Abstract
Regenerated silk fibroin solutions (RSF) are produced by dissolving degummed silk fibers in water. We have observed that RSF solutions at a concentration less than 15 % by weight exhibit an unusual gel-like response in conventional shear rheology measurements. At higher concentrations, the response is predominantly viscous (or liquid-like). We have probed this counterintuitive behavior of silk fibroin solutions by using microrheology, and interfacial rheometry. Scattering techniques were also used to understand the microstructure of RSF solutions as a function of the concentration. Our studies suggest that the gel-like response of the RSF solution may result from the formation of an interfacial film at the air–solution interface, which dominates the bulk rheological response.
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Acknowledgments
AN thanks Dr. V. Aswal (BARC) for help with the SANS experiments. We thank CSRTI for generous supplies of B. mori cocoons.
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Nisal, A., Kalelkar, C., Bellare, J. et al. Rheology and microstructural studies of regenerated silk fibroin solutions. Rheol Acta 52, 833–840 (2013). https://doi.org/10.1007/s00397-013-0723-5
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DOI: https://doi.org/10.1007/s00397-013-0723-5