A Novel Method for Measurement of Porosity in Nanofiber Mat using Pycnometer in Filtration

Electrospun Polymer nanofibers have a wide range of applications including automotive air filters. Large surface area, small pores, flexible and adequate porosity are widely recognized as important parameters for improving the performance of the filter media and therefore measuring the porosity of the medium is extremely important. Porosity measurement techniques such as density based method, mercury porosimetry, capillary flow porometry, image analysis are relatively inaccurate and they have some disadvantages for measuring the porosity of the nano fibers. In the present study porosity measurement for nanofiber mat using pycnometer was explored. Pycnometer is generally used to measure the density of the solids of having volumes upto 150 cc. Volume of the nanofiber was measured by pycnometer and porosity is determined as fraction of the void in total volume of the fiber. Total volume is calculated from FESEM image thickness. Various advantages of pycnometry method when compared to other techniques were discussed based on the results of porosity measurements of nanofiber mats.