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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. Fully recyclable carbon nanotube fibers

   https://doi.org/10.1016/j.carbon.2024.119899  

   Siqueira, Ivan R; Durán-Chaves, Michelle; Dewey, Oliver S; Williams, Steven M; Ginestra, Cedric JS; De_La_Garza, Juan; Song, Yingru; Wehmeyer, Geoff; Pasquali, Matteo (February 2025, Carbon)
3. 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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4. Optimized SVM constellations for SDM fibers

   Fink, Eric; Kwapisz, Jaroslaw; Roudas, Ioannis (October 2021, IEEE Photonics Conference)

   null (Ed.)

   Stokes vector modulation (SVM) can be used together with multimode and multicore fibers. We study various algorithms for optimal geometric constellation shaping and bit-to-symbol mapping in the generalized Stokesspace. We evaluate the performance of these constellations for optically-preamplified direct-detection receivers. 

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5. Thermoresponsive Conductivity of Graphene‐Based Fibers

   https://doi.org/10.1002/smll.202204981  

   Salim, Muhammad G.; Vasudevan, Vaibhav; Schulman, Nicholas; Zamani, Somayeh; Kersey, Kyle D.; Joshi, Yash; AlAmer, Mohammed; Choi, Ji Il; Jang, Seung Soon; Joo, Yong Lak (February 2023, Small)

   Abstract Smart materials are versatile material systems which exhibit a measurable response to external stimuli. Recently, smart material systems have been developed which incorporate graphene in order to share on its various advantageous properties, such as mechanical strength, electrical conductivity, and thermal conductivity as well as to achieve unique stimuli‐dependent responses. Here, a graphene fiber‐based smart material that exhibits reversible electrical conductivity switching at a relatively low temperature (60 °C), is reported. Using molecular dynamics (MD) simulation and density functional theory‐based non‐equilibrium Green's function (DFT‐NEGF) approach, it is revealed that this thermo‐response behavior is due to the change in configuration of amphiphilic triblock dispersant molecules occurring in the graphene fiber during heating or cooling. These conformational changes alter the total number of graphene‐graphene contacts within the composite material system, and thus the electrical conductivity as well. Additionally, this graphene fiber fabrication approach uses a scalable, facile, water‐based method, that makes it easy to modify material composition ratios. In all, this work represents an important step forward to enable complete functional tuning of graphene‐based smart materials at the nanoscale while increasing commercialization viability. 

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