1. Strain hardening in startup shear of long-chain branched polymer solutions
- Author
-
Hyojoon Lee, Roderic P. Quirk, Taihyun Chang, Shi-Qing Wang, Shiwang Cheng, Gengxin Liu, Hongde Xu, and Hongwei Ma
- Subjects
chemistry.chemical_classification ,Materials science ,Gaussian ,General Physics and Astronomy ,Polymer ,Mechanics ,Conformational entropy ,Strain hardening exponent ,Branching (polymer chemistry) ,Extensibility ,symbols.namesake ,chemistry ,Shear (geology) ,symbols ,Long chain - Abstract
We show for the first time that entangled polymeric liquids containing long-chain branching can exhibit strain hardening upon startup shear. As the significant long-chain branching impedes chain disentanglement, Gaussian coils between entanglements can deform to reach the finite extensibility limit where the intrachain retraction force exceeds the value expected from the usual conformational entropy loss evaluated based on Gaussian chain statistics. The phenomenon is expected to lead to further theoretical understanding.
- Published
- 2013