Epoxy–nanocomposites with ceramic reinforcement for electrical insulation

Abstract

Ceramic nanoparticles, that is, SiO 2 , TiO 2 , and Al 2 O 3 nanoparticles, with increasingly high thermal conductivity (k), represent good candidates for improving the thermophysical properties of epoxy resins. In this study, the influence of filler addition on the thermal, mechanical, and dielectric properties were investigated by means of differential scanning calorimetry, dynamic mechanical analysis, and dielectric spectroscopy to measure k, storage and loss moduli, dielectric permittivity, and volume resistivity. Moreover, morphological investigations by scanning electron microscopy were performed to confirm the particle dispersion into the epoxy matrix. The results show that both the elastic modulus and glass-transition temperature increased with particle content. An enhancement of k was also observed at high filler contents because of the formation of heat conductive pathways within the matrix. The nanocomposites' relative permittivity at 50 Hz was lower, whereas the dielectric loss was slightly higher compared with that of the neat epoxy matrix. A decrease in the relative permittivity with increasing frequency, both for the unfilled epoxy resin and epoxy-nanocomposites, was observed.

Relationship between crosslinking structure and low dielectric constant of hydrophobic epoxies based on substituted biphenyl mesogenic units

“…Yalan Wu 12 reported that the dielectric constant and dielectric loss values decreased with the increasing addition of NH 2 -POSS into original epoxy resin. Amendola, E 13 and S. S. Vaisakh 14 found the dielectric constant could be decreased with introduction of ceramic nano llers. Jiao, Jian 2 added novel organic-inorganic particles (denoted POSS-MPS) into the epoxy resin and the POSS-MPS/EP nanocomposites containing 5 wt% of POSS-MPS showed a lower dielectric constant (D k ¼ 3.66) and loss factor (D f ¼ 0.017) in comparison to pristine EP with the value of 4.03 and 0.031.…”

Effect of amounts and types of silicon nitride on thermal conductivity of Si₃N₄/epoxy resin composite

“…2) It is known that the thermal conductivity of resins can be enhanced by adding ceramic fillers, and many reports have been published with the aim of enhancing the thermal conductivity of resins by adding of alumina (Al 2 O 3 ), 3) carbon fibers, 4) nanotubes, 5) silicon carbide, 6) and nitride fillers.…”

MAX phase ternary carbide derived 2-D ceramic nanostructures [CDCN] as chemically interactive functional fillers for damage tolerant epoxy polymer nanocomposites

“…It is also emerging as a dielectric material to substitute porcelain and glass insulators. 1,2 A major drawback of the epoxy polymer is its low thermal dissipation property due to poor thermal conductivity (l ¼ 0.2 W mK À1 ), high thermal expansion coefficient (a ¼ 66.5 mm m À1 C À1 ) together with weak thermal shock resistance and profusely poor crack propagation resistance that oen leads to catastrophic mechanical failures. These undesired thermo-mechanical properties ultimately restrict the use of this economically benign glassy polymer for engineering applications.…”