两亲性香豆胶衍生物溶液中的缔合行为  

Self-Aggregation of Amphiphilic Fenugreek Gum Derivatives in Solutions

作　　者：史学峰[1] 吴文辉[1] 宫瑞英[1] 王建全[1] 付海民[1] 

机构地区：[1]北京理工大学材料科学与工程学院,北京100081

出　　处：《功能高分子学报》2008年第2期152-158,共7页Journal of Functional Polymers

摘　　要：以共价酯键方式将长链十二烷基与十六烷基引入羧甲基化香豆胶的大分子骨架上,制得了不同取代度的两亲性香豆胶衍生物(HmCmFG)。采用稳态荧光法,通过探针芘的发射光谱与激发光谱研究了HmCmFG在NaCl溶液中的疏水缔合行为。结果表明:增加疏水烷基链长、提高烷基取代度或增大NaCl浓度均有利于疏水缔合作用的增强,使由芘激发谱中荧光响应值显著变化得出的临界缔合浓度降低。在一定HmCmFG浓度(cP)范围内,芘在疏水微区与水相中的浓度比值(cm/cw)与cnp成正比关系(n为幂指数),拟合计算的荧光响应曲线与实验结果相符合,得出芘的分配系数(KP)随疏水烷基取代度增加而增大。Amphiphilic fenugreek gum derivatives （HmCmFG） were synthesized by covalent bonding of dodecyl or cetyl chains onto carboxymethyl fenugreek gum. Hydrophobically associating behaviors of HmCmFG in solutions of different NaCl concentrations were studied by steady-state fluorescence emission and excitation spectra using pyrene as fluorescence probe. The results show that the increasing of length and substitution degree of alkyl chains and NaCl concentration are in favor of strengthening intra-or inter-molecular aggregation of HmCmFG, which resulted in decreasing of critical aggregation concentrations, according to the significant change of fluorophore response in the excitation spectra of pyrene. Over certain range of HmCmFG concentration cp, it was found that the ratio between the concentration of pyrene in hydrophobic microdomains and in water, cm/cw, is proportional to cp^n The partition coefficients of pyrene, Kp, increased with the increasing of substitution degree of alkyl chains.

关 键 词：香豆胶 两亲性 缔合 稳态荧光 

分 类 号：O648[理学—物理化学]