Interaction of copper(II) dodecyl sulfate with poly(ethylene oxide) and poly(vinylpyrrolidone) : self-diffusion fluorescence probing, and conductivity study
Interaction of copper(II) dodecyl sulfate with poly(ethylene oxide) and poly(vinylpyrrolidone) : self-diffusion fluorescence probing, and conductivity study
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十二烷基硫酸铜(II)与聚环氧乙烷和聚乙烯基吡咯烷酮的相互作用：自扩散荧光探测和电导率研究
作者：
N. Kamenka;I. Burgaud;C. Treiner;R. Zana
用电导法、芘荧光探针法和十二烷基硫酸根离子自扩散法研究了十二烷基硫酸铜（Cu（DS）2）与两种水溶性高分子聚乙烯吡咯烷酮（PVP）和聚氧化乙烯（PEO）在稀溶液中的相互作用。发现Cu（DS）2在H2O中的Krafft温度为23.9 ℃，并且在加入PVP后降低。由电导率和自扩散测定的Cu（DS）2在水溶液中的临界胶束浓度、胶束尺寸和电离度与文献报道的结果一致。由十二烷基硫酸根离子的自扩散系数数据得到了表面活性剂在聚合物上的键合分数和键合胶束的临界聚集浓度。结合等温线也被构建，表明随着表面活性剂浓度的增加，自由胶束出现聚合物饱和之前。芘荧光探测实验表明，PVP结合的Cu（DS）2聚集体内部的极性比十二烷基硫酸钠（NaDS）的弱。Cu（DS）2和两种聚合物之间的相互作用弱于NaDS的情况，可能是由于与单价钠离子相比，二价铜离子的水合程度更大。
The interaction of copper (II) dodecyl sulfate {Cu (DS) 2} with thetwo water-soluble polymers poly-(vinylpyrrolidone){PVP} and polyfethylene oxide){PEO} has been studiedin dilute solutions by conductivity, pyrene fluorescence probing, and dodecyl sulfate ion self-diffusion measurements. The Krafft temperature of Cu (DS) 2 in H20 was found to be 23.9 C and decreased upon addition of PVP. The critical micelle concentration, micelle size, and ionization degree of Cu (DS) 2 in aqueous solution, determined by electrical conductivity and self-diffusion, were found to be in agreement with previously reported results. The fraction of surfactant boundto the polymers and the critical aggregation concentration for bound micelles were obtained from the dodecyl sulfate ion self-diffusion coefficients data. Binding isotherms were also constructed, showing that as the surfactant concentration is increased, free micelles appear before polymer saturation. Pyrene fluorescence probing experiments suggested that the interior of thePVP-bound aggregates of Cu (DS) 2 is less polar than in the case of sodium dodecyl sulfate {NaDS}. Interactions between Cu (DS) 2 and both polymers are weaker than in the case of NaDS, possibly as a consequence of the larger degree of hydration of the divalent cupric counterion as compared to the monovalent sodium ion.