Melt Spinning Machine Research Articles

Recycled PET/PA6 Fibers from Waste Textile with Improved Hydrophilicity by In-Situ Reaction-Induced Capacity Enhancement.

Due to the increasing amounts of textile waste, textile to textile recycling is of prime concern. Polyethylene terephthalate (PET) represents the most extensively used type of chemical fiber. Its spinnability suffers from impurities and degradation in the processing, which limits its recycling to new fibers. Here, recycled polyester is blended with a small amount of recycled nylon, and the regenerated fibers, which demonstrated good mechanical properties, were obtained via a melt spinning machine. The mechanical properties, thermal properties, rheological properties, and chemical structure of the modified recycled fibers were investigated. It was found that when compared with rPET-T fibers, the elongation at break of rPET-Ax fibers increased to 17.48%, and the strength at break decreased to 3.79 cN/dtex. The compatibility of PET and PA6 copolymer were enhanced by copolymers produced by in-situ reaction in the processing. Meanwhile, the existence of PA6 increases the crystallization temperature and improves the hydrophilicity of the fibers. This study realized the high-value recycling of waste PET fabric to new fibers, which opens a door for the large utilization of waste textiles.

An investigation on non-flammability properties of polypropylene knitted fabrics

The research performed in recent years regarding synthetic filament yarns is improving the structures and properties of such yarns, and diversifying their usage areas. Most of the current studies being carried out in this field are in the form of bringing functionality to filament yarns. And one of these functional properties is the production of flame-retardant yarns from different types of polymers. In this study, polypropylene (PP) raw material was mixed with organophos- phonate based flame retardancy additive at rates in between 1% and 8% in the feed hopper of a laboratory-type melt spinning machine during PP filament yarn production and then knitted fabric structures were obtained from these yarns. Then the flame retardancy properties of these PP knitted fabrics were tried to be determined by vertical flammability tests and Limit Oxygen Index (LOI) tests. Test results indicated that after flame time and char length values had significantly decreased and values of LOI had increased in knitted fabrics by the increase in additive rate. In conclusion, it was observed that the increase in the rate of flame retardancy additive had significantly improved the non-flammability properties of the PP samples.

Quality Prediction and Abnormal Processing Parameter Identification in Polypropylene Fiber Melt Spinning Using Artificial Intelligence Machine Learning and Deep Learning Algorithms.

Melt spinning machines must be set up according to the process parameters that result in the best end product quality. In this study, artificial intelligence algorithms were employed to create a system that detects abnormal processing parameters and suggests strategies to improve quality. Polypropylene (PP) was selected as the experimental material, and the quality achieved by adjusting the melt spinning machine’s processing parameter settings was used as the basis for judgement. The processing parameters included screw temperature, gear pump temperature, die head temperature, screw speed, gear pump speed, and take-up speed as the six control factors. The four quality characteristics included fineness, breaking strength, elongation at break, and elastic energy modulus. In the first part of our study, we applied fast deep-learning characteristic grid calculations on a 440-item historical data set to train a deep learning neural network and determine methods for multi-quality optimization. In the second part, with the best processing parameters as a benchmark, and given abnormal quality data derived from processing parameter settings deviating from these optimal values, several machine learning and deep learning methods were compared in their ability to find the settings responsible for the abnormal data, which was randomly split into a 210-item training data set and a 210-item verification data set. The random forest method proved to be the best at identifying responsible parameter settings, with accuracy rates of single and double identification classifications together of 100%, for single factor classification of 98.3%, and for double factor classification of 96.0%, thereby confirming that the diagnostic method proposed in this study can effectively predict product abnormality and find the parameter settings responsible for product abnormality.

Fabrication of Recycled Polycarbonate Fibre for Thermal Signature Reduction in Camouflage Textiles.

