Dielectric Properties of Wood-Polymer Composites: Effects of Frequency, Fiber Nature, Proportion, and Chemical Composition

Abstract

The characterization of the dielectric properties of wood–polymer composites (WPCs) is essential to understand their interaction with electromagnetic fields and evaluate their potential use for new applications. Thus, dielectric spectroscopy monitored the evolution of the dielectric properties of WPCs over a wide frequency range of 1 MHz to 1 GHz. WPCs were prepared using mixtures of different proportions (40%, 50%, and 60%) of wood and bark fibers from various species, high-density polyethylene, and maleated polyethylene (3%) by a two-step process, extrusion and compression molding. Results indicated that wood fibers modify the resistivity of polyethylene at low frequencies but have no effect at microwave frequencies. Increasing the fiber content increases the composites’ dielectric properties. The fibers’ cellulose content explains the variation in the dielectric properties of composites reinforced with fibers from different wood species. Indeed, composites with high cellulose content show higher dielectric constants.

Effects of Particle Size on the Dielectric, Mechanical, and Thermal Properties of Recycled Borosilicate Glass-Filled PTFE Microwave Substrates

“…The variation of and ′′ in the 1-12 GHz range is presented in Figures 9 and 10, while the calculated is shown in Figure 11. It can be seen that the and ′′ slightly decreased with the frequency [42][43][44]. In addition, the ′′ had a similar pattern for all composites, which is attributed to the calibration consistent with the loss factor result presented in [45].…”

“…The variation of ε and ε in the 1-12 GHz range is presented in Figures 9 and 10, while the calculated tanδ is shown in Figure 11. It can be seen that the ε and ε slightly decreased with the frequency [42][43][44].…”

Micromechanical Modeling for Tensile Properties of Wood Plastic Composites: Use of Pruned Waste from Pecan Orchards as Sustainable Material for Reinforcement of Thermoplastic Composite

“…Within the development of WPCs, the analysis of wood degradation in the polymer matrix has been one focus of attention [ 22 ]. Understanding the other properties of WPCs is important since applications of the new developed material may be suitable for new applications where it is necessary to evaluate electrical or physical properties [ 23 ].…”

“…No study has been published that used pecan tree pruning flour as reinforcement in polyethylene. Some studies have reported on composites using pecan shells [ 8 , 12 , 14 , 22 , 23 , 29 , 30 ], although with different responses. In these studies, the composites were coupled with different types of coupling agents depending on the matrix type, most of which were polyolefin and polylactic acid.…”

Dielectric Properties of Cellulose and Nanocellulose-Based Materials

“…Based on these advantages, cellulose-based dielectric materials have aroused more and more many attentions. To use bio-based composites in electrical engineering, it is essential to study their behavior in electric fields of various frequencies and at different temperatures (Elloumi et al 2021).…”