Effect of organoclay content on the mechanical properties of ethylene-vinyl acetate copolymer/multi-walled carbon nanotube/organoclay foams

The main objective of this study is to obtain ethylene-vinyl acetate copolymer (EVA)/multi-walled carbon nanotube (MWCNT)/organoclay foams with improved mechanical properties without increase of their density, compared with EVA/MWCNT foams. MWCNT content was fixed at 5 phr in this study. To achieve the objective, EVA was melt-mixed with MWCNTs and organoclays in a bench kneader. And the obtained EVA/MWCNT/organoclay mixtures were mixed with chemical blowing agent and cross-linking agent in a two roll-mill. After being mixed in a two roll-mill, the mixtures were put in a mold and the foams were obtained by compression-molding. The effect of organoclay content on the mechanical properties and surface resistivity of EVA/MWCNT (5 phr)/organoclay foams was investigated. The addition of 1 phr organoclays to the EVA/MWCNT (5 phr) foams resulted in the improvement of tensile strength, 100% tensile modulus, tear strength, and compression set without increase of the density. However, further increase in content of organoclay (3 phr) leaded to a deterioration of mechanical properties. Therefore, determining the optimal content of organoclay was very important in order to achieve the main objective of this study. POLYM. COMPOS., 2013. (c) 2013 Society of Plastics Engineers