Then the solution is purified by filter the molten polymer is extruded at high pressure and constant rate through a spinneret into a. The high speed melt spinning of synthetic polymer fibers is provided with online zone heating and cooling by which the strand emerging from the spinneret is initially cooled to an optimum temperature above the glass transition point of the polymer, the maintained near that temperature for a period of time to promote development of desirable fiber properties such as crystallization and crystal. Besides the expressions of quench air temperature and quench air velocity for superfine denier filament spinning process have been established in this paper. Pdf modeling of melt electrospinning for semicrystalline. According to ziabicki 20, melt extruding from a spinneret. Electrospinning from a melt rather than a solution was patented by c. The effect of prehistory on elongational viscosity and on. Because of high melt viscosity, effective melt spinning is limited to polymers with intrinsic viscosities. There are three fundamental processes for the manufacture of synthetic fibres.
Textile spinning textile technology knowledge series volume ii texcoms textile solutions april 21, 2019. Nov 01, 1996 correlations between molecular weight and various viscosity characteristics are compared. George also gave an oral presentation in hawaii in 1979 on a related topic. In later works, the energy balance for the heat transfer was introduced into the model, and more. Melt spinning is an efficient platform to continuously produce fiber materials with multifunctional and novel properties at a large scale. For simplicity, we have considered a onedimensional crosssection averaged approximation for an isothermal system with no surface tension and air drag, with or without inertia. Online measurement of fiber diameter and temperature in the. Although melt processes have been used to produce bulk materials like cncpla, 19,20 cnfpla, 4 and cncpla.
Highspeed melt spinning of nanoparticlefilled high. Description of the process figure 1 presents a scheme of single. Study of structure development during melt spinning of. Crystallization i isothermal i melt spinning i melt structure i entanglement. Suspension dry spinning and rheological behavior of. Test spinning final parameters of the experiment are shown in. The mathematical model for melt spinning of doufas et al. Morphology development of polymer blend fibers along spinning. A drawback of these models is a purely newtonian rheological description of the melt and consequently neck formation is not predicted. Many kinds of synthetic textile fibers, like nylon, polyester, etc. In this work we investigate the use of an inhomogeneous structural model which explicitly takes into account flowinduced crystallization for representing the necking phenomenon in highspeed fiber spinning. There is a grid sieve at the base which permits only molten liquid to pass through.
When polymer granules or chips form the starting material for meltspinning, they are first dried and then melted in the extruder. Mathematical modelling of the pneumatic melt spinning of. Although melt processes have been used to produce bulk materials like cncpla, 19,20 cnfpla, 4 and. The nonwovens formation in the meltblown process ippt pan. Novel plasticized melt spinning process of polyacrylonitrile. Each hole produces an individual fiber, and the number of holes on a spinneret defines the number of fibers in the yarn. The high performance thermoplastic peek is solidified in the melt spinning process in a small distance and short time. An older publication of interest is studies on melt spinning. By the results, it was found that the viscosity profile along the spinline is the governing parameter of the stability for high draw ratio spinning.
One way it achieves this is by using a melt spinning line. An overview on models relating fiber diameter, process and solution parameters is given by schubert while a novel theory is suggested predicting not only the fiber diameter but also its distribution. Ultrafast calorimeter with controlled cooling up to 10,000 k. Fundamental equations 1d model, describing the axial distributions of diameter, velocity, temperature, stress and structures of the fiber during the melt spinning process, was proposed by ziabicki, kase et al. The melt spinning of pan fibers has been demonstrated with preliminary experiments. The clay and poss nanocomposites exhibited quite different melt spinning behaviors. Melt spinning, dry spinning and wet spinning method. When the advanced methods for rapid cooling of the molten metal are used, the alloy structure either crystallises in an atomiser assuming the form of powder, or it assumes the form of ribbons when solidifying on a spinning copper wheel. Norton in 1936 using an airblast to assist fiber formation. The science of fibre spinning and drawing, authora. Introduction in a recent paper 1, being an extension of similar considerations by ziabicki and tian 2, various mechanisms of necking in nonisothermal highspeed melt spinning were discussed.
Spinline crystallization of polyethylene terephthalate, in high speed fiber spinning, edited by a. Comput 19 ogata n, yamaguchi s, shimada n, lu g, iwata t, nakane k, et al. This type of spinning is used for polymers that are not decomposed or degraded by the temperatures necessary for extrusion. Based on the analysis of ziabicki 141d radially uniform models for the fic during. The melt spinning process involves preparation of a spinning fluid extrusion of the melt through spinneret into a cooling atmosphere and elongation of the extruded melt. It involves extruding polymer at an average massflow rate through a first group of orifices defined by specific location in the spinnerette, that is greater than the massflow rate of polymer through a second group of orifices also defined by location in the. The mechanisms leading to spinning failure during wet spinning and airgap spinning. Better than melt and dry spinning for temperature sensitive polymers. Novel plasticized melt spinning process of pan fibers. Melt spinning is a simpler and cheaper process than wet or dry spinning and is used industrially to produce materials like nylons and polyesters which are ubiquitous. The bifurcation phenomenon is controlled by stress. A viscoelastic description of the melt is incorporated in the. Pdf melt spinning of the fine peek filaments semantic scholar. The melted polymer fibers then passes through a cooling.
