Polytetrafluorethylene, PTFE, films were activated and modified via gamma-rays to graft, in two steps, first methyl methacrylate, MMA, and subsequently N-vinylimidazole, NVI. The modified materials with a more reactive surface, PTFE-g-MMA and (PTFE-g-MMA)-g-NVI, were characterized spectroscopically and thermally; also, the behavior of the films was recorded through all the grafting process with experiments including swelling and contact angle, suggesting changes in the hydrophilic/hydrophobic features. The change in reactivity due to the NVI chains was confirmed by the easy reaction of the modified films with AgNO3, resulting in the metal immobilization with the consequent formation of nanoparticles and aggregates. Mechanical properties and SEM-EDS and XPS spectra were also investigated. Finally, Ag-loaded (PTFE-g-MMA)-g-NVI films were challenged against Gram-positive and Gram-negative bacteria confirming antimicrobial performance.