The melt electrospinning of polycaprolactone (PCL) ultrafine fibers
- PDF / 895,691 Bytes
- 6 Pages / 612 x 792 pts (letter) Page_size
- 43 Downloads / 199 Views
1134-BB08-18
The melt electrospinning of polycaprolactone (PCL) ultrafine fibers Chitrabala Subramanian, Samuel C. Ugbolue*, Steven B.Warner and Prabir K.Patra+ * Department of Materials and Textiles, College of Engineering, University of Massachusetts Dartmouth, MA 02747, USA +
Department of Mechanical Engineering and Materials Science (MEMS), Rice University, 6100 Main Street, Houston, TX 77005, USA
ABSTRACT: Electrospinning is a technique of producing nanofibers from polymer solution/melt solely under the influence of electrostatic forces. In this research, we investigated the formation of nanofibers by melt electrospinning polycaprolactone (PCL). The effect of process parameters such as molecular weight, applied voltage, and electrode separation on the fiber diameter was investigated. Controlling the process parameters could help increase the proportion of ultrafine fibers in the melt electrospun nonwoven mat. The velocity of the straight jets was in the range of 0.2-1 m/s. The melt electrospun fibers were characterized with respect to fiber diameter, distribution, mechanical properties and birefringence. Melt electrospun polycaprolactone fibers had a diameter distribution of the order of 5 -20 µm. The birefringence of the melt electrospun fibers increased with decrease in fiber diameter. 1. INTRODUCTION: Electrospinning process, known since the 1930’s is a technique of producing fine fibers from polymer solution/melt solely under the influence of electric field. In this process a high voltage source charges the polymer solution; the high applied voltage produces surface charge on the droplet and at sufficiently high voltage; the drop elongates to form a Taylor cone and is ejected as continuous stream from the capillary tip. The charged jet is subjected to bending instabilities as it moves towards the grounded collector [1]. A number of polymers have been successfully electrospun from their solutions. Comparatively fewer polymers have been melt electrospun and obtaining nanofibers from polymer melts has not been an easy task [2]. Electrostatic spinning of fibers from polymer melts was first published by Lorrando and Manley in 1981. Their work described spinning of rapidly crystallizing polymer by application of electrostatic field as against conventional methods that use high pressure to extrude the polymer melt in air [3, 4, 5]. Some of the polymers that have been melt electrospun successfully are polypropylene and poly(ethylene terephthalate) [6], polyimide, poly(ethylene naphthalate), poly(caprolactone) and polypropylene in vacuum [7], polyethylene, ethylene vinyl acetate, poly(R,R lactide) [8], block co polymer of poly(ethylene glycol) and poly(ε-caprolactone) [9]. Melt electrospinning of polypropylene by addition of salts or surfactants for charge induction has been tried with the aim of increasing the charge carrying ability that will help in the formation of fine fibers [10]. Modified apparatus designs for spinning plastic polymers at elevated temperatures have been attempted in the past [11-13]. This
Data Loading...
