Filament Material Research Articles

Reinforcement‐material effects on the compression behavior of polymer composites

AbstractAdditive manufacturing technique fused filament fabrication (FFF) has found widespread usage in a variety of sectors, because of its ability to produce parts with arbitrary geometries and intricate internal structures. This study focuses on the characterization of polylactic acid (PLA) and polyethylene terephthalate glycol (PETG) composites under compressive force to learn more about how various nozzle diameter (ND) and infill pattern (IP) affect the fabricated specimens. The specimens are created with various combination of IPs (triangular, honeycomb, and rectilinear) and NDs (0.2, 0.4, and 0.6 mm) utilizing three polymer composites namely carbon fiber filled PLA (CF‐PLA), carbon fiber filled PETG (CF‐PETG), and multi walled carbon nano tubes filled PLA (MWCNTs‐PLA). According to the findings, the higher ND improves the compressive properties of the polymer composites. The IP also has significant impact on the compressive properties of the fabricated specimens. The overall minimum compressive strength of 14.612 MPa at ND 0.2 mm and honeycomb IP for CF‐PLA specimen. The overall maximum compressive strength achieved is 45.269 MPa at ND 0.6 mm and rectilinear IP for MWCNTs‐PLA specimen. Therefore, the compressive strength is enhanced by 209.81% by modifying the process parameters and filament material. Based on statistical analysis using Taguchi method, the ND contributes highest, 79.61% to compressive strength of MWCNTs‐PLA specimens, but for CF‐PLA and CF‐PETG specimens, IP contributes highest, 52.65% and 57.91%, respectively. The aforementioned findings will be extremely useful to scientists attempting to achieve sustainability through the use of polymer composites and FFF process.

Interactions between Filament Fibrils and a Network Field

Filaments are common structures in the solar atmosphere, and usually interact with their surrounding magnetic fields. However, interactions between filaments and network fields are rare. Here, we report interactions between filament fibrils and a nearby network field in the quiet Sun by employing observations from the New Vacuum Solar Telescope (NVST) and Solar Dynamics Observatory. NVST Hα images show that several filament fibrils separated from the main body of the filament, and moved sideward. While a fibril met the network field, the movement of the fibril segment corresponding to the network field slowed down. Subsequently, weak extremely ultraviolet brightenings appeared near the interface of the filament and the network field, and then the fibril materials began to converge toward the network field. Meanwhile, continuous redshift signal enhancements appeared in the corresponding Dopplergrams, accompanying the convergences of the fibril materials. About 10 and 35 minutes later, two other similar processes occurred again. These observations imply that the network field blocks movements of the filament fibrils and weak magnetic reconnections between the blocked fibrils and the network field take place. We suggest that new field lines developed due to the magnetic reconnections, along which fibril materials fell down into the lower solar atmosphere. These results provide a new picture of filament material drainage.

Extrusion strategies in fused deposition additive manufacturing: A review

Fused deposition or fused layer additive manufacturing is a technique in which a part is fabricated layer by layer using filament or pellets-form input material. The extruder is the central part of the fused deposition additive manufacturing (FDAM) system. The extrusion mechanism is unique to the geometry and form of the feedstock material. Extrusion of filament-form material through the nozzle needs to design of a material feeding mechanism based on various filament extrusion parameters. At the same time if the material is in the form of pellets, then the design of the feeding mechanism is very different due to the shape and size of the pellets. These two different design strategies for material extrusion namely the design of the feeding mechanism of filament and pellets form materials have been a major concern to avoid unwanted deformation of extruded materials in FDAM. These two design strategies for filament and pellet-form materials have led to the development of several material extrusion strategies. The present paper reviews various material extrusion strategies developed for FDAM of filament or pellets form input material. This article presents the review of design, development, performance evaluation, and process planning for each extrusion strategy. Based on the literature review authors have suggested a possible extrusion method that can accept both forms of materials to fulfill the need for the filament as well as pellets-based additive manufacturing.

