Synthesis and properties of new polyamides derived from 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene and aromatic dicarboxylic acids

The diamine 1,4-bis(4-aminophenoxy)-2,5-di-tert-butylbenzene, containing symmetric, bulky di-tert-butyl substituents and a flexible ether unit, was synthesized and used to prepare a series of polyamides by the direct polycondensation with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.32–1.27 dL g⁻¹. Most of these polyamides, except II _a , II _d , and II _e , showed an amorphous nature and dissolved in polar solvents and less polar solvents. Polyamides derived from 4,4′-sulfonyldibenzoic acid, 4,4′-(hexafluoro-isopropylidene)dibenzoic acid, and 5-nitroisophthalic acid were even soluble in a common organic solvent such as THF. Most polyamide films could be obtained by casting from their N,N-dimethylacetamide (DMAc) solutions. The polyamide films had a tensile strength range of 49–78 MPa, an elongation range at break of 3–5%, and a tensile modulus range of 1.57–2.01 GPa. These polyamides had glass transition temperatures ranging between 253 and 276°C, and 10% mass loss temperatures were recorded in the range 402–466°C in nitrogen atmosphere. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1069–1074, 1998     

Synthesis and properties of aromatic polyamides derived from 1,6-bis(4-aminophenoxy)naphthalene and aromatic dicarboxylic acids

A new bis(phenoxy)naphthalene-containing diamine, 1,6-bis(4-aminophenoxy)naphthalene, was synthesized in two steps from the condensation of 1,6-dihydroxynaphthalene with p-chloronitrobenzene in the presence of potassium carbonate, giving 1,6-bis(4-nitrophenoxv)naphthalene, followed by hydrazine hydrate/Pd—C reduction. A series of polyamides were synthesized by the direct polycondensation of the diamine with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved metal salts such as CaCl₂ or LiBr using triphenyl phosphite and pyridine as condensing agents. The polymers were obtained in quantitative yield with inherent viscosities of 0.78–3.72 dL/g. Most of the polymers were soluble in aprotic solvents such as N,N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), NMP, and they could be solution-cast into transparent, flexible and tough films. The casting films had tensile strength of 102–175 MPa, elongation at break of 8–42%, and tensile modulus of 2.4–3.8 GPa. The polymers derived from rigid dicarboxylic acids such as terephthalic acid and 4,4′-biphenyldicarboxylic acid exhibited some crystalline characteristics. The glass transition temperatures of the polyamides were in the range of 238–337°C, and their 10% weight loss temperatures were above 487°C in nitrogen and above 438°C in air. © 1995 John Wiley & Sons, Inc.     

Synthesis and properties of aromatic polyamides derived from 1,2-bis(4-aminophenoxy)benzene and aromatic dicarboxylic acids

1,2-Bis(4-aminophenoxy)benzene was synthesized in two steps by the preparation of 1,2-bis(4-itrophenoxy)benzene from 1,2-dihydroxybenzene (catechol) and p-chloronitrobenzene and subsequent reduction with a 10% Pd-C catalyst and hydrazine hydrate. Aromatic polyamides with an inherent viscosity in the range of 1.08–2.00 dL/g were prepared by the direct polycondensation of this diamine with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Most of the polymers formed were soluble in aprotic solvents such as NMP and N,N-methylacetamide (DMAc), and afforded transparent, flexible, and tough films upon casting from DMAc solutions. Most of the cast films showed obvious yield points in their stress-strain curves and had tensile strength among 64–89 MPa, elongation at break among 5–23%, and initial modulus in 1.7–2.5 GPa. The glass transition temperatures (T_g) of these polymers were in the range of 207–278°C, and the 10% weight loss temperatures were recorded above 475°C in nitrogen and above 452°C in air. © 1995 John Wiley & Sons, Inc.     

