Synthesis and characterization of photoelectronic polymers containing triphenylamine moiety

Several polymers containing triphenylene moieties in main chain were synthesized by Knovenagel or Wittig condensations. The polymers were characterized by ¹H NMR, IR, GPC, TG, UV–vis, FL and CV. Results indicated that PNB, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with 1,4-bis(triphenylphosphonionmethyl)benzene dibromide, is the most thermally stable one and that PNP, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with p-phenylene diacetonitrile, is the most thermally instable one. The fluorescence quantum efficiency of PNB is 94.3%, which is a high value for optoelectronic polymer materials. All the polymers have a similar CV curve with a reversible oxidation peak and two reduction peaks except that PNB has a single reduction peak.     

BTDA型聚酰胺酸和聚酰亚胺的微波辐射合成

在微波辐射条件下,将3,3′,4,4′-二苯酮四羧酸二酐(BTDA)、4,4′-二氨基二苯醚(ODA)和3,5-二氨苯甲酸(DABA)在少量非极性溶剂N,N′-二甲基甲酰胺(DMF)的存在下进行共缩聚反应,快速而高效地合成了聚酰胺酸(PAA)和聚酰亚胺(PI)。采用特性粘数、红外光谱(FT-IR)和核磁共振(1HNMR)对聚合物的结构进行了表征,利用热失重分析(TGA)对其热性能进行了测试,并测定了聚合物在多种溶剂中的溶解性。实验结果表明,微波辐射溶液聚合能够提高PAA的特性粘数及产率,微波的引入大大缩短了反应时间;FT-IR表明,在1779cm-1、1723cm-1、1239cm-1和1378cm-1处观察到聚酰亚胺特征峰;TG表明,PI在氮气中10%热失重温度(Td10%)为576℃。     

Changes of fluorescence color in novel poly(azomethine) by the acidity variation

A novel polymer, poly(4,4′‐oxydiphenylenemethylidynenitrilo‐2,5‐dihexyloxy‐1,4‐phenylenenitrilomethyli‐ dyne) (POPNM), with a azomethine structure, containing long alkoxy side chains, was synthesized by the polycondensation of 2,5‐bis(hexyloxy)terephthalaldehyde with 4,4′‐oxydianiline. It displayed acid‐sensory properties as colorimetric and fluorescent transducers to the strong acid analytes because of the protonation of an imine group in the compound. To examine the sensitivity to the acid, the effect of absorption and fluorescence of the polymer was investigated by simply adding trifluoroacetic acid into a chloroform solution of the polymer, and as a result, the multiple colors of fluorescence were sharply changed. Increasing the amount of the acid, the maximum absorption bands of fluorescence spectra were bathochromically shifted from 470 to 570 nm and, then, treating the pyridine as a base, they were recovered. A polymer film containing both the polymer and a photoacid generator (PAG) was prepared by semi‐interpenetrating network polymerization method. When the polymer film was exposed to UV in the presence of PAG through a photomask, well‐resolved fluorescent image patterns were readily obtained. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1228–1233, 2006     

Diels-Alder polymerization of some derivatives of abietic acid

The Diels-Alder polymerization reaction between a bisdiene derived from abietic acid and 4,4′-diphenylmethanedimaleimide (bismaleimide) was studied. The bisdiene was the dehydrodecarboxylation product of abietic acid, denoted here as diabietyl ketone. An insoluble and infusible polymer with high molecular weight was obtained. It is a poly(ketoimide) with hydrophenanthrene moieties in the backbone. The analyses showed that the chemical structure of the polymer was different from that expected. The polymer structural unit was found to contain bismaleimide and diabietyl ketone units not in a molar ratio of 1 : 1, as expected, but in a ratio of 5–6 : 1. The phenomenon was ascribed to the difference between the rates of the two concomitant reactions in the synthesis; the homopolymerization of bismaleimide and the proper Diels-Alder polymerization. The polymer having in structure the monomer units in 1 : 1 ratio was, however, obtained by both the dehydrodecarboxylation of the diacid resulted from the Diels-Alder reaction between abietic acid and 4,4′-diphenylmethanedimaleimide and the polycondensation of the ketone of maleated abietic acid with 4,4′-diaminodiphenylmethane. The monomers and the polymers were investigated by usual physical and chemical methods. The thermal stability of polymers was evaluated by TGA. The synthesized polymers were identical heat-resistant as the crosslinked polymer obtained from 4,4′-diphenylmethanedimaleimide. They were stable in air up to 360°C.     

