Cieplak Marek, Hoang Trinh Xuan, Robbins Mark O
Institute of Physics, Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warsaw, Poland.
Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Jul;70(1 Pt 1):011917. doi: 10.1103/PhysRevE.70.011917. Epub 2004 Jul 30.
Mechanical stretching of self-interacting homopolymers is studied through molecular dynamics simulations in which the polymers are pulled with constant speed. At temperatures below the compactification temperature, the force-extension curves show a plateau that corresponds to the situation in which the polymer adopts "ball-string" configurations. The dependence of rupture distances on contact order and the effects of temperature are similar to those found in the case of model proteins. The dependence of behavior on the pulling speed is logarithmic. In the entropic limit, above the compactification temperature, the rupturing of contacts shows a monotonic decrease of extension with the contact order. The attainment of this limit depends on the system size and the pulling speed.
通过分子动力学模拟研究了自相互作用均聚物的机械拉伸，其中聚合物以恒定速度被拉伸。在低于致密化温度的温度下，力-伸长曲线显示出一个平台，这对应于聚合物采用“球-链”构型的情况。断裂距离对接触序的依赖性以及温度的影响与模型蛋白质的情况相似。行为对拉伸速度的依赖性是对数关系。在熵极限下，高于致密化温度时，接触的断裂显示出伸长随接触序单调下降。达到这个极限取决于系统大小和拉伸速度。
