Synthesis and characterization of new highly organosoluble poly(etherimide)s derived from 1,1‐bis{4‐[4‐(3,4‐dicarboxyphenoxy)phenyl]‐4‐phenylcyclohexane} dianhydride

A new bulky pendent bis(ether anhydride), 1,1‐bis[4‐(4‐dicarboxyphenoxy)phenyl]‐4‐phenylcyclohexane dianhydride, was prepared in three steps, starting from the nitrodisplacement of 1,1‐bis(4‐hydroxyphenyl)‐4‐phenylcyclohexane with 4‐nitrophthalonitrile to form bis(ether dinitrile), followed by alkaline hydrolysis of the bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). A series of new poly(ether imide)s were prepared from the bis(ether anhydride) with various diamines by a conventional two‐stage synthesis including polyaddition and subsequent chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.50–0.73 dL g^?1. The gel permeation chromatography measurements revealed that the polymers had number‐average and weight‐average molecular weights of up to 57,000 and 130,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility in comparison with the other polyimides derived from adamantane, norbornane, cyclododecane, and methanohexahydroindane and were readily dissolved in various solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. These polymers had glass‐transition temperatures of 226–255 °C. Most of the polymers could be dissolved in chloroform in as high as a 30 wt % concentration. Thermogravimetric analysis showed that all polymers were stable up to 450 °C, with 10% weight losses recorded from 458 to 497 °C in nitrogen. These transparent, tough, and flexible polymer films could be obtained by solution casting from DMAc solutions. These polymer films had tensile strengths of 79–103 MPa and tensile moduli of 1.5–2.1 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2066–2074, 2002     

Hyperbranched poly(ether–urea)s using AB2‐type blocked isocyanate monomer and azide monomer: Synthesis,characterization, reactive end functionalization,and copolymerization with AB monomer

3,5‐bis(4‐aminophenoxy)phenyl phenylcarbamate—a novel AB₂‐type blocked isocyanate monomer and 3,5‐bis{ethyleneoxy(4‐aminophenoxy)}phenyl carbonyl azide—a novel AB₂‐type azide monomer were synthesized in high yield. Step‐growth polymerization of these monomers were found to give a first example of hyperbranched poly (aryl‐ether‐urea) and poly(aryl‐alkyl‐ether‐urea). Molecular weights (M_w) of the polymer were found to vary from 1,858 to 52,432 depending upon the monomer and experimental conditions used. The polydispersity indexes were relatively narrow due to the controlled regeneration of isocyanate functional groups for the polymerization reaction. The degree of branching (DB) was determined using ¹H‐NMR spectroscopy and the values ranged from 87 to 54%. All the polymers underwent two‐stage decomposition and were stable up to 300 °C. Functionalized end‐capping of poly(aryl‐ether‐urea) using phenylchloroformate and di‐t‐butyl dicarbonate (Boc)₂O changed the thermal properties and solubility of the polymers. Copolymerization of AB₂‐type blocked isocyante monomer with functionally similar AB monomer were also carried out. The molecular weights of copolymers were found to be in the order of 6 × 10⁵ with narrow dispersity. It was found that the T_g's of poly(aryl‐alkyl‐ether‐urea)s were significantly less (46–49 °C) compared to poly(aryl‐ether‐urea)s. Moreover the former showed melting transition at 154 °C, which was not observed in the latter case. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2959–2977, 2007     

Aromatic poly(1,3,4‐oxadiazole)s and poly(amide‐1,3,4‐oxadiazole)s containing ether sulfone linkages

Polyhydrazides and poly(amide‐hydrazide)s were prepared from two ether‐sulfone‐dicarboxylic acids, 4,4′‐[sulfonylbis(1,4‐phenylene)dioxy]dibenzoic acid and 4,4′‐[sulfonylbis(2,6‐dimethyl‐1,4‐phenylene)dioxy]dibenzoic acid, or their diacyl chlorides with terephthalic dihydrazide, isophthalic dihydrazide, and p‐aminobenzhydrazide via a phosphorylation reaction or a low‐temperature solution polycondensation. All the hydrazide polymers were found to be amorphous according to X‐ray diffraction analysis. They were readily soluble in polar organic solvents such as N‐methyl‐2‐pyrrolidone and N,N‐dimethylacetamide and could afford colorless, flexible, and tough films with good mechanical strengths via solvent casting. These hydrazide polymers exhibited glass‐transition temperatures of 149–207 °C and could be thermally cyclodehydrated into the corresponding oxadiazole polymers in the solid state at elevated temperatures. Although the oxadiazole polymers showed a significantly decreased solubility with respect to their hydrazide prepolymers, some oxadiazole polymers were still organosoluble. The thermally converted oxadiazole polymers had glass‐transition temperatures of 217–255 °C and softening temperatures of 215–268 °C and did not show significant weight loss before 400 °C in nitrogen or air. For a comparative study, related sulfonyl polymers without the ether groups were also synthesized from 4,4′‐sulfonyldibenzoic acid and the hydrazide monomers by the same synthetic routes. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2271–2286, 2001     