FDM YÖNTEMİYLE ÜRETİLEN ABS, PLA VE PETG NUMUNELERİN YÜZEY PÜRÜZLÜLÜĞÜ VE ÇEKME DAYANIMININ MODELLENMESİ VE OPTİMİZASYONU

Bu çalışma, Eriyik Yığma Modelleme (FDM) teknolojisi kullanılarak üretilen numunelerin yüzey kalitesi ve çekme dayanımı üzerinde ABS, PLA ve PETG filamentlerin ve baskı parametrelerinin etkisini incelemektedir. Bu amaçla, Taguchi L27 dizinine göre baskı deney tasarımı yapılmıştır. Filament malzemesi, dolum oranı, katman kalınlığı, doldurma hızı ve tarama açısı baskı parametreleri iken, yüzey pürüzlülüğü ve çekme mukavemeti de baskı kalitesi göstergeleridir. Ayrıca, deneysel ölçümler sonucu elde edilen yüzey pürüzlülüğü ve çekme dayanımı değerlerini matematiksel olarak modellemek için regresyon analizi de uygulanmıştır. Bu çalışmanın sonuçları filament malzemesinin yüzey pürüzlülüğü ve çekme dayanımı üzerinde önemli bir rol oynadığını göstermektedir. ABS ve PETG filamentlere göre PLA filament de yüzey pürüzlülüğünün sırasıyla ortalama %7,23ve %54,19 oranında daha az olduğu ve ayrıca, diğer filamentlere göre PLA filament de çekme dayanımın sırasıyla ortalama %46,46 ve %34,12 oranında daha yüksek olduğu tespit edilmiştir.

FFF 방식 적층성형의 층 성형시간이 형상 오차에 주는 영향

Additive manufacturing technology is widely being used for the prototype of parts or products by ease and low cost compared to casting and subtractive manufacturing. Especially FFF (Fused Filament Fabrication) method is mainly used not only for industrial prototype but also emerging in commercial products for comparably low costs and difficulties in post processing. But dimensional accuracy of FFF method is lower than other additive manufacturing methods since laminating of layer is processed at high temperature. To increase the dimensional accuracy of FFF method, studies were carried out about factors causing dimensional errors on parts (layer height, infill percentage, heating bed temperature etc.). In this study, the dimensional accuracy of parts made by additive manufacturing with the FFF method is investigated. The main goal of this study is to check whether the varying printing time of each layer affects the dimensional accuracy of parts when multiple parts are printed at once. Models having identical planar shapes but various heights are printed and investigated. The ABS was used as the filament material for the additive manufacturing.

Optimasi Parameter 3D Printing Menggunakan Material PP Daur Ulang pada Spesimen ASTM 638 D 10 type 1 dengan Response Surface Method

Recycling plastic waste is one way to minimize the negative impact on the environment. The use of additive manufacturing which speeds up the prototyping process and product design currently uses a 3D printer with ABS and PLA filament materials. Remaining filaments and unused parts/prototypes, or products that have been manufactured with actual materials will be discarded. This causes waste for the environment. The use of recycled filament for 3d printing machines is one way to deal with plastic waste, besides that the use of recycled filament is a way to reduce the cost of plastic filament. Recycled plastic filament is used for 3d printer machines with the Fused Deposition Modeling (FDM) type. In this method the plastic filament material is melted and then extruded according to the desired pattern. In this study the results of the prints were tested using the tensile test method. Parameters used, print temperature, layer height, print speed. Response data analysis uses the Response Surface Method (RSM) with the Box-Behnken type. The results of the tensile test data were analyzed using Analysis of Variance (ANOVA). Based on the results of the ASTM D638-10 type 1 tensile test analysis, the print temperature parameter is 2600C, the layer height is 0.12 mm and the maximum print speed is 50 mm/s.

Steam-sterilized and degradable fused filament fabrication-printed polylactide/polyhydroxyalkanoate surgical guides for dental implants: Are they accurate enough for static navigation?

Three-dimensional (3D) printing is a rapidly evolving field and has gained increasing importance in the medical sector. However, the increasing usage of printing materials is accompanied by more wastages. With a rising awareness of the environmental impact of the medical sector, the development of highly accurate and biodegradable materials is of great interest. This study aims to compare the accuracy of polylactide/polyhydroxyalkanoate (PLA/PHA) surgical guides printed by fused filament fabrication and material jetted guides of MED610 in fully guided dental implant placement before and after steam sterilization. Five guides were tested in this study and each was either printed with PLA/PHA or MED610 and either steam-sterilized or not. After implant insertion in a 3D-printed upper jaw model, the divergence between planned and achieved implant position was calculated by digital superimposition. Angular deviation and 3D deviation at the base and the apex were determined. Non-sterilized PLA/PHA guides showed an angle deviation of 0.38 ± 0.53° compared to 2.88 ± 0.75° in sterile guides (P > 0.001), an offset of 0.49 ± 0.21 mm and 0.94 ± 0.23 mm (P < 0.05), and an offset at the apex of 0.50 ± 0.23 mm before and 1.04 ± 0.19 mm after steam sterilization (P < 0.025). No statistically significant difference could be shown for angle deviation or 3D offset at both locations for guides printed with MED610. PLA/PHA printing material showed significant deviations in angle and 3D accuracy after sterilization. However, the reached accuracy level is comparable to levels reached with materials already used in clinical routine and therefore, PLA/PHA surgical guide is a convenient and green alternative.

