Enhanced Functional Properties of Low-Density Polyethylene Nanocomposites Containing Hybrid Fillers of Multi-Walled Carbon Nanotubes and Nano Carbon Black

Abstract

In this work, hybrid filler systems consisting of multi-walled carbon nanotubes (MWCNTs) and nano carbon black (nCB) were incorporated by melt mixing in low-density polyethylene (LDPE). To hybrid systems a mixture of MWCNTs and nCB a mass ratio of 1:1 and 3:1 were used. The purpose was to study if the synergistic effects can be achieved on tensile strength and electrical and thermal conductivity. The dispersion state of carbon nanofillers in the LDPE matrix has been evaluated with scanning electron microscopy. The melting and crystallization behavior of all nanocomposites was not significantly influenced by the nanofillers. It was found that the embedding of both types of carbon nanofillers into the LDPE matrix caused an increase in the value of Young’s modulus. The results of electrical and thermal conductivity were compared to LDPE nanocomposites containing only nCB or only MWCNTs presented in earlier work LDPE/MWCNTs. It was no synergistic effects of nCB in multi-walled CNTs and nCB hybrid nanocomposites regarding mechanical properties, electrical and thermal conductivity, and MWCNTs dispersion. Since LDPE/MWCNTs nanocomposites exhibit higher electrical conductivity than LDPE/MWCNTs + nCB or LDPE/nCB nanocomposites at the same nanofiller loading (wt.%), it confirms our earlier study that MWCNTs are a more efficient conductive nanofiller. The presence of MWCNTs and their concentration in hybrid nanocomposites was mainly responsible for the improvement of their thermal conductivity.

Functional Properties of Kenaf Bast Fibre Anhydride Modification Enhancement with Bionanocarbon in Polymer Nanobiocomposites

“…The carbon nanostructure probably filled up possible hollow or void space in the composites, resulting in a compacted product. It means that the composite mass increased with the bionanocarbon loading while still occupying the same volume, which results in a higher density [ 53 ].…”

Comparing Multi-Walled Carbon Nanotubes and Halloysite Nanotubes as Reinforcements in EVA Nanocomposites

“…No effect of CNTs on the nucleation of polymer crystals has also been reported in some cases [ 56 , 57 ]. More recently, LDPE/CNTs nanocomposites have been prepared in our research group [ 58 ]. Our results show that crystallization behavior of PE in LDPE/CNT nanocomposites was not influenced by the presence of CNTs.…”

“…Similar as in LDPE/CNTs nanocomposites, it can be a result of a low value of surface energy and a poor wettability of CNTs. This means that it can be difficult for them to induce aggregation of polymer chains on their surfaces [ 58 ]. In turn, the increase in T g results from the fact that CNTs may prevent the mobility of the copolymer chains, leading to an increase in T g [ 50 ].…”

Preliminary investigation on the correlation between mechanical properties and conductivity of low-density polyethylene/carbon black (LDPE/CB) conductive polymer composite (CPC)

“…A higher filler loading normally will be lowering the mechanical properties of the composites. According to S. Paszkiewicz [15], nanocomposites with CB nanoparticles had slightly lowered the tensile strength and strain at break of the composite when comparing with pure LDPE. Elongation at break is one of the important parameters to indicate the ductility or fracture toughness of materials [16].…”