Preparation And Properties Of Phthalide Leuco Luminous Fibers

The rare earth luminous fiber is a kind of functional fiber which is prepared from rare earth long afterglow luminescent materials and fiber forming polymer.Rare earth luminous fiber is one of energy storage material which is able to store the luminous energy after excited by ultraviolet or visible light and keep shining in darkness.Because of its high energy storage,long afterglow and non-radioactive,the rare earth luminous fiber has been applied in various functional clothing and textiles.Phthalide leuco is the leuco dye with phthalide structure.It shows different absorptivity in visible light band because it can open or close lactonic ring to change conjugated degrees.This work found that phthalide leuco could influence the luminescence of rare earth luminescent materials to change the luminous property of luminous fiber while phthalide leuco changed its molecular structure.This work analyzed how phthalide leuco influenced the emission spectra of luminous fibers,and summarized the rules that phthalide leuco converted the luminescent color of luminous fibers.Phthalide leuco luminous fibers were prepared.It is able to change the luminescent property with temperature.It enriches the types of luminous fiber and expands the application of luminous fiber in the thermal sensing field.The main research work and results are shown as following:?1?Sr₂ZnSi₂O₇:Eu²⁺,Dy³⁺,SrAl₂O₄:Eu²⁺,Dy³⁺ and Y₂O₂S:Eu³⁺,Mg²⁺,Ti⁴⁺ were prepared by high temperature solid method.The optical properties of luminous fibers were characterized by fluorescence spectrometer.The emission spectra of ternary blending luminous fibers were studied.It is found that the luminous fibers with polychromatic color emission can be prepared by blending various rare earth luminescent materials into fiber forming polymer.The luminous fibers with white light emission can be prepared by deploying the proportion of rare earth luminescent materials.?2?Several phthalide leuco luminous fibers were prepared by adding different phthalide leuco pigments into luminous fibers.It is found that phthalide leuco pigments does not destroy the phase structures of rare earth luminescent materials.Each component shows good independence in the fiber so that ensure the luminescence property of rare earth luminescent materials.Moreover,the feasibility of wet spinning process is verified.It provided technological support for analyzing the effects of phthalide leuco dye on luminous fiber emission spectra and luminescent color.?3?The effects of phthalide leuco on the emission spectra of luminous fibers were studied.It can be summarized that when the emission spectra of the rare earth luminescent materials overlap with the absorption spectra of phthalide leuco dye,the light from the rare earth luminescent materials is shielded in fiber by phthalide leuco pigment.The light energy from the rare earth luminescent materials can be released when the phthalide leuco dye change to Lactone structure.It can be seen that when the phthalide leuco dye transforms the structure in the fiber,the emission spectrum of the luminous fiber can be converted.?4?From the visible light absorptivity of phthalide leuco pigment and emission spectra of luminous fibers,it can be found that the phthalide leuco dye which has only part of the absorptive capacity in visible band can selectively absorb the luminescence from rare earth luminescent materials.In Quinone structure,the phthalide leuco can absorb the light from rare earth luminescent materials and release other light energy.All light energy can be released when phthalide leuco transforms to lactone structure,so as to achieve the conversion of luminescent color.The conversion of phthalide leuco luminous fibers can be seen by naked eyes indicating that it has practical application value.?5?The stabilities of phthalide leuco luminous fibers were studied.The results show that the phthalide leuco luminous fibers can keep stabilization below 200 ?.Phthalide leuco luminous fibers have heat resistance,acid and alkali resistance,light resistance and good water resistance.The fibers can keep stability below 200 ?.Using ultraviolet to stimulate phthalide leuco luminous fibers to store energy will not destroy their luminescent conversion property.It will reduce the luminous intensity of the fibers to keep phthalide leuco luminous fibers in acid or alkali,but it will not affect its light conversion property.Phthalide leuco luminous fibers are stability in water.Keep fibers in water for long time will not destroy their light-color conversion property.