Synthesis and characterization of novel aromatic polyamides via Yamazaki–Higashi phosphorylation method

Abstract

We synthesized four aromatic diacids: 1,3‐bis(3‐carboxyphenoxy)benzene, 1,4‐bis(4‐carboxyphenoxy)benzene, 1,4‐bis(3‐carboxyphenoxy) benzene, and 1,3‐bis(4‐carboxyphenoxy)benzene, following a procedure of a previously reported synthesis (Ueda and Komatsu, J Polym Sci Part A: Polym Chem 1989, 27, 1017). These diacids were condensed directly with aromatic diamines 4,4′‐oxydianiline (ODA), via the Yamazaki–Higashi phosphorylation method in the presence of triphenylphosphite (TPP), pyridine (Py) and halide salts to give high molecular aromatic polyamides (PAs). The synthesized PAs were obtained in quantitative yields with inherent viscosities between 0.5 and 1.0 dL g−1. The structures and properties of the obtained PAs were characterized by Fourier transform infrared (FTIR) spectra, nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), polarizing optical microscope (POM). Four PAs all showed good solubility in polar solvents, such as dimethylsulfoxide (DMSO), N,N‐dimethylacetamide (DMAc), N‐dimethylformamide (DMF), 1‐methylpyrrolidone (NMP), and so on. The obtained polymers showed high thermal stability with decomposition temperature around 400°C. The polyamide membranes manifest excellent mechanical properties, with Young's modulus of 2.5–5.5 GPa. Interestingly, the film of PA‐1, PA‐2, and PA‐3 is completely transparent in the visible range, while PA‐4 film is opaque. Crystallization was observed in PA‐4 film, although the molecular structure of PA‐4 is not as symmetrical as PA‐2. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Structural manipulation of PES constituents to prepare advanced alternative polymer for ultrafiltration membrane

“…PES with MW 58000 g/mol was obtained from BASF Company, Germany. N ‐methyl‐2‐pyrrolidone (NMP, Merck) before use was dried at 130 °C under vacuum over calcium hydride …”

“…N-methyl-2-pyrrolidone (NMP, Merck) before use was dried at 130 C under vacuum over calcium hydride. 32…”

Synthesis and characterization of novel functional hyperbranched polyamides from AB2 units: effect of extra functional groups

“…To prepare all hyperbranched structures, the Yamazaki method was employed [23]. A mixture of 10 mmol of AB 2 monomers, 3 mL of NMP, 2 g of lithium chloride, 3 mL of TPP and 2 mL of pyridine was refluxed for 6 h at 120°C (Figure 3).…”

Functional Aromatic Polyamides

“…Zhao [143] described dicarboxylic acids containing flexible linkages, as a way of improving the solubility of the derived aromatic polyamide (Scheme 31, P55). The polymers showed good solubility in polar aprotic solvents, and high thermal stability with decomposition temperatures around 400 • C. Membranes out of these polyamides manifest excellent mechanical properties, with Young's modulus of 2.5-5.5 GPa.…”