Synthesis and properties of BCDA‐based polyimide–clay nanocomposites

Bicyclo[2.2.2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic dianhydride (BCDA)‐based polyimide–clay nanocomposites were prepared from their precursor, namely polyamic acid, by a solution‐casting method. The organoclay was prepared by treating sodium montmorillonite (Kunipia F) clay with dodecyltrimethylammonium bromide at 80 °C. Polyamic acid solutions containing various weight percentages of organoclay were prepared from 4,4′‐(4,4′‐isopropylidenediphenyl‐1,1′‐diyldioxy)‐dianiline and BCDA in N‐methyl‐2‐pyrrolidone containing dispersed particles of organoclay at 20 °C. These solutions were cast on a glass plate using a Doctor's blade and then heated subsequently to obtain nanocomposite films. The nanocomposites were characterized using Fourier transform infrared spectroscopy, differential scanning calorimetry, thermal mechanical analysis, dynamic mechanical analysis, polarizing microscopy, scanning electron microscopy, transmission electron microscopy, wide‐angle X‐ray diffraction (WAXD) and thermogravimetric analysis. The glass transition temperature of the nanocomposites was found to be higher than that of pristine polymer. The coefficient of thermal expansion of the nanocomposites decreased with increasing organoclay content. WAXD studies indicated that the extent of silicate layer separation in the nanocomposite films depended upon the organoclay content. Tensile strength and modulus of the nanocomposite containing 1% organoclay were significantly higher when compared to pristine polymer and other nanocomposites. The thermal stability of the nanocomposites was found to be higher than that of pristine polymer in air and nitrogen atmosphere. Copyright © 2007 Society of Chemical Industry     

Polyimidazopyrrolones and related polymers. II. Polyimidazopyrrolones from aromatic dianhydrides and 3,3′-dichloro-5,5′-diaminobenzidine

The preparation of 3,3′-dichloro-5,5′-diaminobenzidine and its polymeric reaction products with pyromellitic dianhydride and 3,4,3′,4′-benzophenonetetracarboxylic dianhydride are described. The soluble amine–acid–amide form of the polymer is stable at higher concentrations than the corresponding polymers from 3,3′-diaminobenzidine or 3,3′,4,4′-tetraaminodiphenyl ether. Infrared spectra indicate that polybenzimidazopyrrolone structure is formed after cure. The preparation and properties of films and glass-reinforced laminates prepared from the polymers are described.     

Preparation of a polyimide nanofiltration membrane for lubricant solvent recovery

Polyimide (PI) membrane has been proven to be an efficient approach for solvent recovery. However, the inherent fragility of the PI membrane limits the range of separation conditions and process economics. In this study, copolyimides were synthesized from 3,3′,4,4′‐benzophenone–tetracarboxylic dianhydride (BTDA) and 4,4′‐biamino‐3,3′‐dimethyldiphenyl–methane (DMMDA) by chemical imidization in a two‐step procedure. Then, a PI nanofiltration (NF) membrane was prepared through a phase‐inversion process for solvent recovery from lube oil filtrates. The results indicated that the immersion of the PI (BTDA–DMMDA) NF membrane in a 1,6‐diaminohexane/ethanol crosslinking agent solution carried on the chemical crosslinking modification, which could effectively improve the solvent resistance of the NF membrane. Moreover, the addition of inorganic salt in the polymer solution further enhanced the solvent resistance and pressure resistance of the membrane, which was favorable for the solvent recovery. The lubricant rejection was above 93%, and the solvent flux was about 30 L m^?2 h^?1 with the NF membrane prepared in optimum conditions, and this membrane showed great potential for future development in the application of solvent recovery from lube oil filtrates. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40338.     

Synthesis and photo-induced transformation of helical aromatic polyamides consisting of axially dissymmetric biphenylene joints and azobenzene segments in the backbone

Wholly aromatic polyamides having a novel helical structure were prepared by the reaction of axially dissymmetric (R)- or (S)-6,6′-dimethylbiphenyl-2,2′-dicarbonyl chloride with aromatic diamines, which are soluble in common solvents such as tetrahydrofuran and N,N-dimethylformamide. Photo-irradiation of a tetrahydrofuran solution of the polymer obtained with 4,4′-diaminoazobenzene induced a change of the helical conformation because of the trans–cis isomerization of the azobenzene units in the polymer chain. No change in the specific rotation of the polymer was observed on heating at 100°C for 4h, indicating thermal stability of its helical structure. CD spectra showed that the helical conformation was maintained in methanesulphonic acid. © 1998 SCI.     

