Nanofiber Research

Polymeric Nanofibers, Nanofibrous Layers, Nanofiber Yarns & Nanoparticles

Jitka Färberová

Department of Nonwoven Textiles, Nanoscience Centre, Faculty of Textile Engineering, Technical University of Liberec, Czech Republic

"Working with the Phenom and FiberMetric system gives us very fast, accurate and well-presented results."

The Department of Nonwovens at the Technical University of Liberec runs courses in production technology, evaluation and innovative methods in nonwoven textile production and technical textiles. Research activities involve the testing and analysis of nonwoven textile structures including electrospinning products consisting of nanofibers. Nanofibers are defined as fibers having diameters of the order of 100 nanometers and can be produced by various methods, including interfacial polymerization and electrospinning.

Researching nonwovens using the Phenom SEM and Fibermetric
Jitka Färberová: “Working with the Phenom and Fibermetric system gives us very fast, accurate and well-presented results.”

We have several years of experience with electrospinning and more than 40 years of experience with other nonwoven technologies. We are able to spin several polymeric materials and melts with various structures. The morphology is analyzed preferentially using electron and optical microscopic techniques. One of the microscopes used is the Phenom™ scanning electron microscope.

Poly (lactic-co-glycolic acid) nanofibers with beeds using Phenom SEM
Poly (lactic-co-glycolic acid) nanofibers with beads. Phenom SEM image size: 120 µm. 

The main research and scientific activities of the department are focused on:

  • Development of electrospinning technology, application of electrospun materials and complex theoretical research in this area;
  • Interactions between fiber assemblies and liquid phases (filtration, sorption), including computer modeling;
  • Physiological and thermal properties of textiles;
  • Compressional properties of textiles;
  • Technology and devices for highloft perpendicular-laid nonwovens (STRUTO);
  • Melt-blown technology, fabric modifications and electrospinning for the production of nanofibers.

Applications of Nanofibers

Filtration

Filtration is one of the most important applications of nanofiber materials. One section of the laboratory is fully equipped for the detailed testing and analysis of filtration properties of special materials. The department also offers lab and pilot-plant production of small amounts of specialized materials for property testing.

Polyvinyl alcohol nanofiber layer with Phenom SEM

Polyvinyl alcohol nanofiber layer. Phenom SEM image size: 48 µm.

Acoustic Applications

An important property of nanofibrous materials is their high acoustic absorption, especially in the low-frequency range of sound waves, where all other materials either fail or are less effective. Nanofibrous materials seem to have extraordinary promise as acoustic barriers in many applications.

Medical and Biological Applications

There has been a strong focus over recent decades on the use of nanofibrous materials for medical applications. These materials have ideal properties for tissue engineering. Coaxial electrospinning is a promising technique employed to produce core-shell fibers which can be used for drug delivery applications.

Polycaprolactone nanofibers with beeds imaged by Phenom SEM
Polycaprolactone nanofibers with beads. Phenom SEM image size: 48 µm.

Advantages of the Phenom SEM

The Phenom scanning electron microscope has improved our work flow and research programs. Whereas in the past, we had to wait an annoying time for obtaining images from an electron microscope. Microphotographs are now available for us in heretofore unbelievable short time comparable with light microscopy technology. The magnification range of the Phenom desktop scanning electron microscope is very suitable for studying the structure of nanofiber layers and of single fibers. Furthermore, our Phenom is so easy to operate that students can use it without the need of time consuming special training. This was the main reason for choosing the Phenom.

Benefits of Automated Fiber Analysis for Nanofibers

Used in conjunction with the FiberMetric™ software, the Phenom enables fast measurement of nanofiber and pore diameters. Measurement of these parameters is automatic, so it speeds up our work and saves time. Measured values are as accurate as those obtained from manual measurements using special image analysis software. We enjoy a great advantage having the Phenom and the FiberMetric together in one place as it allows us to obtain complete sample information in the same session. Another advantage is that the FiberMetric software generates statistical data and frequency diagrams of the measured diameters.

3D nanofiber layer cross-section with Phenom SEM
3D nanofiber layer cross-section. Phenom SEM image size: 241 µm.