Mechanical Characterization of Filler Modified ABS 3D Printed Composites Made via Fused Filament Fabrication

Rapid prototyping (also known as additive manufacturing, AM) is a quickly developing process with increasing new applications in a large variety of industrial sectors (i.e., aerospace, automotive, medical, among others.) However, despite the great advantage of a decoupled price to part complexity of an AM fabricated structure, the material properties (largely governed by filament material and printing parameters) still present a significant limiting factor. In this context, the development of new filament materials for a wider range of applications has great potential. In this study, the influence of micro-scale filler reinforcement (powders), both natural (curauá) and synthetic (glass fibre), in the fabrication of an Acrylonitrile Butadiene Styrene (ABS) filament was evaluated. The filler was controlled by weight fraction (~1%) and the filament was fabricated via extrusion. A commercially available 3D printer was used to print tensile and flexural specimens for mechanical characterization as per ASTM standards. The fracture morphology was analysed after tensile testing via optical microscopy in order to evaluate the effect of the fillers on the material deposition and void formation. No significant variation in the tensile properties was reported, except for the strain at failure, while more significant flexural strength variation was observed as a function of filler material. The fillers presented a significant effect on the void density of the fractured surface. It was demonstrated that this simple fabrication technique can generate novel filament materials that may enhance the mechanical properties or widen the range of application (e.g., faster decomposition times in nature for single-use plastics due to the hydrophilic nature of the natural filler and lower water absorption of the hydrophobic synthetic filler for marine environment applications).

Parametric Investigation of FDM Process Parameter on Impact Strength of 3D-Printed Part

Abstract: The method of producing three-dimensional solid items from digital data is known as additive manufacturing (AM), sometimes known as 3-D printing. A rapidly expanding additive manufacturing technique with several applications is fused deposition modeling (FDM). In this study, we investigate how the orientation, infill pattern, and density of the infill affect the impact strength of the ASTM D-256 specimens. A 3- printer with Acrylonitrile Butadiene Styrene (ABS) filament material has been used in this study. To evaluate the impact strength of the printed object and represent their quality, an ASTM D256 specimen standard has been used. The various parameters for the experiment were selected using OVAT analysis. With the help of a design of experiments (DOE) using Taguchi's L9 Array along with infill pattern, orientation, and density, the operational dependence is examined. When analysis of variance (ANOVA) is used to identify the relevant 3D printing process parameter it is shows that orientation and infill pattern are most significant parameters for impact strength.

Investigation of Fused Deposition Modelling Process Parameters in 3D Printing for Composite Material (Poly Lactic Acid and Banana Fibre)

Additive manufacturing is gaining popularity nowadays due to its applications in the automotive, medical, aerospace industries, and sports to manufacture complex parts. Fused deposition modelling is an additive manufacturing process utilised widely due to its lower cost, fast prototyping and faster production time. The present study focuses on applying FDM to the composite material filament and the impact of parameters of FDM on the part quality. A composite filament material was prepared to combine PLA (Poly-lactic Acid) and banana fibre. Specimens were prepared using this composite filament by varying various parameters such as layer thickness, infiltration and build orientation. Flexural and tensile tests were performed as per standards. It was found that the material properties considered are significantly affected by percentage infill and build orientation. The ‘on edge’ build orientation provides better material properties as compared to the other two orientations. The tensile strength is observed to be 73% and 77% more in flat orientation and ‘on edge’ orientation, respectively, as compared to upright orientation. Also, the flat orientation and ‘on edge’ orientation respectively showed 60% and 70% more flexural strength than the upright orientation.