A new category of thermally stable poly(ether amide ether imide)s with increased solubility

Two new poly(ether amide ether imide)s (PEAEIs) were prepared from a new diamine (DA) containing ether, aliphatic, amide, naphthyl and pyridine functional groups that resulted flexible and thermally stable ultimate polymers. The DA was synthesized via two steps, starting from nucleophilic substitution reaction of 1,8‐diamino‐3,6‐dioxaoctane with 6‐chloronicotinoyl chloride in the presence of propylene oxide which, afforded dichloro‐diamide (DCDA) compound. In the second step for the preparation of DA, reaction of DCDA compound with 5‐amino‐1‐naphthol in the presence of K₂CO₃ was achieved. The new DA was then polycondensed with 2,2'‐bis‐(3,4‐dicarboxyphenyl) hexafluoropropane dianhydride and pyromellitic dianhydride to produce PEAEIs. The precursor, monomer and obtained polymers were entirely characterized by FT‐IR and ¹H‐NMR spectroscopy and elemental analysis techniques. The physical properties of the polymers including solubility, thermal behavior, thermal stability, inherent viscosity, morphology and mechanical properties were studied. The new PEAEIs exhibited favorable balance of physical and thermal properties, and their solubility was improved without sacrificing their thermal stability. Copyright © 2013 John Wiley & Sons, Ltd.     

Synthesis of poly(ether ketone amide)s containing 4‐aryl‐2,6‐ diphenylpyridine moieties by a heterogeneous palladium‐catalyzed polycondensation of aromatic diiodides,aromatic diamines,and carbon monoxide

New aromatic poly(ether ketone amide)s containing 4‐aryl‐2,6‐diphenylpyridine units were prepared by the heterogeneous palladium‐catalyzed carbonylative polymerization of aromatic diiodides with ether ketone units, aromatic diamines bearing pyridine groups, and carbon monoxide. Polymerizations were performed in N,N‐dimethyl‐ acetamide (DMAc) at 120°C in the presence of a magnetic nanoparticles‐supported bidentate phosphine palladium complex [Fe₃O₄@SiO₂‐2P‐PdCl₂] as catalyst with 1,8‐diazabicycle[5,4,0]‐7‐undecene (DBU) as base and generated poly(ether ketone amide)s with inherent viscosities up to 0.79 dL/g. All the polymers were soluble in many organic solvents. These polymers showed glass transition temperatures between 219°C and 257°C and 10% weight loss temperatures ranging from 467°C to 508°C in nitrogen. These polyamides could be cast into transparent, flexible, and strong films from DMAc solution with tensile strengths of 86.4 to 113.7 MPa, tensile moduli of 2.34 to 3.19 GPa, and elongations at break of 5.2% to 6.9%. These polymers also exhibited good optical transparency with an ultraviolet‐visible absorption cut‐off wavelength in the 371 to 384‐nm range. Importantly, the new heterogeneous palladium catalyst can easily be recovered from the reaction mixture by simply applying an external magnet and recycled at least 8 times without significant loss of activity. Our catalytic system not only avoids the use of an excess of PPh₃ and prevents the formation of palladium black, but also solves the basic problems of palladium catalyst recovery and reuse.     

Synthesis of novel poly(aryl ether amide)s containing the phthalazinone moiety

Two novel heterocyclic diamine monomers: 1,2-dihydro-2-(4-aminophenyl)-4-[ 4-( 4-aminophenoxy) phenyl ]-(2H )-phtha-lazin-1-one and 1, 2-dihydro-2-( 4-aminophenyl )-4-[ 4-( 4-aminophenoxy) -3, 5-dimethylphenyl ] - (2H) -phthalazin-1-one were successfully synthesized using readily available heterocyclic bisphenol-like monomers through two steps in high yield. A series of novel poly( aryl ether amide)s containing the phthalazinone moiety with inherent viscosities of 1.16-1.67 dL/g were prepared by the direct polymerization of the novel diamines and aromatic dicarboxylic acids using triphenyl phosphite and pyridine as condensing agents. The polymers were readily soluble in a variety of solvents such as N, N-dimethyl-formamide (DMF), N,N-dimethylacetamide (DMAc), dimethylsulfoxide ( DMSO ), N-methyl-2-pyrrolidinone (NMP), and pyridine. The polymers had high glass transition temperatures (Tg) in the 291-329℃ range.     

