Hyperbranched polyurethane/triethanolamine functionalizedmulti-walled carbon nanotube nanocomposites as remote induced smart materials

Triethanolamine functionalized multi-walled carbon nanotubes (TEA-f-MWCNTs)/hyperbranched polyurethane nanocomposites were prepared by the in situ polymerization technique. The functionalization of the MWCNTs was confirmed by Fourier transform infrared spectroscopy and Raman spectroscopy studies. The homogeneous distribution and the strong interfacial interaction of TEA-f-MWCNTs with the polyurethane chains were confirmed by transmission electron microscopy and Fourier transform infrared spectroscopy studies, respectively. Significant enhancements of tensile strength (6.5-28.5MPa) and scratch resistance (3-7 kg) with content of TEA-f-MWCNTs (0-2 wt%) were observed. Thermogravimetric analysis showed an increase in thermal stability from 240 to 287 degrees C by the formation of nanocomposites. X-ray diffraction and differential scanning calorimetry studies confirmed an increment in the degree of crystallinity of the nanocomposites with increase in TEA-f-MWCNT content. The extent of shape recovery as well as recovery speed were enhanced with increase in the output power of the microwave. Thus the studied nanocomposites could be utilized as non-contact microwave energy tunable shape memory materials. (C) 2013 Society of Chemical Industry