Prof.Maria Helena Godinho: New Stimuli-Responsive Cellulosic Liquid Crystalline Materials

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    New Stimuli-Responsive Cellulosic Liquid Crystalline Materials

    Prof.Maria Helena Godinho, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Portugal

Cellulose is an abundant and renewable resource found in most parts of the world. Moreover cellulosic systems can generate liquid crystalline phases. In this work we report on liquid crystalline cellulosic fibers and jets, which mimic the shapes of helical tendrils of climbing plants such as Passiflora edulis and other structures with intrinsic curvature [1,2]. Liquid crystalline and isotropic cellulosic precursor solutions of curved and straight fibers are examined using nuclear magnetic resonance imaging (MRI) and polarizing optical microscopy (POM) techniques to determine morphological and structural features contributing to fiber curvature. In the case of liquid-crystalline cellulosic fibers, this is due to a core of disclination forming off-axis along the filament [3]. We also highlight the critical dependence of the helical structures on temperature and other external stimulus.

[1] J.P. Canejo, J.P. Borges, M.H. Godinho, P. Brogueira, P.I.C. Teixeira, E.M. Terentjev, Advanced Materials, 2008, 20, 4821.

[2] M.H. Godinho, J.P. Canejo, L.F.V. Pinto, J.P. Borges, P.I.C. Teixeira, Soft Matter, 2009, 5, 2772.

[3] M.H. Godinho, J.P. Canejo, G. Feio, E.M. Terentjev, Soft Matter, 2010, 6, 5965.