Synthesis of Methacrylic Monomers Bearing Stilbenoid Chromophore and Their Free-Radical Polymerization To Give Luminescent Polymers

In the present paper, we report the synthesis of two new methacrylates and their efficient free-radical polymerization to luminescent polymers. They dissolved in common organic solvents such as THF, dichloromethane, chloroform, and toluene and had relatively low T g values (52−87 °C). In addition, they showed a satisfactory thermal stability, being stable up to 278−325 °C in N2 or air and afforded anaerobic char yields of 47−73% at 800 °C. The optical properties of polymers were investigated both in solution and in thin film, utilizing the UV−vis, the PL excitation, and PL spectroscopy. The polymers behaved as violet-blue and violet-greenish emitting materials. Their PL spectra displayed maxima in solution at 397 or 457 nm and in thin film at 413 or 507 nm. The low-temperature PL spectra in solution were red-shifted by 7−15 nm in comparison with the respective room-temperature spectra, and for one polymer, they displayed a new peak due to the reduced rotation. The PL quantum yields in solution were up to 0.30. The influence of the polymer concentration in solution as well as of the solvent polarity on the PL curves was investigated. It was shown that the PL curves were progressively red-shifted with increasing the solvent polarity.