Title: Enhancing Ballistic Armor Performance Using Nanomaterial-Modified Epoxy and Polyurethane

Authors: Travis Murphy, Eltahry Elghandour, Amro El Badawy

DOI:

Abstract: Hybrid armor systems use compliant polymer layers to spread impact loads and protect rigid backing structures. This study examined how graphene nanoplatelets, carboxyl functionalized carbon nanotubes, nanoclay, titanium oxide, and silicon oxide affect the mechanical and ballistic performance of epoxy and polyurethane matrices. Epoxy was used as a reference structural matrix, while polyurethane was selected as an energy absorbing buffer material based on toughness focused materials selection. Nanomaterials were added at around .2 wt% loadings using ultrasonic dispersion and cast into test specimens using additively manufactured molds. Mechanical behavior was evaluated using tensile testing for epoxy and polyurethane samples. Ballistic performance was assessed using hybrid armor assemblies with a Kevlar strike face, polyurethane compliant buffer, and a composite back plate impacted by 9 mm full metal jacket and hollow point projectiles. Results showed that nanomaterial additions significantly increased the tensile strength and load carrying capacity of polyurethane while maintaining substantial strain to failure. In contrast, nanomaterial reinforcement of epoxy was limited by dispersion related defects and reduced fracture performance. These findings demonstrate that matrix selection controls nanocomposite effectiveness and supports the use of nanomodified polyurethane as an energy absorbing layer in lightweight hybrid ballistic armor systems.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 94

Pages: 13

Price: $26.00