Kreer T, Balko S M
Leibniz-Institut für Polymerforschung (IPF) Dresden, Hohe Straße 6, 01069 Dresden, Germany.
Max-Bergmann Zentrum für Biomaterialien (MBZ) am IPF, Hohe Straße 6, 01069 Dresden, Germany.
ACS Macro Lett. 2013 Oct 15;2(10):944-947. doi: 10.1021/mz4004387. Epub 2013 Oct 4.
We present a novel scaling theory to describe the interaction free energy within a compressed polymer-brush bilayer. For semidilute brushes at intermediate and strong compressions, we predict that the interaction free energy scales with distance, , between the grafting surfaces as () ∼ ; i.e., the repulsive force, () ∼ , measured at the surfaces increases more strongly upon compression than predicted by the classical theory of Milner, Witten, and Cates. We find good agreement with experimental data and excellent agreement with numerical results, which follow our analytical predictions over a wide range of surface separations. The theory is based on the assumption of a strong correlation of the repulsive force and the interpenetration between the brushes. Using our numerical data, we can demonstrate this correlation with great precision.
我们提出了一种新颖的标度理论来描述压缩聚合物刷双层内的相互作用自由能。对于处于中等和强压缩状态的半稀刷，我们预测相互作用自由能随接枝表面之间的距离(z)按((z)\sim z^{-3})标度；即，在表面测量的排斥力(F(z)\sim z^{-4})，在压缩时比米尔纳、维滕和凯茨的经典理论预测的增加得更强。我们发现与实验数据吻合良好，与数值结果吻合极佳，在很宽的表面间距范围内，数值结果都符合我们的解析预测。该理论基于排斥力与刷之间相互穿透强相关性的假设。利用我们的数值数据，我们可以非常精确地证明这种相关性。
