Synthesis of polypyridazinophthalazinediones from diacetylphthalic acids and aromatic dihydrazines

The cyclopolycondensation of two diacetylphthalic acids with aromatic dihydrazines produced a series of new high-molecular-weight polypyridazinophthalazinediones with pendant methyl groups. The polymers were best prepared in m-cresol at 100°C and, after isolation, were readily soluble in dichloroacetic acid and m-cresol. Clear yellow films could be cast from m-cresol solutions and thermogravimetric analysis of all the polymers showed a 10% weight loss at 455–;505°C in nitrogen.     

Synthesis of aromatic polyamide-phthalimidines from chloroformylphthalides and aromatic diamines

New polymer-forming monomers, 3-benzylidene-5-chloroformylphthalide and 3-benzylidene-6-chloroformylphthalide, were synthesized by the Perkin reaction of trimellitic anhydride with phenylacetic acid, followed by chlorination. The polycondensation of these monomers with aromatic diamines in N-methyl-2-pyrrolidone at 200°C afforded aromatic polyamide-phthalimidines having inherent viscosities of 0.2-0.5 dL/g. All the polymers were readily soluble in m-cresol, pyridine, dimethylformamide, and dimethyl sulfoxide. Glass transition temperatures of some of the polymers were in the range of 255–282°C. The polyamide-phthalimidines began to lose weight at around 300°C in both air and nitrogen atmospheres, with 10% weight losses being recorded at 435–475°C in nitrogen by thermogravimetry.     

Poly(enamine-ketones) from aromatic diacetylenic diketones and aromatic diamines

Novel poly(enamine-ketones) were prepared with inherent viscosities as high as 1.99 dL/g using the Michael-type addition of various diamines to 1,1′-(1,3 or 1,4-phenylene)bis(3-phenyl-2-propyn-1-one) in m-cresol at 60–130°C. Tough, clear, amber films with tensile strengths of 12, 400 psi and tensile moduli of 397, 000 psi were cast from solutions of the polymers in chloroform. The polymers exhibited T_gs as high as 235°C and weight losses of 14% after aging at 232°C in circulating air for 60 h. The synthesis and characterization of several poly(enamine-ketones) are discussed.     

Syntheses of polyamides and polypyrrolones from 2,2′-disubstituted bis(3-buten-4-olides) and diamines

The ring-opening polyaddition of 2,2′-disubstituted bis(3-buten-4-olides) with aliphatic diamines in m-cresol at room temperature afforded in quantitative yields polyamides with a pendant ketone moiety having inherent viscosities of up to 0.7. On the other hand, the polymerization in m-cresol at 80°C with acidic catalysts and at 160°C without any catalyst yielded directly polypyrrolones, a novel class of polyheterocycles. The cyclodehydration of the open-chain polyamides to polypyrrolones was also achieved by simply treating the polyamide films with methanolic hydrochloric acid at room temperature. Both of the polymers were generally soluble in hot polar solvents such as dimethylformamide, m-cresol, and nitrobenzene. The polypyrrolones began to lose weight gradually at around 250°C in nitrogen as determined by thermogravimetric analysis, while the thermograms in air showed an appreciable weight increase at about 230°C.     

Synthesis of polypyridazinophthalazinediones from dibenzoylphthalic acids and aromatic dihydrazines

A novel class of polypyridazinophthalazinediones has been synthesized by the solution cyclopolycondensation in m-cresol of dibenzoylphthalic acids with aromatic dihydrazines such as bis(4-hydrazinophenyl)methane and bis(4-hydrazinophenyl) sulfone. The polyheterocycles derived from 4,6-dibenzoylisophthalic acid, which had inherent viscosities of up to 0.5, were soluble in m-cresol and hot dichloroacetic acid, whereas the polymers from 2,5-dibenzoylterephthalic acid were practically insoluble in organic solvents. Thermogravimetric analyses showed that all the polymers underwent weight losses of 10% at 490–520°C in both air and nitrogen.     

