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Chin-ping Yang - One of the best experts on this subject based on the ideXlab platform.

  • Fluorinated Aromatic Polyamides and Poly(amide‐imide)s: Synthesis and Properties
    Macromolecular Chemistry and Physics, 2005
    Co-Authors: Chin-ping Yang
    Abstract:

    A CF 3 -containing diamine, 4,4'-bis(4-amino-2-trifluoromethylphenoxy)biphenyl (I), was synthesized from 4,4'-biphenol and 2-chloro-5-nitrobenzotrifluoride. The imide-containing diacids (V a-b and VI a-1 ) were prepared by condensation reaction of amino acids, aromatic diamines and trimellitic anhydride. Then, a series of soluble aromatic polyamides (VII a-f ) and poly(amide-imide)s (VIII a-b and IX a-1 ) were synthesized from diamine I with various aromatic diacids (II a-f ) and the imide-containing diacids (V a-b and VI a-1 ) via direct polycondensation with triphenyl phosphate and pyridine. Aromatic polyamides and poly(amide-imide)s had inherent viscosities of 0.60-0.85 dL/g and 0.52-1.44 dL/g, respectively. All synthesized polymers showed excellent solubility in amide-type solvents such as N-methyl-2-pyrrolidinone, N,N-dimethylacetamide (DMAc) and N-dimethylforamide and afford transparent and tough films by DMAc solvent casting. These polymer films had tensile strengths of 87-135 MPa, elongations to break of 8-22%, and initial moduli of 2.0-3.0 GPa. Glass transition temperature of these polymers were in the range of 259-317 °C, and the poly(amide-imide)s had better thermal stability than aromatic polyamides. In comparison with the isomeric X series, the IX series exhibited less coloring and showed a lower b* (yellowness index) values than the corresponding IX series.

  • Synthesis and properties of organosoluble poly(amide‐imide)s with propeller‐shaped 1,1,1‐triphenylethane units in the main chain
    Journal of Polymer Science Part A: Polymer Chemistry, 2001
    Co-Authors: Chin-ping Yang, Ruei-shin Chen, Ching-der Chen
    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 properties of poly(amide–imide)s containing a N-methylcarbazole group
    Colloid & Polymer Science, 2000
    Co-Authors: Chin-ping Yang, Ruei-shin Chen, C.-c. Chang
    Abstract:

    A new dicarboxylic acid monomer containing the N-methylcarbazole and imide structures, 3,6-bis(trimellitimido)-N-methylcarbazole (I), was prepared from the condensation of 3,6-diamino-N-methylcarbazole (c) and trimellitic anhydride. The diamine c was synthesized in three steps starting from the methylation of carbazole, followed by nitration and catalytic hydrazine reduction. A series of N-methylcarbazole-containing poly(amide–imide)s were synthesized by direct polycondensation from the diimide–diacid I with various aromatic diamines. These poly(amide–imide)s had inherent viscosities of 0.66–1.47 dl/g and were readily soluble in a variety of organic solvents, including N-methyl-2-pyrrolidone and N,N-dimethylacetamide (DMAc). Transparent, flexible, and tough films of these polymers could be cast from DMAc solutions, and these films exhibited excellent mechanical strength. The glass-transition temperatures of these poly(amide–imide)s were in the range 317–362 °C. All the poly (amide–imide) did not degrade noticeably below 480 °C in nitrogen, and the 10% weight loss temperatures and char yields at 800 °C were above 520 °C and 60% in nitrogen, respectively, indicating high thermal stability.

  • synthesis and characterization of new aromatic poly amide imide s derived from 1 4 bis 4 aminophenoxy 2 t butylbenzene and various bis trimellitimide s
    Materials Chemistry and Physics, 2000
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hueiwen Yang
    Abstract:

    Abstract A series of novel t-butyl group-containing poly(amide–imide)s III a – m were synthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s II a – m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide–imide)s III having inherent viscosities between 0.67 and 1.77 dl g−1 were obtained in quantitative yields. Most of the resulting polymers were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 243–300°C, and the 10% weight loss temperatures were above 490°C in nitrogen. The properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s III′ prepared from the bis(trimellitimide) of BAP-tBB and various aromatic diamines.

