We report a new approach to fabricate suspended composite membranes consisting of carbon-coated iron nanopowder uniformly dispersed in a polydimethylsiloxane matrix. The approach is based on the use of selectively photopolymerized thick SU-8 layer wherein the unexposed to ultraviolet light area represents the sacrificial layer. Circular composite membranes of different sizes are designed, fabricated, and characterized. The membranes’ deflections upon the application of an external magnetic field, measured by optical microscopy, show a quadratic dependence on the diameter, in agreement with the theory. Tensile tests proved that the fillers do not affect the elastic properties of the matrix, since the Young’s modulus of the composite material is similar with the one of the pure polymer. The versatile approach presented in this work allows to easily and rapidly fabricate suspended composite membranes that provide diaphragm materials with excellent performances, which can find broad applicability in microfluidic applications (valves, micro-pumps) and in MEMS technology (tactile displays, mobile devices).
Microfabrication of magnetically actuated PDMS–Iron composite membranes
DE VITTORIO, Massimo;
2012-01-01
Abstract
We report a new approach to fabricate suspended composite membranes consisting of carbon-coated iron nanopowder uniformly dispersed in a polydimethylsiloxane matrix. The approach is based on the use of selectively photopolymerized thick SU-8 layer wherein the unexposed to ultraviolet light area represents the sacrificial layer. Circular composite membranes of different sizes are designed, fabricated, and characterized. The membranes’ deflections upon the application of an external magnetic field, measured by optical microscopy, show a quadratic dependence on the diameter, in agreement with the theory. Tensile tests proved that the fillers do not affect the elastic properties of the matrix, since the Young’s modulus of the composite material is similar with the one of the pure polymer. The versatile approach presented in this work allows to easily and rapidly fabricate suspended composite membranes that provide diaphragm materials with excellent performances, which can find broad applicability in microfluidic applications (valves, micro-pumps) and in MEMS technology (tactile displays, mobile devices).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