Thermal signature reduction in camouflage textiles is a vital requirement to protect soldiers from detection by thermal imaging equipment in low-light conditions. Thermal signature reduction can be achieved by decreasing the surface temperature of the subject by using a low thermally conductive material, such as polycarbonate, which contains bisphenol A. Polycarbonate is a hard type of plastic that generally ends up in dumps and landfills. Accordingly, there is a large amount of polycarbonate waste that needs to be managed to reduce its drawbacks to the environment. Polycarbonate waste has great potential to be used as a material for recycled fibre by the melt spinning method. In this research, polycarbonate roofing-sheet waste was extruded using a 2 mm diameter of spinnerette and a 14 mm barrel diameter in a 265 °C temperature process by using a lab-scale melt spinning machine at various plunger and take-up speeds. The fibres were then inserted into 1 × 1 rib-stitch knitted fabric made by Nm 15 polyacrylic commercial yarns, which were manufactured by a flat knitting machine. The results showed that applying recycled polycarbonate fibre as a fibre insertion in polyacrylic knitted fabric reduced the emitted infrared and thermal signature of the fabric.

A Scalable Durable and Seamlessly Integrated Knitted Fabric Strain Sensor for Human Motion Tracking

AbstractTextile strain sensors capable of monitoring human physiological signals and activities have great potential in health monitoring and sports. Integrating them into apparel to be wearable, repeatable, and sensitive remains a great challenge, impeding their practical applications. This paper reports a fabric strain sensor that can be seamlessly integrated into various apparel under precise tension through industrial‐scale production. A conductive core‐sheath polyester/carbon black multifilament (CSPCF) produced on a melt spinning machine is wrapped onto a spandex yarn via a yarn covering machine to manufacture a stretchable double‐covered conductive yarn (DCCY). The fabric strain sensor is specially designed and automatically produced on an industrial knitting machine by precisely integrating the DCCY into an elastic fabric. The sensing principle is contact and separation between neighboring spiral CSPCFs by stretching an arched “rainbow spring” like DCCY embedded in the fabric. The sensor has a high sensitivity of 2% strain detection limit, excellent durability and repeatability for 10 000 cycles, and a wide sensing range of 60% strain, even in a wet state or after repeatedly washing, bending, or rubbing. Three wearable products, by seamlessly integrating the sensor, are demonstrated to effectively and quantitatively detect bending motions of finger, elbow, and knee.

Acoustic and thermal performance of polypropylene nonwoven fabrics for insulation in buildings

Thermal insulation and acoustic absorption materials play a significant role in the characteristics of energy-saving and comfortable modern buildings. However, these two types of materials are generally developed independently. This study highlights the potential of lightweight polypropylene nonwoven fabrics for building applications and investigates how fabric structure affects thermal and acoustical properties. An industrial-scale melt spinning machine was used to produce polypropylene fibers at linear densities of 1.4 and 1.8 dtex. A semi-industrial needle punching line was used to fabricate nonwoven samples with three thicknesses (2, 3, and 4 cm), four porosities (0.83, 0.88, 0.93, and 0.96), and different in- and through-plane fiber orientation distributions. Totally, 31 samples were produced and their sound absorption and thermal insulation performance were assessed using impedance tube and guarded hot plate techniques. Accordingly, the thermal conductivity (Keff) and sound absorption average (SAA) of the samples could be engineered in the range of 0.0270–0.0404 W m-1K-1 and 0.270–0.675, respectively. It was found that fabrics made of finer fibers provide superior acoustic absorption and thermal insulation performance. An increase in through-plane fiber orientation adversely affected the thermal insulation properties, while its effect on acoustic properties depends on the porosity of samples and the sound frequency. The results of statistical analysis showed that in-plane fiber orientation does not have a significant effect on sound absorption behavior, except at frequencies between 4000 and 6300 Hz. It was also found that in-plane fiber orientation does not significantly affect the thermal insulation properties. The best acoustic and thermal performance were achieved by fibrous samples of layered structure made of 1.4 dtex fibers with a thickness of 3 cm (Keff =0.0278 W m-1K-1, SAA = 0.552) and 4 cm (Keff =0.0277 W m-1K-1, SAA = 0.675). The performance of these samples was compared with some commercial products and literature data. The results pointed to the superior acoustic and thermal properties of the designed samples.