  • Preparation and properties of new poly(amide-imide)s based on 1,4-bis(4-trimellitimidophenoxy)naphthalene and aromatic diamines
    Journal of Polymer Science Part A: Polymer Chemistry, 2000
    Co-Authors: Chin-ping Yang, Ruei-shin Chen, Jhy-an Chen
    Abstract:

    A diimide dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)naphthalene (1,4-BTMPN), was prepared by condensation of 1,4-bis(4-aminophenoxy)naphthalene and trimellitic anhydride at a 1 : 2 molar ratio. A series of novel poly(amide-imide)s (IIa–k) with inherent viscosities of 0.72 to 1.59 dL/g were prepared by triphenyl phosphite-activated polycondensation from the diimide-diacid 1,4-BTMPN with various aromatic diamines (Ia–k) in a medium consisting of N-methyl-2-pyrrolidinone (NMP), pyridine, and calcium chloride. The poly(amide-imide)s showed good solubility in NMP, N,N-dimethylacetamide, and N,N-dimethylformamide. The thermal properties of the obtained poly(amide-imide)s were examined with differential scanning calorimetry and thermogravimetry analysis. The synthesized poly(amide-imide)s possessed glass-transition temperatures in the range of 215 to 263°C. The poly(amide-imide)s exhibited excellent thermal stabilities and had 10% weight losses at temperatures in the range of 538 to 569°C under a nitrogen atmosphere. A comparative study of some corresponding poly(amide-imide)s also is presented. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1–8, 2000

Sheng-huei Hsiao - One of the best experts on this subject based on the ideXlab platform.

  • Synthesis and properties of novel organosoluble and light-colored poly(ester-amide)s and poly(ester-imide)s with triptycene moiety
    Journal of Polymer Research, 2018
    Co-Authors: Sheng-huei Hsiao, Yu-chuan Liao
    Abstract:

    Two series of new triptycene-containing poly(ester-amide)s and poly(ester-imide)s were prepared from 1,4-bis(3-aminobenzoyloxy)triptycene with various aromatic dicarboxylic acids and dianhydrides, respectively. The synthesis of the poly(ester-amide)s was achieved by the phosphorylation polyamidation reaction by means of triphenyl phosphite and pyridine, and the synthesis of the poly(ester-imide)s included ring-opening polyaddition to give poly(amic acid)s followed by thermal imidization and chemical imidization to polyimides. All the poly(ester-amide)s and most of the poly(ester-imide)s presented good solubility in many organic solvents and could be solution-cast into transparent and flexible films. These poly(ester-amide)s and poly(ester-imide)s displayed discernible glass-transition temperatures (Tgs) between 242 and 298 °C in the DSC traces and showed moderate thermal stability with 10 wt% loss temperatures above 464 °C in nitrogen or air. These highly optically transparent polymer films possess an ultraviolet-visible absorption cut-off wavelength (λ0) down to 344 nm. 1,4-Bis(4-aminobenzoyloxy)triptycene was also synthesized and used for polymer synthesis; however, less favorable results were obtained.

  • synthesis and characterization of new aromatic poly amide imide s derived from 1 4 bis 4 aminophenoxy 2 t butylbenzene and various bis trimellitimide s
    Materials Chemistry and Physics, 2000
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hueiwen Yang
    Abstract:

    Abstract A series of novel t-butyl group-containing poly(amide–imide)s III a – m were synthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s II a – m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide–imide)s III having inherent viscosities between 0.67 and 1.77 dl g−1 were obtained in quantitative yields. Most of the resulting polymers were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 243–300°C, and the 10% weight loss temperatures were above 490°C in nitrogen. The properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s III′ prepared from the bis(trimellitimide) of BAP-tBB and various aromatic diamines.

  • Synthesis and Properties of Poly(Amide-Imide-Hydrazide)s and Poly(Amide-Imide-1,3,4-Oxadiazole)s
    High Performance Polymers, 2000
    Co-Authors: Sheng-huei Hsiao, Li-min Chang
    Abstract:

    A series of new wholly aromatic and aromatic-aliphatic poly(amide-imide-hydrazide)s were prepared by the direct polycondensation from p-aminobenzhydrazide with various imide ring-containing dicarboxylic acids by means of diphenyl phosphite and pyridine. These polymers had inherent viscosities between 0.60 and 1.17 dl g−1. Most of the poly(amide-imide-hydrazide)s were readily soluble in polar aprotic solvents such as N-methyl-2-pyrrolidone (NMP) and dimethyl sulfoxide (DMSO) and could be solution cast into light yellow, transparent, flexible, and tough films. These poly(amide-imide-hydrazide)s had Tg in the range 122–211 °C and could be thermally cyclodehydrated in the solid state to the corresponding poly(amide-imide-1,3,4-oxadiazole)s approximately in the range 250–400 °C, as evidenced by the differential scanning calorimetry thermograms. The thermally converted oxadiazole copolymers exhibited Tg in the range 120–271 °C and did not show significant weight loss before 380 °C in air or nitrogen. Effects of...

  • Synthesis and characterization of new aromatic poly(amide–imide)s derived from 1,4-bis(4-aminophenoxy)-2-t-butylbenzene and various bis(trimellitimide)s
    Materials Chemistry and Physics, 2000
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hueiwen Yang
    Abstract:

    Abstract A series of novel t-butyl group-containing poly(amide–imide)s III a – m were synthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s II a – m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide–imide)s III having inherent viscosities between 0.67 and 1.77 dl g−1 were obtained in quantitative yields. Most of the resulting polymers were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 243–300°C, and the 10% weight loss temperatures were above 490°C in nitrogen. The properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s III′ prepared from the bis(trimellitimide) of BAP-tBB and various aromatic diamines.

