Production and characterization of polycaprolactone nanofibers via forcespinning™ technology

Abstract

Among the myriad of methods for polymer nanofiber production, there are only a few methods that can produce submicron range fibers in bulk from melt or solution samples. The Forcespinning TM method allows a substantial increase in sample yield while simultaneously maintaining the integrity of uniform fibers in the nanometer range. The high production yield of such a method greatly reduces the time needed to produce bulk quantities of fibers which may be critical in many fields of research and industry, in particularly in fields relating to biopolymers. The aim of this study was to use this method to form nonwoven mats of polycaprolactone (PCL) nanofibers and to quantitatively analyze the production and char-acterization of the produced fibers. The bulk PCL was dissolved in dichloromethane and the solutions were forcespun at varying speeds ranging from 3000 to 9000 rpm. It was observed that fiber diameter decreased with increasing rotational speed. The average fiber diameter at 9000 rpm was 220 nm with a standard deviation of 698 nm. The morphology and degree of crystallinity were characterized by scanning electron microscopy, differential scanning calorimetry, and X-ray diffraction.

Research on the development of the centrifugal spinning

“…Electrostatic force makes the material stretched, when the surface tension is overcome, a jet is ejected from the spinneret, then the jet undergoes a spiral trajectory and finally the jet arrives the collector. Although there are many virtues to the electrospinning process, the low fiber production rates, high voltage (5kV~60kV), solvent limitations and so on make it unable to large scale commercial use [7][8][9][10]. In recent years, some progresses have been made to increase the production rate of electrospinning.…”

Centrifugal melt spinning of polyvinylpyrrolidone (PVP)/triacontene copolymer fibres

“…It is proposed that a combination of these factors contributes to generating fibres with a range of fibre diameters significantly greater than the reported mean value. It has been previously reported that mean fibre diameter of centrifugal spun fibres decreases with spinning duration and it is proposed that a continuous machine would create a lower proportion of coarse fibres as the effects of acceleration and deceleration are minimised [15].…”

“…This technique involves rotating polymer fluids at high speeds to induce jet formation and elongation without the need for external drawing, electrostatic forces or high velocity hot air [14]. It has been demonstrated that centrifugal spinning can readily produce fibres finer than 1 lm from a variety of polymer materials [14,15] from either thermoplastic liquid melts or solutions. Fibres have been produced from conventional thermoplastics such as nylon and polyester; speciality polymers such as polycaprolactone and poly(lactic acid); bismuth; ceramic materials; compounds of polypropylene and carbon nanotubes; compounds of poly(ethylene terephthalate) with graphene [13,16,17].…”

“…Fibres have been produced from conventional thermoplastics such as nylon and polyester; speciality polymers such as polycaprolactone and poly(lactic acid); bismuth; ceramic materials; compounds of polypropylene and carbon nanotubes; compounds of poly(ethylene terephthalate) with graphene [13,16,17]. In centrifugal spinning, the operating conditions can have a significant influence on fibre diameter and investigation is often necessary to establish optimum parameters, balancing fibre fineness and the level of beading [15].…”

Rotary jet spinning review – a potential high yield future for polymer nanofibers

“…Applications and future research directions into nanofibers including RJS fibers are attributed to a few key areas of interest, namely filtration, 3 healthcare, environmental engineering, biotechnology, composites, 121 defense and security and the energy sectors. 143 Many researchers have started studies into RJS nanofibers driven by applications within specific sectors such as medicine, where fibers resemble cellular topographies 63 or are capable of targeted outcomes such as drug delivery. 68 Others have focused on using conjugated polymers in the RJS process for areas such as photovoltaic cells, light-emitting diodes, and biocompatible materials.…”