Morphology, Thermal, and Rheological Behavior of Nylon 11/Multi-Walled Carbon Nanotube Nanocomposites Prepared by Melt Compounding

Nylon 11 (PA11) nanocomposites with different loadings of multi-walled carbon nanotubes (MWNTs) were prepared by melt compounding. Scanning electron microscopy images on the fracture surfaces of the composites showed a uniform dispersion of MWNTs throughout the matrix. The presence of the MWNTs significantly improved the thermal stability and enhanced the storage modulus (G) of the polymer matrix. Melt rheology studies showed that, compared with neat PA11, the incorporation of MWNT into the matrix resulted in higher complex viscosities (vertical bar eta*vertical bar), storage modulus (G'), loss modulus (G ''), and lower loss factor (tan delta). PA11 and its nanocomposites containing less than 1 wt% MWNTs showed similar frequency dependencies and reached a Newtonian plateau at low frequencies. For the nanocomposite with 2 wt% MWNTs, the regional network was destroyed and the orientation of the MWNTs during shearing exhibited a very strong shear thinning effect. The complex viscosities (vertical bar eta*vertical bar) of the nanocomposites are larger than that of neat PA11 and decreased with increasing the temperature. POLYM. ENG. SCI., 49:1063-1068, 2009. (C) 2009 Society of Plastics Engineers