  • New poly(amide–imide)s syntheses. XXIII. Synthesis and properties of poly(amide–imide)s derived from 4,4′-[1,4-phenylenebis(isopropylidene-1,4-phenyleneoxy)]dianiline and various bis(trimellitimide)s
    Journal of Polymer Science Part A: Polymer Chemistry, 1999
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hsiu-chun Hsiao
    Abstract:

    A series of poly(amide–imide)s IIIa–m containing flexible isopropylidene and ether groups in the backbone were synthesized by the direct polycondensation of 4,4′-[1,4-phenylenebis(isopropylidene-1,4-phenyleneoxy)]dianiline (PIDA) with various bis(trimellitimide)s IIa–m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The resulting poly(amide–imide)s had inherent viscosities in the range of 0.80–1.36 dL/g. Except for those from the bis(trimellitimide)s of p-phenylenediamine and benzidine, all the polymers could be cast from DMAc into transparent and tough films. They exhibited excellent solubility in polar solvents. The 10% weight loss temperatures of the polymers in air and in nitrogen were all above 495°C, and their Tg values were in the range of 201–252°C. Some properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s V prepared from the bis(trimellitimide) of diamine PIDA and various aromatic diamines. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 69–76, 1999

Jiun-hung Lin - One of the best experts on this subject based on the ideXlab platform.

  • New poly(amide‐imide)s syntheses. XVII. Preparation and properties of poly(amide‐imide)s derived from 3,3‐Bis[4‐(4‐aminophenoxy)phenyl]phthalimidine and various bis(trimellitimide)s
    Journal of Polymer Science Part A, 1996
    Co-Authors: Chin-ping Yang, Jiun-hung Lin
    Abstract:

    Fifteen bis(phenoxy) fluorene-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 9,9-bis[4-(4-aminophenoxy)phenyl]fluorene (BAPPF) with var-ious aromatic bis(trimellitimide)s II in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III having inherent vis-cosities up to 1.45 dL/g were obtained in quantitative yields. 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 transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 263–315°C and the 10% weight loss temperatures were above 510°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III′ prepared from 9,9-[4-(4-trimellitimidophenoxy)phenyl]fluorene and various aromatic diamines. © 1995 John Wiley & Sons, Inc.

  • New poly(amide‐imide) syntheses, 19. Preparation and properties of poly(amide‐imide)s derived from N‐phenyl‐3,3‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐oxoisoindoline and various bis(trimellitimide)s
    Macromolecular Chemistry and Physics, 1996
    Co-Authors: Jiun-hung Lin, Chin-ping Yang
    Abstract:

    A series of novel bis(phenoxy)-1-oxoisoindoline-containing poly(amide-imide)s 3 were synthesized by the direct polycondensations of N-phenyl-3,3-bis[4-(4-aminophenoxy)-phenyl]-1-oxoisoindoline (1m, NPBA) with various aromatic bis(trimellitimide)s 2 in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s 3 having inherent viscosities up to 1,06 dL/g were obtained in quantitative yields. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide-imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 277-327 °C, and the 10% weight loss temperatures were above 500°C in nitrogen. The properties of poly(amideimide)s 3 were compared with those of the corresponding isomeric poly(amide-imide)s 3' prepared from NPBA and various aromatic diamines.

  • New poly(amide‐imide)s synthesis, 16. Preparation and properties of poly(amide‐imide)s derived from 3,3‐bis[4‐(4‐aminophenoxy) phenyl]phthalide and various bis(trimellitimide)s
    Macromolecular Chemistry and Physics, 1995
    Co-Authors: Cnin-ping Yang, Jiun-hung Lin
    Abstract:

    A series of novel bis(phenoxy)phthalide-containing poly(amide-imide)s 3 were synthesized via direct polycondensation of 3,3-bis[4-(4-aminophenoxy)phenyl]phthalide (BAPP) with various aromatic bis(trimellitimide)s 2 in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s 3 having inherent viscosities up to 1,68 dL/g were obtained in quantitative yields. 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 transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 237–292°C and the 10% weight loss temperatures were above 500°C in nitrogen. The properties of poly(amide-imide)s 3 were compared with those of the corresponding isomeric poly(amide-imide)s 3′ prepared from 3,3-[4-(4-trimellitimido-phenoxy)phenyl]-phthalide and various aromatic diamines.