Synthesis and characterization of new polyamides derived from 1,6-bis[4-(4-aminophenoxy)phenyl]diamantane

A series of new polyamides 3 were synthesized by direct polycondensation of the 1,6-bis[4-(4-aminophenoxy)phenyl]diamantane (1) with various dicarboxylic acids. The polyamides had inherent viscosities of 0.45–1.90 dL/g and number-average molecular weights (M_n) of 24,000–110,000. Dynamic mechanical analysis (DMA) reveals that polymers 3 have two relaxations on the temperature scale between −100 and 400°C. Their α relaxations occurred at high temperatures, ranging from 338 to 389°C. Moreover, these polymers remained quite stable at high temperatures and maintained good mechanical properties (G′ = ca. 10⁸ Pa) up to temperatures close to the main transition markedly exceeding 350°C. Due to the bulky diamantane elements and the flexible ether segments, the polymers 3 were amorphous and soluble in a number of organic solvents such as pyridine, N-methyl-2-pyrrolidone (NMP), and N,N-dimethylacetamide (DMAc). The polyamides 3 have tensile strengths of 56.7–90.2 MPa, elongation to breakage values of 7.5–27.7%, and initial moduli of 1.8–2.1 GPa. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2185–2192, 1998     

Synthesis and properties of aromatic polyamides derived from 1,7-bis(4-aminophenoxy)naphthalene and various aromatic dicarboxylic acids

A series of novel bis(phenoxy)naphthalene-containing polyamides having inherent viscosity up to 2.02 dL/g were synthesized by the direct polycondensation of the diamine 1,7-bis(4-aminophenoxy)naphthalene with various aromatic dicarboxylic acids in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Most of the polyamides could be readily dissolved in polar aprotic solvents such as N,N-dimethylacetamide and NMP, and could be solution-cast into transparent, flexible, and tough films. These polymers had glass transition temperatures in the range of 139–263°C, and 10% weight loss temperatures in nitrogen and air were above 499 and 484°C, respectively. © 1996 John Wiley & Sons, Inc.     

Synthesis and properties of novel aromatic polyamides derived from 1,5-bis(4-aminophenoxy)naphthalene and aromatic dicarboxylic acids

A new bis(phenoxy)naphthalene-containing diamine, 1,5-bis(4-aminophenoxy)naphthalene, was synthesized in two steps from the condensation of 1,5-dihydroxy-naphthalene with p-chloronitrobenzene in the presence of potassium carbonate, giving 1,5-bis(4-nitrophenoxy)naphthalene, followed by hydrazine hydrate/Pd? C reduction. A series of polyamides and copolyamides were synthesized by the direct polycondensation of the diamine with various aromatic dicarboxylic acids or with mixed dicarboxylic acids in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The polymers having inherent viscosity of 0.81–1.25 dL/g were obtained in quantitative yield. Most of the polymers were generally soluble in aprotic solvent such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, etc. The polymers derived from rigid dicarboxylic acids such as terephthalic acid, naphthalene dicarboxylic acid, and 4,4′-biphenyldicarboxylic acid exhibited crystalline patterns. Glass transition temperatures of polymers were in the range of 230–360°C, and 10% weight loss temperatures in nitrogen and air were above 492 and 470°C, respectively. © 1993 John Wiley & Sons, Inc.     

Synthesis and properties of aromatic polyamides derived from 2,6-bis(4-aminophenoxy)naphthalene and various aromatic dicarboxylic acids

2,6-Bis(4-aminophenoxy)naphthalene (2,6-BAPON) was synthesized in two steps from the condensation of 2,6-dihydroxynaphthalene with p-chloronitrobenzene in the presence of potassium carbonate, giving 2,6-bis(4-nitrophenoxy)naphthalene, followed by hydrazine hydrate/Pd—C reduction. A series of new polyamides were synthesized by the direct polycondensation of 2,6-BAPON with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved metal salts such as CaCl₂ or LiCl using triphenyl phosphite and pyridine as condensing agents. The polymers were obtained in quantitative yields with inherent viscosities of 0.62–2.50 dL/g. Most of the polymers were soluble in aprotic dipolar solvents such as N,N-dimethylacetamide (DMAc) and NMP, and they could be solution cast into transparent, flexible, and tough films. The casting films had yield strengths of 84–105 MPa, tensile strengths of 68–95 MPa, elongations at break of 8–36%, and tensile moduli of 1.4–2.1 GPa. The glass transition temperatures of the polyamides were in the range 155–225°C, and their 10% weight loss temperatures were above 505°C in nitrogen and above 474°C in air. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2147–2156, 1997     

