The development of durable antiviral coatings is critical for protective materials and biomedical applications. Here, we report a catalyst-free strategy to covalently attach an azidoformate-end-functionalized quaternary ammonium oligomer (AF-OAETC) onto polypropylene nonwoven (PNW) substrates via noncatalytic C-H insertion. AF-OAETC was synthesized using an azidoformate-containing azo type radical initiator to polymerize the cationic monomer AETC. Surface analyses confirmed the stable covalent attachment of AF-OAETC to PNW, as evidenced by the retention of the polymer layer after three consecutive washing cycles. AF-OAETC-coated PNW exhibited enhanced hydrophilicity and distinct morphological changes compared to controls. Virucidal assays demonstrated potent antiviral activity, with AF-OAETC-coated PNW achieving a 99.99% reduction in infectious viral particles. In contrast, noncovalently coated controls retained negligible activity. This study established a simple and robust catalyst-free approach for immobilizing antiviral polymers on polymeric nonwoven substrates, as demonstrated using PNW. The resulting materials displayed stability and virucidal efficacy, offering a promising route toward protective textiles and biomedical devices.