Polyethylene/Graphene Nanoplatelet Nanocomposite-Based Insulating Materials for Effective Reduction of Space Charge Accumulation in High-Voltage Direct-Current Cables

Abstract

We have demonstrated a straightforward hydrophobic surface modification of graphene nanoplatelets (GNPs) through a defect-healing process to fabricate well-dispersed insulating low-density polyethylene (LDPE)/GNP nanocomposites and have confirmed their effective suppression of space charge accumulation. Without any organic modifiers, GNPs containing oxygen-based functional groups at the edges were successfully reduced at optimal high-temperature defect-healing condition and modified to have hydrophobic surface properties similar to those of the LDPE matrix. The degree of dispersion and the reproducibility of the mechanically melt-mixed LDPE/GNP nanocomposites were immediately analyzed by thickness-normalized optical absorption measurement. In the LDPE matrix, below the percolation threshold concentration, well-dispersed GNP fillers effectively acted as trapping sites under high electric fields, resulting in the successful suppression of packet-like space charge accumulation (field enhancement factor=1.04 @ 0.1 wt% LDPE/GNP nanocomposite).

Development of waste tire‐derived graphene reinforced polypropylene nanocomposites with controlled polymer grade, crystallization and mechanical characteristics via melt‐mixing

“…It is important to note that the changes in the structure of the polymer and the presence of a second phase such as graphene can affect the mechanical and thermal properties of graphene based composites. Although several authors have studied the effect of GNPs on the characteristics of various polymeric composites, [17][18][19][20][21] to the best of our knowledge, there is no related work that investigates how the polymer grades and graphene content affect the mechanical and thermal characteristics of graphene based PP nanocomposites simultaneously and systematically. In this work, GNP reinforced Homo-PP and copolymer PP (Copo-PP) nanocomposites were fabricated by the melt compounding technique and the effects of different amounts of GNPs as well as the type of polymer grade on the mechanical, thermal and structural properties of the composite were examined in detail.…”

Influence of polar and unpolar silica functionalization on the dielectric properties of PP/POE nanocomposites

“…Nanodielectrics have drawn a lot of attention in the High Voltage Direct Current (HVDC) field [1,2,3]. It is reported that adding a nanofiller to dielectrics can suppress space charge accumulation [1,2] and improve the breakdown strength [3]. However, the dispersion of a nanofiller in a polymer matrix is a major challenge.…”

“…However, the dispersion of a nanofiller in a polymer matrix is a major challenge. Polyethylene or polypropylene feature an unpolar nature; hence, in order to increase the compatibility and dispersibility of a polar filler with the polymer matrix, an unpolar functionalization is needed [1]. However, it is also reported [2] that the introduction of various polar functional groups into nanocomposites results in an improvement of dielectric properties.…”

Improving the Hydrophobicity and Insulation Properties of Epoxy Resins by the Self-Assembly-Induced Coating of Fluorinated Graphene

“…However, nanofillers tend to agglomerate with increased storage time, resulting in surface charge accumulation. Moreover, local electric field distortion easily reduces the dielectric strength, resulting in local charge accumulation . Therefore, for hydrophobic insulation materials used in electronic packaging, both hydrophobicity and insulation should be improved simultaneously.…”

“…Moreover, local electric field distortion easily reduces the dielectric strength, resulting in local charge accumulation. 10 Therefore, for hydrophobic insulation materials used in electronic packaging, both hydrophobicity and insulation should be improved simultaneously. Fluorinated graphene (FG) is a two-dimensional carbon nanostructure formed via the partial or full fluorination of the carbon atoms in graphene.…”