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Gradient-Structured Nonflammable Flexible Polymer Membranes

J. Zhu, J. Breu, H. Hou, A. Greiner, S. Agarwal

ACS Applied Materials & Interfaces 2019 11 (12), 11876-11883

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Herein, we report the formation and properties of a rare example of high-performance composite membranes from poly-bisbenzimidazobenzophenanthroline-dione (BBB) that do not sustain a flame or burn with smoke nor show melt dripping. In addition, this material possesses a low density and very high thermal stability (char yield as high as 80–94%), strength, and flexibility. Such membranes are highly desirable for battery separators, protective clothing, construction, and automobiles. Because BBB is an insoluble and infusible polymer, the composite membranes were made using a bottom-up vacuum-assisted self-assembly method with an aqueous dispersion of short BBB fibers and Hec. The use of water as the solvent, upscalability, and excellent flame retardancy in combination with low density, flexibility, and low thermal conductivity of the composite membranes make the preparation method and membranes highly promising for future use in real applications.

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New Review  by S. Agarwal, S. Jiang, Y. Chen published in Macromol. Mater.

S. Agarwal, S. Jiang, Y. Chen

Macromol. Mater. Eng., 2018, 1800548

Review_Polymer_Actuators

Welcome to Macromolecular Chemistry II

Spruch der Woche


Perfektion ist erreicht, nicht, wenn sich nichts mehr hinzufügen lässt, sondern, wenn man nichts mehr wegnehmen kann. (Antoine de Saint-Exupery) (Perfection is achieved, not when nothing more can be added, but when nothing more can be taken away (Antoine de Saint-Exupery))


"Die reinste Form des Wahnsinns ist es, alles beim Alten zu lassen und gleichzeitig zu hoffen, dass sich etwas ändert. (The sheerest madness is to leave everything the way it is and to simultaneously hope that something will change)" Albert Einstein


"The fate of genius is to be misunderstood, but not everything is a misunderstood genius" Ralp Waldo Emmerson (1803-1882)


"Facts do not cease to exist because they are ignored” (Aldous Huxley, author of Brave New World)


"Die Ablehnung Unwichtiges zu tun, ist eine entscheidende Voraussetzung für den Erfolg“ Sir Alexander MacKenzie


"An idea that is not dangerous is unworthy of being called an idea at all“ von Oscar Wilde (Eine Idee, die nicht gewagt ist, verdient es nicht, überhaupt eine Idee genannt zu werden)

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News 25.04.2019

High‐Temperature Spray‐Dried Polymer/Bacteria Microparticles for Electrospinning of Composite Nonwovens

S. Reich, P. Kaiser, M. Mafi, H. Schmalz, D. Rhinow, R. Freitag, A. Greiner

 Macromol. Biosci. 2019, 1800356.

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Living Micrococcus luteus (M. luteus) and Escherichia coli (E. coli) are encapsulated in poly(vinyl alcohol), poly(vinylpyrrolidone), hydroxypropyl cellulose, and gelatin by high‐temperature spray drying. The challenge is the survival of the bacteria during the standard spray‐drying process at temperatures of 150 °C (M. luteus) and 120 °C (E. coli). Raman imaging and transmission electron microscopy indicate encapsulated bacteria in hollow composite microparticles. The versatility of the spray‐dried polymer bacteria microparticles is successfully proved by standard polymer solution–processing techniques such as electrospinning, even with harmful solvents, to water‐insoluble polyacrylonitrile, polystyrene, poly(methyl methacrylate), and poly(vinyl butyrate) nanofiber nonwovens, which opens numerous new opportunities for novel applications.
 

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