Thermal and kinetic properties of poly(vinylacetate)/modified MWCNT nanocomposites

Abstract

The aims of this study were to improve the low thermal stability of poly(vinylacetate) (PVAc) polymer by forming its nanocomposite products according to solvent casting method with multi-walled carbon nanotube (MWCNT) and/or modified (functionalized) MWCNTs, and to perform thermal kinetics analysis of the thermal properties improved nanocomposites. Functionalization of p-MWCNTs (purified MWCNT) was carried out by hydroxylation, carboxylation and silylation reactions. The effects of the surface modification, the type of functional groups and the filler ratio to the thermal properties of the nanocomposites were investigated. The synthesized nanocomposites were characterized by Fourier transform infrared spectrum, differential thermal analysis-thermogravimetry (DTA/TG) and scanning electron microscope (SEM). It was found that; (i) the p-MWCNT was modified, (ii) the carbon nanotubes were dispersed in the tube structure in the PVAc matrix, (iii) the thermal stabilities, degradation temperatures (T (max1) and T (max2)) and T-x values of PVAc/p-MWCNT-COOH (1 wt%) and PVAc/p-MWCNT-O-APTS (0.5 wt%; APTS: 3-aminopropyltriethoxysilane) nanocomposites were increased, (iv) the experimental results were quite compatible with the Flynn-Wall-Ozawa method and (v) the activation energy of the second step was higher.