Permselectivities of 2,2′‐dimethyl‐4,4′‐bis(aminophenoxyl)biphenyl diphenyl methane–based aromatic polyamide membranes for aqueous alcohol mixtures in pervaporation and evapomeation

The separation of aqueous alcohol mixtures was carried out by use of a series of novel aromatic polyamide membranes. The aromatic polyamides were prepared by the direct polycondensation of 2,2′‐dimethyl‐4,4′‐bis(aminophenoxyl)biphenyl (DBAPB) with various aromatic diacids, such as terephthalic acid (TPAc), 5‐tert‐butylisophthalic acid (TBPAc), and 4,4′‐hexafluoroisopropylidenedibenzoic acid (FDAc). The pervaporation and evapomeation performance of these novel aromatic polyamide membranes for dehydrating aqueous alcohol solution were investigated. The solubility of ethanol in the aromatic polyamide membranes is higher than that of water, but the diffusivity of water through the membrane is higher than that of ethanol. The effect of diffusion selectivity on the membrane separation performances plays an important role in the evapomeation process. Compared with pervaporation, evapomeation effectively increases the permselectivity of water. Moreover, the effect of aromatic diacids on the polymer chain packing density, pervaporation, and evapomeation performance were investigated. It was found that the permeation rate could be increased by introduction of a bulky group into the polymer backbone. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2688–2697, 2003     

Addition polyimides. I. Kinetics of cure reaction and thermal decomposition of bismaleimides

The thermal polymerization of four structurally different bismaleimide resins, prepared by reacting maleic anhydride with four aromatic diamines, viz., 4,4′-diaminodiphenyl methane, 4,4′-diamino diphenyl ether, 4,4′-diamino diphenyl sulfone, and 3,3′-diamino diphenyl sulfone, was followed by differential scanning calorimetry (DSC). The enthalpy change and the kinetic constants for the polymerization reactions were evaluated from the DSC curves. Thermal stability of the cured polymers was studied by thermogravimetry (TG). The kinetic parameters, viz., activation energy E and preexponential factor A, for the thermal decomposition of the cured bismaleimides were calculated from the TG curves using three nonmechanistic integral equations. The kinetic constants (E and A) follow a trend similar to the thermal stability of the polymers.     

Preparation and properties of organo‐soluble polyimides based on 4,4′‐diamino‐3,3‐dimethyldiphenylmethane and conventional dianhydrides

4,4′‐Diamino‐3,3′‐dimethyldiphenylmethane was used to prepare polyimides in an attempt to achieve good organo‐solubility and light color. Polyimides based on this diamine and three conventional aromatic dianhydrides were prepared by solution polycondensation followed by chemical imidization. They possess good solubility in aprotonic polar organic solvents such as N‐methyl 2‐pyrrolidone, N,N‐dimethyl acetamide, and m‐cresol. Polyimide from 4,4′‐diamino‐3,3′‐dimethyldiphenylmethane and diphenylether‐3,3′,4,4′‐tetracarboxylic acid dianhydride is even soluble in common solvents such as tetrahydrofuran and chloroform. Polyimides exhibit high transmittance at wavelengths above 400 nm. The glass transition temperature of polyimide from 4,4′‐diamino‐3,3′‐dimethyldiphenylmethane and pyromellitic dianhydride is 370°C, while that from 4,4′‐diamino‐3,3′‐dimethyldiphenylmethane and diphenylether‐3,3′,4,4′‐tetracarboxylic acid dianhydride is about 260°C. The initial thermal decomposition temperatures of these polyimides are 520–540°C. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1299–1304, 1999     

Preparation and properties of novel fluorinated polyimides based on 2,2′,6,6′-tetrafluorobenzidine