Preparation and properties of aromatic polyamides and polyimides derived from 3,3-bis [4-(4-aminophenoxy) phenyl] phthalide

3,3-Bis[4-(4-aminophenoxy)phenyl]phthalide ( II ) was used as a monomer with various aromatic dicarboxylic acids and dianhydrides to synthesize polyamides and polyimides, respectively. The diamine II was derived by a nucleophilic substitution of phenolphthalein with p-chloronitrobenzene in the presence of K₂CO₃. Polyamides IV _a-g having inherent viscosities of 0.77–2.46 dL/g were prepared by the direct polycondensation of diamine II with diacids III _a-g using triphenyl phosphite and pyridine as condensing agents. The polyamides were readily soluble in a variety of solvents such as N, N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), and N-methyl-2-pyrrolidinone (NMP) and afforded transparent and flexible films from the polymer solutions. These polymers had glass transition temperatures (T_gs) in the 227–307°C range and 10% weight loss temperatures occurred up to 450°C. Polyimides VI _a-e based on diamine II and various aromatic dianhydrides V _a-e were synthesized by the two-stage procedure that included ring-opening, followed by thermal or chemical conversion to polyimides. Most of the polyimides obtained by chemical cyclodehydration procedure were found to soluble in DMF, NMP, o-chlorophenol, and m-cresol. The T_gs of these polyimides were in the 260–328°C range and showed almost no weight loss up to 500°C under air and nitrogen atmosphere. © 1994 John Wiley & Sons, Inc.     

Synthesis and characterization of polyamides and poly(amide-imide)s derived from 2,2-bis(4-aminophenoxy) benzonitrile

A series of polyamides and poly(amide-imide)s were prepared by the direct poly-condensation of 2,2-bis(4-aminophenoxy) benzonitrile [4-APBN] with aromatic dicarboxylic acids and bis(carboxyphthalimide)s in N-methyl-2-pyrrolidone [NMP] with triphenyl phosphite and pyridine as condensing agents. The synthesis of 4-APBN involves a nucleophilic displacement reaction in dipolar aprotic solvent with the alkali metal salt of p-aminophenol and an activated aromatic dichloro compound. Bis(carboxyphthalimide)s were prepared by condensation of 4,4^′-diaminodiphenylsulfone, 3,3^′-diaminodiphenylsulfone, 4,4^′-diaminodiphenylether, 4,4^′-diaminodiphenylmethane, 3,3^′-diaminobenzophenone, and trimellitic anhydride at a 1:2 molar ratio. The inherent viscosities of the resulting polymers were found to be in the range of 0.31-0.93 dl/g and glass transition temperatures between 235 and 298 °C. All polymers were soluble in aprotic polar solvents such as dimethylsulfoxide and NMP. The results of thermogravimetry revealed that all the polymers showed no significant weight loss before 400 °C. Wide-angle X-ray diffractograms revealed that all polymers were found to be amorphous except for the polyamide derived from isophthalic acid and polyamide-imides derived from diaminodiphenylether and diaminobenzophenone based bis(carboxyphthalimide)s.     

Synthesis and properties of polyimides derived from 1,4-bis(4-aminophenoxy)2,5-di-tert-butylbenzene

Novel aromatic polyimides containing symmetric, bulky di-tert-butyl substituents unit were synthesized from 1,4-bis(4-aminophenoxy)2,5-di-tert-butylbenzene (BADTB) and various aromatic tetracarboxylic dianhydrides by the conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide to give poly(amic acid)s, followed by cyclodehydration to polyimides. The diamine was prepared through the nucleophilic displacement of 2,5-di-tert-butylhydroquinone with p-chloronitrobenzene in the presence of K₂CO₃, followed by catalytic reduction. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.83–1.88 dL g⁻¹. Most of the polyimides formed transparent, flexible, and tough films. Tensile strength and elongation at break of the BADTB-based polyimide films ranged from 68–93 MPa and 7–11%, respectively. The polyimide derived from 4,4′-hexafluoro-isopropylidenebisphathalic anhydride had better solubility than the other polyimides. These polyimides had glass transition temperatures between 242–298°C and 10% mass loss temperatures were recorded in the range of 481–520°C in nitrogen. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1527–1534, 1997     

