Synthesis of Soluble, Blue-Light-Emitting Rigid-Rod Polyamides and Polyimides Prepared from 2‘,6‘,3‘‘‘,5‘‘‘-Tetraphenyl- or Tetra(4-Biphenylyl)-4, 4‘‘‘‘-diamino-p-quinquephenyl

Abstract

2‘,6‘,3‘‘‘,5‘‘‘-Tetraphenyl- or tetra(4-biphenylyl)-4,4‘‘‘‘-diamino-p-quinquephenyls were synthesized from the corresponding pyrylium salts. Using them as starting materials, rigid-rod polyamides and polyimides containing phenyl or 4-biphenylyl side groups on the p-quinquephenyl segments of the backbone were prepared. They were characterized by inherent viscosity, elemental analysis, 1H-NMR, 13C-NMR, X-ray analysis, differential scanning calorimetry, thermomechanical analysis, thermogravimetric analysis, isothermal gravimetric analysis, and water uptake measurements. The polymers with 4-biphenylyl pendent groups showed an enhanced solubility, lower crystallinity and hydrophilicity, and higher thermal stability in comparison to the corresponding polymers with phenyl pendent groups. Polyamides displayed strong blue fluorescence in the DMF solution. The polyamide containing 4-biphenylyl pendent groups possessed a well-defined chromophore, resulting from steric interactions in the polymer chain.

Synthesis and Characterization of Novel Aromatic Polyimides from 1,4-Bis(4-aminophenyl)-2,3-diphenylnaphthalene and Aromatic Tetracarboxylic Dianhydrides

“…1 - 9 One attractive method to improve solubility is the introduction of bulky pendant phenyl group into the polyimide backbone, and a number of organic soluble polyimides having high Tgs have been successfully prepared by using aromatic diamines containing tetraphenylthiophene, 1 0 · 11 tetraphenylfuran, 12 tetraphenylpyrrole, 13 triphenylamine, 14 triphenylbenzene, 15 and tetraphenylquinquephenyl. 16 Recently, we synthesized organic soluble polyamides having high thermal stability from 1,4-bis-(4-aminophenyl)-2,3-diphenylnaphthalene and various aromatic acid dicarboxylic acid chlorides. 17 Therefore, soluble and thermally stable polyimide would be expected to be prepared from this diaminotetraphenylnaphthalene.…”

Synthesis and Characterization of Novel Aromatic Polyamides from 1,4-Bis(4-aminophenyl)-2,3-diphenylnaphthalene and Aromatic Dicarboxylic Acids

“…1 H NMR spectrum [<5 in CDC1 3 ] showed signals at 6.80--6.90 (m, 10H), 7.40 and 8.14 (ABq, 8H, 1=9Hz), 7.47 (m, 2H), and 7.52ppm (m, 2H). 13 ) of compound II and 0.3 g of 10% Pd/C in 50 ml of N,N-dimethylformamide was stirred at 70°C for 12 h under a hydrogen atmosphere. After Pd/C was removed by filtration, the solvent was evaporated under reduced pressure and the crude product was purified by distillation under reduced pressure (Glass tube oven).…”

“…1 H NMR spectrum [<5 in CDC1 3 ] showed signals at 6.57 and 6.97 (ABq, 8H, 1=8 Hz), 6.80-6.90 (m, 10H), 7.37 (m, 2H), and 7.73ppm (m, 2H). 13 Anal. Calcd for C 34 H 26 N 2 : C, 88.28%; H, 5.66%; N, 6.06%.…”

“…Several attempts have been made to improve the solubility by modifying the structure without losing their good thermal stability. Aromatic polyamides having phenyl-pendant structures such as tetraphenylthiophene, 2 -5 tetraphenylfuran, 6 tetraphenylpyrrole, 7 tetraphenylethylene, 8 triphenylamine, 9 triphenylphosphine, 10 triphenylbenzene, 11 hexaphenylbenzene, 12 and tetraphenylquinquephenyl, 13 have high thermal stability and high solubility. We conducted the synthesis of a new diamine monomer, 1 ,4-bis( 4-aminophenyl)-2,3-diphenylnaphtalene and aromatic polyamides derived from it.…”

Synthesis and Characterization of Some New Thermally Stable Crystalline Polyamides and Co-Polyamides Bearing Bipyridine Side-Chain Groups

“…Due to its importance in many areas of research, 2,2 -bipyridine has been considered in recent years [21][22][23][24][25]. Recently, a new series of polyimides and co-polyimides based on bipyridine containing diamine has been reported by our group [26].…”