Fluorinated polyimides were prepared from 2,2′,6,6′-tetrafluorobenzidine and four conventional dianhydride monomers by a solution polycondensation reaction followed by a chemical imidization. Polyimide based on 2,2′,6,6′-tetrafluorobenzidine and hexafluoroisopropylidene bis(3,4-phthalic anhydride) (6FDA) is soluble in organic solvents such as NMP, DMA, DMF, THF, chloroform, and acetone while those based on 2,2′,6,6′-tetrafluorobenzidine and pyromellitic dianhydride (PMDA), benzophenone-3,3′,4,4′-tetracarboxylic acid dianhydride (BTDA), diphenylether-3,3′,4,4′-tetracarboxylic acid dianhydride (ETDA) are not. Polyimide from 2,2′,6,6′-tetrafluorobenzidine and 6FDA possesses high optical transparency at 350–700 nm and has a in-plane refractive index of 1.558 at 632.8 nm. All polyimides exhibit glass transition temperatures above 350°C. They also possess very high thermal stability. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 1605–1609, 1998     

Thermal properties of phosphorylated nanodiamond reinforced polyimides

Recently, the preparation of nanodiamond–polymer composites has attracted the attention of materials scientists due to the unique properties of nanodiamonds. In this study, novel polyimide (PI)/phosphorylated nanodiamonds (PNDs) composites were prepared. PNDs were achieved from the reaction of methylphosphonic dichloride with nanodiamonds in dichloromethane. Precursor of polyimide, which is the poly(amic acid) (PAA), was successfully synthesized with 3,3′, 4,4′‐benzophenonetetracarboxylic dianhydride and 4,4′‐oxydianiline in the solution of N,N‐dimethylformamide. Different ratios of phosphorylated nanodiamond particles were added into PAA solution and four different nanocomposite films were prepared. The amount of PNDs in the composite films was varied from 0 wt% to 3 wt%. The structure, thermal and surface properties of polyimide films were characterized by scanning electron microscopy (SEM), ATR‐FTIR, thermogravimetric analysis (TGA), ultraviolet visible spectroscopy, and contact angle. SEM and FTIR results showed that the phosphorylated nanodiamond and PI/PNDs films were successfully prepared. Phosphorylated nanodiamonds were homogeneously dispersed in the polymer matrix and they displayed good compatibility. TGA results showed that the thermo‐oxidative stability of PI/PNDs films was increased with the increasing amount of phosphorylated nanodiamond. POLYM. COMPOS., 37:2285–2292, 2016. © 2015 Society of Plastics Engineers     

Preparation of polyamides via the phosphorylation reaction. II. Modification of wholly aromatic polyamides with trifunctional monomers

The trifunctional monomers trimesic acid (TMA) and 3,5-diaminobenzoic acid (DAB), each separately and in combination, were used in amounts of 2 to 5 mole-% in order to increase the molecular weight of aromatic polyamides prepared via the Yamazaki phosphorylation reaction. In general, under comparable conditions the use of DAB led to polymer having higher inherent viscosity (IV) values than did TMA. A typical polymer was the polyisophthalamide of 4,4′-methylenedianiline, MDA-I, prepared by the reaction at 100°C of 4,4′-methylenedianiline (MDA) with isophthalic acid (I) in N-methylpyrrolidione (containing 5% dissolved lithium chloride) and employing triphenyl phosphite as condensation agent with pyridine as catalyst. For molar substitutions of 0.0, 2.0, 2.5, and 3.0% of DAB, MDA–I having IV values respectively of 1.1, 1.3, 1.9, and 2.3 was obtained. The latter two samples have IV values in the same range as those obtained for MDA–I prepared from MDA and isophthaloyl chloride in dimethylacetamide (DMAc) via the low-temperature polycondensation method, which prior experience has shown yields polymers that are quite suitable for the spinning of good fibers. At 5 mole-% substitution of DAB, an IV of 3.7 was obtained but a large quantity of gel particles was observed on dissolving the sample in DMAc containing 5% LiCl, indicating that considerable crosslinking had probably occurred. The rod-like polymer poly-p-benzamide (PPB) was prepared in similar fashion to MDA-I from p-aminobenzoic acid and IV values of respectively 1.6, 2.3, 3.8, and 3.9 were obtained when 0.0, 2.0, 2.5, and 3.0 mole-% of mixed trifunctional monomers were present. A solution of the latter sample dissolved in concentrated sulfuric acid contained considerable gel, indicating that crosslinked polymer was probably produced. It would appear that the chain branching approach for producing high molecular weight PPB for spinning to fibers will not prove useful because PPB having an IV value of about 3 to 4 is considered only marginal for the production of commercial-quality fibers (even though PPB of IV value 1.6 can be spun to high-strength/high-modulus fibers) and because the requisite balance of strength and modulus to elongation to break are only obtained for fibers from PPB having an IV value above about 3.5, and preferably about 5 to 6.     

