Preparation And Performance Characterization Of Optical Fiber Fluorescence Sensing And Optical Fiber Random Laser Materials

Since optical fiber was put forward can be used for information transmission,it has become an essential information materials.Compared with the traditional information transmission medium,the optical fiber transmission has the advantages of light weight,low loss,wide band,high fidelity and strong anti-jamming capability.Therefore,many hot research fields are derived from optical fiber,among which optical fiber fluorescent sensor and optical fiber random lasing have attracted more and more researchers' attention.Combining fluorescence and optical fiber sensor technology to build the optical fiber fluorescent sensor has the advantages of small size,light weight,and can online real-time detection of multicomponent analysis.This paper with the aid of molecular imprinting technology,the preparation of a kind of optical fiber fluorescence sensors with specific recognition ability for D-aspartate(D-Asp).And the sensor performance was characterized and analyzed.In addition,based on the generation mechanism of random lasing,polymer-quartz composite optical fiber was prepared by modifying the surface of ordinary quartz fiber cladding,and its performance is studied.The main research contents are as follows:1.The optical response behaviors of PBI derivatives(PBIs)were studied through literature review and theoretical analysis.The effects of peri-and bay-displacement on the properties of PBI were discussed.Then,the introduction of 2-(dimethylamino)ethylamine to peri position of 1,7-disubstituted perylene bisimide(1,7-PBIs)provide photoinduced electron transfer(PET)type molecules with fluorescent turn-on properties in acid condition.By Ullmann reaction at bay 1,7-position with allyl 4-hydroxybenzoate,reactive monomer(PBIM)was synthesized.Fluorescent response at mixture solution of CH3CN and water show fluorescent turn-on for D-Asp.The responsive mechanism is based on the acid and alkali complex(PBIM/D-Asp)form as pKa-matching,and thus the complex inhibits the effect of PET from tertiary amine to perylene core.Finally,we use triallyl isocyanurate,alkane dithiols and PBIM/D-Asp complexes to form a D-Asp imprinted polymer film at the end of coaxial polymer optical fiber(CYPOF).Compared with sensing performance of the non-molecular imprinted polymer optical fiber sensing material(NIP-CYPOF),the molecular imprinted polymer optical fiber sensing material(MIP-CYPOF)has an advantage as it simplifies the detection strategy,improves the sensitivity,selectivity and recyclability of the POF fluorescence probe.2.Through synthesizing two PBIs molecules:the DPP and DCP,and study these absorption and fluorescence emission spectrum.It's found the near-field scattering enhancement effect exists in DPP solution,and try to apply it in optical fiber random lasing with DPP.Polymer-quartz composite fiber with DPP as dye was prepared by dip-coating and adsorption method,wherein the core was quartz and the cladding was DPP doped PEO.A 532nm laser was used to lateral pump the composite region of the composite fiber.The results showed that with the increase of pump energy,the fluorescence was narrowed but no random lasing was produced.And the random lasing was still not produced after trying various improvement methods.After analyzing the reasons,the weak scattering effect in DPP may not be enough to generate random lasing in the composite fiber.Therefore,we transferred the research target to the common laser dye PM597,and explored its basic optical properties such as absorption and emission.The polymer-quartz composite fiber with PM597 as the dye was manufactured by the same method,and the cladding was replaced by PM597 doped PEO.Lateral pumping was also used,and the results showed that only fluorescence was produced when the concentration was lower than the aggregation concentration.But when the concentration is higher than the aggregation concentration,the pumped composite optical fiber produces the random lasing.This result also confirmed our assumption of the external modification of common optical fibers.Subsequently,we continued to study RFL by replacing polymer materials,but for various reasons,it did not produce similar results to PEO.Finally,we conducted relevant studies on the stability of the random lasing of the composite fiber prepared by PM597 doped PEO.The experimental results showed that the composite optical fiber had excellent stability and repeatability of the RFL,without bleaching.