Synthesis and characterization of new flame‐retardant poly(amide‐imide)s containing phosphine oxide and hydantoin moieties in the main chain

Abstract

Six new flame-retardant poly(amide-imide)s (PAIs) 9a-f with high inherent viscosities containing phosphine oxide and hydantoin moieties in main chain were synthesized from the polycondensation reaction of N,N 0 -(3,3 0 -diphenylphenylphosphine oxide) bistrimellitimide diacid chloride 7 with six hydantoin derivatives 8a-f by two different methods such as solution and microwave assisted polycondensation. Results showed that the microwave assisted polycondensation, by using a domestic microwave oven, proceeded rapidly, compared with solution polycondensation, and was completed in about 7-9 min. All of the obtained polymers were fully characterized by means of elemental analysis, viscosity measurements, solubility test, and FTIR spectroscopy. Thermal properties and flame retardant behavior of the PAIs 9a-f were investigated using thermal gravimetric analysis (TGA and DTG) and limited Oxygen index (LOI). Data obtained by thermal analysis (TGA and DTG) revealed that these polymers showed good thermal stability. Furthermore, high char yields in TGA and good LOI values indicated that these polymers are capable of exhibiting good flame retardant properties. These polymers can be potentially utilized in flame retardant thermoplastic materials.

Synthesis and Characterization of Novel Alkyl-Substituted Aryl Diphenylphosphinate Esters

“…These data are in good agreement with the literature. 21,[27][28][29][30][31] In the FTIR spectra of compounds 3-12, CH (aryl) and CH (aliphatic) stretching bands are observed between 3049-3437 and 2903-2984 cm −1 , respectively.…”

Recent Advances in Microwave-Assisted Polymer Synthesis

“…Similar results were found for the MW-assisted polycondensation of different N,N -(4,4 -oxydiphthaloyl)-bis(amino acid chloride)s with aromatic amines, [99][100][101][102][103] of different N,N -(4,4 -hexafluoroisopropylidenediphthaloyl)-bis(amino acid chloride)s with aromatic amines, [104,105] of N,N -(4,4 -diphenylether)-bis(trimellitimide acid chlorides)s with hydantoin derivatives, [106] of N,N -(4,4 -sulfonediphthaloyl)-bis(amino acid chloride)s with aromatic amines [107,108] as well of epiclon-based diamino acid chlorides with aromatic amines. [109][110][111][112] The corresponding conversion of N,N -(3,3 -triphenylphosphine oxide)-bis(trimellitimide acid chloride) with different aromatic amines [113] and hydantoin derivatives [114] yielded poly(amide-imide)s with flame retardant properties. Mallakapour and Rafiemanzelat presented the MW-assisted conversion of N-trimellitylimido-l-valine [115] and bis(p-amido benzoic acid)-N-trimellitylimido-l-leucine [116] with aliphatic and aromatic diisocyanates to yield optically active poly(amide-imide)s. The influence of different solvents and MW irradiation time on polymer yield was studied.…”

Novel Flame‐Retardant and Thermally Stable Poly(Amide‐imide)s Based on Bicyclo[2,2,2]oct‐7‐Ene‐2,3,5,6‐Tetracarboxylic Diimide and Phosphine Oxide in the Main Chain: Synthesis and Characterization

“…According to the synthetic procedure reported previously, [23][24] bis(3-amino phenyl) phenyl phosphine oxide 4 was prepared from bis(3-nitro phenyl) phen- acids 2a-f, 50 mL of acetic acid and a stirring bar were placed into a 250-mL round-bottomed flask. The mixture was stirred at room temperature overnight and refluxed for 4 hrs.…”