Synthesis And Characterization Of Light Emitting Polymers Containing 1,3,5-triazine And Chalcone Groups

A series of symmetrically tri-substituted triazines 3-10 were synthesized by solid grinding with yield up to 85%. Asymmetrically substituted triazines 11, 12 and 14 were prepared by two step reaction in acetone/H₂O with the total yield over 50%. The structures of these triazines derivatives were characterized by melting point, GPC, FT-IR, MS, ¹H-NMR, ¹³C-NMR and elemental analysis.A series of chalcones 15-18 and triazines 19, 20 were synthesized under ethanol/H₂O/base condition. Their structures were confirmed by melting point, GPC, FT-IR.Arylethynylenes 25-29, 36 with -C(CH₃)₂OH group were prepared by Pd/Cu catalysed C-C cross-coupling reaction. The de-acetone products 30-33 were obtained in toluene at 120℃ under reflux. The structures were characterized by melting point, GPC and ¹H-NMR.Poly(aryleneethynylene)s containing 1,3,5-triazine (P1, P3 and P4) were prepared by the polycondensation of diethynylbenzene derivatives with diiodoaromatic compounds using Sonogashira coupling reaction. Their structures were characrerized by model molecules and GPC, FT-IR, MS, ¹H-NMR, and ¹³C-NMR. The molecular weight of these polymer increased with the increasing of reaction time, temperature and catalyst. Eexcess of bisalkyne increased polymer molecular weight, because of the oxygenated coupling of alkyne. Molecular weight of polymer also increased by introducing long alkoxy groups at side chain. In UV-Vis spectra, the λ_max of PI, P3 and P4 polymers were at 325nm, 372nm and 372nm respectively. Comparing with spectra of BPB moiety, P3 and P4 polymers exhibited red shift ⁴7nm. Fluorescence analysis indicated that these polymerswere blue-green light-emitting materials.A new conjugated polymer P5 with chalcone moiety in the main chain was synthesized by Sonogashira coupling reaction. The structure was characterized by model molecule and GPC, FT-IR, MS, 'H-NMR, and 13C-NMR. The polymer was well solubile in common organic solvents and had Mw/Mn of 12706/6870, as measured by GPC using PS as standard. The polymer melted at 55-65 "C and lost 20% weight at 400°C. X msa of P5 was at 420nm, and would blue-shifted by increasing solvent polarity. The polymer exhibited green fluorescence emission.