Synthesis and characterization of polyimides and polyamide-imides containing azomethine linkages

Polyimides and polyamide-imides containing azomethine linkages in the polymer backbone have been synthesized from 4,4′-bis(4-isocyanatobenzylidene)-diaminodiphenylether (ODAI), 4,4′-bis(4-isocyanatobenzylidene)-diaminodiphenyl-methane (MADI), 4,4′-bis(4-isocyanatobenzylidene)-diaminodiphenylsulphone (SDAI), pyromellitic dianhydride (PMDA), 3,3′,4,4′-benzophenone tetracarboxylic dianhydride (BTDA), and trimellitic anhydride (TMA), by a one-step process. The diisocyanates ODAI, MDAI and SDAI were prepared from the corresponding diacids, namely, 4,4′-bis(4-carboxybenzylidene)-diaminodiphenylether (ODAA), 4,4′-bis(4-carboxybenzylidene)-diaminodiphenylmethane (MDAA) and 4,4′-bis-(4-carboxybenzylidene)-diaminodiphenylsulphone (SDAA) by a Weinstock-modified Curtius rearrangement method. All the polycondensation reactions were conducted in N-methyl-2-pyrrolidone (NMP) under identical conditions and the polymers obtained were characterized by IR spectroscopy, solution viscosity, elemental analysis, thermogravimetric analysis, differential scanning calorimetry and X-ray diffraction.     

Synthesis and Pyrolysis-Field Ionization Mass Spectrometric Study of an Aromatic Polyamide Having Azo Group in the Main Chain

The reductive coupling of p-nitrobenzoic acid with glucose solution gave 4,4′-azodibenzoic acid and was converted to 4,4′-azodibenzoylchloride using thionyl chloride. This aromatic diacid chloride was condensed with 4,4′-Diaminodiphenyl ether by two different techniques to yield aromatic polyamide. The low temperature polymerization method resulted in comparatively high molecular weight polymer as evidenced by intrinsic viscosity values. The structure of the material was confirmed by IR studies. Detailed pyrolysis-field ionization mass spectral studies carried out indicated two major degradations. In the temperature region (180–200°C), the mass spectrum showed intense peaks at m/z = 166 and 149 which can be explained from the fragmentation of azodicarboxylic acid formed from the polymer. The mass spectrum recorded at 465°C gave clear proof for the structure of the polyamide and also enough evidence was noted for the hydrogenation of the azo group during pyrolysis.     

Preparation of highly H+ permeable sulfonated poly(ether ether ketone) cation exchange membranes and their applications in electro‐generation of thioglycolic acid

BACKGROUND: Sulfonated poly(ether ether ketone) (SPEEK) was successfully synthesized from sulfonated 4,4′‐difluorobenzophenone, 4,4′‐difluorobenzophenone and bisphenol A. SPEEK cation exchange membranes were prepared by the casting method. The composition and morphology of SPEEK were characterized using Fourier transform infrared and ¹H NMR spectroscopies, respectively. The ion exchange capacity (IEC), water uptake and degree of swelling of the membranes were also investigated. SPEEK120 was used as a separator in an electrolysis cell to produce thioglycolic acid (TGA). RESULTS: SPEEK polymerization was carried out at 145 and 175 °C for 10 h. The IEC of the SPEEK membranes was measured as 0.24–2.02 meq g^?1 and the water uptake as 2.26–26.45%. The degree of swelling of the membranes was 1.71–15.28%. TGA was effectively prepared by electro‐reduction of dithioglycolic acid. The current efficiency peaked at 58.31% at room temperature with a current density of 15 mA cm^?2. CONCLUSION: SPEEK120 membrane shows good dimensional stability and H⁺ permeability. Compared to the traditional metal‐reduction method, the current electro‐reduction technique avoids the use of zinc powder and so reduces environmental pollution. Copyright © 2009 Society of Chemical Industry     

Synthesis and characterization of aromatic polyesters containing multiple n-alkyl side chains

