Processing-property relationships of biaxially stretched binary carbon nanofillerreinforced high density polyethylene nanocomposites

Different dimensional carbon nanofillers, such as carbon nanotubes (CNTs), graphenenanoplatelets (GNPs) and carbon black (CB), are often incorporated into polymers in a hybrid form to fabricate multifunctional nanocomposites. In this paper, biaxial stretching of binary carbon nanofiller reinforced high density polyethylene (HDPE) nanocomposites was carried out at various stretching ratios in order to investigate the influence of carbon nanofillers on material deformation behaviour and the influence of biaxial deformation on the structure and properties of the deformed material. It is shown that the strain hardening behaviour of nanocomposites upon biaxial stretching is gradually enhanced with increasing aspect ratios of the nanofillers. The deagglomeration and reorientation of nanofillers in the polymer matrix can be observed during deformation. Furthermore, biaxial stretching significantly affects the final tensile, electrical and barrier properties of the deformed nanocomposites, depending on the components of carbon nanofillers introduced. The stretched HDPE/GNP/CNT and HDPE/GNP/CB nanocomposites exhibit greatly improved tensile and barrier properties.