Effects of silicon carbide nanoparticles and multi‐walled carbon nanotubes on water uptake and resultant mechanical properties degradation of polymer nanocomposites immersed in hot water

Polymeric materials are prone to moisture attack when they are immersed in water or exposed to moisture. This paper aims to study the effects of multi‐walled carbon nanotubes (MWCNT) and silicon carbide (SiC) nanofillers on reinforcing the epoxy polymer against water uptake and resultant degradations of mechanical properties. Therefore, the neat epoxy and nanocomposite samples containing various weight percentages of nanofillers were fabricated and immersed in deionized hot water. The gravimetric measurements over various time intervals showed that adding MWCNTs and SiCs to epoxy caused the polymer water uptake to decrease by 50% and 46%, respectively, at initial stage of water absorption and by 26% and 18% at saturation. The epoxy water diffusion rate was reduced by 58.4% and 56.9% when MWCNTs or SiCs were introduced into the polymer, respectively. Moreover, the epoxy strength degradation due to water uptake was declined by 32% and 16% when MWCNTs and SiCs were added into the polymer, respectively, at saturation. Whereas, the epoxy stiffness degradation of the epoxy/MWCNTs and epoxy/SiCs nanocomposites were 27% and 19% lower than the neat epoxy, respectively. Furthermore, water uptake in the neat epoxy and nanocomposites was modeled using a finite element model. POLYM. COMPOS., 39:E883–E890, 2018. © 2017 Society of Plastics Engineers