POSS‐based fluorinated azobenzene‐containing polymers: Photo‐responsive behavior and evaluation of water repellency

Abstract

The photoresponsive polyhedral oligomeric silsesquioxanes (POSS) based fluorinated azobenzene‐containing polymers were prepared and characterized by NMR, FT‐IR, GPC, XRD, TG and UV–Vis spectra. The thermal property of the polymers was improved by the introduction of POSS cage. The trans‐cis photoisomerization of the polymers in solution was similar to that of the fluorinated azobenzene monomer and in accordance with the first‐order reaction kinetics equation within the first 250 seconds UV irradiation. The cotton fabrics coated with the polymers showed excellent water repellency and possessed switchable wettability under UV irradiation. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43540.

Switchable and Reversible Superhydrophobic Surfaces: Part One

“…Organic chemicals containing photochromic functional groups such as azobenzenes [115], diarylethenes, spiropyrans [116], bipyridyl ethylenes [117], stilbenes [118] or pyrimidines [119] can follow a reversible transition by UV/vis light, which can lead to differences of wettability. Among them, azobenzene group and its derivatives are extremely promising as photosensitive materials and were highly studied in the literature [120][121][122][123][124][125][126][127][128][129][130][131][132][133][134][135]. The azobenzene group is able to reversely switch from the trans to the cis isomer by UV light and visible light irradiation, as shown in Figure 8 [121].…”

“…Other works showed the possibility to modify cotton and paper substrates with these kinds of photosensitive polymers [127][128][129]. Using polyhedral oligomeric silsesquioxane (POSS) and fluorinated azobenzene, Gao et al reported the possibility to obtain cotton fabrics with switchable from superhydrophobic/superoleophobic to highly hydrophobic/oleophobic [128,129]. Indeed, many works were dedicated to the switching from superhydrophobic (low adhesion) to parahydrophobic (high adhesion) after UV irradiation.…”

Liquid crystallinity and thermal properties of polyhedral oligomeric silsesquioxane/side-chain azobenzene hybrid copolymer

“…The structure and performance characteristics of azobenzene were studied deeply [28][29][30][31][32]. Chen et al [33] prepared the functional POSS-based fluorinated azobenzene polymers, which were expected to be applied on the surface with light-responsive properties with controlled wettability. Miniewicz et al [34] reported a novel polymer of polymethyl methacrylate composite dispersed with azo-functionalized POSS nanoparticles with photoresponsive properties.…”