Heat resisting and water-soluble chocolate polyesters containing azomethine group

Abstract

In this study, soluble in water poly(azomethine-ester)s (PAEs) were synthesized via elimination reactions of aromatic dihydroxy compounds containing imine bonding with terephthaloyl chloride. The structures of Schiff bases (SBs) and PAEs containing different aliphatic chains were confirmed by FT-IR, 1 H-NMR, 13 C-NMR and UV-Vis analyses. Physicochemical properties of the new polymers were characterized. Thermal properties of the compounds were investigated by TGA-DTA, DMA and DSC. According to TGA measurements, the starting degradation temperatures (T on ) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 255°C, 232°C, 222°C, and 221°C, respectively. The starting degradation temperatures of the poly(azomethine-ester)s were higher than their Schiff base compounds. According to dynamical mechanical analysis (DMA) measurements, glass transition temperature (T g ) of P-1, P-2, P-3, and P-4 poly(azomethine-ester)s were found as 95°C, 138°C, 140°C, and 145°C, respectively. The morphological and topographic properties of the PAEs containing azomethine linkage in the main chain were investigated by FE-SEM and AFM, respectively. The molecular mass distributions of PAEs were determined by gel permeation chromatography (GPC). Electrochemical (E g ) and optical band gap (E opt g ) values of the prepared SBs and PAEs were calculated from cyclic voltammetry (CV) and UV-Vis analyses. The electrochemical band gap (E g ) values of P-1, P-2, P-3 and P-4 were found as 2.44 eV, 2.41 eV, 2.39 eV and 2.39 eV, respectively, from the cyclic voltammetry.

Designed to Degrade: Tailoring Polyesters for Circularity

“…Besides the self-healing, the resulting polymer also presented UV-shielding and antifungal properties. Although still not investigated in terms of recyclability and/or biodegradability, poly­(azomethine esters) have been reported to be promising for demanding aerospace and automotive applications in light of their high thermal resistance, low band gap, and semiconductive properties. − …”

“…Chemical recycling scheme for polyester (MI75 and MI 50) and polyester-imine (SB_MI50) thermosets including images of the resulting recycled products and recured thermosets. Reproduced with permission from ref . Copyright 2023 The Authors CC-BY 4.0.…”

Synthesis and characterization of new thermally stable, antimicrobial and red-light-emitting poly(azomethine-ester)s

“…The polymers containing azomethine (CH=N) units have many attracting properties such as thermal stability [2,3], fluorescence [4][5][6], antimicrobial activities [7,8] and their use as adsorbent for the removal of heavy metal ions from water systems [8,9]. Therefore, a number of polyesters containing azomethine units also called poly(azomethineester)s have been prepared and interest in the synthesis of new poly(azomethineester)s continue because of their useful applications which include electrical conductance [10], liquid crystalline [11], corrosion inhibition [12], heat resistance [13][14][15], opto(electronic) [16], biocidal activity [17], photoluminescence [18] and fiber-forming ability [19]. However, the processing of aromatic poly(azomethineester)s is difficult because of their high melting temperatures and their limited solubility in common organic solvents [20,21].…”