT) on the mechanical properties of LLDPE / CNT nanocomposite fibers. Materials Letters, 65(23-24), 3633-3635. 9. Coppola, B., Scarfato, P., Incarnato, L., & Di Maio, L. (2017). Morphology development and mechanical properties variation during cold-drawing of polyethylene-clay nanocomposite fibers. Polymers, 9(6), 235. 10. Kolgjini, B., Schoukens, G., Shehi, E., & Kiekens, P. (2013). Bending Behaviour of LLDPE Monofilaments Depending on Cold Drawing and Composition of the LLDPEs. Fibres & Textiles in Eastern Europe, (4 (100)), 23-30. 11. Cho, Η. H., Kim, Κ. Η., Ito, Η., & Kikutani, T. (2000). Fine structure and physical properties of polyethylene fibers in high-speed spinning. IL Effect of catalyst systems in linear low-density polyethylene. Journal of applied polymer science, ΊΊ(β\ 1195-1206.

Claims

9 REQUESTS 1. During the production of mono and multifilament yarns from molten polymers, the fibers... a fiber that allows its performance and functions to be modified for improvement is a production method, - The temperature of the fibers sprayed in molten form from the nozzle (1) is 5 of the relevant polymer. from the first healing zone which is 10 °C above the softening temperature (2) passing through, - The fibers then have a higher than the first improvement zone (2) Passing through the second improvement zone (3) with medium viscosity, - Fibers passed through the healing zones are wrapped with one or more wrappers (4) 10 hug It is characterized by including its steps.

2. A fiber production method as in Claim 1, and the first improvement zone (2) If the temperature is above the crystallization temperature of the polymer in question, degradation occurs. It is characterized by being below a certain temperature. 15 3. A fiber production method as in Claim 1, but only in a partially solidified state. a second improvement where the fibers solidify after the first improvement zone (2) It is characterized by passing through the region (3).

4. A fiber production method as in Claim 3, where the solidified fibers are produced in one or more parts. It is characterized by passing through more third improvement zones. 20 5. A fiber production method as in Claim 1, with the first improvement zone (2) and second improvement zone (3) aqueous solutions, aqueous mixtures, aqueous emulsions and It is characterized by being a liquid medium consisting of suspensions.

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