A series of 2,2′-disubstituted-4,4′-dihydroxybiphenyl monomers was prepared from 3,4,5-tris(n-alkoxy)benzyl chlorides (n = 5, 6, 8, 10, 12) and tetramethylammonium salt of 4,4′-dihydroxydiphenic acid, which was synthesized from two different 5-step routes. 2,2′-Bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid was synthesized via 5-step route. A series of aromatic polyesters containing multiple alkyl side chains was prepared from the 2,2′-disubstituted-4,4′-dihydroxybiphenyl monomers and 2,2′-bis(trifluoromethyl)-4,4′-biphenyldicarboxylic acid using diisopropylcarbodiimide as a dehydrating agent and 4-(dimethylamino)pyridinium 4-toluenesulfonate as a catalyst at room temperature. Their thermal and solution properties were measured and compared with the polyester without multiple alkyl side chains. The polyesters displayed better solubility in common solvents such as chlorinated solvents and THF but lower thermal stability than the polyester without multiple alkyl side chains. The intrinsic viscosities of the polyesters ranged from 0.68 to 2.53 dL/g and their number-average molecular weights ranged from 19,300 to 61,400. Polyesters containing C5–10 side chains were amorphous while the two polyesters containing C12 side chains crystallized at ?27 and ?31 °C, respectively. The thermal stability of the polyesters decreased as a result of alkyl side chains. The films of polyesters were opaque, indicating that the aromatic backbones and aliphatic side chains underwent phase separation.     

Synthesis and characterization of soluble polyimides and its ultrafiltration membrane performances

Soluble polyimides were synthesized and characterized from two diamines and four dianhydrides by the two- and the one-step method. Most of the polyimides could be soluble by one-step method except α,α′-bis(4-aminophenyl)-1,4-diisopropyl benzene/3,3′,4,4′-benzophenonetetracarboxylic dianhydride system in limited organic solvents. Glass transition temperatures ranged from 186 to 233°C and crystalline melt temperatures were not observed. All the soluble polyimides showed good thermal, mechanical, and electrical properties. The polyimides did not have crystalline structure and limited solubilities. The effective solvent had a medium dispersion component associated with weak polar and hydrogen components. The polymer from one-step polymerization had a narrower molecular weight distribution than the two-step method. Polyimide synthesized with 4,4′-oxydiphthalic anhydride and bis[4-(3-aminophenoxy)phenyl]sulfone by two-step method could only be prepared by the typical phase inversion method. Other membranes except this polyimide membrane could not be prepared by the typical phase-inversion method because of poor solubility about polar solvents. The flux of this ultrafiltration membrane was very high, and this membrane could especially retain polymer having a molecular weight 20,000 to above 90%. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 907–918, 1999     

Preparation and properties of aramids based on naphthalenedicarboxylic acid and their molecular composites with amorphous nylon

Two naphthalene-aromatic polyamides were prepared from 2,6-naphthalenedicarboxylic acid and various aromatic diamines by a modified Higashi phosphorylation reaction. The first polymer, poly(4,4′-diaminobenzanilide-2,6-naphthalamide)^** (DBNA), was synthesized by the reaction of 2,6-naphthalenedicarboxylic acid with 4,4′-diaminobenzanilide. The second polymer, 50/50 copoly(1,4-phenylene/1,4-bis(4′-phenoxy)benzene-2,6-naphthalamide)^*** (PBNA), is a copolymer synthesized using an equimolar ratio of 1,4-phenylene diamine and 1,4-bis(4′-aminophenoxy)benzene. These two polymers have inherent viscosities of 4.17 and 2.32 dL g^-1, respectively, and dissolve in N-methyl-2-pyrrolidone (NMP)containing LiCl. Highstrength films were obtained by casting from these polymer solutions. Blends of DBNA/amorphous nylon and of PBNA/amorphous nylon were prepared by rapidly precipitating the ternary NMP solution into deionized water, and hot-pressing to films at 185°C. The compatibility, morphology, and mechanical properties were investigated by dynamic mechanical analysis (DMA), scanning electron microscopy (SEM), and tensile tests. The results revealed that both DBNA and PBNA were partially compatible with amorphous nylon. DBNA formed microfibrils in the amorphous nylon matrix, and its mechanical properties, tensile strength and modulus, improved with increasing DBNA content. PBNA had no reinforcing effect, perhaps because it did not form microfibrils in the amorphous nylon matrix.