Synthesis of water‐soluble perylenediimide‐functionalized polymer through esterification with poly(vinyl alcohol)

A new material has been prepared by covalent attachment of a perylene derivative, N ‐(carboxyphenyl)‐ N ′‐(8‐pentadecyl)perylene‐3,4:9,10‐bis(dicarboximide) (PDI‐COOH), to poly(vinyl alcohol) (PVA) by esterification. The perylenediimide (PDI)‐modified PVA polymers are soluble in water and dimethylsulfoxide (DMSO). This solubility is conferred to the insoluble perylene derivative by the water‐soluble polymer. The materials have been characterized by hydrogen‐nuclear magnetic resonance, Fourier transform infrared spectra, X‐ray diffraction, and X‐ray photoelectron spectroscopy confirming the covalent attachment of the PDI to the polymer chains. The significant changes in the crystalline parameters and the thermal stability observed for the polymer after the esterification also confirm the covalent linkage with PDI. In addition, the PDI‐modified PVA shows good fluorescence both in solution (quantum yield ∼0.2–0.25) and in solid suggesting that the PDI retains largely its photochemical and photophysical properties after immobilization.