MATERIALE PLASTICE ♦ 52 ♦ No. 2 ♦ 2015 http://www.revmaterialeplastice.ro 180 Equipment for Obtaining Polimeric Nanofibres by Electrospinning Technology II. The obtaining of polimeric nanofibers LILIANA ROZEMARIE MANEA 1* , BOGDAN CRAMARIUC 2 , VASILICA POPESCU 1 , RADU CRAMARIUC 3 , ION SANDU 4,5* , OANA CRAMARIUC 6 1 “Gheorghe Asachi” Technical University Iasi, Faculty of Textile and Leather Engineering and Industrial Management, 29 Dimitrie Mangeron, 700050, Iasi, Romania 2 IT Center for Science and Technology, 25 Av. Radu Beller, Bucharest, Romania 3 Centre of Competence in Electrostatics and Electrotechnologies, 25 Av. Radu Beller, Bucharest, Romania 4 “Alexandru Ioan Cuza” University of Iasi, ARHEOINVEST Interdisciplinary Platform, 11 Carol I, Corp G demisol, 700506, Iasi, Romania 5 Romanian Inventors Forum, 3 Sf.P.Movila Str., L11, III/3, 700089, Iasi, Romania 6 Tampere University of Technology, Department of Physics, P. O. Box 692, FI-33101 Tampere, Finland The computerized technologies and equipment for obtaining nanofibers impose high training, a large interdisciplinary substantiation, capacity for data storage, memorizing, easy usage, selectivity, fiability, stability, reduced time for analizing / processing of the technological parameters. That is why the computerized electrospinning equipment and technologies for obtaining nanofibers are possible candidates to carry out these requirements owing to the fact that they present both the proper selectivity / sensibility and the increased processing /determining /intervening speed by using the computerized control. This paper aims to present the operation and aplication of equipment for obtaining polimeric nanofibers by electrospinning technology. The designing and accomplishing of the suggested electrospinning equipment has been aimed to obtain a modular system which should allow the control of the technological parameters by means of the computer. Thus, the multitude of the parameters which influence the process of electrospinning, can be independently and automatically varied. The obtained nanofibers were studied by scanning electron microscope. Keywords: nanofibers, equipment, technology, modular conception, electrospinning * email: rozemariemanea@yahoo.com; sandu_i03@yahoo.com; Tel.: +40-744-431709 The electrospinning technology involves the application of a very high voltage at one capillary and the polymer solution pumping through the nozzle by using a liquid pump. Nanofibers are collected as a nonwoven material on a grounded collector [1-9]. As a result of the applied voltage it is created a polymer solution jet (named also as melting jet) with a high electrical charge which will form nanofibers by solidification (fig.1). One electrod is placed in the solution and another one is attached by a collector. The polymer fluid from nozzle end, kept by its superficial tension, is electrostatic charged; the mutual rejection of electric charges actions as an opposite force for superficial tension. By increasing the electric field intensity, the fluid hemispherical surface from the nozzle tip changes its length forming a cone named “Taylor cone”. The continuation of the intensity increasing will reach a critical value when the electrostatic rejection force will be greater than superficial tension, and a fluid jet electrical charged will be ejected from the Taylor cone tip [10-13]. In the case of solution electrospinning, the polymer fluid jet begins a process of elongation and rotation so the solvent evaporates, leaving behind a polymer fiber electrically charged with nanoscale dimensions, which will reach randomly or in a linear way the grounded collector [14- 17]. For a certain polymer solution, there are some levels of electric voltage and feeding speed for which the electrospin process can be maintained stable during long periods of time [2, 18-27]. Taking in consideration the jet Fig. 1. Diagram of the electrospinning principle from polymeric solution: 1. proportioning pump; 2. syringe; 3. polymer solution; 4. pipette; 5. Taylor cone; 6. jet (photos of jet fragments at various distances from a capillary); 7. high-voltage source; 8. variable distance; 9. collecting screen, rotary or stationary