Faculty of Physics, A. Mickiewicz University, Umultowska 85, 61-614 Poznań, Poland.
Phys Chem Chem Phys. 2018 Jul 4;20(26):17818-17828. doi: 10.1039/c8cp02440e.
G3-G9 dendritic polyelectrolytes accompanied by counterions are investigated using the Poisson-Boltzmann-Flory theory. Within this approach we solve numerically the Poisson-Boltzmann equation for the mean electrostatic potential and minimize the Poisson-Boltzmann-Flory free energy with respect to the size of the molecules. Such a scheme enables us to inspect the conformational and electrostatic properties of the dendrimers in equilibrium based on their response to varying the dendrimer generation. The calculations indicate that the G3-G6 dendrimers exist in the polyelectrolyte regime where absorption of counterions into the volume of the molecules is minor. Trapping of ions in the interior region becomes significant for the G7-G9 dendrimers and signals the emergence of the osmotic regime. We find that the behavior of the dendritic polyelectrolytes corresponds with the degree of ion trapping. In particular, in both regimes the polyelectrolytes are swollen as compared to their neutral counterparts and the expansion factor is maximal at the crossover generation G7.
使用泊松-玻尔兹曼-弗洛里理论研究了伴随抗衡离子的 G3-G9 树枝状多聚物。在这种方法中，我们数值求解了平均静电势的泊松-玻尔兹曼方程，并针对分子的大小最小化了泊松-玻尔兹曼-弗洛里自由能。这种方案使我们能够根据树枝状分子的响应来检查处于平衡状态的树枝状聚合物的构象和静电性质，这些响应与改变树枝状分子的代有关。计算表明，G3-G6 树枝状分子存在于聚电解质区，其中抗衡离子少量地被吸收到分子的体积中。对于 G7-G9 树枝状分子，离子在内区的捕获变得显著，标志着渗透压区的出现。我们发现，树枝状聚电解质的行为与离子捕获的程度相对应。具体来说，在这两种区中，聚电解质相对于它们的中性对应物都会膨胀，并且在交叉代 G7 处的膨胀因子最大。