Mechanical Properties of 3D-Printed Components Using Fused Deposition Modeling: Optimization Using the Desirability Approach and Machine Learning Regressor

The fused deposition modelling (FDM) technique involves the deposition of a fused layer of material according to the geometry designed in the software. Several parameters affect the quality of parts produced by FDM. This paper investigates the effect of FDM printing process parameters on tensile strength, impact strength, and flexural strength. The effects of process parameters such as printing speed, layer thickness, extrusion temperature, and infill percentage are studied. Polyactic acid (PLA) was used as a filament material for printing test specimens. The experimental layout is designed according to response surface methodology (RSM) and responses are collected. Specimens are prepared for testing of these parameters as per ASTM standards. A mathematical model for each of the responses is developed based on the nonlinear regression method. The desirability approach, nonlinear regression, as well as experimental values are in close agreement with each other. The desirability approach predicted the tensile strength, impact strength, and flexural strength with a less percentage error of 3.109, 6.532, and 3.712, respectively. The nonlinear regression approach predicted the tensile strength, impact strength, and flexural strength with a less percentage error of 2.977, 6.532, and 3.474, respectively. The desirability concept and nonlinear regression approach resulted in the best mechanical property of the FDM-printed part.

Short basalt fibre reinforced recycled polypropylene filaments for 3D printing

Additive Manufacturing (3D Printing, and specifically Material Extrusion) is a rapid and convenient manufacturing method using raw material in filament form and is a potential candidate process for the use of recycled plastics and fibres gathered from industrial waste and domestic recycling. In this research, off-cuts of basalt fibre and recycled mushroom trays made of Polypropylene (PP) have been collected, recycled and combined in an extruder to make short fibre reinforced filaments as material extrusion feedstock filament material. A Noztek Touch Dual PID filament maker was utilized to make reinforced PP with 0%, 2%, 5%, and 8% basalt fibre weight fractions. The extruding parameters including motor speed, heating temperatures, cooling fan status, extrusion tension have been optimized to produce a filament made from these waste materials with the desired surface quality, void content, and profile. Microscopic assessment has been carried out to verify the fibre dispersion and above mentioned quality measures in the upcycled filaments. Differential scanning calorimetry has been done to measure the melting and crystallization temperatures of collected polypropylene and recycled filaments, and the tensile strength and elastic modulus of the reinforced recycled polypropylene have been measured in presence of different percentages of short basalt fibres with 4.5 mm length. The produced filaments with 5% wt. of basalt are a good candidate for use as feedstock in manufacturing using 3D printing.

Production of compression and flexural test samples in 3D printer with PLA polymeric biomaterial and bone compression with appropriate properties

In this study, it is planned to design and develop a structure close to the real bone strength properties by using PLA (polylactic acid) material. 3D printers have started to take place in our daily lives with today's developing technology and are preferred because of their ease of production and low cost. It has been determined that the PLA biomaterial can be used as a bone substitute in the body. The samples produced have different filling ratios and different internal structures. In the study, the effects of changes in the internal structure on the mechanical properties were investigated. Bone geometry is considered as an important factor among the parameters affecting biomechanical properties. In order to determine the mechanical properties of PLA filament material, bending and compression samples were prepared as 3 pieces for each test. The aim of this study is to determine whether it can be used as bone in the body by measuring the mechanical properties of biocompatible PLA polymer material. In the current work, the quality of the 3d printer and the material used in production directly affects the mechanical properties. In bones in the human body, trabecular bone has 80% porosity and cortical bone 10% infill. In this study, it was tried to obtain structures with properties close to real bone strength by using test specimens with different infill rates. It has been determined from the obtained data that PLA polymer material can be developed and meet the mechanical values in bone.

Effects of Printing Parameters on Properties of FDM 3D Printed Residue of Astragalus/Polylactic Acid Biomass Composites.

In order to develop a new kind of filament material for the fused deposition modeling (FDM) 3D printing, the residue of Astragalus (ROA), one of the most important Chinese herbal medicines, and polylactic acid were chosen as the raw materials to FDM 3D print biomass composite specimens, the effects of the printing parameters on the properties of the specimens were investigated. The results indicated that the mechanical properties and thermal stability of the printed specimen were affected obviously by the parameters while the melting and crystallization behavior of the specimens were little affected. For the wettability, it was also little affected by the printing parameter except for the printing speed. Increasing the printing temperature and the filling density or reducing the printing speed and the layer thickness could improve both the mechanical properties and the thermal stability of the FDM 3D printed PLA/ROA composite specimen; reducing the deposition angle could also improve the mechanical properties while having little effect on the thermal stability of the specimen.

