影像科学与光化学 ›› 1987, Vol. 5 ›› Issue (3): 14-21.DOI: 10.7517/j.issn.1674-0475.1987.03.14

• 研究论文 • 上一篇    下一篇

疏水作用对光化学和光物理过程的影响 Ⅲ.长链β-萘甲酸烷基酯在簇集体中形成激基缔合物的热力学和动力学

徐承柏, 刘颙颙, 寿函森, 佟振合   

  1. 中国科学院感光化学研究所, 北京
  • 收稿日期:1986-07-19 修回日期:1987-01-14 出版日期:1987-08-20 发布日期:1987-08-20
  • 基金资助:
    国家自然科学基金

HYDROPHOBIC EFFECTS ON PHOTOPHYSICAL AND PHOTOCHEMICAL PROCESSES Ⅲ. KINETIC AND THERMODYNAMIC ASPECTS OF EXCIMER FORMATION OF ALKYL β-NAPHTHOATES WITH LONG CHAIN IN AGGREGATE

Xu CHENG-BAI, LIU YONG-YONG, SHOU HAN-SEN, TUNG ZHEN-HE   

  1. Institute of Photographic Chemistry, Academia Sinica, Beijing
  • Received:1986-07-19 Revised:1987-01-14 Online:1987-08-20 Published:1987-08-20

摘要: 在乙二醇-水(EG-H2O)和二甲基亚砜-水(DMSO-H20)混合溶剂中,β-萘甲酸十二烷基酯和十六烷基酯很容易发生簇集.本文研究了簇集体中的β-萘甲酸酯在—40℃3到90℃温度范围内的稳态荧光光谱和时间分辨荧光光谱以及荧光偏振,测定了激基缔合物形成和解离的速度常数,求出激基缔合物形成的活化能,焓变和熵变分别为10.9±0.4kJ/mol,—16.7±0.4kJ/mol和—50±4J/mol·K。A12和A16簇集体分别在—20℃和5℃发生相变.测定了不同温度下簇集体内的微观粘度。

关键词: 疏水作用, 簇集, β-甲酸烷基酯, 激基缔合物, 微观粘度

Abstract: Dodecyl β-naphthoate (A12) and hexadecyl β-naphthoate (A16) aggregate in poor solvents such as dimethyl sulfoxide-water (DMSO-H2O) and ethylene glycol-water (EG-H2O) mixtures. Their fluorescence under stationary and nonstationary condition as well as fluorescence polarization in a temperature range from -40℃ to 90℃ were investigated. The rate constants for excimer formation and dissociation were determined as a function of temperature. These in turn resulted in the data of activation energy Ea = 10.9±0.4kJ/mol, enthalpy change △H = -16.7±0.4 kJ/mol, and entropy changes △S = -50±4J/mol K for excimer formation. A12 and A16 undergo phase transitions at -20℃ and 5℃, respectively. The microviscosities in aggregate at various temperature were also determined.

Key words: hydrophobic interaction, aggregation, alkyl β-naphthoates, excimer, micro-viscosity