Covalent organic nanosheets (CONs) are a new class of porous thin two-dimensional (2D) nanostructures that can be easily designed and functionalized and could be useful for separation applications. Poor dispersion, layer restacking, and difficult postsynthetic modifications are the major hurdles that need to be overcome to fabricate scalable CON thin films. Herein, we present a unique approach for the chemical exfoliation of an anthracene-based covalent organic framework (COF) to N-hexylmaleimide-functionalized CONs, to yield centimeter-sized free-standing thin films through layer-by-layer CON assembly at the air-water interface. The thin-layer fabrication technique presented here is simple, scalable, and does not require any surfactants or stabilizing agents.

Covalent organic nanosheets (CONs) are a new class of porous thin two‐dimensional (2D) nanostructures that can be easily designed and functionalized and could be useful for separation applications. Poor dispersion, layer restacking, and difficult postsynthetic modifications are the major hurdles that need to be overcome to fabricate scalable CON thin films. Herein, we present a unique approach for the chemical exfoliation of an anthracene‐based covalent organic framework (COF) to N‐hexylmaleimide‐functionalized CONs, to yield centimeter‐sized free‐standing thin films through layer‐by‐layer CON assembly at the air–water interface. The thin‐layer fabrication technique presented here is simple, scalable, and does not require any surfactants or stabilizing agents.

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We continue to investigate the design, synthesis, and characterization of electrically and ionically active conjugated polythiophene copolymers for integrating a variety of biomedical devices with living tissue. This paper will describe some of our most recent results, including the development of several new monomers that can tailor the surface chemistry, adhesion, and biointegration of these materials with neural cells. Our efforts have focused on copolymers of 3,4 ethylenedioxythiophene (EDOT), functionalized variants of EDOT (including EDOT-acid and the trifunctional EPh), and dopamine (DOPA). The resulting PEDOT-based copolymers have electrical, optical, mechanical, and adhesive properties that can be precisely tailored by fine tuning the chemical composition and structure. Here we present results on EDOT-dopamine bifunctional monomers and their corresponding polymers. We discuss the design and synthesis of an EDOT-cholesterol that combines the thiophene with a biological moiety known to exhibit surface-active behaviour. We will also introduce EDOT-aldehyde and EDOT-maleimide monomers and show how they can be used as the starting point for a wide variety of functionalized monomers and polymers.

A series of new bio‐based aromatic diisocyanates, namely bis(4‐isocyanato‐2‐methoxyphenoxy)alkane and bis(4‐isocyanato‐2,6‐dimethoxyphenoxy)alkane, were synthesized starting from lignin‐derived phenolic acids, namely vanillic acid and syringic acid, via the Curtius rearrangement. The diisocyanates were employed to synthesize poly(ether urethane)s by reacting them with potentially bio‐based aliphatic diols, namely 1,10‐decanediol and 1,12‐dodecanediol. The chemical structures of diisocyanates and poly(ether urethane)s were confirmed using Fourier transform infrared, 1H NMR and 13C NMR spectroscopy. Inherent viscosities and number‐average molecular weights of the poly(ether urethane)s were in the ranges 0.58–0.68 dL g−1 and 32 100–58 500 g mol−1, respectively, indicating the formation of reasonably high molecular weight polymers. The poly(ether urethane)s exhibited 10% weight loss in the temperature range 304–308 °C. The glass transition temperatures of the poly(ether urethane)s were in the range 49–74 °C and were dependent both on the number of methylene units in the diols and on the number of methoxy substituents on the aromatic rings of the diisocyanate component. © 2017 Society of Chemical Industry

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A fully bio-based bisphenol, namely, 4,4′-(furan-2-ylmethylene)bis(2-methoxyphenol) was synthesized and its utility for synthesis of aromatic poly(ether sulfone)s bearing clickable pendant furyl groups was demonstrated.