Synthesis and characterization of fluorine-containing polyamides derived from 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane by direct polycondensation

A fluorine-containing diamine, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane (BAPPH) ( II ), was synthesized in two steps on condensation of 2,2-bis(4-hydroxyphenyl)hexafluoropropane with p-chloronitrobenzene in the presence of potassium carbonate, giving 2,2-bis[4-(4-nitrophenoxy)phenyl]hexafluoropropane ( I ), followed by reduction with hydrazine monohydrate/Pd—C. Fluorine-containing polyamides and copolyamides having inherent viscosities 0.41–0.88 dL g⁻¹ were prepared by direct polycondensation of BAPPH with various aromatic diacids or with mixed diacids, by triphenyl phosphite and pyridine in N-methyl-2-pyrrolidinone (NMP). The polyamides were examined by elemental analysis, IR spectra, inherent viscosity, x-ray diffraction, solubility, DSC, and TGA. The diffractogram showed that the polyamides were crystalline except IVb , IVc , IVf , and Vc . Almost all polyamides were soluble in polar aprotic solvents. The polymers obtained from BAPPH lost no mass below 350°C, with 10% loss of mass being recorded above 467°C in nitrogen. These aromatic polyamides had glass transition temperatures in the 221–253°C range. © 1996 John Wiley & Sons, Inc.     

Polyimides derived from 1,2-bis(4-aminophenoxy)propane

The diamine 1,2-bis(4-aminophenoxy)propane, containing the flexible 1,4-dioxa-2-methylbutyl-ene unit, was synthesized. Polyimidization was carried out with 5,5′-[2,2,2-trifluoro-(trifluoromethyl)ethylidine]bis-1,3-isobenzofurandione in m-cresol employing toluene as azeotroping agent to yield a polyimide that was soluble in a variety of solvents and had an inherent viscosity of 0.84 dL/g in N,N-dimethylformamide. Poly(amic acid) formation with pyromellitic dianhydride, 4,4′-carbonyldiphthalic anhydride, and 5,5′-[ethanediylbis(oxy)]-bis-1,3-isobenzofurandione was carried out in N,N-dimethylformamide with imidization completed by heating at 160°C for 24 h under vacuum. All of the polyimides exhibited a 5% weight loss in air and in helium by 420°C.     

Synthesis and properties of polyimides derived from 1,6-bis(4-aminophenoxy)naphthalene and aromatic tetracarboxylic dianhydrides

1,6-Bis(4-aminophenoxy)naphthalene ( I ) was used as a monomer with various aromatic tetracarboxylic dianhydrides to synthesize polyimides via a conventional two-stage procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide (DMAc) to give poly(amic acid)s, followed by thermal cyclodehydration to polyimides. The diamine ( I ) was prepared through the nucleophilic displacement of 1,6-dihydroxynaphthal-ene with p-chloronitrobenzene in the presence of K₂CO₃, followed by catalytic reduction. Depending on the dianhydrides used, the poly(amic acid)s obtained had inherent viscosities of 0.73–2.31 dL/g. All the poly(amic acid)s could be solution cast and thermally converted into transparent, flexible, and tough polyimide films. The polyimide films had a tensile modulus range of 1.53–1.84 GPa, a tensile strength range of 95–126 MPa, and an elongation range at break of 9–16%. The polyimide derived from 4,4′-sulfonyldiphthalic anhydride (SDPA) had a better solubility than the other polyimides. These polyimides had glass transition temperatures between 248–286°C (DSC). Thermogravimetric analyses established that these polymers were fairly stable up to 500°C, and the 10% weight loss temperatures were recorded in the range of 549–595°C in nitrogen and 539–590°C in air atmosphere. © 1995 John Wiley & Sons, Inc.     