The process of melt spinning is designed to convert the polymer melt to a thin filament of uniform cross section on a continuing basis. In this paper, we describe a simple dry spinning process for green ceramic fibers. Us5034182a melt spinning process for polymeric filaments. Ziabicki 2 5, andrews 6 and kase 7 9 described scientifically mathematical models for spinning fibres from melted polymers. However, kinetics of oriented crystallization under such extreme conditions in fast melt spinning apparently has been adequately described by the phenomenological formula proposed by ziabicki, with the use of quiescent kinetic data. Ziabicki, and was analyzed quantitatively by the computer simulation by toriumi and konda 14. Meltspinning apparatus for polyester filaments celanese.
Chips of polymers are fed to a hopper which is heated. Consequently, towards the end of the 1950s, ziabicki published a series of papers concerning melt spinning in which the spinning process was analyzed mathematically as an engineering problem. Pdf the role of flowinduced crystallisation in melt. Kinetics of oriented crystallization of polymers in the.
Shooting superslowmotion movies hfr settings manual digital s. Cfd modeling of the melt spinning of poly ethylene. The better understanding of the formation and development of morphology of polymer blend fibers during melt spinning. Polyethylene terephthalate nanofiber made by ultramulti. Pdf melt spinning of the fine peek filaments semantic. Based on melt spinning dynamic model and theory, a basic model of superfine denier polyester multifilament was established. A meltspinning process for spinning polymeric filaments at a spinning speed controlled by a positive mechanical withdrawal means that increases the speed of the filaments to above 7,000 metersminute whereby a drawing and necking down of the filaments occur below the spinning pack, directing a gas into a zone extending from the spinning pack to a location between the spinning pack and the. A 25c decrease in the glass transition temperature, t. First, in spite of nonnewtonian viscosity of polymer melt having been known in the study of shear flow, the running filament in melt spinning has been assumed to be newtonian fluid. Therefore, the fine peek filaments in the fibre formation zone underwent a high deformation and.
Structurecontrolled bifurcation in mathematical modelling of. The dynamics of melt spinning processes has been studied by many research groups throughout the world during the last decades starting with early works of kase and matsuo 4 and ziabicki 10. Lower production rates than melt or dry spinning due to viscous drag. Fibre spinning is a process in which an extruded liquid polymer filament is continuously drawn and simultaneously solidified to form a continuous synthetic fibre. Jan 01, 1998 polymer science volume 8 number 12 1998 dynamic modelling of melt spinning. The production of fine filaments using the melt spinning process needs considerable effort. The fiber temperature was determined by infrared thermography, and the fiber diameter was determined by highspeed photography.
The homogenized and filtered melt is squirted through narrow channels into a quench chamber where solidification of the fluid filament bundles is achieved fig. A thermoplastic melt is stretched from the spinneret under a constant. It is a specialized form of extrusion that uses a spinneret to form multiple continuous filaments. Simulation of multifilament superfine denier polyester melt. According to ziabicki 20, melt extruding from a spinneret capillary would bulge in all directions. Spinning is a manufacturing process for creating polymer fibers. Science and engineering aspects ziabicki, andrzej, kawai, hiromichi on. Morphology development of polymer blend fibers along. A steadystate model for melt spinning has been used to carry out analytical simulations and subse. Velocity, temperature, stress and diameter profiles of polymers can be obtained via numerical simulation.
We discuss some of the important principles, limitations, and recent developments involved in the formation of filaments through melt spinning. A thermoplastic melt is stretched from the spinneret under a constant takeup speed. A melt spinning apparatus is disclosed for reducing the birefringence variability of melt spun yarn made at high pack throughputs. Pdf the role of flowinduced crystallisation in melt spinning. The neat pet and petposs nanocomposites showed a necklike deformation distinctly from the takeup speed of 3. Mathematical modelling of the pneumatic melt spinning of isotactic.
These measurements were then compared with predictions made with mathematical models for melt spinning and melt blowing. Computer simulation of melt spinning of polyethylene. The effects of prehistory on elongational viscosity and on crystallization were studied by a online measuring method in isothermal melt spinning and in melt spinning. Effects of molecular weight on melt spinning and mechanical. Simulation of multifilament superfine denier polyester. Melt spinning of synthetic polymeric filaments sciencedirect. Online measurement of fiber diameter and temperature in. Suspension dry spinning and rheological behavior of ceramic. A mathematical model of melt spinning was modified for the pneumatic process, taking into account the effects of struc.
A model for the necking phenomenon in highspeed fiber. Identifying breach mechanism during airgap spinning of. In melt spinning, polymer is heated and it melts to form a liquid spinning solution or dope. Karpov institute 42 in the ussr, generated electrospun fibers, which.
A numerical simulation of melt spinning reveals bifurcation of dynamic solutions leading to limited spinning conditions. These works were developed in the following years for different applications 10. Online measurements of fiber temperature and diameter were made for both the meltspinning and the melt blowing processes. Fiber formation influenced by melt spinning dynamics is the main focus of researchers such as ziabicki and kedzierska 1959, 1960, ziabicki 1961, 1976, 1985. Electrospinning is a fiber production method which uses electric force to draw charged threads of polymer solutions or polymer melts up to fiber diameters in the order of some hundred nanometers. Chapter 2 meltspun hollow fibers for use in nonwoven structures. The spinning process requires small melts to flow smoothly down all the c slits. Melt spinning in this process, a polymer is melted and heated to a suitable viscosity for fiber production. The resulting filaments are then subjected to drawing and anealing. The nonwovens formation leszek jarecki in the meltblown process.
673 2 570 294 1324 166 982 1594 627 375 749 616 1738 724 1043 162 207 497 1380 428 167 394 1511 888 530 1539 550 1291 842 1582 618 1632 1128 1348 519 817