New organosoluble and thermally stable poly(urea‐imide)s prepared from one‐pot polyaddition reactions

Abstract

A new class of aromatic poly(urea-imide)s having biphenylene pendant group was prepared by the diphenyl azidophosphate (DPAP) activated one-pot polyaddition reaction of a preformed imide ring-containing dicarboxylic acid, 4-p-biphenyl-2,6-bis(4-trimellitimidophenyl)pyridine (1) with various aromatic diamines. A model compound was also synthesized by the reaction of diimide-dicarboxylic acid 1 with two mole equivalents of aniline. In this direct method the polymers were prepared by polyaddition reactions of the in situ-formed diisocyanate with the aromatic diamines. The inherent viscosities of the polymers were measured in the range of 0.11-0.15 dL g 21. The ultraviolet k max values of the poly(urea-imide)s were also determined.Furthermore, crystallinity of the resultant polymers was evaluated by wide-angle X-ray diffraction method, and they exhibited nearly a noncrystalline nature. All of the resulting polymers exhibited excellent solubility in common polar solvents. The glass transition temperatures of the polymers determined by DSC thermograms were in the range 241-2728C. The temperatures at 10% weight loss from their TGA curves were found to be in the range 406-4378C in nitrogen.

Flip‐Flop einer Wasserstoffbrücke durch einen Bjerrum’schen Defekt

“…In our previous studies we successfully prepared a series of wholly aromatic polymers from a number of structurally modified monomers 31–39. As a continuation, in the present study, we report the synthesis and characterization of novel wholly aromatic polyamides derived from PPAPE and two simple aromatic comonomers.…”

Synthesis and characterization of new soluble and thermally stable poly(amide‐imide)s containing pendent benzimidazole moieties

“…Behniafar reported that the ultraviolet maximum wavelengths (λ max 's) of the polymers depending upon π to π* allowed transitions were also determined and ranged between 292 and 319 nm. Generally, the highly conjugated aromatic structures of the obtained polymers lead to various absorption bands in their UV‐Vis spectra, as a number of broad and sharp peak, which could be attributed to the various of allowed and forbidden electron transitions 24…”

Preparation and properties of flame retardant poly(urethane‐imide)s containing phosphine oxide moiety

“…29,36,37 Moreover, the use of an isocyanate monomer prepared in situ by the Curtius rearrangement in performing a polymerization reaction results in commonly the low yield and lower molecular weight products. 47,48 …”