Preparation Of Aminostyrylpyridinium Salts And The Study Of Fluorescent Fiber

Among various organic NLO materials,aminostyrylpyridinium salts (stilbene-type dyes,hemicyamine dyes),possessing donor group on one end and acceptor group on the other end,had found some successful application in science and technology.That their derivatives also are promising materials for the photo-induced second-order optical effects,which allows expecting that they may be used as multi-functional materials,possessing both linear and non-linear fluorescence. However,to the best of the authors' knowledge,there is no report about the application of aminostyrylpyridinium salt to fluorescent fiber(fabric).In this article, we present eleven aminostyrylpyridinium salts,with an electron donor(disubstituted amino) and an aromatic acceptor moiety joined by a flexible bond.The goal is to prepare fluorescent fiber using these 11 aminostyrylpyridinium salts.Main Conclusions contained four parts as follows.1).Firstly,eleven aminostyrylpyridinium salts have been synthesized and their structures have been confirmed.Then their optical properties in solution and aggregation were investigated.Results showed that OH-in donor groups had bigger effect on linear optical properties of dyes than substituted amine in acceptor groups, and the anion had influence on both solvability and optical properties.With the increase of the solvent polarity parameter,the absorption spectra were blue-shifted,the fluorescence spectra were red-shifted and there had an obvious decrease in fluorescence intensity and fluorescence quantum yield.Six dyes in DMF possess good TPA behaviors and the non-linear optical experimental results of DHEASPT-C₈ by the Z-scan technique at 532 nm showed that the NLO absorption coefficientβwas 3.09×10^-11 m/W and the third-order NLO coefficient x⁽³⁾ was 4.78×10^-12 esu.2) In the facile reacting condition,two kind oligomers,polyimide and polysiloxane, attached with aminostyrylpyridinium salt group were synthesized successfully.And they all had obvious fluorescent properties.As polyimide oligomer is concerned,there were some blue shifts of characteristic peaks that corresponded to hemicyanine dyes in the UV spectra and fluorescence spectra.But there is no obvious change in polysiloxane oligomer.3) Acrylic fabrics and silk fabrics were dyed with several water-soluble aminostyrylpyridinium salts following conventional dyeing procedure of cationic dyes. The light colorfastness of dyed fabrics was evaluated according to the AATCC TM 16-2003 standard method,and the results showed that the colorfastness of all three samples was only grade 2.The reflectance of the dyed fabrics exceeded 100%in the emission range and four aminostyrylpyridinium salts had the similar ability to produce fluorescence as the Yellow X-10GFF.The adsorption of aminostyrylpyridinium salts onto acrylic fibers was found to follow a Langmuir mechanism,and the dye uptake and sorption rate increased with increasing alkyl chain length of the dye molecule.4) A series fluorescent mats had been made through electrospinning process by adding aminostyrylpyridinium salts to fibre-forming polymers.The diameters of fibers selected from the electrospun mats were in nanometer scopes.To improve the stability of electrospun mats,inorganic phosphors,Eu₂WO₆ and NaCaPO₄:Eu²⁺,were synthesized and the optical properties of both inorganic phosphors and electrospun mats containing Eu₂WO₆ had also been discussed.