Poly[ethylene‐co‐(acrylic acid)]‐based nanocomposites: Thermal and mechanical properties and their structural characteristics studied by Raman spectroscopy

Nanocomposites containing carbon nanotubes (CNTs) as nanofillers and polyethylene‐co‐(acrylic acid)] (PEAA) or a polymer miscible mixture of PEAA and poly(2‐ethyl‐2‐oxazoline) (PEOx) as a matrix were prepared by the solution‐evaporation method with minimal damage to nanotubes. CNTs were prepared by chemical vapor deposition (CVD) with ethanol as the source of carbon. Raman spectroscopy confirmed the presence of single walled carbon nanotubes (SWNTs). High resolution transmission electron microscopy (HRTEM) showed the formation of multi walled carbon nanotubes (MWNTs). Thermal and mechanical properties of the nanocomposites were studied by analyzing samples containing different amounts of CNTs. The degree of crystallinity (X_c) of the PEAA‐based nanocomposite containing a smaller amount of CNTs was larger (X_c = 17.0%) than both the one of pure PEAA (X_c = 14.6 %) and PEAA‐based nanocomposite containing higher amounts of CNTs (X_c = 15.0%). The Young's modulus, ultimate stress, deformation at break, and toughness obtained from unidirectional tensile tests of the CNTs (1 wt%)‐PEAA nanocomposite were higher than both the one of pure PEAA and CNTs (5 wt%)‐PEAA nanocomposite. When a polymer mixture of PEAA/PEOx (containing 80 wt% of PEAA) was used as a matrix, a better mechanical response was also detected for nanocomposite containing 1 wt% CNTs. The nanocomposites containing small amounts of CNTs prepared here have potential to be used as coatings of metal or glass surfaces expecting a better mechanical performance than the one of pure matrix. POLYM. COMPOS., © 2011 Society of Plastics Engineers.