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Mechanically tunable three-dimensional elastomeric network/air structures via interference lithography.

Ji-Hyun Jang·Chaitanya K Ullal·Taras Gorishnyy·Vladimir V Tsukruk·Edwin L Thomas
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Abstract

We show how to employ an interference lithographic template (ILT) as a facile mold for fabricating three-dimensional bicontinuous PDMS (poly(dimethylsiloxane)) elastomeric structures and demonstrate the use of such a structure as a mechanically tunable PDMS/air phononic crystal. A positive photoresist was used to make the ILT, and after infiltration with PDMS, the resist was removed in a water-based basic solution which avoided PDMS swelling or pattern collapse occurring during the ILT removal process. Since the period of the structure is approximately 1 microm, the density of states of gigahertz phonons are altered by the phononic PDMS/air crystal. Brillouin light scattering (BLS) was employed to measure phononic modes of the structure as a function of mechanical strain. The results demonstrate that the phononic band diagram of such structures can be tuned mechanically.

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AirCrystallizationDimethylpolysiloxanesElasticityElastomersLightMaterials TestingMechanicsMolecular ConformationNanostructuresNanotechnologyParticle SizePhotochemistryPhotographyScattering, RadiationSiliconesStress, MechanicalSurface PropertiesJournal ArticleResearch Support, Non-U.S. Gov'tResearch Support, U.S. Gov't, Non-P.H.S.

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Ji-Hyun Jang, Chaitanya K Ullal, Taras Gorishnyy, Vladimir V Tsukruk, Edwin L Thomas. 2006. Mechanically tunable three-dimensional elastomeric network/air structures via interference lithography.. https://doi.org/10.1021/nl052577q

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