Elucidation of multiple-point interactions of pyranine fluoroprobe during the gelation.
Elucidation of multiple-point interactions of pyranine fluoroprobe during the gelation.
复制标题
DOI：
10.1016/j.saa.2008.09.012
复制
发表时间：
2009-03
期刊：
影响因子：
--
通讯作者：
Y. Yılmaz;Nihan Uysal;A. Gelir;Orhan Guney;D. Aktaş;Savas Gogebakan;Aylin Oner
中科院分区：
文献类型：
--
作者：
Y. Yılmaz;Nihan Uysal;A. Gelir;Orhan Guney;D. Aktaş;Savas Gogebakan;Aylin Oner
利用稳态荧光测量技术研究了丙烯酰胺自由基聚合过程中吡喃（8-羟基芘-1,3,6-三磺酸，三钠盐，3sPyOH）荧光探针与聚合物链的多点相互作用。我们观察到在发射光谱中从515nm到406nm有相当大的蓝移，这是由于3sPyOH的羟基氧和生长的AAm链的末端c原子之间形成了C-O醚键。此外，3sPyOH的三个电离磺酸基团（SO3−）与AAm链上的质子化酰胺基团之间发生离子（静电）相互作用。这些静电相互作用也会导致短波长的峰值逐渐红移，从406nm到430nm。结果表明，吡啶可以作为实时监测AAm体系聚合过程的探针，因为它既可以通过OH基团的化学结合来监测聚合过程的进展，也可以通过SO3−基团上的离子相互作用来监测聚合样品的短波长峰逐渐红移的局部密度变化。
We have studied the multiple-point interactions of the pyranine (8-hydroxypyrene-1,3,6-trisulfonic acid, trisodium salt; 3sPyOH) fluoroprobe with polymer chains during the free-radical polymerization of acrylamide (AAm) by using the steady state fluorescence measurements. We observed a considerable blue shift from 515nm to 406nm in the emission spectra due to a C–O ether bond formation between the hydroxylic oxygen of 3sPyOH and a terminal C-atom of the growing AAm chain. Furthermore ionic (electrostatic) interactions occur between the three ionized sulfonic acid groups (SO3−) of 3sPyOH and protonated amide groups on the AAm chains. These electrostatic interactions also cause a gradual red shift in the maximum of the short-wavelength-peak, from 406nm to 430nm. The results showed that the pyranine can be used as a probe for real time monitoring of the polymerization process of AAm system since it monitors both the progression of the polymerization via chemical binding over OH group and the change in the local density of the polymerizing sample by means of the gradual red shift in the short-wavelength-peak via ionic interactions over SO3−groups.