Tunable room-temperature phosphorescence from amorphous polymers based on pyridine-substituted triphenylamine via <?A3B2 pi6?>rational molecular engineering

Room-temperature phosphorescent (RTP) polymers have garnered significant interest due to their broad application prospects. However, achieving efficient and tunable RTP typically requires meticulous molecular design. In this work, a series of polymers incorporating pyridine-substituted triphenylamine chromophore, including the homopolymer P1, copolymer P2, and ionic polymer P3, were designed and synthesized to achieve tunable RTP. Precise regulation of RTP properties was achieved through stepwise structural modification and matrix-assistance. The hydrophobic P1 exhibited no RTP in the polyvinyl alcohol (PVA) matrix due to microphase separation and chromophore aggregation. In contrast, copolymer P2 containing spatially isolated phosphors constructed a three-dimensional hydrogen bond network, thereby simultaneously suppressing the non-radiative decay pathways and enhancing the compatibility with PVA matrix. Consequently, the P2/PVA film displayed an ultralong RTP lifetime of 260.5 ms, which further increased to 612.5 ms following UV photoactivation. Notably, ionic polymer P3 possesses robust ionic bonding, efficient intersystem crossing, and good hydrophilicity, thus exhibiting pure orange/yellow phosphorescence in both solid powder and PVA matrix. Based on the distinct afterglow durations, photoactivated behavior, and color-gradient luminescence of P1-P3, a multidimensional dynamic anti-counterfeiting system was developed. This study provides important guidance for exploring polymeric RTP materials with tailored properties for diverse applications.