Electrical and Mechanical Properties of Poly(L-lactide)/Carbon Nanotubes/Clay Nanocomposites

초록

An organoclay with epoxy groups, namelr twice functionalized organoclay (TFC), was successfully synthesized by reacting (glycidoxypropyl)trimethoxy silane with Cloisite25A (C25A) which hadalready been modified with an amino compound. By the introduction of epoxy groups on the clay surface and carboxvlic group functionalized CNTs, the interfacial adhesion between poly(L-lactide) (PLA) and nano-sized filers was improved when they were melt-compounded. The mechanical properties of the PLA/CNTS/TFC nanocomposites were improved than those of PLA and PLA/CNTS. The dispersion of the CNTs in the PLA matrix resulted in a substantial decrease in the electrical resistivity of the composite as the MWCNTS loading was increased. However, the volume resistivity was notably increased when the TFC were introduced to PLA/CNTS nanocemposites. This was attributed to the fact that the individual CNTs were block with TFC. The CNTs in the PLA/CNTS/TFC nanocomposites hindered the direct contact between neighboring MWCNTS, and this might be the reason for the decrease in the electrical conductivity of the nanecomposites. The morphology of PLA/CNTs/TFC composites is observed by scanning electron microscopy and transmission electron microscopy.