Nonmonotonic dependence of polymer-glass mechanical response on chain bending stiffness

作者：Ness Christopher; Palyulin Vladimir V; Milkus Rico; Elder Robert; Sirk Timothy^*; Zaccone Alessio

来源：Physical Review E, 2017, 96(3): 030501.

DOI：10.1103/PhysRevE.96.030501

We investigate the mechanical properties of amorphous polymers by means of coarse-grained simulations and nonaffine lattice dynamics theory. A small increase of polymer chain bending stiffness leads first to softening of the material, while hardening happens only upon further strengthening of the backbones. This nonmonotonic variation of the storage modulus G' with bending stiffness is caused by a competition between additional resistance to deformation offered by stiffer backbones and decreased density of the material due to a necessary decrease in monomer-monomer coordination. This counterintuitive finding suggests that the strength of polymer glasses may in some circumstances be enhanced by softening the bending of constituent chains.

• 出版日期2017-9-13