Influence of Processing on Morphology, Electrical Conductivity and Flexural Properties of Exfoliated Graphite Nanoplatelets-Polyamide Nanocomposites

Abstract

Graphene is one of the most promising materials for many applications. It can be used in a variety of applications not only as a reinforcement material for polymer to obtain a combination of desirable mechanical, electrical, thermal, and barrier properties in the resulting nanocomposite but also as a component in energy storage, fuel cells, solar cells, sensors, and batteries. Recent research at Michigan State University has shown that it is possible to exfoliate natural graphite into graphite nanoplatelets composed entirely of stacks of graphene. The size of the platelets can be controlled from less than 10 nm in thickness and diameters of any size from sub-micron to 15 microns or greater. In this study we have investigated the influence of melt compounding processing on the physical properties of a polyamide 6 (PA6) nanocomposite reinforced with exfoliated graphite nanoplatelets (xGnP). The morphology, electrical conductivity, and mechanical properties of xGnP-PA6 nanocomposite were characterized with electrical microscopy, X-ray diffraction, AC impedance, and mechanical properties. It was found that counter rotation (CNR) twins crew processed xGnP/PA6 nanocomposite had similar mechanical properties with co-rotation (CoR) twin screw processed or with CoR conducted with a screw design modified for nanoparticles (MCoR). Microscopy showed that the CNR processed nanocomposite had better xGnP dispersion than the (CoR) twin screw processed and modified screw (MCoR) processed ones. It was also found that the CNR processed nanocomposite at a given xGnP content showed the lowest graphite X-ray diffraction peak at 26.5 o indicating better xGnP dispersion in the nanocomposite. In addition, it was also found that the electrical conductivity of the CNR processed 12 wt.% xGnP-PA6 nanocomposite is more than ten times higher than the CoR and MCoR processed ones. These results indicate that better dispersion of an xGnP-PA6 nanocomposite is attainable in CNR twins crew processing than conventional CoR processing.

Processing–morphology–property relationships of polypropylene–graphene nanoplatelets nanocomposites

“…This increase was taken to be an indication of an increasing nucleating efficiency with the addition of GNPs to the PP matrix, as reported elsewhere . A sharp peak around 26.5° appearing for the PP/GNPs nanocomposites was assigned to the graphene (002) diffraction peak . In a comparison of the XRD patterns of the PP/GNPs nanocomposites prepared by the die with and without shunt plates, we observed that the (002) diffraction peak intensity of the nanocomposites prepared by the die with shunt plates was stronger than that by the die without shunt plates.…”

Effects of ultrasound vibration on the structure and properties of polypropylene/graphene nanoplatelets composites

“…The sharp peak around 17.1° appears for the PP/GNPs nanocomposites is the PP (040) diffraction peaks. While the sharp peak around 26.5° can be assigned to the graphene (002) diffraction peak , whose obvious increase can be attributed to the increasing of GNPs. Comparing the XRD patterns of PP/GNPs nanocomposites extruded without and with ultrasound treatment, as shown in Fig.…”

Phenylethynyl-terminated polyimide, exfoliated graphite nanoplatelets, and the composites: an overview

“…In recent years, many research efforts have been devoted to studying the effect of carbon nanoparticles, such as xGNP and carbon nanotubes, on the mechanical, thermal, and/or electrical properties of various polymers [80][81][82][83][84][85][86][87][88]. Fig.…”