In this chapter, integrating melt-blown (MB) Polypropylene (PP) fiber mat interleaves into single-polymer composites (SPCs) was demonstrated. SPCs were created by film-stacking using PP film as a matrix, a PP woven fabric as primary reinforcement, and the MB PP fiber mats as an interleaving veil. MB PP fiber mat interleaving improved the SPC’s tensile modulus and interlaminar shear strength by up to 46% and 17%, respectively. The perforation energy of the laminae at impact was also increased by 14% with the PP fiber mat interleaving. Differential scanning calorimetry (DSC) tests showed that MB fibers acted as a nucleating agent in the matrix, resulting in improved crystallinity. Dynamic mechanical analysis (DMA) was conducted, and master curves were constructed based on the time–temperature superposition principle. The storage modulus significantly increased while the tanδ decreased. MB PP fibers created a net-like structure between reinforcing woven and matrix, enhancing interfacial performance. The interleaving concept can promote SPCs utilization in respective engineering applications where high toughness and impact resistance are required.