Preparation And Fluorescence Properties Of Polyaryletherketone And Rare Earth-Coordinated Polyaryletherketone Complexes

Polyaryletherketone?PAEK?,as a class of high performance thermoplastic engineering plastics,possess high heat-resistance,excellent mechanical properties,good chemical resistance,etc.and have broad application in aerospace,electronic fields,automobile manufacturing etc.,and the demand is also increasing.Fluorescein with twisted biphenol structure was introduced into main chain of new polymer?PEK-F?to improve the solubility of PAEK,and to endow excellent fluorescence properties.Moreover,introducing the carboxyl group into the backbones made PAEK functionalized.The novel rare earth coordination polymer was prepared by using the polymer with carboxyl group as macromolecular ligand and rare earth ions as the luminescent centers.The contents and conclusions of this dissertation are as follows:1.PEK-F and PEK-C were prepared via solution nucleophilic polycondensation from phenolphthalein and fluorescein with DFDPK,respectively.The chemical structures and properties of PEK-F and PEK-C were confirmed by means of FT-IR,1H NMR,DSC,TGA,XRD et,al methods.The number-average molecular weights?Mn?and the weight-average molecular weight?Mw?of PEK-C and PEK-F are 55.2 kg/mol,37.1 kg/mol and 91.0 kg/mol,106.9 kg/mol,respectively.PEK-C and PEK-F had high glass transition temperatures 232 ? and 273 ?,respectively.The two polyaryletherketones were stable to 450 ? as tested by 5 % weight loss temperatures in nitrogen.The X-ray diffraction patterns displayed that they were amorphous in nature.PEK-C and PEK-F could dissolve in organic solvents such as DMF,DMSO,NMP at room temperature.The fluorescence properties were explored by fluorescence emission spectra.The results showed that the emission intensity of fluorescent polymer was highly dependent on concentration and the polarity of solvent.PEK-F with excellent fluorescence properties can be used as biochemical sensors to detect fenitrothion.2.Carboxyl-containing Polyaryletherketone?PEK-CF?was prepared according to the procedure described in our previous report.By using 1,10-phenanthroline?Phen?as small molecular ligands,the PEK-CF coordinated with the Eu³⁺ ion and Tb³⁺ ion to obtain the rare earth complexes.The rare earth had coordinated to polymer chain and distributed homogeneously were confirmed by IR and XRD.The thermal properties of PEK-CF and PEK-CF-Re³⁺-Phen were evaluated by DSC and TGA in N2 atmosphere.The 5% weight loss of PEK-CF appeared at the temperatures above 400 ?.The Tg of PEK-CF was 273 ?,but for PEK-CF-Re³⁺-Phen,no glass transition temperature was detected in the measurement range.indicating that PEK-CF and PEK-CF-Re³⁺-Phen possess good thermal stability.PEK-CF and PEK-CF-Re³⁺-Phen showed good solubility and could dissolve in DMF,DMSO,NMP.PEK-CF-Re³⁺-Phen photophysical properties were systematically studied by means of excitation and emission spectra,and the characteristic peak of Eu³⁺ and Tb³⁺ were observed.The color-tunable rare earth co-coordinated polymeric materials were prepared by changing the ratios of Eu³⁺ and Tb³⁺.