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1. Thermochromic Fibers via Electrospinning

   https://doi.org/10.3390/polym12040842  

   Nguyen, Jimmy ; Stwodah, Ratib M. ; Vasey, Christopher L. ; Rabatin, Briget E. ; Atherton, Benjamin ; D’Angelo, Paola A. ; Swana, Kathleen W. ; Tang, Christina ( April 2020 , Polymers)

   null (Ed.)

   Cholesteryl ester liquid crystals exhibit thermochromic properties related to the existence of a twisted nematic phase. We formulate ternary mixtures of cholesteryl benzoate (CB), cholesteryl pelargonate (CP), and cholesteryl oleyl carbonate (COC) to achieve thermochromic behavior. We aim to achieve thermochromic fibers by incorporating the liquid crystal formulations into electrospun fibers. Two methods of incorporating the liquid crystal (LC) are compared: (1) blend electrospinning and (2) coaxial electrospinning using the same solvent system for the liquid crystal. For blend electrospinning, intermolecular interactions seem to be important in facilitating fiber formation since addition of LC can suppress bead formation. Coaxial electrospinning produces fibers with higher nominal fiber production rates (g/hr) and with higher nominal LC content in the fiber (wt. LC/wt. polymer assuming all of the solvent evaporates) but larger fiber size distributions as quantified by the coefficient of variation in fiber diameter than blend electrospinning with a single nozzle. Importantly, our proof-of-concept experiments demonstrate that coaxially electrospinning with LC and solvent in the core preserves the thermochromic properties of the LC so that thermochromic fibers are achieved. 

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2. Peptide Modified Electrospun Glycopolymer Fibers

   https://doi.org/10.1002/mabi.201600327  

   Fiorani, Andrea ; Totsingan, Filbert ; Pollicino, Antonio ; Peng, Yifeng ; Focarete, Maria Letizia ; Gross, Richard A. ; Scandola, Mariastella ( October 2016 , Macromolecular Bioscience)

   Oligo(Glu₇₀‐co‐Leu₃₀), a peptide synthesized by protease catalysis, is functionalized at the N‐terminus with a 4‐pentenoyl unit and grafted to polyLSL[6′Ac,6″Ac], a glycopolymer prepared by ring‐opening metathesis polymerization of lactonic sophorolipid diacetate. First, polyLSL[6'Ac,6”Ac] fiber mats are fabricated by electrospinning. Oxidation of the fiber mats and subsequent reaction with cysteamine lead to thiol‐functionalized fiber mats with no significant morphology changes. Grafting of the alkene‐modified oligopeptide to thiol‐functionalized polyLSL[6′Ac,6″Ac] fiber mats is achieved via “thiol‐ene” click reaction. X‐ray photoelectron spectroscopy analysis to characterize peptide grafting reveals that about 50 mol% of polyLSL[6′Ac,6′′Ac] repeat units at fiber surfaces are decorated with a peptide moiety, out of which about 1/3 of the oligo(Glu₇₀‐co‐Leu₃₀) units are physically adsorbed to polyLSL[6′Ac,6′′Ac]. The results of this work pave the way to precise engineering of polyLSL fiber mats that can be decorated with a potentially wide range of molecules that tailor surface chemistry and biological properties.image

    

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3. Microfluidics in structured multimaterial fibers

   https://doi.org/10.1073/pnas.1809459115  

   Yuan, Rodger ; Lee, Jaemyon ; Su, Hao-Wei ; Levy, Etgar ; Khudiyev, Tural ; Voldman, Joel ; Fink, Yoel ( October 2018 , Proceedings of the National Academy of Sciences)
4. Classification of axisymmetric shapes of droplets on fibers. Could non-wettable fibers support axisymmetric droplets?

   https://doi.org/10.1063/5.0151950  

   Sun, Yueming ; Bazilevsky, Alexander V. ; Kornev, Konstantin G. ( July 2023 , Physics of Fluids)

   With the developments in nanotechnology, nanofibrous materials attract great attention as possible platforms for fluidic engineering. This requires an understanding of droplet interactions with fibers when gravity plays no significant role. This work aims to classify all possible axisymmetric configurations of droplets on fibers. The contact angle that the drop makes with the fiber surface is allowed to change from 0° to 180°. Nodoidal apple-like droplets with inverted menisci cusped toward the droplet center and unduloidal droplets with menisci cusped away from the droplet center were introduced and fully analyzed. The existing theory describing axisymmetric droplets on fibers is significantly enriched introducing new morphological configurations of droplets. It is experimentally shown that the barreled droplets could be formed on non-wettable fibers offering contact angles greater than 90°. The theory was quantitatively confirmed with hemispherical droplets formed at the end of a capillary tube and satisfying all the boundary conditions of the model. It is expected that the developed theory could be used for the design of nanofiber-based fluidic devices and for drop-on-demand technologies.

    

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5. Graded-index solitons in multimode fibers

   https://doi.org/10.1364/OL.43.003345  

   Ahsan, Amira S. ; Agrawal, Govind P. ( July 2018 , Optics Letters)