用时间分辨荧光光谱研究乙酸-水溶液的聚合特性

Research on polymerization characteristics of acetic acid-water solution with time resolved fluorescence spectrometer

对284nm激发光照射不同体积百分比乙酸-水溶液的峰值荧光强度时间衰变曲线进行了实验测量,并检测了不同紫外光激励下334nm荧光强度随时间的衰变过程,将获得的荧光衰减动力学曲线采用指数拟合方法进行了解卷积处理,测试了相应的荧光寿命。分析了乙酸-水溶液中线状二聚物(LD)缔合结构的变化规律,计算了混合物质中不同组分的浓度百分比和不同组分所发射荧光强度的百分比。结果表明,在284nm激发光照射下,乙酸体积百分比为80%时荧光光子对应的寿命最长为10.02ns,与LD缔合结构达到最大体积百分比有关;304nm和316nm的紫外光激发时对应的平均寿命分别为8.00ns和6.64ns,不同组分所发射荧光强度对激发光波长的变化较敏感。

The time decay curves of fluorescence intensity of acetic acid-water solution induced by the exciting light with wavelength of 284 nm in different volume percentages are studied,and the decay processes of fluorescence intensity are detected at the emission peak of 334 nm induced by the exciting light with different wavelengths experimentally. It is fitted by an exponential function and the analyzed data is obtained by deconvolution. Through theoretical analysis, the variation of linear dimer （LD） molecular as- sociation is analyzed in acetic acid-water solution. Both the relative concentration and the relative fluores- cence intensity of different components in acetic acid-water solution are calculated, respectively. The resluts show that the fluorescence lifetime at the acetic acid volume percentage of 80% with the exciting light wavelength of 284 nm is 10. 02 ns, related to the maximum volume percentage of LD association structure. The lifetime values of the the emission peaks induced by the exciting light of 304 nm and 316 nm are 8. 00 ns and 6. 64 ns, respectively. The fluorescence intensity is more sensitive to the exciting light wavelength. The research contributes to the study of the molecular structure characteristics of acetic acid-water polymerization.