Electrical Conductivity and Crystallization of Polylactic Acid Nanocomposites Containing Surfactant Modified Carbon Nanotubes

Abstract

In order to extend the usage of PLA-based nanocomposites, the modification of multi-walled carbon nanotubes (MWCNT) and preparation of surfactant modified carbon nanotubes (SMCNT) involved PLA nanocomposites (PLA/SMCNT) were investigated. The morphologies, electrical properties and crystallization behavior of PLA/SMCNT composites were investigated. The TEM images indicated that SMCNTs were dispersed homogenously in the PLA matrix without forming aggregates. The electrical conductivity of PLA/SMCNT was greatly improved and the percolation threshold of PLA/SMCNT was calculated to be 0.61% which is much lower than 1.45% of PLA/MWCNT composite. The crystallization behavior suggested that SDBS together with MWCNT acted as heterogeneous nucleating agent and accelerated the nucleation. Meanwhile, the SMCNT also devoted further restrained effect to spherulites growth due to its well dispersion and improved compatibility with matrix.