Viscosity of ring polymer melts.

ABSTRACT: We have measured the linear rheology of critically purified ring polyisoprenes, polystyrenes and polyethyleneoxides of different molar masses. The ratio of the zero-shear viscosities of linear polymer melts ?0,linear to their ring counterparts ?0,ring at isofrictional conditions is discussed as function of the number of entanglements Z. In the unentangled regime ?0,linear/?0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation ?0,linear/?0,ring=2. In the entanglement regime, the Z-dependence of rings viscosity is much weaker than that of linear polymers, in qualitative agreement with predictions from scaling theory and simulations. The power-law extracted from the available experimental data in the rather limited range 1

SUBMITTER: Pasquino R 

PROVIDER: S-EPMC4517619 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature