In this study, the (1‐benzofurane‐2‐yl)‐3‐oxo‐prop‐1‐en‐1‐yl]‐2‐methoxyphenyl 2‐methyl acrylate monomer were synthesized from the acylation reaction of this compound with methacryloyl chloride that commercially purchased. Free radicalic or atom transfer radical polymerization methods were used for preparation of copolymers. FT‐IR, 1H and 13C‐NMR techniques were used for structure characterization of polymers. The thermal behaviors of polymers were relatively investigated by DSC and TGA, and the results were compared with each other. The dielectric behaviors of polymers were investigated as a function of temperature and frequency. The results obtained were associated with their the structures. The spectroscopic properties of the polymers were investigated by UV‐Vis and fluorescence spectroscopies. Effects of the solvent polarity on emission measurement were investigated with fluorescence spectroscopy. Under cover of dimerization property of chalcone, the chalcone ended polymer was photodimerizatied.