Share Email Print

Proceedings Paper

Rapid bonding of polydimethylsiloxane (PDMS) to various stereolithographically (STL) structurable epoxy resins using photochemically cross-linked intermediary siloxane layers
Author(s): Elisabeth Wilhelm; Christiane Neumann; Kai Sachsenheimer; Kerstin Länge; Bastian E. Rapp
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

In this paper we present a fast, low cost bonding technology for combining rigid epoxy components with soft membranes made out of polydimethylsiloxane (PDMS). Both materials are commonly used for microfluidic prototyping. Epoxy resins are often applied when rigid channels are required, that will not deform if exposed to high pressure. PDMS, on the other hand, is a flexible material, which allows integration of membrane valves on the chip. However, the integration of pressure driven components, such as membrane valves and pumps, into a completely flexible device leads to pressure losses. In order to build up pressure driven components with maximum energy efficiency a combination of rigid guiding channels and flexible membranes would be advisable. Stereolithographic (STL) structuring would be an ideal fabrication technique for this purpose, because complex 3D-channels structures can easily be fabricated using this technology. Unfortunately, the STL epoxies cannot be bonded using common bonding techniques. For this reason we propose two UV-light based silanization techniques that enable plasma induced bonding of epoxy components. The entire process including silanization and corona discharge bonding can be carried out within half an hour. Average bond strengths up to 350 kPa (depending on the silane) were determined in ISO-conform tensile testing. The applicability of both techniques for microfluidic applications was proven by hydrolytic stability testing lasting more than 40 hours.

Paper Details

Date Published: 6 March 2014
PDF: 7 pages
Proc. SPIE 8976, Microfluidics, BioMEMS, and Medical Microsystems XII, 89760A (6 March 2014); doi: 10.1117/12.2044661
Show Author Affiliations
Elisabeth Wilhelm, Karlsruhe Institute of Technology (Germany)
Christiane Neumann, Karlsruhe Institute of Technology (Germany)
Kai Sachsenheimer, Karlsruhe Institute of Technology (Germany)
Kerstin Länge, Karlsruhe Institute of Technology (Germany)
Bastian E. Rapp, Karlsruhe Institute of Technology (Germany)

Published in SPIE Proceedings Vol. 8976:
Microfluidics, BioMEMS, and Medical Microsystems XII
Bonnie L. Gray; Holger Becker, Editor(s)

© SPIE. Terms of Use
Back to Top