Synthesis of aromatic poly(ether amide amide ether ketone ketone)s by electrophilic Friedel–Crafts solution polycondensation

A new monomer, N,N′‐bis(4‐phenoxybenzoyl)‐p‐phenylenediamine (BPBPPD), was prepared by the condensation of p‐phenylenediamine with 4‐phenoxybenzoyl chloride in N,N‐dimethylacetamide (DMAc). Novel aromatic poly(ether amide amide ether ketone ketone)s (PEAAEKKs) were synthesized by electrophilic Friedel–Crafts solution copolycondensation of BPBPPD with a mixture of terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC), over a wide range of TPC/IPC molar ratios, in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The influences of reaction conditions on the preparation of polymers were examined. The polymers obtained were characterized by different physico–chemical techniques such as FT‐IR, Differential scanning calorimetry (DSC), Thermogravimetric analysis (TGA), and wide angle X‐ray diffraction (WAXD). The polymers with 70–100 mol% IPC are semicrystalline and have remarkably increased T_gs over commercially available poly(ether ether ketone) (PEEK) and poly(ether ketone ketone) (PEKK) due to the incorporation of amide groups in the main chain. The polymers with 70–80 mol% IPC had not only high T_gs of 209–213°C, but also moderate T_ms of 339–348°C, which are suitable for melt processing. The polymers with 70–80 mol% IPC had tensile strengths of 107.5–109.8 MPa, Young's moduli of 2.53–2.69 GPa, and elongations at break of 9–11% and exhibited high thermal stability and good resistance to organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.     

Synthesis and characterization of fluorinated poly(aryl ether ketone)s containing 1,4-naphthalene moieties

The new monomer 2,2-bis[4-(4-{4-fluorobenzoyl}-1-naphthoxy)phenyl]hexafluoropropane ( 2 ) was synthesized in a two-step reaction sequence. 2,2-his[4-(1-naphthoxy)phenyl]-hexafluoropropane ( 1 ) was prepared using the Ullmann ether synthesis reaction of 4,4-(hex-afluoroisopropylidiene)diphenol with 1-bromonaphthalene. Friedel-Crafts acylation of 1 with 4-fluorobenzoyl chloride in methylene chloride containing dimethylsulfone selectively afforded 2 in 82% yield. The polycondensation of 2 with various bisphenols in DMAc in the presence of an excess of potassium carbonate as a condensation reagent was carried out at 165°C to quantitatively afford the corresponding fluorinated poly(aryl ether ketone)s containing 1,4-naphthalene moieties. Thermal analysis of the polymers showed them to have T_gs ranging from 194 to 230°C and to be thermally stable in air up with initial weight losses at about 500°C. In addition, these novel polymers exhibited excellent solubility in organic solvents including NMP, DMAc, and chloroform. © 1997 John Wiley & Sons, Inc.     

Synthesis,characterization, and comparison of properties of new fluorinated poly(arylene ether)s containing phthalimidine moiety in the main chain

Four new poly(arylene ether)s have been prepared by the reaction of N‐phenyl‐3,3‐bis(4‐hydroxyphenyl)phthalimidine (PA) with four different perfluoroalkylated monomers namely 1,3‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) benzene, 4,4′‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) biphenyl, 2,6‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) pyridine, and 2,5‐bis(4′‐fluoro‐3′‐trifluoromethyl benzyl) thiophene. The poly(arylene ether)s were characterized by different spectroscopic, thermal, mechanical, and electrical techniques. The poly(arylene ether) containing quadriphenyl unit in the main chain showed very high glass transition temperature of 291°C and outstanding thermal stability upto 556°C for 10% weight loss under a 4:1 nitrogen:oxygen mixture. The polymers were soluble in a wide range of organic solvents. Transparent thin films of these polymers exhibited tensile strengths upto 75 MPa and elongation at break upto 32%. The films of these polymers showed low water absorption of 0.26%. Copyright © 2009 John Wiley & Sons, Ltd.     

