Abstract
New materials based on methacrylic polymers modified with 1-(4-nitrophenyl)piperazine side chains, differing in the distance of the chromophore from the polymer main chain and/or the separation between the chromophoric units in the chain, are obtained and characterized in terms of their potential applications in optoelectronic devices. The surface, structural, and optical properties of the investigated materials are determined using atomic force microscopy, spectroscopic ellipsometry combined with transmission measurements, Raman and Fourier transform infrared spectroscopy, as well as cyclic voltammetry. The relevant model systems are additionally analyzed with quantum chemical density functional theory calculations in order to enable the generalization of the structure–photophysical property relationships for the optimization of the material features. It is found that the structural modification of the material, relying on the transit of the piperazine moiety away from the main polymer chain, leads to the hypsochromic shift of the absorption spectrum. Moreover, the lowest refractive index values are obtained for the polymer with a distant ethylene group in the side-chains and increased separation between the piperazine units. It was shown that the optical energy band gaps of the investigated piperazine-containing polymers are in the range from 2.73 to 2.81 eV, which reveals their promising potential for the advances in photovoltaics, field effect transistors, or electrochromic devices as an alternative for other widely applied polymer materials.
Highlights
In recent years, organic optoelectronic materials have been receiving much scientific attention due to their low production costs and possible rational design and precise tailoring of their properties through modifications of their chemical structure.[1]
Their structures were confirmed by 1H nuclear magnetic resonance (NMR) spectra and an accordance was observed between the observed n/m values in the polymers and the respective amounts of the introduced monomer ratios
The surface, structural, and optical properties of the analyzed materials change with the increase of the chromophore distance from the polymer main chain by adding an ethylene group and with the growth of the separation between the chromophoric units in the polymer
Summary
Organic optoelectronic materials have been receiving much scientific attention due to their low production costs and possible rational design and precise tailoring of their properties through modifications of their chemical structure.[1] Among them, an important class of materials are donor−πconjugated bridge−acceptor (D−π−A) systems, which are attractive for applications such as nonlinear optical devices, organic light-emitting diodes, and organic solar cells (OSCs) because of the intermolecular charge transfer character of their excited state.[2] the molecular properties of these “push−pull” systems depend on the ability of the donor groups to provide electrons and acceptor groups to withdraw them. Its glasstransition temperature ranges broadly from approximately 87 to 157 °C.6 Due to these properties, PMMA is used for the preparation of the transparent gel electrolyte in solid-state electrochromic devices.[7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