  • New poly(amide‐imide)s syntheses, 14. Preparation and properties of poly(amide‐imide)s based on 3, 3‐bis[4‐(4‐trimellitimidophenoxy)phenyl]‐1‐oxoisoindoline
    Macromolecular Chemistry and Physics, 1995
    Co-Authors: Chin-ping Yang, Jiun-hung Lin
    Abstract:

    An imide ring-containing dicarboxylic acid, 3,3-bis[4-(4-trimellitimidophenoxy)phenyl]-1-oxoisoindoline, was prepared via condensation of 3,3-bis[4-(4-aminophenoxy)phenyl]-1-oxoisoindoline and trimellitic anhydride. A series of new aromatic bis(phenoxy)-1-oxoisoindoline-containing poly(amide-imide)s were prepared via direct polycondensation of this diimide-diacid with various aromatic diamines using triphenyl phosphite and pyridine as condensing agents in N-methyl-2-pyrrolidone (NMP) in the presence of calcium chloride. Most of the resulting polymers are of amorphous nature and readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All soluble poly(amide-imide)s afford transparent, flexible, and tough films. The glass transition temperatures of the polymers are in the range of 267 - 305 °C and show almost no weight loss up to 450 °C in nitrogen atmosphere. The properties of 1-oxoisoindoline containing poly(amide-imide)s are compared with those of the corresponding analogous poly(amide-imide)s derived from 3,3-bis[4-(4-trimellitimidophenoxy)phenyl]phthalide.

  • New poly(amide-imide) syntheses, 4 Poly(amide-imide)s derived from 2,5-bis(4-aminophenyl)-3,4-diphenylthiophene and various bis(trimellitimide)s†
    Die Makromolekulare Chemie, 1992
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Jiun-hung Lin
    Abstract:

    Fifteen bis(trimellitimide)s 2a–o were prepared by condensation of the corresponding aliphatic or aromatic diamines with trimellitic anhydride. A series of structurally new poly(amideimide)s were synthesized by the direct polycondensation of these bis(strimellitimide)s with 2,5-bis(4-aminophenyl)-3,4-diphenylthiophene using triphenyl phosphite and pyridine as condensing agents in N-methyl-2-pyrrolidone (NMP). The resultant poly(amide-imide)s have inherent viscosities in the range between 0,72 and 2,73 dL/g at 30°C in N,N-dimethylacetamide (cf. Tab. 2). The polymers are amorphous and readily soluble in polar aprotic solvents such as N,N-dimethylacetamide (DMAc) and NMP. Transparent and tough films can be cast from their solutions. Most aliphatic-aromatic poly(amide-imide)s show a glass transition in the range between 203 and 242°C in their differential scanning calorimetry (DSC) traces, whereas the wholly aromatic poly(amide-imide)s show no discernible transition before decomposition. The thermal stability of the polymers was evaluated by thermogravimetry which showed the 10% weight-loss temperatures in the range between 414 and 459°C in air and between 451 and 578°C in a nitrogen atmosphere for the aliphatic-aromatic poly(amide-imide)s and above 500°C in both air and nitrogen atmosphere for the wholly aromatic poly(amide-imide)s.

Khalil Faghihi - One of the best experts on this subject based on the ideXlab platform.

Hueiwen Yang - One of the best experts on this subject based on the ideXlab platform.

  • synthesis and characterization of new aromatic poly amide imide s derived from 1 4 bis 4 aminophenoxy 2 t butylbenzene and various bis trimellitimide s
    Materials Chemistry and Physics, 2000
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hueiwen Yang
    Abstract:

    Abstract A series of novel t-butyl group-containing poly(amide–imide)s III a – m were synthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s II a – m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide–imide)s III having inherent viscosities between 0.67 and 1.77 dl g−1 were obtained in quantitative yields. Most of the resulting polymers were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 243–300°C, and the 10% weight loss temperatures were above 490°C in nitrogen. The properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s III′ prepared from the bis(trimellitimide) of BAP-tBB and various aromatic diamines.

  • Synthesis and characterization of new aromatic poly(amide–imide)s derived from 1,4-bis(4-aminophenoxy)-2-t-butylbenzene and various bis(trimellitimide)s
    Materials Chemistry and Physics, 2000
    Co-Authors: Chin-ping Yang, Sheng-huei Hsiao, Hueiwen Yang
    Abstract:

    Abstract A series of novel t-butyl group-containing poly(amide–imide)s III a – m were synthesized by the direct polycondensations of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) with various aromatic bis(trimellitimide)s II a – m in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide–imide)s III having inherent viscosities between 0.67 and 1.77 dl g−1 were obtained in quantitative yields. Most of the resulting polymers were readily soluble in polar solvents such as NMP and N,N-dimethylacetamide. All of the soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 243–300°C, and the 10% weight loss temperatures were above 490°C in nitrogen. The properties of poly(amide–imide)s III were compared with those of the corresponding poly(amide–imide)s III′ prepared from the bis(trimellitimide) of BAP-tBB and various aromatic diamines.