Microwave bonding of poly(methylmethacrylate) microfluidic devices using a conductive polymer

Component binding within microfluidic devices is a problem that has long been seeking a solution. In this investigation, the use of microwave radiation to seal PMMA components has been investigated using polyaniline as an absorber that is capable of inducting interfacial bonding. Straight microchannels were machined into PMMA using a Datron CAT3DM6 CNC machine with widths and depths across a range of 100–1000 μm. Prototype fluidic devices were prepared with channel patterns utilizing varying feature sizes, bends and flow profiling to demonstrate the application of the technique to real microfluidic devices. Experimental data illustrated the successful bonding of channels in the range stated previously and bonding (tensile) strength was assessed via pull tests on bonded PMMA using an Engstrom Zwick 100 tensile testing system (Engstrom Ltd, US). Coherent, defect free seals were attained with breakage tests requiring an excess of 1 kN force.

Research highlights
► Microwave bonding of polymer microfluidic devices.
► Rapid and low cost device fabrication.
► Localized thermal bonding method.