Vacuum processing pressure and degradation performance of FePC ribbons in methylene blue solution

The commercial Fe85P5C10 ribbons were refabricated by the melt-spinning machine equipped with vacuum chamber. We controlled the residual pressure after vacuum processing (Pva) in vacuum chamber and investigated the influence of Pva on the microstructure and degradation performance for Methylene Blue (MB) dye. The amorphous formation ability of FePC was enhanced at low vacuuming level and full amorphous ribbons can be obtained at 0.1 and 10 Pa. The amorphous ribbons have a higher degradation efficiency (η) in MB solution than crystalline ribbons, which can be further improved by adjusting the pH to the level pH = 2 and 3. The amorphous ribbons obtained at Pva = 10 Pa has a higher η than that at 0.1 Pa. The surface morphology and chemical state of the reacted surfaces indicate that the higher η of the former is ascribed to its finer 3D nanostructures and stronger galvanic effect of Fe-P/Fe-C bonds.

A STUDY ON ENHANCING THE FLAME RETARDANCY OF POLYPROPYLENE YARN WITH BORON COMPOUNDS

Functional properties such as; water resistance, flame retardancy, antibacterial efficiency etc. are required from textile products. One of the most commonly demanded products among functional textile products is the flame-retardant textiles. In this study, it is aimed to produce polypropylene filament yarn with permanent flame retardancy functionality by adding boron compound, which is Anhydrous disodium tetraborate powder (particle size < 38 micron), to the fiber structure during melt spinning process. In this study two different yarn samples are produced with anhydrous disodium tetraborate content by mass ratios of 2% and 5%. A control polypropylene filament yarn sample is also produced with no additive. By this way, three samples are produced by a conventional BCF polypropylene melt spinning machine with the same production parameters. Then, three knitted fabric samples were produced flat knitting machine. Limiting Oxygen Index (LOI) and vertical flammability tests were applied to the samples. According to results an important level of increase for LOI value is obtained with the sample which has 2% boron compound additive. Nevertheless, there is not a consistent effect of increasing boron content in yarn structure for LOI value. The reason of this situation may be resulted due to the uneven distribution of the boron compound in the yarn structure because of the particle size.

Integration of multivariate control charts and the decision tree classifier to determine the faults of the quality characteristic(s) of a melt spinning machine used in polypropylene fiber manufacturing. Part II: The application of multivariate control charts and the decision tree classifier to determine the faults of quality characteristic(s)

In this study, a multivariate statistical process control was used to analyze the abnormal samples derived from the deviation of optimum processing parameters. The experimental samples derived from the optimum processing parameters were applied as the optimal historical data to determine the control limit, and then the T2 value was obtained from Hotelling's T2 method. If the T2 value exceeds the control limit, the corresponding sample is considered as abnormal. After that, the Runger, Alt and Montgomery method is used to decompose the abnormal T2 value. Then, each quality characteristic value can be obtained and the corresponding decision tree classifier can be implemented. To improve the classification accuracy, we classify the decision tree classifier into single–double identification, single-factor abnormality and double-factor abnormality. For the individual classification test, the result showed that the accuracy of single–double identification was 98.6%, the single-factor abnormality classification was 100% and the double-factor abnormality classification was 96.0%. For the combination classification test, we can get a 98.6% accuracy rate for the single–double identification, 98.3% accuracy rate for the single-factor abnormality classification and 95.3% accuracy rate for the double-factor abnormality classification. Therefore, it can be confirmed that the proposed methods in this study can effectively identify abnormal samples and establish a fault processing parameter diagnosis system for melt spinning machines.

Polyester Yarns Reinforced by Nanoclays

In the present study, poly(ethylene terephthalate)-clay nanocomposite multifilament yarns were prepared using two commercial and four nanoclays synthesized from Resadiye Na-montmorillonite (Na-MMT). Two type multifilament yarns, i.e., fully drawn yarn (FDY) and partially oriented yarn (POY), were melt spun. The FDY yarns were prepared using pilot type Buschaert SpinBoy II CC melt spinning machine with a masterbatch feeding ratio of 4–5% in order to meet industrial machine requirements. The POY spinning was made on the Barmag industrial machine, and the POY yarn was subsequently texturized. All multifilament yarns were prepared via the masterbatch approach, similarly used for the preparation of colored dope dyed yarns. The mechanical properties, flame retardancy, thermal stability, and morphology of produced yarns on melt spinning experiments were analyzed and discussed along with the effect of nanoclay properties such as thermal stability, polymer-clay compatibility, and particle size distribution.

