We present low temperature transfer bonding of porous silicon membranes to polymeric microfluidic devices, using neither adhesives nor bond surface treatment. The transfer is enabled by a novel dual cure ternary monomer system containing thiolene and epoxy. The ability of the epoxy to react with almost any dry substrate provides a very versatile fabrication method. We characterize the two stage curing mechanism, describe the device fabrication, and evaluate the bond strength.