Double-ridged waveguide for efficiently heating ultrafine filament fibers

Microwave heating has attracted wide attention in fiber dyeing, refining, drying and modification due to its energy saving and environmental protection. However, effectively heating ultrafine filament fibers is difficult to achieve using conventional microwave heating devices because of their low power density and rapid heat dissipation at their surfaces. Thus, we designed a double-ridged waveguide operating at 2.45 GHz, facilitating rapid heating of ultrafine structure by increasing the electric field strength, subsequently causing higher power absorption by the ultrafine materials. First, the proposed waveguide was compared with other types of cavities by building a multiphysics model, incorporating electromagnetics and heat conduction of the heated filament fiber with a relative permittivity of 5.7–0.2j and a diameter of 0.008 times of the wavelength of vacuum. The electric field strength and power absorbed of the filament fiber located in the proposed ridged waveguide were approximately 13.3 and 180 times higher than that in WR430, a commonly used rectangular waveguide in system designs. Additionally, we built an experimental system to demonstrate that the design can efficiently heat a single filament fiber at low input power of 70 W. Furthermore, the effects of the filament fiber size, material permittivity, and cavity temperature on heating were investigated based on the constructed model.

Redesign of a Metallic Component Using Polylactic Acid – PLA by Fused Deposition Modeling – FDM for Durability Increase

AbstractThe term “3D printing” can refer to a variety of processes where material is deposited, joined, or solidified under computer control to create a three‐dimensional (3D) object. According to this principle, the material is added (such as fluid molecules or powder grains being fused together), typically layer by layer. One of the key advantages of 3D printing is the ability to produce very complex shapes or geometries, from the simplest to the most complex, that will be otherwise impossible to construct by hand, including hollow parts or parts with internal truss structures to reduce weight. In industries and companies where 3D printing is still a relatively new addition, the polylactic acid (PLA) material is the best option, because it is known in the industry as the easiest filament material to print. It is ideal for those who are looking to carry out fast prototyping, therefore it is the perfect choice for quick work. In this article, the authors intend to establish a set of printing rules for a geometric shape made of polymeric material (PLA) through the 3D printing process for a practical application and to present as much as possible the behavior in time of this printed component that replaces a non‐corrosive metal component.

Characterization of Tissue Equivalent Materials Using 3D Printing for Patient-Specific DQA in Radiation Therapy

Three-dimensional printing technology has the advantage of facilitating the construction of complex three-dimensional shapes. For this reason, it is widely used in medical and radiological fields. However, few materials with high electron density similar to that of bone exist for fabricating a human phantom. In this study, commercially available filament materials were used with an FDM 3D printer to perform delivery quality assurance (DQA) and were evaluated for medical use. For the bone filament material, BaSO4 was synthesized in five ratios of 2%, 4%, 6%, 8%, and 10% with 40% PBAT and 50~58% PLA. The electron density for the 3D printing material fabricated was obtained using kV energy CT and compared with the electron density of human organs and bones. The radiation beam properties of the 3D printed structures were analyzed as films for treatment using a linear accelerator. As a result, by changing the infill density of the material, it was possible to produce a material similar to the density of human organs, and a homogeneous bone material with HU values ranging from 371 ± 9 to 1013 ± 28 was produced. The 3D printing material developed in this study is expected to be usefully applied to the development of a patient-specific phantom to evaluate the accuracy of radiotherapy.

Investigation of Mechanical Properties of FDM-Processed Acacia concinna–Filled Polylactic Acid Filament

In this work, an Acacia concinna filler was blended in a polylactic acid matrix using a single-screw extruder. A composite filament material made from an extruder was used to fabricate polylactic acid/25 wt% A. concinna (PLA/25 wt% AC) composites via a fused deposition modeling (FDM) technique. Composites were fabricated by varying layer thickness, infill density, and printing speed based on Taguchi L9 experimental design. Tensile, flexural, and impact tests were conducted on the printed composite samples as per the ASTM standards. The significance of factors impacting the mechanical properties was determined using analysis of variance. To estimate the strength of PLA/AC composites, mathematical models were developed. In addition, the fractured specimen was examined using scanning electron microscopy to determine the mechanism of fracture. Both the layer height and the infill percentage exhibited a positive influence on strength, which suggests that the layer height or the infill percentage, or both, will increase the material’s strength. The printing speed had a negative influence on the strength, which indicates that the strength decreases as the printing speed increases. The findings suggested that PLA/AC composites could be used to fabricate high-strength, lightweight components using FDM.