Preparation and properties of aromatic polypyrazoles from branched bis-β-diketones and aromatic dihydrazines

Aromatic polypyrazoles were prepared by the cyclopolycondensation of branched bis-β-diketones with aromatic dihydrazines. The polymerizations were carried out at 100–150°C in m-cresol or a polar aprotic solvent like dimethyl sulfoxide to produce polymers with inherent viscosities up to 0.98 dl/g. These polypyrazoles were readily soluble in a wide range of solvents that included chloroform and exhibited 10% weight losses between 380 and 425°C in air and 370 and 500°C in nitrogen.     

Synthesis of polyamides by ring-opening polyaddition of 4,4′-disubstituted bis(3-buten-4-olide) with aliphatic diamines

An investigation of the reaction of 4-phenyl-3-buten-4-olide with benzylamine was conducted as a model for the polymerization, and some ethers and acidic solvents were found to be favorable reaction media for formation of the ring-opened amide as the sole product. By using m-cresol as the polymerization medium, linear polyamides having inherent viscosities up to 0.67 were readily prepared by the ring-opening polyaddition of 4,4′-oxydi-p-phenylenebis(3-buten-4-olide) with aliphatic diamines at room temperature. These polymers were soluble in m-cresol and gave transparent, flexible films by the solution casting technique. They did not show any melt temperature, and began to decompose at around 200°C, both in air and under nitrogen.     

A facile synthesis of polyamides from aromatic diisocyanates and dicarboxylic acid catalyzed by Lewis acids

Aromatic polyamides were prepared by an AlCl₃ or HCl-catalyzed polymerization of toluene diisocyanate or methylenebis(phenyl isocyanate) with adipic acid at low temperatures (≤100°C) in a short reaction time (3–4 h). The intrinsic viscosity of the polymers was approximately 1.1 dL/g as determined at 25°C with m-cresol as solvent, indicating that the polyamides obtained by this method have relatively high molecular weights. The polymers exhibit high glass transition temperatures and good thermal stability.     

Poly(enamine-ketones) from hydrogen-terminated aromatic dipropynones and aromatic diamines

Poly(enamine-ketones) were prepared by the nucleophilic (Michael-type) addition of various aromatic diamines to 1,1′-(1,3- or 1,4-phenylene)bis(2-propyn-1-one)(1,3 or 1,4-PPO) in m-cresol at 5–23°C. The low molecular weight polymers (inherent viscosity of 0.25 dL/g) exhibited limited solubility in organic solvents. Glass transition temperatures were generally undetectable by differential scanning calorimetry while polymer decomposition temperatures (10% weight loss), as measured by thermogravimetric analysis, were observed from 355 to 419°C. Polymers prepared from 1,4-PPO were semi-crystalline as shown by wide-angle X-ray diffraction. The poly(enamine-ketone) structure was confirmed by matching infrared spectral characteristics of the polymers with those of well-characterized model enamine ketones.     

Synthesis of polydihydropyridazinones from bis(3-benzoylpropionic acids) and aromatic dihydrazines

A new class of polydihydropyridazinones has been synthesized by the solution cyclopolycondensation in m-cresol of 4,4′-oxy- and 4,4′-ethylenebis(3-benzoylpropionic acids) with aromatic dihydrazines such as bis(4-hydrazinophenyl) sulfone and bis(4-hydrazinophenyl)methane. The polymers having inherent viscosities of 0.2–0.4 were highly soluble in a wide range of solvents including m-cresol, N,N-dimethylacetamide, and pyridine. Thermogravimetric analysis of the polydihydropyridazinones showed initial weight losses commencing at 290–350°C in both air and nitrogen.     

Preparation and properties of aromatic polyamides from 1,4-bis(p-carboxyphenoxy)naphthyl and aromatic diamines

A new aromatic dicarboxylic acid, 1,4-bis (p-carboxyphenoxy)naphthyl ( 3 ), was synthesized by the reaction of p-fluorobenzonitrile with 1,4-naphthalenediol, followed by hydrolysis. Aromatic polyamides having inherent viscosities of 1.27–2.22 dL/g were prepared by the triphenyl phosphite activated polycondensation of diacid 3 with various aromatic diamines. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents including N,N-dimethyl-acetamide (DMAc), N-methyl-2-pyrrolidone (NMP), and m-cresol. Transparent, tough, and flexible films of these polymers could be cast from the DMAc or NMP solutions. The cast films had tensile strengths ranging from 64–104 MPa, elongations-at-break from 6 to 10%, and initial moduli from 1.52 to 2.14 GPa. These polyamides had glass transition temperatures in the range of 195 to 240°C. Almost all polymers were thermally stable up to 400°C, with 10% weight loss being recorded above 480°C in air and nitrogen atmospheres. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 2273–2280, 1997     

