Investigation On Preparation And Luminescence Of Tunable Fluorescent Anti-counterfeiting Functional Composite Materials

Ca CO3: RE3+(RE=Eu,Tb,Ce) and Ca CO3:Eu3+, Ce3+ phosphors were synthesized via co-precipitation route assisted by microwave in this article. A series of Ca CO3: RE13+(m)/ Ca CO3: RE23+(1-m)(RE=Eu,Tb,Ce) tunable phosphors were fabricated by physical blending. The phosphors were organic modified by aluminate coupling agent(DL-411-DF). A series of tunable polypropylene plastic were prepared by the phosphors and PP and a series of tunable polylactic acid film were prepared by the phosphors and P LA. The crystall phase, morphology, structure and particle size of phosphor were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM) and laser particle size ana lyzer, respectively. The modified powder were characterized by fourier transform infrared(FT-IR), thermogravimetry(TG) and contact angle meter, respectively. The mechanical properties of polypropylene composites were tested. The results showed that:(1) Ca CO3: RE3+(RE=Eu,Tb,Ce) trichromatic phosphor were synthesized by microwave co-precipitation. Ca CO3:RE13+(m)/Ca CO3:RE23+(1-m)(RE=Eu,Tb,Ce) tunable phosphors were fabricated by physical blending. The emission changed effectively by altering the composition and excitation wavelength of phosphors. The Ca CO3: Eu3+ were organic modified by liquid phase method which aluminate coupling agent(DL-411-DF) as modifying agent. The modified temperature is 80℃, time is 90 min and modifier dosage is 3wt%. The modified particle size was bigger and emission intensity was higher. The excitation and emission peaks did not change.(2) Ca CO3:Eu3+/PP, ACA-Ca CO3:Eu3+/PP, orange powder/PP and green powder/PP composites were prepared by banbury mixer. Both blengding strength and impact strength of the four materials were bigger. But the tensile strength become small. The mechanical properties of ACA-Ca CO3:Eu3+/PP were better than Ca CO3:Eu3+/PP. As the powder adding quantity increased, the fluorescence intensity increases. Synthesizes each kind of properties, the best dosage of Ca CO3:Eu3+ and ACA-Ca CO3:Eu3+ is 5wt%, the best dosage of orange powder and green powder is 3wt%. A variety of fluorescent polypropylene composite materials were prepared by banbury mixer. The emission of ACA-Ca CO3:RE13+(m)/AC A-Ca CO3:RE23+(1-m)/PP and AC A-Ca CO3: m Eu3+,n Ce3+/PP changed effectively by altering the composition and excitation wavelength of phosphors. As a result of the polypropylene composite is colorless in sunlight. So it has highly concealment, this kind of material is expected to be widely used in the field of anti-counterfeiting. The emission of orange powder/PP and green powder/PP changed from orang to green by a ltering the composition. Change the wavelength would have little impact on the material emission color. So the application of such materials in the field of anti-counterfeiting is narrow. Due to its high luminous intensity, they were expected to be used in the identification and other fields.(3) Ca CO3:Eu3+/PLA, ACA-Ca CO3:Eu3+/PLA, orange powder/PLA and green powder/PLA composites were prepared b y volatile film- forming method. As the powder adding quantity increased, the fluorescence intensity increases. A variety of fluorescent polylactic acid composite films were prepared by volatile film- forming method. The emission of ACA-Ca CO3:RE13+(m)/ ACA-Ca CO3: RE23+(1-m)/PLA changed effectively by altering the composition and excitation wavelength of phosphors. As a result of the polylactic acid composite film is colorless in sunlight. So it has highly concealment, this kind of material is expected to be widely used in the field of anti-counterfeiting. However, The emission of orange powder/PLA and green powder/PLA changed from orang to green by altering the composition. C hange the wavelength would have little impact on the material emission color. So the application of such materials in the field of anti-counterfeiting is narrow. Due to its high luminous intensity, they were expected to be used in the identification and other fie lds.In this article, the polypropylene and poly(lactic acid fluorescence function composite material performance is stable, the price is low, suitable for polymer materials, is expected to become a new type of anti-counterfeiting materials, so the research for the application laid a foundation of this kind of material in the field of anti-counterfeiting.