(315i) Synthesis of Magnetic Glass Microcomponents Using the Stop-Flow Lithography and Sol-Gel Process

We have synthesized magnetic glass microcomponents by using the stop-flow lithography and sol-gel process. Polymeric microparticles with complex shape were first photopolymerized in a PDMS microchannel by photolithography. The prepolymer solutions consisted of PEGDA as the monomer and the crosslinker, the photoinitiator, the precursor of silicon-dioxide (TEOS) and the bridging agents that maintain the affinity between PEGDA and TEOS molecules. The polymeric particles were then heated to generate glass microparticles. The heating step does not only condense TEOS to SiO₂ but also burn out the polymer and leave a whole glass structure. The resulting glass microparticles were found shrinking significantly from their original size but having much greater mechanical strength. By adding magnetic particles into the prepolymer solutions, we were also able to manufacture magnetic glass particles that can be controlled remotely by magnetic field. We have made magnetic glass microgears and explored the possibility of using them to serve as the power source of micromechanical machines.