Syntheses and photoluminescence properties of UV photocrosslinkable polyesters based on fluorene

Chemo-enzymatic Synthesis, Derivatizations, and Polymerizations of Renewable Phenolic Monomers Derived from Ferulic Acid and Biobased Polyols: An Access to Sustainable Copolyesters, Poly(ester-urethane)s, and Poly(ester-alkenamer)s

“…Other homo-and copolyesters of natural p-hydroxycinnamic acids showing remarkable liquid-crystal (28)(29)(30)(31)(32)(33)(34)(35), biodegradability (36,37) or biocompatibility (30) properties were also reported. However, they are often hard to process because of a too high melting temperature (T m ).…”

Intensity enhancement of photoluminescent polyesters by photocrosslinking

“…). The intensity of the olefinic bond, −C = C−, at 1618 cm −1 was observed to decrease due to the opening of the unsaturated − C = C− bond to form the cyclobutane ring after UV irradiation . Furthermore, the shift of the C = O band to higher frequency, 1649 to 1657 cm −1 , indicated the change from the fully conjugated − C = C−(CO) − C = C− group into the partially conjugated − C − C−(CO) − C = C− group.…”

Insoluble porous conjugated polymer films via phase separation and photo‐crosslinking for the trace detection of 2,4‐dinitrotoluene

“…The normalized PL emission intensities at 500–550 nm decrease slightly as the irradiation time increases. The green emission at 500–550 nm decreases partly due to the suppression of chain aggregation, which may stem from the crosslinked structure which could isolate conjugated polymeric chains in the solid film state . In addition, the fluorescence quantum efficiency ( Φ PL ) of the crosslinked PFC1 ( Φ PL = 0.47) after exposure to UV light for 150 s increases by 6% compared with the non‐crosslinked polymer PFC1 ( Φ PL = 0.41).…”

“…The green emission at 500-550 nm decreases partly due to the suppression of chain aggregation, which may stem from the crosslinked structure which could isolate conjugated polymeric chains in the solid film state. 27 In addition, the fluorescence quantum efficiency ( PL ) of the crosslinked PFC1 ( PL = 0.47) after exposure to UV light for 150 s increases by 6% compared with the non-crosslinked polymer PFC1 ( PL = 0.41). These results also reveal that the crosslinked network formed by photodimerization of coumarin groups imparts a higher fluorescence quantum efficiency, and to a certain extent suppress chain aggregation in the film.…”