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Four photochromic spiropyran‐amylose (ASP) biobased polymers with different spiropyran (SP) grafting density, DS, ASP10 (DS = 0.12), ASP40 and ASP40PA60 (DS = 0.40), and ASP100 (DS = 0.97), are synthesized through azide‐alkyne cycloaddition of an alkynyl‐functional SP derivative onto C6‐azidated‐amylose (AN3), where the unconverted azide in ASP40PA60, ASP100, and the AN3 precursor are quenched by clicking with propargyl alcohol (PA). All ASPs are poorly soluble in trifluoroethanol, ethanol, and water but soluble in dimethyl sulfoxide, N,N‐dimethylformamide, and hexafluoroisopropanol irrespective of UV irradiation, switching reversibly the grafted SP into zwitterionic merocyanine (MC). Only ASP10 and ASP40 are slightly soluble in the low polarity tetrahydrofuran, with ASP40 showing a marked photochromism and reduction of solubility on SP→MC switching. The photochromism in solution is preserved in the solid state, although with significant differences between the still relatively fast SP→MC photoisomerization and the much slower thermal retro‐isomerization. The dynamics of both processes, evaluated in a thin spin–coated ASP100 film and a thicker ASP40 photoswitchable coating on glass and paper, is more clearly affected than in solution by the grafting density. Switching the nearly apolar SP into the zwitterionic MC does not significantly affect wettability of the slightly hydrophobic ASP40 coating. [ABSTRACT FROM AUTHOR]

A flexible microporous polymer paper (MPP) is prepared with the polymer tubes obtained from the Sonogashira coupling reaction of 1,4-diiodotetrafluorobenzene and 1,3,5-triethynylbenzene. MPP has an interconnected network structure of polymer tubes and shows a hierarchical pore structure. Relatively large pores are formed among entangled polymer tubes, while micro- and mesopores are generated in the tube walls. MPP is foldable, mechanically stable, and stretchable. When the folding stress is removed, a wrinkle forms along the folded line, as observed in common papers composed of cellulose pulps. The mechanical stability of MPP results from electrostatic interactions between electron deficient tetrafluorobenzene units and electron rich triethynylbenzene units in the polymer. The tensile stress-tensile strain curve shows that MPP can elongate up to 15% strain. MPP is superhydrophobic, showing a water contact angle of 162° and can be used for the filtration of small molecules such as a dye and iodine. [ABSTRACT FROM AUTHOR]

In this study, the successful transfer of chemical vapor deposition (CVD)‐grown graphene on an ordinary printing paper surface is demonstrated. Pristine paper is not a suitable substrate for graphene transfer because of its fragile and hydrophilic nature against the chemicals used during the transfer process. Two different fluoroalkyl polymers, namely poly(hexafluorobutyl acrylate) (PHFBA) and poly(perfluorodecyl acrylate) (PPFDA) are coated on paper surfaces by an initiated CVD (iCVD) technique to make the paper surfaces hydrophobic. Hydrophobicity is found to be an important factor in order for the graphene to be transferred onto the paper substrate. Although surfaces coated with PPFDA possess better hydrophobicity owing to their longer perfluoroalkyl group and higher roughness, the graphene transfer is found to be more successful on a PHFBA‐coated surface. A thin film of PHFBA on the paper surface acts as a prime layer for effective and defect‐free transfer of graphene and makes the paper surface ideal and robust during the graphene transfer process. The as‐transferred graphene layer on the PHFBA‐coated paper surface shows high conductivity values, even after repeated folding and flattening cycles. [ABSTRACT FROM AUTHOR]