Synthesis of novel nanostructured chiral poly(amide-imide)s containing dopamine and natural amino acids

Abstract

Four new thermally stable and optically active poly(amide-imide)s (PAI)s with good inherent viscosities were synthesized from the direct polycondensation reaction of N,N-(pyromellitoyl)-bis-L-α-amino acids with 3,5-diamino-N-(3,4-dihydroxy-phen-ethyl)benzamide in a medium consisting of a molten salt, tetrabutylammonium bromide, and triphenyl phosphite as the activator. The polymerization reactions produced a series of novel PAIs containing dopamine segment in the side chain in high yield with inherent viscosities between 0.33 and 0.49 dL/g. The obtained polymers were typically characterized by means of FT-IR, 1 H NMR spectroscopy, elemental analyses, powder X-ray diffraction, field emission scanning electron microscopy, inherent viscosity, and solubility tests. Thermal properties and flame retardant behaviour of the PAIs were also investigated using thermal gravimetric analysis (TGA and DTG) and limiting oxygen index (LOI). Data obtained by thermal analysis revealed that these polymers showed good thermal stability. Furthermore, high char yield in TGA and good LOI values indicated that the obtained polymers were capable of exhibiting good flame retardant properties.

Efficient functionalization of multi‐walled carbon nanotubes with p‐aminophenol and their application in the fabrication of poly(amide‐imide)‐matrix composites

“…The effect of adding CNTs on the thermal, physical and mechanical properties of poly(amide‐imide)s (PAIs) has been studied by many groups, but few studies have been concerned with the fabrication of multi‐walled CNT (MWCNT)/PAI composites –. The purpose of the work reported here was to study a rapid and simple functionalization of MWCNTs with p ‐aminophenol ( p ‐AP) under microwave irradiation.…”

Antimicrobial, mechanical, optical and thermal properties of PVC/ZnO‐EDTA nanocomposite films

“…LOI value for PVC/ZnO‐EDTA NCs is calculated and compared with neat PVC; more contents of modified ZnO increase the LOI and the char yield. Also, according to Johnson, the ΔH values of many common materials can be reasonably predicted by the relationship between the LOI and heat of combustion: ΔH comb is the energy liberated as heat when a compound undergoes complete combustion with oxygen under standard conditions in J/g . Accordingly, the amount of ΔH comb estimated is shown also in Table .…”

“…ΔH comb is the energy liberated as heat when a compound undergoes complete combustion with oxygen under standard conditions in J/g. [48] Accordingly, the amount of ΔH comb estimated is shown also in Table 2.…”

Studies of Formation Mechanism, Structure, and Properties of Network Copolymers Obtained by Cocuring of Rolivsan Thermosetting Resins with Aromatic Diamines

“…They are associated with carbonyl fragments formed after intramolecular cyclization of neighboring methacrylic units in the ROL copolymer chains. The [8][9][10][11][12][13][14]. However, it should be noted that the bands at 1780 and 727 сm -1 (typical of imide absorbance) were not observed in the spectra of the studied blend samples.…”