Synthesis and characterization of soluble aromatic polyurea-amides from new N,N′--dimethyl-N,N′-bis(aminophenyl)ureas and aromatic dicarboxylic acid chlorides

Aromatic polyurea-amides having inherent viscosities of 0.36–0.67 dL/g were synthesized by the low temperature solution polycondensation of new N,N′-dimethyl-N,N′-bis(aminophenyl)ureas with various aromatic dicarboxylic acid chlorides. All the polymers were amorphous, and most of them were soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide (DMAc), m-cresol, and pyridine. Some of the polymers could be cast from the DMAc solutions into transparent and flexible films having good tensile properties. The glass transition temperatures of the polyurea-amides obtained from the bis(4-aminophenyl)-substituted ureas were 244–272°C. The temperatures of 10% weight loss under nitrogen of the polymers were in the range of 430 and 480°C. © 1995 John Wiley & Sons, Inc.     

Synthesis and characterization of novel aromatic polyamides from 3,4-bis(4-aminophenyl)-2,5-diphenylpyrrole and aromatic diacid chlorides

A new polymer-forming monomer, 3,4-bis(4-aminophenyl)-2,5-diphenylpyrrole, was synthesized in three steps starting from 4′-nitrodeoxybenzoin. Tetraphenylpyrrole-containing aromatic polyamides and copolyamides were prepared from the diamine with various aromatic diacid chlorides and from a mixture of the diamine and 4,4′-oxydianiline with terephthaloyl chloride, respectively. The resultant polymers had inherent viscosities in the 0.3–1.8 dL/g range and were generally soluble in various organic solvents including N,N-dimethylacetamide and m-cresol. They have glass transition temperatures in the range of 306–333°C and showed no weight loss below 380°C in both air and nitrogen atmospheres.     

Synthesis and characterization of N-phenylated aromatic polyamides from N-silylated dianilino compounds and aromatic diacid chlorides

N-Phenylated aromatic polyamides of high molecular weights were synthesized by the hightemperature solution polycondensation of N,N′ -di(trimethylsilyl)-substituted dianilino compounds derived from p-dianilinobenzene, bis(4-anllinophenyl) ether, and α,α′-dianilino-p-xylene, with isophthaloyl and terephthaloyl chloride. Almost all of the N-phenylated polyamides were amorphous, and soluble in a variety of organic solvents including dimethylformamide, m-cresol, and chloroform. Transparent and flexible films of these polymers could be cast from the dimethylformamide solutions. Four wholly aromatic polyamides had glass transition temperatures in the range of 195–255°C, and began to lose weight around 400°C in air.     

Polyphenylquinoxalines with high glass transition temperatures via highly fused aromatic tetraamines

A series of polyphenylquinoxalines has been synthesized by the reaction of p,p′-oxydibenzil with aromatic tetraamines containing varying numbers of fused rings. It was found that the glass transition temperatures of the resultant polymers increased as the the number of adjacent fused rings in the polymers was increased. This provided the basis for achieving glass transition temperatures for the polymers in excess of 400°C, substantially higher than the state-of-the art polyphenylquinoxalines. All of the polymers displayed both the good thermal stability and the solubility in m-cresol characteristic of the polyphenylquinoxaline family of polymers.     

Preparation and properties of aromatic polyesters and copolyesters containing phenylindane unit

Aromatic polysters and copolyesters of high molecular weights with phenylindane units were prepared from combinations of 3-(4-hydroxyphenyl)-1,1,3-trimethyl-5-indanol and bisphenol A with isophthaloyl and terephthaloyl chloride by two-phase polycondensation in a nitrobenzene-water system with various phase-transfer catalysts. The phenylindane-containing polyesters and copolyesters were amorphous and readily soluble in a wide range of solvents that included chloroform, m-cresol, tetrahydrofuran, and dimethylformamide. The glass transition temperatures of the phenylindane-derived polyisophthalate and polyterephthalate were 235 and 253°C, respectively, which were higher than those of the corresponding bisphenol A analogs by some 50°C. These polymers began to lose weight around 400°C in air and nitrogen atmospheres.     

