Preparation of photoactive ZnS-composite porous polymer films: Fluorescent and morphological properties

Abstract

This work describes the use of the breath figure (BF) method for the fabrication of photoactive porous polymer films and the characterization of their responsive to photo stimulus. The films incorporate self-assembled photoactive polymers and ZnS nanoparticles (NPs). The effect of both components on the optical and morphological properties of the films were analyzed. Films with a hexagonally ordered pattern were obtained. The photoactive polymer was prepared by grafting the photochromic component 1-(2-hydroxyethyl)-3,3-dimethylindoline-6-nitrobenzopyran (SP) to polystyrene-block-polymethacrylic acid (PS-b-PMMA). ZnS NPs were incorporated into the polymer solution, and the films were prepared using spin-coating on glass substrates before subjecting them to the BF method. The hollow footprints were obtained before introducing the ZnS NPs in order to maintain the necessary conditions for hexagonal film growth. Accordingly, the SEM micrographs of the films prepared in the presence of ZnS NPs displayed a loss in the pore arrangement as a consequence of the interaction between SP moiety and NPs. The lightemitting properties of films were characterized by blue and violet colors when exposed to UV light under fluorescence. Progress in the field of breath-figure formation and its application, such as exemplified in this work, leads to functional structures with suitable applications in chemistry and materials science. It is expected that such microstructured polymeric films will have interesting applications in photonic and optoelectronic devices.

Design and Study of a Photo-Switchable Polymeric System in the Presence of ZnS Nanoparticles under the Influence of UV Light Irradiation

“…The resulting block copolymer was obtained as a white powder (yield: 85%). The process above is described in more detail elsewhere [ 66 , 67 ]. The FT-IR spectrum exhibited characteristic absorption bands at 3066–3026 cm −1 [υ(CH, aromatic)]; 2923–2852 cm −1 [υ(CH, CH 2 )]; 1948–1875 cm −1 [υ(aromatic overtone)]; 1650.34 cm −1 [υ(–C=O from MMA)]; 758.31 and 691.26 cm −1 [υ(aromatic ring)].…”

“…The resulting block copolymer was obtained as a white powder (yield: 85%). The process above is described in more detail elsewhere [66,67]. The FT-IR spectrum exhibited characteristic absorption bands at 3066-3026 cm In a first step, the synthesis of the 1-(2-hydroxyethyl)-2,3,3-trimethylindolenine bromide was carried out in a schlenk tube in which 4.0 mL (3968 mg, 25 mmol) of 2,3,3trimethylindolenine were added, then 1.8 mL (3173 mg, 25 mmol) of 2-bromoethanol in 3.15 mL (2536 mg, 35 mmol) of 2-butanone was used as solvent.…”