Flow control in microdevices using thermally responsive triblock copolymers

Author

Stoeber, Boris ; Yang, Zhihao ; Liepmann, Dorian ; Muller, Susan J.

Author_Institution

Dept. of Chem. Eng., Univ. of California, Berkeley, CA, USA

Volume

14

Issue

2

fYear

2005

fDate

4/1/2005 12:00:00 AM

Firstpage

207

Lastpage

213

Abstract

Active and passive microflow control has been demonstrated using gel formation by dilute aqueous solutions of triblock copolymers at elevated temperatures. Solutions of a poly(ethylene oxide)₁₀₆-poly(propylene oxide)₇₀-poly(ethylene oxide)₁₀₆ polymer, which has the trade name Pluronic® F127, have been used as a sample system. Flow in a microchannel has been stopped in less than 33 ms by introducing heat with an integrated electric heater. Viscous heating under high shear rates also induces gel formation, which has been used for passive automated flow control in a microchannel.

Keywords

channel flow; electric heating; flow control; microfluidics; microvalves; polymer blends; polymer gels; 106 polymer; 106-polypropylene oxide; 70-polyethylene oxide; Pluronic F127; active microflow control; active microvalve; dilute aqueous solution; high shear rates; integrated electric heater; microchannel flow; microdevices; microfluidics; passive automated flow control; passive microflow control; polyethylene oxide; reversible gel formation; thermally responsive triblock copolymers; viscous heating; Actuators; Automatic control; Chemical engineering; Microchannel; Microfluidics; Microvalves; Polymers; Resistance heating; Temperature control; Valves; Active microvalve; microfluidics; passive microflow control; reversible gel formation;

fLanguage

English

Journal_Title

Microelectromechanical Systems, Journal of

Publisher

ieee

ISSN

1057-7157

Type

jour

DOI

10.1109/JMEMS.2004.839330

Filename

1416897