Physico–mechanical properties of poly(ethylene‐co‐vinyl acetate)/acrylonitrile‐butadiene rubber/multi‐walled carbon nanotubes nanocomposites

Abstract The influence of multi‐walled carbon nanotubes (MWCNTs) on thermal, mechanical and wetting properties as well as rheological behavior of poly(ethylene‐co‐vinyl acetate) (EVA)/acrylonitrile‐butadiene rubber nanocomposites were studied. The solid surface free energy (), work of adhesion (), interfacial free energy (), spreading coefficient () and Girifalco‐Good's interaction parameter () were calculated for the materials fabricated. The results showed that the contact angle and decreased; however, , , , and increased with the increase in MWCNTs content. The maximum tensile strength and toughness were obtained for the nanocomposite containing 1 wt% nanofillers. It was also found that both of the relaxation ratio (Rr) and relaxation rate index ( n ) decreased with increasing in the carbon nanotubes (CNTs) concentration. The results designated that the values of Rr and n for the nanocomposite containing 7 wt% MWCNTs were 19% and 60% smaller than those of the unfilled blend, respectively. The Casson plot analysis indicated that the yield stress of the molten materials incremented with the increase in MWCNTs loading according to a quadratic equation. The analysis of crystallization exotherms and melting endotherms revealed that CNTs triggered the crystallization process at slightly higher temperature, however, melting point slightly and the rate of nucleation noticeably reduced with the increase in the nanofillers content.