Aqueously soluble semi‐aromatic copolyamides with dual‐functional groups as sizing agent

Abstract

A series of novel aqueously soluble semi-aromatic (co)polyamides, poly[(ethylenedioxy)bis(ethylene) terephthalamide]-ranpoly[(ethylenedioxy)bis(ethylene) (2,5-dihydroxy-3,6-diallyl)terephthalamide] (CRPAOT-x), were prepared via the solid-state Claisen rearrangement reaction of poly[(ethylenedioxy)bis(ethylene) terephthalamide]-ran-poly[(ethylenedioxy)bis(ethylene) 2,5-bis(allyloxy)terephthalamide] (APAOT-x), where x (= 0, 13, 25, 50, 75, and 100) represents the molar fraction of allyloxy containing unit. APAOT-x was obtained through the interfacial copolymerization of terephthaloyl chloride, 2,5-bis(allyloxy)terephthaloyl chloride, and 2,2 0 -(ethylenedioxy)bis(ethylamine). The reaction conditions including reactant concentration, temperature, and solvent were optimized. The chemical structures of the target (co)polyamides and their precursors were characterized by proton nuclear magnetic resonance ( 1 H NMR) and Fourier transform infrared spectroscopies. The incorporation of hydrophilic (ethylenedioxy)bis(ethylene) units greatly improved the polymer solubility. CRPAOT-x dissolved not only in polar organic solvents such as dimethylformamide, dimethyl sulfoxide, and N-methyl pyrrolidone but also in ammonia water. Due to the presence of hydroxyl groups and oxygen-rich aliphatic units, CRPAOT-x showed excellent affinity toward epoxy resins. The microbond test indicated that the aramid fibers sized by these dual-functional polymers exhibited remarkably enhanced interfacial shear strength in epoxy matrices.

Research Progress of Semi-Aromatic Copolyamides: Structure-Property Relationship

“…13C-NMR and 15N-NMR can distinguish the mixture of homopolyamides, and the different sequence structure of copolyamides. However, due to the occurrence of chain exchange and chain transfer in the polycondensation process, the synthesized copolyamides commonly contain random chain segments, and the poor solubility of the copolyamides result in the unclear NMR peak [9,10].…”

Semi-Aromatic Polyether Amide Thermoplastic Elastomer: Nucleophilic Substitution Polymerization and Properties

“…Tong and co-workers synthesized a series of TPAEs based on semi-aromatic polyamide PA10T/10I through two-step melt polycondensation. Qi and co-workers prepared a series of novel aqueously soluble semi-aromatic (co)­polyamides by double bonds introduced into the branched chain, which endowed the copolymers with great processability. Therefore, semi-aromatic polyamides were a great choice for the hard segments of TPEs on account of their physical and processing performance .…”

Direct Synthesis of Thermally Stable Semiaromatic Polyamides by Bulk Polymerization Using Aromatic Diamines and Aliphatic Dicarboxylic Acids

“…Looking at a synthetic method, polyamides are generally synthesized by solution polymerization. However, this method has disadvantages in terms of environmental friendliness, i.e., the use of acid chlorides as monomers to eliminate many salts after polymerization and the use of organic solvents. ,− Thus, the development of a simpler and more environmentally friendly polymerization method is required. To synthesize a semiaromatic polyamide in an environmentally friendly manner, there are two direct bulk polymerization strategies: (a) direct polymerization between an aliphatic diamine and aromatic dicarboxylic acid and (b) direct polymerization between an aromatic diamine and aliphatic dicarboxylic acid.…”