Electromagnetic interference shielding enhancement of poly(lactic acid)-based carbonaceous nanocomposites by poly(ethylene oxide)-assisted segregated structure: a comparative study of carbon nanotubes and graphene nanoplatelets

Abstract

Fabrication of conductive polymer composites with segregated networks is an effective approach in electromagnetic interference (EMI) shielding. In this article, a simple strategy based on the addition of poly(ethylene oxide) (PEO), acting as a binder between carbonaceous nanofillers and poly(lactic acid) (PLA) particles, is proposed. The carbonaceous nanofillers were mixed with small amounts of PEO to prepare the masterbatch, and then the masterbatch was coated on the surface of PLA particles at an appropriate temperature. Finally, the coated PLA particles were hot-pressed to form the PLA-based carbonaceous nanocomposites with a segregated structure. The effects of carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs) on the electrical conductivity and EMI shielding properties of PLA-based nanocomposites, both in segregated and random structures, were compared. For all the nanocomposites, electrical conductivity is always higher in segregated structure than that in random structure. Moreover, the EMI shielding effectiveness (SE) in segregated structure is also higher than that in random structure for all the PLA/GNP nanocomposites and the PLA/CNT nanocomposites with 0.5 to 2 wt% of CNTs. However, for PLA/CNT nanocomposites with 4 to 6 wt% of CNTs, the EMI SE in segregated structure is lower than that in random structure, which is in sharp contrast to the situation of electrical conductivity, due to denser conductive networks in random structure compared to that in segregated structure as demonstrated by the scanning electronic microscopy results. This indicates that the mechanism of EMI shielding is different from that of electrical conductivity.

Improved electromagnetic interference shielding properties of poly (vinylidene fluoride) composites based on carbon nanotubes and graphene nanoplatelets

“…[ 35,36 ] Thus, for PVDF/CNTs/GNPs composite, the improvement of their SE T could be expounded by the addition CNTs and increment in GNPs content, leading to the enhancement in electrical properties. [ 37 ] Moreover, the combination of carbonaceous fillers with different shapes (1D tubular CNTs and 2D sheet GNPs) also improved the conductive network in polymer/filler composites. [ 38,39 ] Detailedly, as the introduction of CNTs and the loading of GNPs increased, numerous moving charge carriers had movability to interact with the incident wave.…”

PVDF-Ni/PE-CNTs Composite Foams with Co-Continuous Structure for Electromagnetic Interference Shielding and Photo-Electro-Thermal Properties

“…It is generally believed that the conductivity of CPCs affects its EMI shielding performance. [40,41] Therefore, as shown in Fig. 3(a), we first studied the electrical conductivity of PVDF-Ni/PE-CNTs composite foams.…”

Facile preparation of a cellulose derived carbon/BN composite aerogel for superior electromagnetic wave absorption

“…[1][2][3] However, the radiation and interference generated by EMW not only threaten human life, but also affect the normal operation of highly sensitive electronic equipment. 4,5 In fact, electromagnetic shielding materials with good microwave reflection properties have been used to solve these problems, 6,7 but the strong electromagnetic reflection generated secondary pollution cannot be avoided. Therefore, it is imperative to design novel materials with excellent EMW absorption properties to convert electromagnetic energy into internal energy or other forms of energy to cut off the propagation of EMW.…”