"

Cookies ussage consent

Our site saves small pieces of text information (cookies) on your device in order to deliver better content and for statistical purposes. You can disable the usage of cookies by changing the settings of your browser. By browsing our site without changing the browser settings you grant us permission to store that information on your device.

I agree, do not show this message again.

Flow behavior of poly(ethylene oxide)–laponite nanocomposite solutions

S. MORARIU1,* , M. BERCEA1

Affiliation

  1. ”Petru Poni” Institute of Macromolecular Chemistry, 41-A Grigore Ghica Voda Alley, 700487 Iasi, Romania

Abstract

The flow behavior of poly(ethylene oxide) (PEO)-Laponite RD-water mixtures with polymer concentrations between 0.05 wt% and 1 wt% in the range of temperature 10°C-50°C is investigated. The evolution of the elastic modulus, the viscous modulus and the loss tangent as a function of oscillation frequency for the studied mixtures gives some indications about the dispersions structure. The rheological results allow to evidence of two critical concentrations: c1=0.113 wt% PEO and c2=0.51 wt% PEO. Below 30 °C, all mixtures exhibit the gel-like properties. For concentrations lower than c1, the mixtures containing PEO are also the gels at temperatures above 30°C. The structure for mixtures with PEO concentrations between c1 and c2 is strongly influenced by temperature and these systems are considered “critical gels” at temperature higher than 30 °C. The rheological behavior of the mixtures with the polymer concentration above c2 is affected by the formation of PEO clusters at higher temperatures..

Keywords

Laponite, Poly(ethylene oxide), Gel, Viscoelastic properties.

Submitted at: Nov. 2, 2006
Accepted at: April 15, 2007

Citation

S. MORARIU, M. BERCEA, Flow behavior of poly(ethylene oxide)–laponite nanocomposite solutions, Journal of Optoelectronics and Advanced Materials Vol. 9, Iss. 4, pp. 1005-1009 (2007)