Synthesis and characterization of novel poly(amide‐imide)s containing 1,3‐diamino mesitylene moieties

A series of poly(amide‐imide)s were prepared using a new monomer, 1,3‐bis(trimellitimido)‐2,4,6‐trimethyl benzene (BTB), with four different diamines: 1,4‐phenylene diamine (PDA), 2,4‐diamino mesitylene (DAM), 2,2′‐dimethyl‐4,4′‐diamino biphenyl (DMDB), and 2,2′‐bis(trifluoromethyl)‐4,4′‐diamino biphenyl (TFDB). They were prepared by the condensation method in N‐methyl‐2‐pyrrolidinone (NMP) solvent using triphenyl phosphate and pyridine as condensing agents. The synthesized poly(amide‐imide)s were characterized by Fourier transform infrared and ¹H NMR techniques. Films were prepared and characterized using DSC, thermogravimetric analysis (TGA), a prism coupler, and a film dielectric property analyzer. DSC measurement showed that the glass‐transition temperatures of the polymers were in the range of 259–327 °C. TGA analysis showed 5% weight loss, in the range of 472–514 °C. The refractive index varied from 1.6004 to 1.6586 in the following increasing order: BTB‐TFBM < BTB‐DAM < BTB‐DMDB < BTB‐PDA. For the poly(amide‐imide) films, the birefringence varied in the range of 0.0319–0.0580, in the following increasing order: BTB‐DAM < BTB‐TFBM < BTB‐DMDB < BTB‐PDA. The capacitance method showed that the dielectric constant of poly(amide‐imide) varied with the diamine structure; no difference was found by the optical method. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 137–143, 2004     

Synthesis and characterization of new soluble poly(amide‐imide)s derived from 2,2‐bis[4‐(4‐trimellitimidophenoxy)phenyl]hexafluoropropane

A series of new soluble poly(amide‐imide)s were prepared from the diimide‐dicarboxylic acid 2,2‐bis[4‐(4‐trimellitimidophenoxy)phenyl]hexafluoropropane with various diamines by direct polycondensation in N‐methyl‐2‐pyrrolidinone containing CaCl₂ with triphenyl phosphite and pyridine as condensing agents. All the polymers were obtained in quantitative yields with inherent viscosities of 0.52–0.86 dL · g^?1. The poly(amide‐imide)s showed an amorphous nature and were readily soluble in various solvents, such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, pyridine, and cyclohexanone. Tough and flexible films were obtained through casting from DMAc solutions. These polymer films had tensile strengths of 71–107 MPa and a tensile modulus range of 1.6–2.7 GPa. The glass‐transition temperatures of the polymers were determined by a differential scanning calorimetry method, and they ranged from 242 to 279 °C. These polymers were fairly stable up to a temperature around or above 400 °C, and they lost 10% of their weight from 480 to 536 °C and 486 to 537 °C in nitrogen and air, respectively. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3498–3504, 2001     

Synthesis of new fluorinated aromatic poly (ether ketone amide)s containing cardo structures by a heterogeneous palladium‐catalyzed carbonylative polycondensation

New fluorinated aromatic poly (ether ketone amide)s containing cardo structures were prepared by a heterogeneous palladium‐catalyzed polycondensation of fluorinated aromatic diiodides with ether ketone units, aromatic diamines containing cardo groups, and CO. Polymerizations were conducted in N,N‐dimethylacetamide at 120°C using 6 mol% of magnetic nanoparticles‐supported bidentate phosphine palladium (II) complex [Fe₃O₄@SiO₂‐2P‐PdCl₂] as catalyst and 1,8‐diazabicyclo[5,4,0]‐7‐undecene as base and resulted in fluorinated cardo poly (ether ketone amide)s with inherent viscosities up to 0.75 dL/g. All the polymers were readily soluble in many organic solvents and could afford transparent, flexible, and strong films by solution casting. These polymers showed good thermal stability with the glass transition temperature of 237°C–258°C, the temperature at 5% weight loss of 462°C–477°C in nitrogen. These polymer films also exhibited good mechanical properties, excellent electrical and dielectric performance, and high optical transparency. The incorporation of bulky fluorinated groups and cardo structures into polymer backbone has played an important role in the improvement of solubility, dielectric performance, and optical properties. Importantly, the heterogeneous palladium catalyst can easily be recovered from the reaction mixture by simply applying an external magnet and recycled up to 7 times without significant loss of catalytic activity.     

