Title: Nano-Reinforced Potting Paste Compounds with Improved Mechanical Properties for Primary Structural Applications

Authors: Davood Askari, Amrith Pulipaka

DOI:

Abstract: Potting compounds play a critical role in aerospace sandwich composite structures, particularly for load transfer, void filling, sealing, and bonded insert applications. Enhancing their mechanical and adhesive performance without significant weight penalties remains a challenge. This study investigates the effects of multi-walled carbon nanotube (MWCNT) reinforcement on the compressive, adhesive, surface, and chemical properties of a commercial polyester-based potting compound. CNTs were incorporated at 0, 0.05, 0.10, 0.15, and 0.20 wt.% using a twostage dispersion process involving hand pre-mixing and three-roll milling. Mechanical performance was evaluated through compressive strength and single-lap shear testing, while surface wettability and chemical stability were assessed using water contact angle measurements and Fourier transform infrared spectroscopy (FTIR). Results demonstrate that low CNT concentrations (≤0.10 wt.%) considerably improve compressive strength and may negatively impact lap shear performance, while higher concentrations lead to increased brittleness and reduced strain-to-failure. FTIR analysis confirmed no chemical degradation of the polymer matrix and contact angle measurements indicated persistent hydrophilic behavior. These findings highlight the importance of optimized CNT content and dispersion for aerospace-grade potting compounds for primary structural applications.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 72

Pages: 18

Price: $36.00