Morphology and thermal properties of clay based biocomposites

Abstract

Abstract Carboxymethylcellulose/poly(ethylene glycol) (CMC/PEG) blend and CMC/PEG/montmorillonite (MMT) nanocomposites were produced by the solvent casting method. The clay, a sodium MMT, was incorporated in the polymer matrix at low weight loadings (from 1 wt% to 7 wt%). The MMT dispersion in the matrix was evaluated by X-ray diffraction, which revealed an intercalated structure of the nanocomposites. Different levels of intercalation have been detected. The changes in morphology caused by the addition of layered silicate on CMC/PEG blend were investigated by scanning electron microscopy (SEM). The SEM images of CMC/PEG blend containing 5% of MMT displayed more homogenous morphology than CMC/PEG blend. The compatibilizing performance of the filler was investigated using differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and Fourier transform infrared (FTIR) spectroscopy. The effect of the introduction of the clay on the crystallization temperature, melting temperature and crystallization degree of CMC/PEG revealed that clay behaved as a nucleating agent and enhanced the crystallization rate of PEG. Furthermore, it was demonstrated that the addition of a small percentage of montmorillonite (1%) was enough to improve the thermal stability of the nanocomposites.