| AVS 61st International Symposium & Exhibition | |
| Manufacturing Science and Technology | Thursday Sessions |
| Session MS+PS+TF-ThM |
| Session: | Processes for Mesoscale Structure on Paper and Textiles |
| Presenter: | Chelsea Davis, National Institute of Standards and Technology (NIST) |
| Authors: | C.S. Davis, National Institute of Standards and Technology (NIST) J. Woodcock, National Institute of Standards and Technology (NIST) A.M. Forster, National Institute of Standards and Technology (NIST) M. Zammarano, National Institute of Standards and Technology (NIST) I. Sacui, National Institute of Standards and Technology (NIST) N. Chen, National Institute of Standards and Technology (NIST) SJ. Stranick, National Institute of Standards and Technology (NIST) J.W. Gilman, National Institute of Standards and Technology (NIST) |
| Correspondent: | Click to Email |
In fundamental composite theory, the nature of the interface is often the key parameter which determines the strength of the resulting composite structure. While it is possible to observe interfacial failure and characterize the areal coverage of the matrix on the surface of the reinforcement phase in conventional composite materials, directly quantifying interfacial strength and contact area in a nanocomposite becomes far more difficult. A novel solution developed at NIST has been to utilize Förster resonance energy transfer (FRET) imaging[1,2] by preferentially labeling the interface within a nanocomposite system, allowing direct imaging of the interface with an optical microscope.[3] Zammarano et al. have shown that the incorporation of a FRET dye pair onto the surface of a cellulosic nanoreinforcement phase (dye 1) and within a polymer matrix (dye 2) allows visualization of the nanoscopic interphase region as the two dyes transfer energy on the same scale as the interphase depth (1 nm-100 nm).[3,4]
Building upon this FRET-based interfacial characterization technique, our goal is to develop a globally nondestructive measurement system that allows the quantitative characterization of key interfacial properties; first, the wetting and surface contact formed between the nanocellulose and an epoxy matrix and second, the deformation of the interface on the nanoscale upon application of small mechanical strains. We are constructing a suite of mechanical strain tools to enable in situ mechanical interrogation with simultaneous FRET imaging. The development of the first of these tools, uniaxial tensile test will allow a preliminary observation of small strain effects on the interphase region regarding the fluorescent response of the FRET dye pair. As a first proof of concept, it has been shown that FRET can be used to observe nanoscopic interfacial fracture and to determine local (microscopic) stress concentration zones before macroscopic failure of the nanocomposite is observed.
This in situ FRET/mechanical deformation approach allows the use of an optical microscope to probe nanoscale features in a powerful way, enabling characterization of nanomaterials which will complement measurements made by electron microscopy and standard mechanical property testing methods.
Topic Area: Novel nanocomposites, Multi-technique characterization of nanostructured materials
[1] T. Förster, Ann. Phys.1948, 248.
[2] E. a Jares-Erijman, T. M. Jovin, Nat. Biotechnol.2003, 21, 1387.
[3] M. Zammarano, P. H. Maupin, L.-P. Sung, J. W. Gilman, E. D. McCarthy, Y. S. Kim, D. M. Fox, ACS Nano2011, 5, 3391.
[4] C. Berney, G. Danuser, Biophys. J.2003, 84, 3992.