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本文研究了双-β-萘甲酸多缩乙二醇酯(P_n)在不同溶剂中的稳态和时间分辨荧光光谱。在甲醇中与在四氢呋喃中不同,P_n显示很强的激基缔合物荧光。表明在甲醇中疏水的两个末端发色团彼此靠近,亲水的多缩乙二醇链段包于两个发色团外部。热力学和动力学研究求出了P_n分子内激基缔合物形成的焓变是—20kJ/mol,活化能为～8.5kJ/mol,激基缔合物形成和离解的速度常数分别为4.5×10~8s~(-1)和3.1×10~8s~(-1)。
In this paper, steady-state and time-resolved fluorescence spectra of polyethylene naphthalate (P_n) in different solvents were studied. In methanol, unlike in tetrahydrofuran, P_n shows strong excimer fluorescence. Indicating that the two terminal chromophores that are hydrophobic in methanol are close to each other and the hydrophilic polyethlene glycol segment is outside the two chromophores. The thermodynamic and kinetic studies have found that the enthalpy change of formation of exciplex in P_n is -20kJ / mol and the activation energy is ~ 8.5kJ / mol. The velocity constants of formation and dissociation of exciplex are 4.5 × 10 ~ 8s ~ (-1) and 3.1 × 10 ~ 8s ~ (-1).