Synthesis and properties of polyimides derived from 1,7-bis(4-aminophenoxy)naphthalene and aromatic tetracarboxylic dianhydrides

The novel diamine, 1,7-bis(4-aminophenoxy)naphthalene (1,7-BAPON), was synthesized and used to prepared polyimides. 1,7-BAPON was synthesized through the nucleophilic displacement of 1,7-dihydroxynaphthalene with p-fluoronitrobenzene in the presence of K₂CO₃ followed by catalytic-reduction. Polyimides were prepared from 1,7-BAPON and various aromatic tetracarboxylic dianhydrides by the usual two-step procedure that included ring-opening polyaddition to give poly(amic acid)s, followed by cyclodehydration to polyimides. The poly(amic acid)s had inherent viscosities of 0.74-2.48 dL/g. Most of the polyimides formed tough, creasible films. These polyimides had glass transition temperatures between 247–278°C and their 10% weight loss temperatures were recorded in the range of 515–575°C in nitrogen atmosphere. © 1995 John Wiley & Sons, Inc.     

Synthesis and characterization of soluble polyamides based on 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane and 2,2-bis[4-(4-aminophenoxy)phenyl]propane and diacid chlorides

Aromatic soluble polyamides and copolyamides having hexafluoroisopropylidene and isopropylidene moieties in the molecular structure of polymer chain were prepared by reacting the aromatic diacid chlorides and fluorine or nonfluorine containing aromatic diamines using low-temperature polycondensation process. Polymers were produced with high yield and moderate to high inherent viscosity. All polyimides and copolyamides showed thermal stability above 440°C and glass transition temperature above 200°C. Some of the polyamides were cast into transparent bulk films which were further characterized by mechanical, x-ray, and water absorption analysis. Fluoro polyamides showed superior structural properties as compared to nonfluoro polyamides. © 1996 John Wiley & Sons, Inc.     

Synthesis and properties of new polyimides derived from 1,5-bis(4-aminophenoxy)naphthalene and aromatic tetracarboxylic dianhydrides

Novel aromatic polyimides containing bis(phenoxy)naphthalene units were synthesized from 1,5-bis(4-aminophenoxy)naphthalene (APN) and various aromatic tetracarboxylic dianhydrides by the usual two-step procedure that included ring-opening polyaddition in a polar solvent such as N,N-dimethylacetamide (DMAc) to give poly(amic acid)s, followed by cyclodehydration to polyimides. The poly(amic acid)s had inherent viscosities between 0.72 and 1.94 dL/g, depending on the tetracarboxylic dianhydrides used. Excepting the polyimide IVb obtained from 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA), all other polyimides formed brown, flexible, and tough films by casting from the poly(amic acid) solutions. The polyimide synthesized from BPDA was characterized as semicrystalline, whereas the other polyimides showed amorphous patterns as shown by the x-ray diffraction studies. Tensile strength, initial moduli, and elongation at break of the APN-based polyimide films ranged from 105–135 MPa, 1.92–2.50 GPa, and 6–7%, respectively. These polyimides had glass transition temperatures between 228 and 317°C. Thermal analyses indicated that these polymers were fairly stable, and the 10% weight loss temperatures by TGA were recorded in the range of 543–574°C in nitrogen and 540–566°C in air atmosphere, respectively. © 1993 John Wiley & Sons, Inc.     

IR spectroscopy and single crystal X-ray diffraction study of 1,2-bis(2-aminophenoxy)-ethane, 1,5-bis(2-aminophenoxy)-3-oxapentane,and 1,8-bis(2-aminophenoxy)-3,6-dioxaoctane

Vibrational spectra of 1,2-bis(2-aminophenoxy)-ethane, 1,5-bis(2-aminophenoxy)-3-oxapentane, and 1,8-bis(2-aminophenoxy)-3,6-dioxaoctane–podands, different in the length of oxyethylene fragments, are measured and their single crystal X-ray diffraction analysis is performed. It is demonstrated that the strength of intermolecular hydrogen bonds (IMHB) with the participation of NH groups increases with the elongation of the oxyethylene spacer. According to the XRD data for 1,2-bis(2-aminophenoxy)-ethane, the weakest hydrogen bonds are characteristic. From the IR spectra, important intermolecular hydrogen bonds are typical of 1,8-bis(2-aminophenoxy)-3,6-dioxaoctane having the longest oxyethylene fragment.     

