Preparation And Properties Of Fluorescent Dye/SiO₂Hybrid Nano-materials

The fluorescent dye/SiO2hybrid material is a novel composite materialcombining the advantage of both organic dyes and inorganic materials. Thepolymer fluorescent dye contains both the coloring characteristics of thefluorescence dye molecules and the high stability and low toxicitycharacteristics of polymer materials, the polymer fluorescent dye hascomprehensive applications in staining, laser recording and opticalcommunication.The fluorescent dye/SiO2hybrid materials were preparedusing fluorescent dye and researched their properties.(1) A series of novel polymeric fluorescent dye was prepared using3-(2-benzimidazolyl)-7-(diethylamino)-coumarin (Disperse yellow8GFF) andpolyethylene glycol (PEG) as raw materials. Carboxyl-terminated8GFFcondensate intermediate was prepared firstly by condensation of8GFF andpyromellitic dianhydride (PMDA); the polymeric fluorescent dye wassynthesized by reacting PEG with the condensate intermediate. The polymericfluorescent dye was characterized by FT-IR, UV-vis, PL and DSC. The resultsof FT-IR spectra showed that the polymeric fluorescent dye was ofhydroxy-terminated polyether structure. UV-vis spectra and PL spectraindicated that the structure of the coumarin in the polymeric fluorescent dyedid’t change. DSC curves and UV radiation testing suggested that thepolymeric fluorescent dye had higher melt point and better UV-resistant thanthat of8GFF. With the increase of the molecular weight of PEG, the PLintensity of the polymeric fluorescent dye decreased gradually; and melt pointof the polymeric fluorescent dye was elevated and UV-resistance of thepolymeric fluorescent dye was modified correspondingly.(2) The disperse yellow8GFF/polyurethane (8GFF-PU) polymerfluorescent dye was prepared with8GFF-PMDA-PEG600polymer fluorescentdye,4,4’-diphenylmethane diisocyanate (MDI) and PEG600; the PU/SiO2hybrid fluorescent nanospheres were prepared by grafted8GFF-PU polymerfluorescence dye onto the surface of single-dispersed SiO2nanospheres.Hybrid fluorescent nanospheres were characterized by FT-IR, UV-vis, TG, PLand TEM. The results showed that the hybrid fluorescent nanospheres still maintained good fluorescence properties and thermal stability.(3) Using AIBN as initiator, styrene-maleic anhydride copolymer(SMA)was synthesized via solution-precipitation polymerization, then it was reactedwith fluorescent dye8GFF, and the polymeric dye of8GFF side linked SMAcopolymer was prepared. The polymeric dye was analysized and characterizedwith Fourier transformed infrared spectroscopy(FTIR), differential scanningcalorimeters(DSC), and photoluminescence(PL). FTIR and UV-vis spectrasuggested that8GFF side linked SMA copolymer had been prepared. PLspectra showed that the polymeric dye has similar luminescence performance.DSC curves showed that the polymeric dye had superior heat-resistance,implying its widely use in dying of many polymer materials, such asengineering plastics.(4) Fluorescent hybrid nanospheres of SiO2/Rhodamine B were prepared.Firstly,3-glycidyloxypropyl trimethoxysilane (KH560) reacted withRhodamine B in water-in-oil microemulsion, and then they reacted with TEOSin the microemulsion by sol-gel in-situ. The hybrid nanospheres werecharacterized by FT-IR, UV-vis, TG, PL and TEM. The results showed thatRhodamine B was linked to SiO2via chemical bond; the diameter of hybridnanospheres was about200nm; the nanospheres showed better heat resistanceand UV light resistance than Rhodamine B; the PL intensity of the hybridnanospheres was about4times of Rhodamine B.