Paper Number
PM20 

Session
Polymer Melts: From Molecular Rheology to Processing

Title
Wire melt electrospinning of polymers

Presentation Date and Time
October 17, 2018 (Wednesday) 1:55

Track / Room
Track 2 / Plaza I

Authors (Click on name to view author profile)

1. Morikawa, Kai (Texas A&M Univeristy, Aerospace Engineering)
2. Vashisth, Aniruddh (Texas A&M Univeristy, Aerospace Engineering)
3. Naraghi, Mohammad (Texas A&M Univeristy, Aerospace Engineering)
4. Green, Micah J. (Texas A&M University, Chemical Engineering)

Author and Affiliation Lines (in printed abstract book)
Kai Morikawa¹, Aniruddh Vashisth¹, Mohammad Naraghi¹, and Micah J. Green^2
1Aerospace Engineering, Texas A&M Univeristy, College Station, TX 77840; ²Chemical Engineering, Texas A&M University, College Station, TX 77843

Speaker / Presenter 
Morikawa, Kai

Text of Abstract
Polymer fibers are industrially applicable due to their high specific properties. They are used as the building blocks of textiles and fabrics in applications ranging from wearables to reinforcements of composite materials, and liquid/gas filters. These polymer fibers can be processed via a host of techniques, such as extrusion, dry spinning, wet spinning and electrospinning. Many of these processes result in high micron range diameter fibers. There is a desire to reduce the fiber diameter to increase the specific surface area, while in some cases, reducing the diameter may lead to enhanced performance. Electrospinning can be employed to reduce the fiber diameter to sub-micron ranges. Electrospinning uses a potential difference between a spinneret and collector, and the electrostatic forces thin the polymer down as it travels to the collector. Solution electrospinning is used to fabricate nanometer ranged fibers but the resulting fibers contain residual solvent making them unattractive for some applications. In this work, we utilize melt electrospinning using a wire to concentrate the electric field without using solvents throughout the process. Further, carbon nanotubes are embedded in the polymer to enhance the polarizability and reduce the fiber diameter from the electrostatic forces. We applied this method to process polycaprolactone (PCL). Through this wire electrospinning method, PCL fibers with diameters of 3.7 µm were fabricated. We examined the electrospinning jet in our method with those obtained by other approaches, such as syringe based methods. Our method led to melt electrospun fibers which were ~3-4 times thinner than conventional approaches. The generation of thin fibers is based on the concentrated electrostatic fields that developed around the tip of the wire, as alluded to in our finite element models of the electrostatic field around the wire tip. We also demonstrated the utility of the method to synthesize polyethylene fibers with average diameters of ~10 µm.