Magnetic composite polymer membrane actuators with applications to microfluidic devices

This thesis demonstrates new materials and microfabrication techniques for integrating membrane-type magnetic composite polymer (M-CP) actuators into microfluidic devices and systems. A membrane actuator with a powerful stroke volume that displaces 7.4 µL of water under a 110mT external magnetic field is developed and demonstrated in a hybrid M-CP/thermoplastic microfluidic device and in an all-PDMS microfluidic device. To achieve injection mouldable M-CP devices, a new M-CP is developed that consists of an injection mouldable off-thiol-ene-epxoy (OSTE+) polymer resin that is embedded with 25 weight-% rare earth magnet particles to be permanently magnetized. To support the rapid prototyping of PDMS and OSTE+ polymer microfluidic devices, a new type of micromould is developed that uses laser ablation of tape to deliver low cost, ultra-rapid moulds. These developments facilitate future commercial mass production through integration with thermoplastic polymers favored by the microfluidics industry in a scalable, “design-to-manufacture” scheme.