Synthesis and characterization of optically active aromatic polyimides derived from 2,2′-bis(2-trifluoro- 4-aminophenoxy)-1,1′-binaphthyl and aromatic tetracarboxylic dianhydrides

Optically active 2,2′-bis(2-trifluoro-4-aminophenoxy)-1,1′-binaphthyl and its corresponding racemate were prepared by a nucleophilic substitution reaction of 1,1′-bi-2-naphthol with 2-chloro-5-nitrotrifluorotoluene and subsequently by the reduction of the resulting dinitro compounds. A series of optically active and optically inactive aromatic polyimides also were prepared therefrom. These polymers readily were soluble in common organic solvents such as pyridine, N,N′-dimethylacetamide, and m-cresol and had glass-transition temperatures of 256 ∼ 278 °C. The specific rotations of the chiral polymers ranged from 167 ∼ 258°, and their chiroptical properties also were studied. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 4536–4540, 1999     

Synthesis and characterization of aromatic poly(ether sulfone)s containing pendant sodium sulfonate groups

Poly(ether sulfone)s containing pendant sodium sulfonate groups were prepared by the aromatic nucleophilic substitution reaction of 4,4′-dichlorodiphenylsulfone ( 1 ) and sodium 5,5′-sulfonylbis (2-chlorobenzenesulfonate) ( 2 ) with bisphenols ( 3 ) in the presence of potassium carbonate in N,N-dimethylacetamide. A new monomer 2 containing the sodium sulfonate groups was synthesized by the sulfonation of 1 with fuming sulfuric acid. The polycondensation proceeded smoothly at 170°C and produced the desired poly(ether sulfone)s containing the sodium sulfonate with inherent viscosities up to 1.2 dL/g. The polymers were quite soluble in strong acid, dipolar aprotic solvents, m-cresol, and dichloromethane. The thermogravimetry of the polymers showed excellent thermal stability, indicating that 10% weight losses of the polymers were observed in the range above 460°C in nitrogen atmosphere. Both the glass transition temperatures and hydrophilicity of the polymers increased with increasing their concentrations of sodium sulfonate groups. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of new soluble aromatic polyamides from diaminotetraphenylimidazolin-2-one and various aromatic dicarboxylic acid chlorides

Novel aromatic polyamides, having inherent viscosities of 0.76-2.31 dL/g, were synthesized by the low temperature solution polycondensation of a new highly phenylated diamine monomer having an imidazolinone group, 1,3-bis(4-aminophenyl)-4,5-diphenylimidazoline-2-one (TPIDA), with various aromatic diacid chlorides. All the polymers were amorphous, and most of the polyamides were readily soluble in organic solvents such as N-methyl–2-pyrrolidone, N,N-dimethylacetamide (DMAc), and m-cresol. Flexible and tough films could be prepared from the DMAc solutions of these soluble aromatic polyamides. The glass transition temperatures and 10% weight loss temperatures under nitrogen of the polyamides were in the range of 275–315°C and 430–505°C, respectively. © 1995 John Wiley & Sons, Inc.     

Synthesis and characterization of phenyl-pendant aromatic polythiazoles from bis-α-bromophenylacetyl compounds and dithioamides

Novel phenyl-pendant aromatic polythiazoles having inherent viscosities of 0.3–1.3 dL/g were synthesized by the solution polycondensation of bis[4-(α-bromophenylacetyl)phenyl] ether with aromatic dithioamides or dithiooxamide in dimethylformamide at 60°C. The polythiazole having m-phenylene linkage was readily soluble in chloroform and m-cresol, and transparent flexible film could be cast from the chloroform solution. Glass transition temperatures of these polythiazoles were in the range of 210–250°C. They started to decompose at about 500°C in air with 10% weight loss being recorded at around 570°C.