Biobased post-functionalized networks were designed by photoinduced cationic reaction using a biheterofunctional eugenol derivative. The originality of this study is to mobilize the carbon double bond of this compound which did not react during the formation of the networks so as to graft molecules of interest to the surface of the materials (here an antibacterial agent). The photoactivated thiol–ene reaction was chosen for the post-functionalization since this chemical route is nowadays considered a green process and leads to fast kinetics and high conversions. Different networks were prepared by varying the proportion of carbon double bond and consequently the proportion of antibacterial compound grafted into the resulting material. The thermo-mechanical performances and the biological activity were strongly investigated before and after the post-functionalization process.