Synthesis and characterization of new soluble polyamides derived from 2,6-bis(4-aminophenyl)-3,5-dimethyltetrahydro-4H-pyran-4-one

A new oxypyrone diamine, 2,6-bis(4-aminophenyl)-3,5-dimethyltetrahydro-4H-pyran-4-one (DAPP), was prepared from 4-nitrobenzaldehyde and 3-oxa-n-pentane in a two-step reaction with a high yield and a high purity. Aromatic polyamides were obtained from this novel condensation monomer and several diacid chlorides through the conventional low-temperature solution method in N,N-dimethylacetamide. Polycondensation results were consistent with a high reactivity for DAPP because high yields and high molecular weight polyamides were obtained with inherent viscosities up to 1.8 dL/g. The reactivity of DAPP was also estimated with theoretical calculations from computer programs for molecular simulation, with orbital and charge factors considered. The polymers showed improved solubility in organic solvents, relative to conventional wholly aromatic polyamides, and high glass-transition temperatures (from differential scanning calorimetry) over 270 °C. However, the thermal resistance, as estimated by thermogravimetric analysis, was lower than that of conventional aromatic polyamides; nevertheless, decomposition temperatures well beyond 300 °C were observed in nitrogen and air. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1825–1832, 2001     

Synthesis and characterization of novel polyimides derived from 4-phenyl-2, 6-bis [3-(4-aminophenoxy)-phenyl]-pyridine diamine and aromatic dianhydrides

A new kind of pyridine-containing aromatic diamine monomer, 4-phenyl-2, 6-bis [3-(4-aminophenoxy)phenyl]-pyridine(m-PAPP),was synthesized by a modified Chichibabin reaction of benzaldehyde and a substituted acetophenone, 3-(4-nitrophenoxy)-acetophenone(m-NPAP), and a reduction of the resulting dinitro compound 4-phenyl-2, 6-bis[3-(4-nitrophenoxy)phenyl]-pyridine (m-PNPP) with Pd/C and hydrazine monohydrate, successively. A series of novel aromatic polyimides were prepared from the diamine with various aromatic dianhydrides via a conventional two-step thermal or chemical imidization method. The inherent viscosities of the resulting poly (amic acid) precursors were 1.37-1.56 dL/g, and these polymers could be cast and thermally converted into transparent, flexible, and tough polyimide films. The polyimides displayed higher solubility in polar solvents such as NMP, DMSO and m-cresol. The glass transition temperatures of these polymers were recorded at 180-264 °C. All of these novel polyimides held 10% weight loss at the temperature above 430 °C and left more than 50% residue even at 800 °C in air, as well as have outstanding mechanical properties with the tensile strengths of 91.6-114.1 MPa and elongations at breakage of 10.1-15.7%. Wide-angle X-ray diffraction measurements revealed that these polyimides were predominantly amorphous.     

Syntheses and properties of aromatic polyamides and polyimides derived from 9,9-bis[4-(p-aminophenoxy)phenyl]fluorene

9,9-Bis[4-(p-aminophenoxy)phenyl]fluorene ( II ) was used as a monomer with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to synthesize polyamides and polyimides, respectively. The diamine II was derived by a nucleophilic substitution of 9,9-bis(4-hydroxyphenyl)fluorene with p-chloronitrobenzene in the presence of K₂CO₃ and then hydro-reduced. Polyamides IV _a-g having inherent viscosities of 0.73–1.39 dL/g were prepared by the direct polycondensation of the diamine II with various aromatic diacids using triphenyl phosphite and pyridine as condensing agents. All the aromatic polyamides were amorphous and readily soluble in various polar solvents such as N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, and N-methyl-2-pyrrolidone. Transparent and flexible films of these polymers could be cast from the DMAc solutions. These aromatic polyamides had glass transition temperatures in the range of 283–309°C and 10% weight loss occurred up to 460°C. The polyimides were synthesized from diamine II and various aromatic dianhydrides via the two-stage procedure that included ring-opening poly-addition in DMAc to give poly(amic acid)s, followed by thermal or chemical conversion to polyimides. The poly(amic acid)s had inherent viscosities of 0.62–1.78 dL/g, depending on the dianhydrides. Most of the aromatic polyimides obtained by chemical cyclization were found to be soluble in NMP. These polyimides showed almost no weight loss up to 500°C in air or nitrogen atmosphere. © 1993 John Wiley & Sons, Inc.