High-Performance Properties of an Aerospace Epoxy Resin Loaded with Carbon Nanofibers and Glycidyl Polyhedral Oligomeric Silsesquioxane

Abstract

This paper proposes a new multifunctional flame retardant carbon nanofiber/glycidyl polyhedral oligomeric silsesquioxane (GPOSS) epoxy formulation specially designed for lightweight composite materials capable of fulfilling the ever-changing demands of the future aerospace industry. The multifunctional resin was designed to satisfy structural and functional requirements. In particular, this paper explores the advantages deriving from the combined use of GPOSS and CNFs (short carbon nanofibers) to obtain multifunctional resins. The multifunctional material was prepared by incorporating in the epoxy matrix heat-treated carbon nanofibers (CNFs) at the percentage of 0.5 wt% and GPOSS compound at 5 wt% in order to increase the mechanical performance, electrical conductivity, thermal stability and flame resistance property of the resulting nanocomposite. Dynamic mechanical analysis (DMA) shows that the values of the Storage Modulus (S.M.) of the resin alone and the resin containing solubilized GPOSS nanocages are almost similar in a wide range of temperatures (from 30 °C to 165 °C). The presence of CNFs, in the percentage of 0.5 wt%, determines an enhancement in the S.M. of 700 MPa from −30 °C to 180 °C with respect to the resin matrix and the resin/GPOSS systems. Hence, a value higher than 2700 MPa is detected from 30 °C to 110 °C. Furthermore, the electrical conductivity of the sample containing both GPOSS and CNFs reaches the value of 1.35 × 10−1 S/m, which is a very satisfying value to contrast the electrical insulating property of the epoxy systems. For the first time, TUNA tests have been performed on the formulation where the advantages of GPOSS and CNFs are combined. TUNA investigation highlights an electrically conductive network well distributed in the sample. The ignition time of the multifunctional nanocomposite is higher than that of the sample containing GPOSS alone of about 35%.

A Comprehensive Review on the Thermal Stability Assessment of Polymers and Composites for Aeronautics and Space Applications

“…Owing to numerous advantages surpassing conventional materials like metals or ceramics [15,[100][101][102][103][104][105][106][107][108], epoxy composites are increasingly playing a primary role in the aeronautical and aerospace sectors. Some of their pivotal benefits include [109][110][111][112]:…”

“…Owing to numerous advantages surpassing conventional materials like metals or ceramics [ 15 , 100 , 101 , 102 , 103 , 104 , 105 , 106 , 107 , 108 ], epoxy composites are increasingly playing a primary role in the aeronautical and aerospace sectors. Some of their pivotal benefits include [ 109 , 110 , 111 , 112 ]: Exceptional strength-to-weight ratio, giving them a fusion of robustness and lightness, thus minimizing the overall weight and fuel consumption of aircrafts.…”

Multifunctional Properties of Polyhedral Oligomeric Silsesquioxanes (POSS)-Based Epoxy Nanocomposites

“…In this context, the POSS cages to be incorporated into polymeric matrices are becoming increasingly important. They represent an innovative class of materials with a unique nanometric structure [ 46 , 47 , 48 ] and awesome mechanical and thermal properties that make them ideal reinforcing reagents [ 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 ].…”

Use of Bio-Epoxies and Their Effect on the Performance of Polymer Composites: A Critical Review

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