THE EFFECT OF SUPPORTING MATERIAL TYPE ON THE NANOFIBER MORPHOLOGY

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1 THE EFFECT OF SUPPORTING MATERIAL TYPE ON THE NANOFIBER MORPHOLOGY Baturalp YALCINKAYA a, Funda CENGİZ CALLIOGLU a a Dept. of Textile E., E.&Arch. Faculty, Süleyman Demirel University - Isparta, Turkey, baturalpyalckaya@hotmail.com, fundaceiz@sdu.edu.tr Abstract Nanofibers have the big potential to crte absolutely ne dustries and application ars. In this study e demonstrated the effect of supporti material type on the fiber morphology such as diameter, diameter distribution and non-fibrous ar. Poly (nyl alcohol) (PVA), molecular eight of g/mol as used as a polymer. Different supporti materials like polypropylen antistatic material,, various oven and knitti fabrics, and alimium foil surface ere used to collect the nanofibers. Nanofibrous materials ere obtaed usi roller electrospni method hich has been knon as Nanospider trade name. This method is one of the effective method to produce nanofibers at dustrial scale hich as vented by Jirsak et. al. from Technical University of Liberec. The same process parameters (solution concentration, voltage, distance beteen the electrodes, production time) ere applied duri the spni process for all supporti materials. Then fiber morphology as analyzed usi scanni electron microscope (SEM) and fiber diameter, diameter uniformity and non-fibrous ar values ere calculated. The best supporti material as determed after analysed the effect of supporti material type on the fiber morphology. Keyords: PVA, roller electrospni, supporti material, nanofiber. 1. INTRODUCTION Electrospni is the most popular and important nano-fabrication technology because of its advantages such as simple set up, spni of ide rae of polymers etc. Needle electrospni as patented by Formhals firstly 1930 yrs [1]. In literature there are many studies about process parameters of needle electrospni method to understand the mechanism and obta optimum properties of nanofibers [2-5]. Hoever there are only limited number of studies about process parameters of roller electrospni [6-7]. Roller electrospni method as vented by Jirsak et al. from Technical University of Liberec 2005 [8]. This method is the unique to produce nanofibers at dustrial scale and as commercialized by Elmarco under the Nanospider trade name. Nanospider can produce membranes collected fibers a rae from 100 to 600 nm of diameter. Such materials are idely utilized many fields; as filtration, hlthcare, buildi construction and many others [6]. The process parameters differ some aspects from needle electrospni method. In this study, e studied the type of supporti material on the collector hich is dependent process parameter of roller electrospni method. In literature, there isn t any study about this subject. The aim of this study is analysi the effect of supporti material on the fiber properties such as diameter, diameter uniformity coefficient and non-fibrous ar percentage. And also e aimed to determe the best supporti material on the collector for fiber properties. 2. EXPERIMENTAL 2.1. Material In this ork, poly(nilalcohol) (PVA) polymer, moleculer eight is g/mol hich as bought from Sigma Aldrich Company as used as a polymer and distilled ater as used as a solvent. All solutions ere prepared under the same conditions such as polymer concentration (10 t % PVA), stirri time etc. Various 1

2 supporti materials such as polypropylen antistatic material,,, till,,, lacoste knitti and alimium foil ere used to collect nanofibers duri the spni process Method Roller electrospni method hich has been knon as Nanospider trade name as used to obta nanofibrous structures. The schematic diagram of this method as given Fig 1. Fig 1. Roller electrospni system Roller electrospni method consists of three ma part; rotati roller, high voltage supplier and collector electrode. A sloly rotati roller partially immersed to the polymer solution tank. Collector is usually grounded and polymer solution is connected to a high voltage supplier. Duri the spni process, polymer solution is taken to the surface of the roller because of its rotation. After sitched on the high voltage supplier, electrical field occurs beteen roller and collector electrode. And many Taylor cones [9] are crted on the roller surface. The nanofibers are then transported toards the collector. The same spni conditions ere proded duri the spni process. These spni conditions such as voltage, distance beteen the electrodes, roller diameter, roller leth and roller speed ere given Table 1. Table 1: Spni Conditions Voltage (kv) Distance beteen collector and roller (cm) Roller diameter (cm) Roller leth (cm) Roller Speed (rpm) All spni experiments ere achieved under the room temperature and humidity and production time 6-8 mute for ch sample. The produced nanofibers ere collected on different supporti materials such as alimium foil, pla,,,,, lacoste knitti and polypropylen antistatic material. Then fiber morphology as vestigated usi a Scanni Electron Microscope (SEM). Fiber diameter, diameter uniformity and non-fibrous ar percentage ere calculated usi Lucia 32G image analyse program. 2

3 , Brno, Czech Republic, EU 3. RESULTS AND DISCUSSIONS Up to no, generally polypropylen antistatic material as used as a supporti material on the collector duri the roller electrospni process [10]. Fig 2 shos, SEM images of nanofibers hich ere collected on different supporti materials. alimum foil lacoste knitti Fig 2. Sem images of nanofibers collected on different supporti materials (x1,000) Accordi to the SEM images of nanofibers, supporti material type has an important effect on fiber morphology. The best fiber morphology as obtaed from and fabric supporti materials. Figure 3 shos the effect of supporti material type on the fiber diameter. Generally fe and uniform nanofibers ere obtaed. Fiber Diameter (nm) ai n pl al im iu m fo il t ill su pr em kn ca it t rb on g bl ac k la pa co pe st r e kn it t no g n ov en 0 Fig 3. The effect of supporti material type on the fiber dimater The loest average fiber diameter value as obtaed from polypropylen fabric (303 nm). Coarse fibers ere obtaed from (461 nm), (461 nm), (457 nm) and 3

