Thermal properties and degradation kinetics of epoxy-γ-alumina and epoxy-zinc oxide light weight composites

Abstract

<jats:p>Lightweight composite materials are the gold standard in aeronautical and aerospace applications due to their strength and low mass. To carry higher payloads and decrease launching costs, nanosatellites lightweight. Additionally, nanosatellites must also resist high thermal radiation loads while working in orbit. Polymer-based composite materials maintain low mass and added reinforcing ceramic fillers contributes to increasing radiation resistance, thus producing composites that meet both requirements. In this work, the effects of γ-alumina (Al2O3) and zinc oxide (ZnO) micro- and nanoparticles on the thermal properties and degradation kinetics of epoxy-based composites were investigated. The effective thermal conductivity improved up to 17.8 % for epoxy/γ-Al2O3 and 27.4 % for epoxy/ZnO. The effective thermal diffusivity values show a monotonic decreasing behavior as a function of the particle concentration for the epoxy/γ-Al2O3 composites; for the epoxy/ZnO composites, no correlation on the effective thermal diffusivity values with the ZnO-content was observed. Both oxide-based ceramic fillers increase the thermal stability of epoxy up to 250 °C; however, γ-Al2O3 decreased the maxima decomposition temperature of the epoxy matrix by 6°C. Zinc oxide did not affect the maxima decomposition temperature but decreased the activation energy of epoxy by ~ 45 %. These results provide a feasible manufacturing method for epoxy-based composite materials (i.e. nanosatellites) where efficient heat transfer, heat resistance, and low mass are required.</jats:p>

Constructing magnetic/dielectric dual loss and phonon/electron thermal carriers γ-Al2O3-based yolk–shell microspheres to collaboratively advance microwave absorption and heat conduction

“…It can thus be suggested that compared to other morphologies, such as particles, microspheres, and foams, the yolk–shell structure assembled from nanosheets has a decided advantage in thermally conductive fillers. 18,20,37–50…”

“…It can thus be suggested that compared to other morphologies, such as particles, microspheres, and foams, the yolk-shell structure assembled from nanosheets has a decided advantage in thermally conductive fillers. 18,20,[37][38][39][40][41][42][43][44][45][46][47][48][49][50] By contrast, g-Al 2 O 3 @C YSMSs have a slightly lower HC of 2.06 W m À1 K À1 (2.4% decrease), which is mainly caused by the phonon scattering at the interface between g-Al 2 O 3 and amorphous carbon, together with the intrinsic low heat/electrical conductance of amorphous carbon with low graphitization (Fig. 7c1).…”

Thermal Numerical Analysis of the Primary Composite Structure of a CubeSat

“…However, this effect is outside of the scope of the present investigation and is therefore not quantified. In order to characterize the thermal properties of the composite material, thermogravimetric (TGA) and transient thermal response analysis were performed and the thermal conductivity, diffusivity and heat capacity were calculated [27]. In Table 2, the thermal properties of the epoxy resin/ZnO nanoparticles and the carbon fibre are shown, the properties of the carbon fibre were taken from Reference [29].…”

“…During the first stage of the project it was found that the addition of nanoparticles increase the resistance to UV radiation with respect to the original composite material [24], this effect has been found for different composite and coatings materials [25,26]. Also, the characterization of this composite demonstrated that the presence of the Zinc Oxide nanoparticles (ZnO) into the polymeric matrix slightly improve its thermal properties [27].…”

Characterization of Epoxy-Nanoparticle Composites Exposed to Gamma &amp; UV Radiation for Aerospace Applications

“…Recently, ZnO treatment has been added to epoxy systems, and the stiffness of the composite undergoes a notable 20% increment [11]. Thermal degradation results show that introducing small percentages of ZnO do not alter the thermal degradation of the epoxy resin as well as the thermal properties are briefly improved [12,13]. These reasons push ZnO to be an alternative filler for the facility of synthetizing, processing an integration on thermoset based composites.…”