Aromatic Polyamides Containing Pendent Acetoxybenzamide Groups

Abstract

Summary: Polycondensation reaction of 5-(4-acetoxy-benzamide) isophthaloylchloride with different aromatic diamines gave a series of polyisophthalamides with good solubility in organic solvents. These polymers showed good thermal stability with initial decomposition temperature above 300 8C and glass transition temperature in the range of 220-335 8C. Thin, flexible, transparent films were cast from solutions, having good electroinsulating properties.

Synthesis and characterization of new thermally stable and organosoluble polyamides by direct polycondensation

“…Techniques 1 H and 13 C NMR spectra were recorded on a Bruker 300 MHz instrument (Germany) and with a Bruker Avance III 500 spectrometer (Rheinstetten, Germany) operating at 500 MHz ( 1 H). The DMSO-d 6 was used as the solvent and the solvent signal was used for internal calibration (DMSO-d 6 : δ( 1 H) = 2.5 ppm).…”

“…A broad singlet peak at 12.1 ppm was related to carboxylic acid protons (Figure 3). Also, the 13 C NMR spectrum of dicarboxylic acid 9 showed nine different carbon atoms (Figure 4). …”

“…The introduction of flexible chains into the polyamide backbone [3], synthesis of PAs with noncoplaner unit in the polymer chains [4], preparation of copolymers such as poly(amide-imide)s [5][6][7][8], poly (ester-imide)s [9], and poly(amide-ester-imide)s, [10] and the introduction of bulky side groups into the polymer chains [11][12][13] resulted in a series of modified PAs.…”

Preparation of New Optically Active Polyamides Containing a L-Phenylalanine, Phthalimide Side-Chain via the Diisocyanate Route by Microwave Energy: Comparison With Conventional Heating

“…PAs are used to engineer semi-crystalline thermoplastics which have been broadly employed in food packaging applications due to their mechanical and chemical resistance, good barrier properties to gases, transparency and printability [7][8][9]. However, they are generally inflexible due to their high melting or softening temperatures and their limited solubility in organic solvents [10][11][12][13][14][15]. Many efforts to increase the solubility of aromatic PAs have been made through the introduction of flexible groups into the main, as well as the side-chain of polymers or by the replacement of symmetrical aromatic rings by unsymmetrical ones; this leads to a decrease in the crystallinity.…”

Room Temperature Ionic Liquids as Replacements for Organic Solvents: Direct Preparation of Wholly Aromatic Polyamides Containing Phthalimide and S-valine Moieties

“…These modifications work by breaking the chain symmetry and regularity and by destroying hydrogen bonds and generally lead to lower transition temperatures and better solubility. [28][29][30][31][32] In many cases, the introduction of diverse heterocyclic rings into the chains of polyamides led to polymers with improved solubility and enhanced thermal stability. [32][33][34][35] In the history of polymer science, both naturally occurring and synthetic optically active polymers (OAP)s have received much attention in conjunction with their stereochemistry, and extensive studies have been conducted on their syntheses, conformations and functions.…”