*Article* **A Facile Synthesis Route of Hybrid Polyurea-Polyurethane-MWCNTs Nanocomposite Coatings for Ballistic Protection and Experimental Testing in Dynamic Regime**

**Gabriela Toader <sup>1</sup> , Aurel Diacon 2,\* , Edina Rusen 2, Florica Rizea 2, Mircea Teodorescu <sup>2</sup> , Paul O. Stanescu 2, Celina Damian <sup>2</sup> , Adrian Rotariu 1, Eugen Trana 1, Florina Bucur <sup>1</sup> and Raluca Ginghina <sup>3</sup>**


**Abstract:** This study describes a simple, practical, inexpensive, improved, and efficient novel method for obtaining polyurea-polyurethane-multiwall carbon nanotubes (MWCNTs) nanocomposites with enhanced mechanical properties, and their experimental testing in a dynamic regime. SEM and micro-CT investigations validated the homogeneity of the nanocomposite films and uniform dispersion of the nanofiller inside the polymeric matrix. The experimental measurements (TGA, DSC, DMA, and tensile tests) revealed improved thermal and mechanical properties of these new materials. To demonstrate that these nanocomposites are suitable for ballistic protection, impact tests were performed on aluminum plates coated with the polyurea-polyurethane MWCNTs nanocomposites, using a Hopkinson bar set-up. The experimental testing in the dynamic regime of the polyureapolyurethane-coated aluminum plates confirmed that the nanocomposite layers allow the metal plate to maintain its integrity at a maximum force value that is almost 200% higher than for the uncoated metallic specimens.

**Keywords:** polyurea-polyurethane; nanocomposite; ballistic protection; coatings; mechanical properties; multiwall carbon nanotubes (MWCNTs); Hopkinson bar
