Viscosity of Ring Polymer Melts

Citations Over TimeTop 1% of 2013 papers

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 η_0,linear to their ring counterparts η_0,ring at isofrictional conditions is discussed as function of the number of entanglements Z. In the unentangled regime η_0,linear/η_0,ring is virtually constant, consistent with the earlier data, atomistic simulations, and the theoretical expectation η_0,linear/η_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 1η_0,linear/η_0,ring ~ Z1.2±0.3, is weaker than the scaling prediction (η_0,linear/η_0,ring ~ Z1.6±0.3 ) and the simulations (η_0,linear/η_0,ring ~ Z2.0±0.3 ). Nevertheless, the present collection of state-of-the- art experimental data unambiguously demonstrates that rings exhibit a universal trend clearly departing from that of their linear counterparts, and hence it represents a major step toward resolving a 30-year old problem.

Related Papers

• → Hydrodynamic radius of circular DNA is larger than that of linear DNA(2005)37 cited
• → Conformation of the Linear-Dendritic Block Copolymers of Hyperbranched Polyphenylenegermane and Linear Poly(methylmethacrylate)(2014)7 cited
• → The geometry of linear polymers—VIII. An approximate statistical theory of volume effects in linear polymer chains(1962)24 cited
• → Brownian Dynamics Study of Mixed Linear-Hyperbranched Polymers(2001)14 cited
• → A comparison of linear and non-linear magnification on target detection performance in visual inspection(2004)1 cited