4 lacoste knitti (451 nm). It as also given Figure 4, the effect of supporti material type on the fiber diameter uniformity coefficient. 1,0 Diameter Uniformity Coefficient 0,9 0,8 0,7 alimium foil lacoste knitti Fig 4. The effect of supporti material type on the fiber diameter uniformity coefficient. The most uniform nanofibers (uniformity coefficient is 0.97) ere obtaed from fabric as a supporti material. Non-fibrous ar percentage demonstrates the fiber density and refers to the quality of the spni process. Therefore e also analysed the effect of supporti material type on the non-fibrous ar percentage (Fig 5). Non-fibrous ar (%) alimium foil lacoste knitti Fig 5. The effect of supporti material type on the non-fibrous ar percentage The loest non-fibrous ar percentage as obtaed from (1.4 %) and fabric (3.1). The highest non-fibrous ar percentage as obtaed from (25.5 %) and lacoste knitti fabric (27 %). Therefore fiber density is loer collected on these supporti materials and not useful to produce nanofibrous structures for high quality of the spni process. It as also determed, the effect of supporti material type on the fiber diameter, diameter uniformity and non-fibrous ar percentage is important statistically. Another result from the experimental observations is about spni rate crsed usi alimium foil because of high conducitivy of material. Fiber diameter is 420 nm, fiber diameter uniformity is and non- 4

5 fibrous ar percentage is 7.8 % ith alimium foil. It as also seen literature, generally alimium foil as pereferred as a supporti material ith needle electrospni because of its good electric properties [11]. 4. CONCLUSION Roller electrospni method depends on a ide rae of dependent and dependent parameters. Type of supporti material is one of the dependent process parameter and this study effect of supporti material type on fiber morphology as vestigated. Generally nanofibers ere collected on the material shoed good properties terms of diameter, uniformity and non-fibrous ar. The loest average fiber diameter (303 nm) as obtaed from fabric, the most uniform nanofibers (0.970) ere obtaed usi fabric and also the highest fiber density as ell loest non-fibrous ar percentage (1.4) as also obtaed usi fabric. Therefore e can say, type of supporti material has an important effect on fiber morphology obtaed from roller electrospni. The most useful supporti material terms of fiber properties such as diameter, uniformity and non-fibrous ar is and polypropylen material to collect nanofibers duri spni process a roller electrospni. On the other hand;, and lacoste knitti fabrics are not useful supporti materials to collect nanofibers. ACKNOWLEDGEMENT The authors ould like to thank Fatma Yener and Selçuk Çömlekçi for their kd help. REFERENCES [1] Formhals, A., 'Process and Apparatus for Prepari Artificial Thrds', US Patent 1, 975, 504. [2] Deitzel, J. M., Klemeyer, J. D., Harris, D. and Beck Tan, N. C., The Effect of Processi Variables on the Morphology of Electrospun Nanofibers and Textiles, Polymer, 42, [3] Ceiz, F., Krucska, I., Göktepe, F., Gliscska, E. ve Chrzanoski, M., 'An Investigation About the Effects of Process Parameters on Nanofibre Properties Electrospni', Tekstil Maraton Journal, 2006, no:85, [4] Reneker, D. H. and Chun, I., Nanometer Diameter Fibres of Polymer, Produced by Electrospni, Nanotechnology, 7, [5] İkiz, Y., Effect of Process Parameters on Morphology of Electrospun PVA Nanofibers, Pamukkale University, Eeeri Science Journal, 15(3), [6] Dao, A. T., The Role of Rheological Properties of Polymer Solutions Needleless Electrostatic Spni, Ph.D. Thesis, Technical University of Liberec, Czech Republic. [7] Ceiz Çallıoğlu, F. Polyurethane Nanofiber Production by Roller Electrospni Method. Ph.D. Thesis, Süleyman Demirel University, Isparta, Turkey, [8] Jirsak O, Sanetrnik F, Lukas D, Kotek V, Martova L, Chaloupek J., A Method of Nanofibres Production from a Polymer Solution Usi Electrostatic Spni and a Dece for Carryi Out the Method. US Patent, WO [9] Taylor G. I., Distegration of ater drops an electric field. Proceedis of the Royal Society of London. Series A, Mathematical and Physical Sciences, 280, [10] Ceiz, F., Jirsak, O., The Effect of Salt on the Roller Electrospni of Polyurethane. Fibers and Polymers, 10(2), [11] Krissanasaeranee, M., Vosetskul, T., Rakupan, R., Supaphol, P. and Wokasemjit, S., Preparation of Ultra-Fe Silica Fibers Usi Electrospun Poly(Vyl Alcohol)/Silatrane Composite Fibers as Precursor. J. Am. Ceram. Soc., 91 [9],