Electrospun Non-Woven Mats as Substrates for Flexible Electronics

Student’s name: Connor Denney Home Institution: Somerset Community College NNCI Site: KY Multiscale @ Uof L Abstract: Electrospinning is a manufacturing technique that can produce non-woven mats from polymeric solutions (e.g., polyacrylonitrile (PAN) 10%). It has shown potential to produce fine resolution fibers on the order of 40-50 micrometers and can be used for various applications such as electronics and filtering. Due to high areal surface, these non-woven mats could potentially benefit the sensitivity and performance of flexible electronics (e.g., strain gauge sensors, wearable sensors, etc.) Thus, the purpose of this study is to analyze the feasibility of printing conductive lines on top of the electrospun flexible substrate. Extensive screening of the electrospinning process parameters was done and it was determined that optimal conditions for the strongest substrates were: a distance of 13 cm, a flowrate of 0.40 mL/hr, and a voltage of 6.7 kV. The flexible substrate is manufactured using these parameters for 5 hours. A conductive design can be printed on the top of the substrate using additive manufacturing processes. Aerosol Jet Printing (AJP) with silver conductive ink was used in this case. The substrates were then baked on a hot plate at 200°C for five minutes. To improve the properties of the printed conductive lines, the substrates were cured the print patterns via Intense Pulsed Light (IPL) treatment. The entirety of the printing process was repeated in order to have one, two, and three layers of conductive ink. The results showed that the printed lines were conductive after curing. Further research to investigate and quatify the conductivity for different electrospinning solutions and AJP inks will be performed.