Synthesis of carbon nanotubes and polymers to increase the performance of polymer blends

Nanotechnology has the potential to meet the need for stronger, lighter polymeric materials. Carbon nanotubes introduced into a suitable polymer matrix can be engineered to produce the desired characteristics. Two polymers were focused on in this research, polycaprolactone (PCL) and polyethylene (PE). Polycaprolactones have an extraordinary blend of properties that generate good physical characteristics and low temperature flexibility. Due to its rubbery properties it has been widely used for improving elasticity. PCL has the tendency to form compatible blends with multiple polymers. PCL was chosen primarily because of its ability to be electrospun into fibers. Polyethylene was chosen because of its use in spaceflight applications such as Mars balloons used to conduct scientific research. NASA is in search of new composite materials that will enhance these spaceflight missions. The approach to produce the polymer matrices reported herein employs a range of chemical methods using bench-top level polymer chemistry and carbon nanotubes. Two techniques were studied to produce the desired polymer blends, i.e., electrospinning and extrusion. These techniques were used to obtain homogenous nanopolymer blends and aligned nanopolymer fibers. The samples were studied by scanning electron microscopy and their tensile properties were measured. The properties of the electrospun fibers were studied and an increase in fiber elasticity was observed as the fiber diameter decreased. The extruded polymers displayed over 60% increase in tensile strength with small amounts of carbon nanotubes incorporated within the polymer matrix.