A novel sulfonated aromatic polyimide synthesis and characterization: Energy calculations, QTAIM simulation study of the hydrated structure of one unit

Abstract

A new type of sulfonated polyimide was synthesized from a one‐step polycondensation reaction with perylene‐3,4,9,10‐tetracarboxylic dianhydride and 4,4′‐diamino‐2,2′‐stilbenedisulfonic. Pure characterization of sulfonated polyimide (SPI) was performed by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance, thermogravimetric analysis, differential thermal gravimetric analysis, ultraviolet–visible spectroscopy, and solubility tests. Moreover, the SPI film was prepared by a thermal imidization step heating procedure. Furthermore, quantum chemical calculations of the synthesized SPI were investigated with density functional theory (DFT) and time‐dependent density functional theory. By calculating the frontiers molecular orbital energies of the obtained polyimide, the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO), and the energy gap (Δ) values were found for the one structural unit and three structural units of SPI, respectively. Also, QTAIM was carried out based on the AIMAll program. With the increase in water molecules, the average electronic energy density (HBCP) value decreased according to the results of QTAIM. The SPI can be used as a potential membrane in fuel cells.

Synthesis of Axial Bis(benzo[d][1,3]dioxol‐5‐ylmethoxy)phthalocyaninato Silicon (IV): Photophysical and Photochemical Properties and Docking Studies on DNA‐SiPc Interactions

“…It is visualized based on the energy interaction between a positive unit and electrons. Molecular electrostatic potential (MEP) is increasingly useful in evaluating the potential electrophilic and nucleophilic attacks of the molecule, as well as the positions of hydrogen‐bond interactions [40–41] . In order to map sensitive reactive sites in the Si−Pc molecule structure, SDD was measured in optimized geometry in the DFT/B3PW91 method.…”

“…Molecular electrostatic potential (MEP) is increasingly useful in evaluating the potential electrophilic and nucleophilic attacks of the molecule, as well as the positions of hydrogenbond interactions. [40][41] In order to map sensitive reactive sites in the SiÀ Pc molecule structure, SDD was measured in optimized geometry in the DFT/B3PW91 method. The negative (red) regions of MEP corresponding to Figure 7 represent electrophilic reactivity, while the positive (blue) regions are related to nucleophilic reactivity.…”

Redox-active polyimides for energy conversion and storage: from synthesis to application

“…5). 39,40 However, there is a limitation in fabricating aromatic PIs through solution-processing due to strong interactions between the polymer chains. In this Fig.…”

“…5). 39,40 However, there is a limitation in fabricating aromatic PIs through solution-processing due to strong interactions between the polymer chains. In this context, various approaches have been suggested to overcome this issue, including introducing flexible linkages or aliphatic units in the polymer backbone, 41–43 introducing side groups to hinder molecular packing and crystallization 44–46 and introducing asymmetric monomers to suppress coplanar structures.…”

Synthesis of axially silicon phthalocyanine substituted with bis- (3,4-dimethoxyphenethoxy) groups and energy features, charge density analysis and molecular docking studies

“…In QTAIM data, electron density not only characterizes the bond/interaction structure, but also classi es chemical bond/ interaction ways and distinguishes bond/ interaction strengths. [43,44] If ρ(r) > 0.1, ∇ 2 ρ(r) < 0 and H(r) < 0 (a.u. ), it is known as a typical covalent bond.…”