Improved mechanical and barrier properties of Natural rubber-Multiwalled carbon nanotube composites with segregated network structure

Natural Rubber (NR) composites containing segregated network structure of Multiwalled carbon nanotubes (MWCNT) were prepared by ultrasonication assisted latex stage mixing technique. The preparation involved acidic treatment of the nanotubes prior to ultrasonication in order to get carboxylated MWCNTs (MWCNTR). The final composites contained segregated network of carbon nanotubes. The presence of segregated structure was confirmed by Transmission electron microscopy (TEM). The NR-MWCNTR composites prepared exhibited excellent mechanical and gas barrier properties with improved solvent resistance and cross-link density at very low concentration of nanotubes which can be attributed to the segregated network present in the composites. The cellular structure and occluded rubber due to the confinement of rubber within the networks in the NR-MWCNTR composite provided tremendous reinforcement. The Thermogravimetric analysis (TGA) showed that the added nanotubes did not alter the thermal stability of the composites