Effect of dsDNA wrapped single-walled carbon nanotubes on the thermal and mechanical properties of polycaprolactone and polyglycolide fiber blend composites

The aim of this research is to create a stronger biopolymer/carbon nanotube composite suited for load-bearing biomedical applications. Electrospinning was used to fabricate a miscible polycaprolactone (PCL)/polyglycolide (PGA) fiber blend in order to increase the interfacial bonding of the fibers to a PCL matrix. To further increase the strength of the composite, purified single-walled carbon nanotubes (SWNTs) wrapped with double stranded deoxyribonucleic acid (dsDNA) were introduced to the PCL-PGA fibers. Bulk PCL was compression molded to encapsulate the PCL-PGA blended fibers as well as the PCL-PGA/dsDNA-SWNT fibers. Mechanical properties were determined with three-point bend testing to establish the composite's load transfer capabilities. It was demonstrated that incorporation of PCL-PGA/dsDNA-SWNT fibers increased the strength and modulus over that of the bulk PCL and PCL-PGA fibers alone. Furthermore, the use of blended fibers allowed load transfer from the dsDNA-SWNTs to the PCL matrix.