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Programming magnetic anisotropy in polymeric microactuators


Polymeric microcomponents are widely used in microelectromechanical systems (MEMS) and lab-on-a-chip devices, but they suffer from the lack of complex motion, effective addressability and precise shape control1,2. To address these needs, we fabricated polymeric nanocomposite microactuators driven by programmable heterogeneous magnetic anisotropy. Spatially modulated photopatterning3 was applied in a shape-independent manner to microactuator components by successive confinement of self-assembled magnetic nanoparticles in a fixed polymer matrix. By freely programming the rotational axis of each component, we demonstrate that the polymeric microactuators can undergo predesigned, complex two- and three-dimensional motion.

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Figure 1: Schematic of the fabrication of polymeric magnetic microactuators.
Figure 2: Various types of actuation using programmable magnetic anisotropy.
Figure 3: Polymeric micro-looper.


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This work was partly supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MEST) (2011-0016491), supported by the Korea Science and Engineering Foundation (KOSEF) grant funded by the Korea government (MEST) (2011-0000545), and supported by Global Frontier Project grant (NRF-M1AXA002-2010-0029797) of the National Research Foundation funded by the Ministry of Education, Science and Technology of Korea.

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Jiyun Kim, S.E. Chung and S.K. designed the experiment. Jiyun Kim and S.E. Chung performed the experiments and analysis. S-E. Choi synthesized the magnetic material and gave key advice for the experimental design. H.L. and Junhoi Kim gave key advice for the experimental design. Junhoi Kim also investigated the magnetic properties of the nanoparticles.

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Correspondence to Sunghoon Kwon.

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The authors declare no competing financial interests.

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Kim, J., Chung, S., Choi, SE. et al. Programming magnetic anisotropy in polymeric microactuators. Nature Mater 10, 747–752 (2011).

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