The Performance Promotion of Polyphenylene Sulfide Fibers Based on the Hygroscopic and Dyeable Characteristics

The hygroscopic and dyeable polyphenylene sulfide (PPS) composite fiber was prepared using a twin-screw extruder and a melt spinning machine. A new dyeing process was proposed and the moisture absorption and dyeing mechanism of the composite fiber was analyzed. The results show that sodium polyacrylate (PAAS) is uniformly dispersed in the PPS matrix and is compatible with PPS at the macromolecular level. The thermal properties of the composite fibers are basically unchanged, and the crystallinity is slightly reduced. With the increase of PAAS content, the normal moisture regain of the composite fiber reached 2.11 % from 0.21 %, and the contact angle decreased from 73.8 ° to 52.3 °. Under the new dyeing technology, the dyeing rate of the composite fiber reached 93 %, and the washing fastness was grade 5. The mechanism of hygroscopicity and dyeing of macromolecular space networks and polyelectrolyte was proposed.

Development of N-halamine Low-Melting Point Poly(ethylene terephthalate) Fibers via Melt Spinning: Structural Characterization and Demonstration of Rechargeable Antibacterial Properties

ABSTRACT Antibacterial low-melting-point poly(ethylene terephthalate) (LMP-PET) fibers are produced via melt spinning. First, LMP-PET granules are modified by free radical graft polymerization of acrylamide (AAm), an N-halamine precursor, using a twin-screw extruder to conduct reactive melt extrusion. The modified granules are spun into fibers using a melt spinning machine. The fibers are characterized by various analytical techniques. Potent rechargeable antibacterial properties of the fibers are assessed and demonstrated by zone of inhibition test, counting bacterial colonies, and imaging of dead bacteria. It is shown that increasing AAm concentration yields to enhanced rechargeable antibacterial properties while fibers structural properties are preserved.

Integration of multivariate control charts and decision tree classifier to determine the faults of the quality characteristic(s) of a melt spinning machine used in polypropylene as-spun fiber manufacturing Part I: The application of the Taguchi method and principal component analysis in the processing parameter optimization of the melt spinning process

Melt spinning is the most extensively used method of fabricating polymeric fibers in the textile industry. This series of studies aimed to construct an automatic abnormality diagnosis system for polypropylene (PP) as-spun fiber produced by the melt spinning process. Part I of this study aimed to construct the processing parameter optimization for the PP as-spun fiber produced by the melt spinning machine. The product quality resulting from the processing parameters of the melt spinning process included six control factors: extruder temperature, gear pump temperature, die-head temperature, rotational speed of extruder, rotational speed of gear pump, and take-up speed. The quality characteristics included fiber fineness, breaking strength, breaking elongation, and modulus of resilience. The quality data were derived from the experiments, the design of which were based on the orthogonal array of the Taguchi method in order to calculate the signal-to-noise ratio, analysis of variance, and confidence interval. Principal component analysis was then applied to eliminate the multi-correlation of the output responses and transform the correlated responses into principal components, to obtain multi-quality optimum processing parameters. These optimum parameters, including the extruder temperature (180°C), gear pump temperature (220°C), die-head temperature (240°C), the rotational speed of the extruder (7.5 rpm), the rotational speed of the gear pump (15 rpm), and take-up speed (700 rpm) would later be used to build a prediction of an abnormality diagnosis system for identification of fault processing parameters in a melt spinning machine in Part II of this study.

Corrosion Resistance of Mg72Zn24Ca4 and Zn87Mg9Ca4 Alloys for Application in Medicine.

