Physics Department, TU Dortmund University, 44221 Dortmund, Germany.
Phys Rev Lett. 2014 Mar 7;112(9):094303. doi: 10.1103/PhysRevLett.112.094303.
We investigate wrinkling of two-dimensional random and triangular semiflexible polymer networks under shear. Both types of semiflexible networks exhibit wrinkling above a small critical shear angle, which scales with an exponent of the bending modulus between 1.9 and 2.0. Random networks exhibit hysteresis at the wrinkling threshold. Wrinkling lowers the total elastic energy by up to 20% and strongly affects the elastic properties of all semiflexible networks such as the crossover between bending and stretching dominated behavior. In random networks, we also find evidence for metastable wrinkled configurations. While the disordered microstructure of random networks affects the scaling behavior of wrinkle amplitudes, it has little effect on wrinkle wavelength. Therefore, wrinkles represent a robust, microstructure-independent assay of shear strain or elastic properties.
我们研究了二维随机和三角形半刚性聚合物网络在剪切下的起皱情况。这两种半刚性网络在一个小的临界剪切角之上都会出现起皱现象，该临界剪切角的标度指数介于弯曲模量的 1.9 和 2.0 之间。随机网络在起皱阈值处表现出滞后现象。起皱将总弹性能量降低了多达 20%，并强烈影响所有半刚性网络的弹性性质，例如弯曲和拉伸主导行为之间的交叉点。在随机网络中，我们还发现了亚稳态起皱结构的证据。虽然随机网络的无序微观结构会影响皱纹幅度的标度行为，但对皱纹波长几乎没有影响。因此，皱纹是一种稳健的、与微观结构无关的剪切应变或弹性性质的检测方法。
