The effect of natural rubber toughening on mechanical properties of poly(lactic acid)/ multiwalled carbon nanotube nanocomposite

Abstract

Investigation was done on the use of natural rubber (NR) as impact modifier in polylactic acid (PLA) nanocomposite containing carboxylic functionalized multiwalled carbon nanotubes (MWCNT) as nanofillers. NR toughened PLA nancomposite consisting of 1 phr MWCNT and NR contents varies from 5 to 20 wt% were prepared by direct melt blending in a counter-rotating twin-screw extruder followed by injection moulding into test specimens for mechanical properties analysis. The tensile, flexural and impact test analysis were carried out to investigate the mechanical properties of PLA/NR/MWCNT nanocomposites at different loading of NR. As comparison, pure PLA, PLA/NR with 5 wt% NR and PLA/MWCNT with 1 phr nanotubes were also prepared with similar method. Results indicated that introduction of NR into PLA/MWCNT contributed to significant improvement in impact strength and ductility of the nanocomposite. Moreover, the deterioration effect of nancomposites stiffness, mechanical and flexural strength due to the introduction of NR was minimized with the presence of MWCNT in the nanocomposite system.