The aim of this work was to monitor the corrosion rate of the Mg72Zn24Ca4 and Zn87Mg9Ca4 alloys. The purity of the alloying elements was 99.9%. The melt process was carried out in an induction furnace. The melting process took place under the cover of an inert gas (argon). The copper form was flooded by liquid alloy. Then, in order to obtain ribbons, the cast alloy, in rod shape, was re-melted on the melt spinning machine. The corrosion resistance of both alloys has been determined on the basis of the following experiments: measurements of the evolution of OCP (open circuit potential), LSV (linear sweep voltamperometry) and EIS (electrochemical impedance spectroscopy). All corrosion tests were carried out in Ringer’s solution at 37 °C and pH 7.2. The corrosion tests have revealed that the zinc alloy, Zn87Mg9Ca4, exhibits significantly higher corrosion resistance in the Ringer solution compared to the magnesium alloy, Mg72Zn24Ca4. Moreover, it has been shown that the cathodic reaction proceeds faster on the surface of ribbons. EIS measurements show that the dissolution of Mg alloy proceeds with two steps: transfer of Mg2+ ions to the Ringer solution and then the formation of the corrosion products, which are deposited on the surface of magnesium alloy. It has been revealed, too, that for both bulk materials, diffusion of chloride ions through the corrosion product’s layer takes place.

Poly(ethylene terephthalate)–Clay Nanocomposite Multifilament Yarn: Physical and Thermal Properties

Poly(ethylene terephthalate)/clay nanocomposite multifilament yarn was manufactured by conventional masterbatch approach. Poly(butylene terephthalate) was used as a carrier polymer in masterbatch steps. The masterbatches were diluted into pilot melt spinning machine and subsequently drawn with 2.65 ratios to prepare fully oriented yarn. The degree of dispersion in nanocomposite fibers was analyzed by X-ray diffractometry and scanning electron microscopy. Even though the addition of nanoclay reduced mechanical properties of nanocomposite fibers, dimensional stability could be improved at certain clay contents. The flammability properties were sufficiently improved, and no significant changes were observed with increasing clay content. The main novelty of this paper is the development of a proper approach for the selection of optimum carrier polymer for nanoclay in masterbatch preparation, as well as proper nanoclay for desired polymers. The acid-base approach is used in evaluating the surface free energy of commercial nanoclay and calculation the total interaction energies between polymer and clay surfaces. Such an approach gives adequate information about polymer-clay compatibility and provides a useful tool in the selection of optimum carrier polymer, as well as proper nanoclay for the desired polymer during masterbatch preparations.

Improved Thermal Processing of Polylactic Acid/Oxidized Starch Composites and Flame-Retardant Behavior of Intumescent Non-Wovens

Thermoplastic processing and spinning of native starch is very challenging due to (a) the linear and branched polymers (amylose and amylopectin) present in its structure and (b) the presence of inter-and-intramolecular hydrogen bond linkages in its macromolecules that restrict the molecular chain mobility. Therefore, in this study, oxidized starch (OS) (obtained after oxidation of native starch with sodium perborate) was melt-blended with polylactic acid (PLA) polymer to prepare PLA/OS blends that were then mixed together with ammonium polyphosphate (APP), a halogen-free flame retardant (FR) used as acid donor in intumescent formulations on twin-screw extruder to prepare PLA/OS/APP composites. OS with different concentrations also served as bio-based carbonic source in intumescent formulations. PLA/OS/APP composites were melt spun to multifilament fibers on pilot scale melt-spinning machine and their crystallinity and mechanical properties were optimized by varying spinning parameters. The crystallinity of the fibers was studied by differential scanning calorimetry and thermal stabilities were analyzed by thermogravimetric analysis. Scanning electron microscopy was used to investigate the surface morphology and dispersion of the additives in the fibers. Needle-punched non-woven fabrics from as prepared melt-spun PLA/OS/APP fibers were developed and their fire properties such as heat release rate, total heat release, time to ignition, residual mass % etc. by cone calorimetry test were measured. It was found that PLA/OS/APP composites can be melt spun to multifilament fibers and non-woven flame-retardant fabrics produced thereof can be used in industrial FR applications.

Novel Bicomponent Functional Fibers with Sheath/Core Configuration Containing Intumescent Flame-Retardants for Textile Applications.

