Sheveleva Nadezhda N, Dolgushev Maxim, Lähderanta Erkki, Markelov Denis A
St. Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia.
Department of Physics, LUT University, Box 20, 53851 Lappeenranta, Finland.
Phys Chem Chem Phys. 2022 Jun 1;24(21):13049-13056. doi: 10.1039/d2cp00805j.
Functionalizing the internal structure of classical dendrimers is a new way of tailoring their properties. Using atomistic molecular dynamics simulations, we investigate the rheological behavior of functionalized dendrimer (FD) melts obtained by modifying the branching of carbosilane dendrimers (CSD). The time (relaxation modulus ()) and frequency (storage ' and loss '' moduli) dependencies of the dynamic modulus are obtained. Fourth generation FD melts present a region where ' > ''. In contrast, their non-functionalized counterparts (, classical dendrimers with regular branching) do not show such a region. The comparative analysis of FD and CSD suggests that the internal densification due to functionalization prevents the penetration of branches and causes FD to behave like colloidal particles in a crowded environment. Since CSD have no special interactions, we expect that this effect will be common for other dendrimer macromolecules.
使经典树枝状大分子的内部结构功能化是一种定制其性质的新方法。通过原子分子动力学模拟，我们研究了通过修饰碳硅烷树枝状大分子（CSD）的支化得到的功能化树枝状大分子（FD）熔体的流变行为。获得了动态模量的时间（松弛模量（））和频率（储能模量‘和损耗模量’’）依赖性。第四代FD熔体存在一个‘ > ’’的区域。相比之下，它们未功能化的对应物（，具有规则支化的经典树枝状大分子）则没有显示出这样的区域。FD和CSD的对比分析表明，功能化导致的内部致密化阻止了支链的穿透，并使FD在拥挤环境中表现得像胶体颗粒。由于CSD没有特殊相互作用，我们预计这种效应对于其他树枝状大分子将是普遍的。
