Covalent grafting of carbon nanotubes to PLA in order to improve compatibility

An excellent methodology for the synthesis of nanocomposite materials using a biodegradable polymer as matrix (polylactic acid, PLA) and functionalized by Fenton reaction carbon nanotubes (fMWCNTs) as reinforcement was developed. PLA was modified with benzoyl chloride and both modified materials were bounded covalently by esterification reaction. Infrared spectroscopy (FTIR) and thermogravimetry (TGA) studies were performed to verify the synthesis of the composites obtained. Films based on modified PLA reinforced with fMWCNTs (PLAmfMWCNTs) were conformed observing excellent dispersion of the filler in the PLA matrix. Finally it was shown that the addition of fMWCNTs improves Young's modulus and strength without losing deformation. Also it was observed that the good stability of the film let us to process it until 300 degrees C. Taking into account all these results, the new biodegradable nanocomposite material developed could be very promising to be used in packaging and biomedical industries as a replacement of the synthetic materials. (C) 2012 Elsevier Ltd. All rights reserved.