We describe herein the state of the art following the last 8 years of research into aromatic polyamides, wholly aromatic polyamides or aramids. These polymers belong to the family of high performance materials because of their exceptional thermal and mechanical behavior. Commercially, they have been transformed into fibers mainly for production of advanced composites, paper, and cut and fire protective garments. Huge research efforts have been carried out to take advantage of the mentioned characteristics in advanced fields related to transport applications, optically active materials, electroactive materials, smart materials, or materials with even better mechanical and thermal behavior.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6419023 | PMC |
http://dx.doi.org/10.3390/polym9090414 | DOI Listing |
Polymers (Basel)
January 2025
Centro de Nanotecnología Aplicada, Facultad de Ciencias, Ingeniería y Tecnología, Universidad Mayor, Camino La Pirámide 5750, Huechuraba 8580745, Chile.
This study explores the development and evaluation of a novel series of aromatic co-polyamides featuring diverse pendant groups, including phenyl and pyridinyl derivatives, designed for water desalination membrane applications. These co-polyamides, synthesized with a combination of hexafluoroisopropyl, oxyether, phenyl, and amide groups, exhibited excellent solubility in polar aprotic solvents, thermal stability exceeding 350 °C, and the ability to form robust, flexible films. Membranes prepared via phase inversion demonstrated variable water permeability and NaCl rejection rates, significantly influenced by the pendant group chemistry.
View Article and Find Full Text PDFMembranes (Basel)
January 2025
Saint-Petersburg State Institute of Technology, Technical University, 190013 Saint Petersburg, Russia.
New aromatic co-polyamide-imides (coPAIs) containing both carboxyl and hydroxyl groups in the repeating units were synthesized for the first time. Transport, thermal and morphological properties of dense nonporous membranes from PAIs obtained using the diacid chloride of 2-(4-carboxyphenyl)-1,3-dioxoisoindoline-5-carboxylic acid and diamines 5,5'-methylene-bis (2-aminophenol)) and 3,5-Diaminobenzoic acid, taken in molar ratios of 7:3, 1:1, and 3:7, have been studied. High levels of membrane permeability accompanied by high selectivity for mixtures of liquids with significantly different polarities were determined by realization of intra- and intermolecular interactions in polymer, which was proved by thermal analyses and hydrodynamic characteristics of coPAIs.
View Article and Find Full Text PDFSci Rep
January 2025
Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, 16846-13114, Tehran, Iran.
Water Res
December 2024
Department of Civil Engineering, University of Hong Kong, Pokfulam, Hong Kong, PR China.
The kinetics of polyamide membrane degradation by free chlorine and halide ions (Br and Cl) were innovatively evaluated based on physicochemical properties and filtration performance, using water/solute permeability coefficient in addition to bromide incorporation as important indicators. The reaction rate constants for the reduced water and HBO permeability coefficient were 1-2 orders of magnitude higher at 0-1 h than 1-10 h. N-bromination and bromination-promoted hydrolysis are dominant degradation mechanisms at 0-1 h (reflected by the breakage of hydrogen bond, the increased Ca binding content, and the increased charge density), and ring-bromination further occurs at 1-10 h (reflected by the disappearance or weakening of aromatic amide band and the nearly constant hydrogen bond).
View Article and Find Full Text PDFEnviron Pollut
February 2025
Hebei Key Laboratory of Close-to-Nature Restoration Technology of Wetlands, School of Eco-Environment, Hebei University, Baoding, 071002, PR China. Electronic address:
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!