The objective of this study is to examine the effect of intumescent flame-retardants (IFR’s) on the spinnability of sheath/core bicomponent melt-spun fibers, produced from Polylactic acid (PLA) single polymer composites, as IFR’s have not been tested in bicomponent fibers so far. Highly crystalline PLA-containing IFR’s was used in the core component, while an amorphous PLA was tested in the sheath component of melt-spun bicomponent fibers. Ammonium polyphosphate and lignin powder were used as acid, and carbon source, respectively, together with PES as a plasticizing agent in the core component of bicomponent fibers. Multifilament fibers, with sheath/core configurations, were produced on a pilot-scale melt spinning machine, and the changes in fibers mechanical properties and crystallinity were recorded in response to varying process parameters. The crystallinity of the bicomponent fibers was studied by differential scanning calorimetry and thermal stabilities were analyzed by thermogravimetric analysis. Thermally bonded, non-woven fabric samples, from as prepared bicomponent fibers, were produced and their fire properties, such as limiting oxygen index and cone calorimetry values were measured. However, the ignitability of fabric samples was tested by a single-flame source test. Cone calorimetry showed a 46% decline in the heat release rate of nonwovens, produced from FR PLA bicomponent fibers, compared to pure PLA nonwovens. This indicated the development of an intumescent char by leaving a residual mass of 34% relative to the initial mass of the sample. It was found that the IFRs can be melt spun into bicomponent fibers by sheath/core configuration, and the enhanced functionality in the fibers can be achieved with suitable mechanical properties.

Temperature Regulation in Colored Infrared-Transparent Polyethylene Textiles

Summary Effectively regulating heat flow between the human body and its environment not only increases thermal comfort but also presents a novel and potentially cost-effective approach to reducing building energy consumption. Infrared property-engineered textiles have been shown to passively regulate radiative heat dissipation for effective cooling and warming of the human body. However, a lack of dyes that can tune the textile color without compromising the infrared properties remains a major impediment to textile commercialization. Here, we report a new strategy utilizing inorganic nanoparticles as a coloring component for scalable brightly colored, infrared-transparent textiles. The as-fabricated composite textiles not only show a high infrared transparency of ∼80% and a passive cooling effect of ∼1.6°C–1.8°C but also exhibit intense visible colors with good stability against washing. This facile coloration approach will promote the commercialization of radiative cooling textiles in temperature-regulating wearable applications for effective energy savings.

Recycled fiber from straw waste: effect of take-up speed and spinneret diameter to linear density and tenacity

Recycled fiber has a great potential as a solution to meet overgrowing synthetic fiber demand and reduce plastic waste in the same time. In the previous research, bottle cap waste is used as the material of the recycled fiber. The result shows that fiber tenacity of recyled fiber from bottle cap waste has low tenacity, different polymer. This phenomena may have been caused by the present of pigment molecule. This research focused on producing recycled fiber from straw waste which has low pigment content. Straw waste was washed and cleaned before the cutting process. Then, the waste was processed in the experiment melt spinning machine with plunger system and single hole orifice in various diameter, 4 mm, 10 mm and 15 mm. The processing temperature was 140° C temperature in three take-up speed, 3.00 m/minutes, 10.30 m/ minutes and 19.16 m/ minutes. The diameter and cross section shape of recycled polyethylene fiber were obtained by using electric microscope with software assistance. The linear density of the recycled fiber was analysed by calculating it with denier and the mechanical strength of the fiber was measured in accordance with the ASTM D 3379-75 standard. High take-up speed leads to higher linear density and take-up speed value is proportionally linear with the tenacity of fiber produced. Moreover, the spinneret diameter is proportionally linear with linear density but it is inversely linear with the tenacity of the fiber produced.

Fiber-on-fiber friction measurement using hanging fiber method

Estimation and evaluation of frictional behavior of delicate materials such as textile fibers is contingent upon existence of accurate experimental methods. In this work, the effect of fiber fineness on frictional behavior of polypropylene fibers was investigated using a developed high-precision experimental setup based on hanging fiber method. Fiber fineness was varied by varying the spinning pump speed during production of melt-spun fibers on an industrial scale melt spinning machine. Data acquisition was achieved using Delphi programming software. A geometrical model capable of evaluating the frictional force between two in-contact identical fibers was proposed. Fiber-on-fiber frictional force was expressed by a third degree polynomial function of fiber diameter. The least value of frictional force was found to belong to fiber diameter of 49.1 μm which corresponds to linear density of 15.5 den. It was concluded that frictional behavior of fibers is influenced by factors such as contact point geometry, rate of fiber strain and profile of generated heat.