Synthesis and properties of organosoluble poly(amide-imide)s with propeller-shaped 1,1,1-triphenylethane units in the main chain

Abstract

A dicarboxylic acid {1,1‐bis[4‐(4‐trimellitimidophenoxy)phenyl]‐1‐phenylethane (II)} bearing two performed imide rings was prepared from the condensation of 1,1‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐phenylethane and trimellitic anhydride in a 1/2 molar ratio. A novel family of poly(amide‐imide)s with inherent viscosities of 0.83–1.51 dL/g was prepared by triphenyl phosphite‐activated polycondensation from the diimide‐diacid II with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidinone (NMP), pyridine, and calcium chloride. Because the 1,1,1‐triphenylethane group of II was unsymmetrical, most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded tough, transparent, and flexible films, which had tensile strengths ranging from 88 to 102 MPa, elongations at break from 6 to 11%, and initial moduli from 2.23 to 2.71 GPa. The synthesized poly(amide‐imide)s possessed glass‐transition temperatures from 250 to 287 °C. The poly(amide‐imide)s exhibited excellent thermal stabilities and had 10% weight losses from 501 to 534 °C under a nitrogen atmosphere. A comparative study of some corresponding poly(amide‐imide)s is also presented. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 775–787, 2001

Synthesis and characterization of new aromatic poly(amide-imide)s derived from bis(3-trimellitimidophenyl) phenyl phosphine oxide and various aromatic diamines

“…The 13 C NMR spectrum of diimide-diacid (I) shows 17 signals, including 3 signals of carbon atoms associated with carboxylic acid and imide (C 1,8,9 ) and 14 signals of carbon atoms present in the aromatic rings (C 2-7 , C [10][11][12][13][14][15][16][17][18][19] ). The expected signals for aromatic carbons are 15, while the actual NMR measurement showed 14 signals, which is due to overlap of two carbons bands (Fig.…”

New optically active poly(amide-imide)s based on N,N′-(pyromellitoyl)-bis-L-amino acid and methylene diphenyl-4,4′-diisocyanate: synthesis and characterization

“…[19,20] Therefore, modifications of PI's chemical structure are of great importance so as to overcome the above-mentioned shortcomings. One common approach is to introduce asymmetric units or bulky substituents into the polymer backbones [19,21,22] that possess various copolyimides such as poly(amide-imide)s (PAIs). [16,17,20,23] There is a growing interest in optically active poly(amide-imide)s (OAPAIs) in enantiomeric molecular recognition in chromatography, [24,25] ferroelectrics and nonlinear optical devices, [26] and separation membranes.…”

Synthesis and Investigation of Transition Metal Removing of Novel Thermally Stable Polyamides bearing Calix[4]arene in their Backbones

“…These properties make them generally intractable or difficult to process, thus restricting their utilizations. Many studies (3)(4)(5) have been applied to enhance their processability and solubility while minimizing the deterioration of their physical properties (6,7), by introducing pendent groups (8,9) or molecular asymmetry (breaking its symmetry) (10,11) or flexible linkages (12,13) into the polyamide backbone to destroy highly directional hydrogen bonds and donor/acceptor interaction of the amide functions that causes chain stiffness. In the last decade, huge efforts have been performed to incorporate new functionalities in the polyamide backbone to combine their intrinsic thermal/mechanical properties with a desired capability to approach novel industrial application of these materials.…”