Effects of Chemical Functionalization of MWCNTs on the Structural and Physical Properties of Elastomeric Copolyetherester-based Composite Fibers

Elastomeric copolyetherester (CPEE)-based composite fibers incorporating various neat and functionalized multiwalled carbon nanotubes (MWCNTs) were prepared through a conventional wet-spinning and coagulation process. The influence of functionalized MWCNTs on the morphological features, and the thermal, mechanical properties and electrical conductivity of CPEE/MWCNT (80/20, w/w) composite fibers were investigated. FE-SEM images show that a composite fiber containing poly(ethylene glycol)-functionalized MWCNTs (MWCNT-PEG) has a relatively smooth surface owing to the good dispersion of MWCNT-PEGs within the fiber, whereas composite fibers including pristine MWCNTs (p-MWCNT), acid-functionalized MWCNTs (a-MWCNT), and ethylene glycol-modified MWCNTs (MWCNT-EG) have quite a rough surface morphology owing to the presence of MWCNT aggregates. As a result, the CPEE/MWCNT-PEG composite fiber exhibits noticeably increased thermal and tensile mechanical properties as well as a faster crystallization behavior, which stems from an enhanced interfacial interaction between the CPEE matrix and MWCNT-PEGs.