A Review on Tribological Behaviour of 3D Printed Mechanical Components

Abstract Technologies such additive manufacturing are slowly becoming more and more present on the market, covering different areas of the industry due to its great potential. Even so, there are still many aspects which are unexplored or which can be improved. One of them being the study of the tribological proprieties for all these parts, which are produced through additive manufacturing methods, such as powder bed fusion, binder jetting, direct energy deposition, fused filament fabrication, material jetting, vat photopolymerization, and sheet lamination. The scope of this paper is to bring together the tribological proprieties for the 3D printed parts, and to have a critical analysis of these proprieties, in order to easily decide which printing method is suitable, depending of the working conditions of the printed component. In addition, this paper will describe the working principle for each technology, and the type of materials that are commonly used in the printing process. Depending of the printing method, the tribological proprieties vary greatly. For example, for the parts which are manufactured through powder bed fusion, it was found that the wear resistance is higher, and with a lower friction coefficient than for a part manufactured through traditional methods. In addition, for many printing methods, the produced part might require an additional step of treatment. This is the case with binder jetting, where infiltration and sintering are often used because the 3D-printed part is porous and weak. Some researchers found that the average friction coefficient measured for a steel-based part, treated with bronze infiltration, is comparable with the friction coefficient measured on a part made of the same material, manufactured through the direct energy deposition method. Of course, due to the physical limitations of the 3D printing method, the system will allow only the usage of a specific type or class of materials. One of such method is fused filament fabrication, where only thermoplastics are used. Along with vat photopolymerization and material jetting, these methods present comparable tribological proprieties.

The Effects of CaCl2 and Cellulose Concentrations on the Cellulose/PVA/Alginate-Based Filaments Production by Wet Spinning

Cellulose as an abundantly available natural polymer can be utilized as an environmentally friendly filament material through combination with polyvinyl alcohol (PVA) and alginate. The study on cellulose/PVA/alginate composite as filament material haven not been widely reported and the effects of parameter process on the resulting filament properties still have room to be explored further. Therefore, this study focused on the effect of CaCl2 and cellulose concentration on the cellulose/PVA/alginate filaments’ thermal and mechanical properties. In this study, isolated cellulose from Oil Palm Empty Fruit Bunches (OPEFBs) was used as a reinforcement agent in filament production with PVA and alginate as a matrix by wet spinning in a CaCl2 solution as the coagulant solvent. The prepared dopes of cellulose/PVA/alginate at 5, 10 and 15 % cellulose concentration were spun using a syringe pump into 5 and 13 % CaCl2 ­coagulation bath. Subsequently, the resulting filaments’ mechanical and thermal properties were tested. The crystallinity and thermal stability of the filaments coagulated in 13 % CaCl2 were higher than those of in 5 % CaCl2. However, the tensile strength of the filament produced showed just the opposite. Cellulose concentration increase resulted in filament with improved thermal stability and tensile strength, and higher crystallinity. Concisely, higher CaCl2 and cellulose concentration enhanced the filament thermal properties but higher CaCl2 concentration led to filament mechanical property depression contrast to cellulose which higher concentration led to mechanical property increase. Filament has potential application in 3D printing for various application, especially filament with biodegradable, biocompatible, and enhanced mechanical property is potential for particular application such as biomedical applications as a surgical thread or biodegradable scaffold.&#x0D; HIGHLIGHTS&#x0D; &#x0D; Cellulose as an abundantly available natural polymer can be utilized as an environmentally friendly filament material through combination with polyvinyl alcohol (PVA) and alginate&#x0D; Isolated cellulose from Oil Palm Empty Fruit Bunches (OPEFBs) was used as a reinforcement agent in filament production with PVA and alginate as a matrix by wet spinning in a CaCl2 solution as the coagulant solvent&#x0D; Cellulose concentration increase resulted in filament with improved thermal stability and tensile strength, and higher crystallinity&#x0D; &#x0D; GRAPHICAL ABSTRACT