The dilute DMF solutions of PLVPs are colorless, and blue emission can be observed when irradiated under 365 nm UV light from a handheld UV lamp (Figures and). Also, the solid powders of PLVPs exhibit bright blue emission under UV illumination at ambient temperature (Figures and). To confirm the observed PL is not caused by any impurity, PLVPs and the corresponding homopolymers, i.e., PMLA and poly(2-vinylpyridine) (P2VP) prepared by FRP with AIBN as initiator were examined. As shown in Figure , both PMLA and P2VP show very weak PL in solution, which is in agreement with the previous reports. Next, to verify that the observed PL of PLVP is not due to any byproducts generated during polymerization, PMLA homopolymer was dissolved in 1,4-dioxane (DOX) and heated with 2VP monomer at the temperature used for polymerization (75 °C) overnight (termed as PMLA@2VP).