Direct copolymerization of sulfonated poly(phthalazinone arylene ether)s for proton‐exchange‐membrane materials

Sulfonated poly(phthalazinone ether ketone) (SPPEK) copolymers and sulfonated poly(phthalazinone ether sulfone) (SPPES) copolymers containing pendant sodium sulfonate groups were prepared by direct copolymerization. The reaction of disodium 3,3′‐disulfonate‐4,4′‐difluorobenzophenone (SDFB‐Na), 4,4′‐difluorobenzophenone (DFB), and 4‐(4‐hydroxyphenyl)‐1(2H)‐phthalazinone (DHPZ) at 170 °C in N‐methyl‐2‐pyrrolidione containing anhydrous potassium carbonate gave SPPEKs. SPPESs were similarly obtained with 3,3′‐disulfonate‐4,4′‐difluorophenyl sulfone, 4‐fluorophenyl sulfone (DFS), and DHPZ as monomers. The sulfonic acid groups, being on deactivated positions of the polymer backbone, were expected to be hydrolytically more stable than postsulfonated polymers. Fourier transform infrared and ¹H NMR were used to characterize the structures and degrees of sulfonation of the sulfonated polymers. Membrane films of SPPEKs with SDFB‐Na/DFB molar feed ratios of up to 60/40 and SPPESs with sulfonated 4‐fluorophenyl sulfone/DFS molar feed ratios of up to 50/50 were cast from N,N‐dimethylacetamide polymer solutions. Membrane films in acid form were then obtained by the treatment of the sodium‐form membrane films in 2 N sulfuric acid at room temperature. An increase in the number of sulfonate groups in the copolymers resulted in an increased glass‐transition temperature and enhanced membrane hydrophilicity. The sodium‐form copolymers were thermally more stable than their acid forms. The proton conductivities of the acid‐form copolymers with sulfonated monomer/unsulfonated monomer molar feed ratios of 0.5 and 0.6 were higher than 10^?2 S/cm and increased with temperature; they were less temperature‐dependent than those of the postsulfonated products. SPPESH‐50 showed higher conductivity than the corresponding postsulfonated poly(phthalazinone ether sulfone). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 2731–2742, 2003     

Synthesis and characterization of new highly organosoluble poly(ether imide)s based on 3,3′,5,5′‐tetramethyl‐2,2‐bis[4‐(4‐dicarboxyphenoxy)phenyl]propane dianhydride

A new bis(ether anhydride), 3,3′,5,5′‐tetramethyl‐2,2‐bis[4‐(4‐dicarboxyphenoxy)phenyl]propane dianhydride ( 3 ), was prepared in three steps: the nitro displacement of 4‐nitrophthalonitrile with 2,2‐bis(4‐hydroxy‐3,5‐dimethylphenyl)propane, the alkaline hydrolysis of the intermediate bis(ether dinitrile), and the subsequent dehydration of the resulting bis(ether diacid). A series of new highly soluble poly(ether imide)s with tetramethyl and isopropylidene groups were prepared from the bis(ether anhydride) 3 with various diamines by a conventional two‐stage synthesis including polyaddition and chemical cyclodehydration. The resulting poly(ether imide)s had inherent viscosities of 0.54–0.73 dL g^?1. Gel permeation chromatography measurements revealed that the polymers had number‐average and weight‐average molecular weights of up to 54,000 and 124,000, respectively. All the polymers showed typical amorphous diffraction patterns. All of the poly(ether imide)s showed excellent solubility and were readily dissolved in various solvents such as N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, N,N‐dimethylformamide, pyridine, cyclohexanone, tetrahydrofuran, and even chloroform. Most of the polymers could be dissolved with chloroform concentrations as high as 30 wt %. These polymers had glass‐transition temperatures of 244–282 °C. Thermogravimetric analysis showed that all polymers were stable, with 10% weight losses recorded above 463 °C in nitrogen. These transparent, tough, and flexible polymer films were obtained through solution casting from N,N‐dimethylacetamide solutions. These polymer films had tensile strengths of 81–102 MPa and tensile moduli of 1.8–2.0 GPa. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2556–2563, 2002     

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

A series of poly(amide–imide)s III_a–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 II_a–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 T_g 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     

Synthesis and properties of novel cardo aromatic poly(ether‐benzoxazole)s

Three new bis(ether‐acyl chloride) monomers, 1,1‐bis[4‐(4‐chloroformylphenoxy)phenyl]cyclohexane ( 1a ), 5,5‐bis[4‐(4‐chloroformylphenoxy)phenyl]‐4,7‐methanohexahydroindan ( 1b ), and 9,9‐bis[4‐(4‐chloroformylphenoxy)phenyl]fluorene ( 1c ), were synthesized from readily available compounds. Aromatic polybenzoxazoles bearing ether and cardo groups were obtained by the low‐temperature solution polycondensation of the bis(ether‐acyl chloride)s with three bis(aminophenol)s and the subsequent thermal cyclodehydration of the resultant poly(o‐hydroxy amide)s. The intermediate poly(o‐hydroxy amide)s exhibited inherent viscosities in the range of 0.35–0.71 dL/g. All of the poly(o‐hydroxy amide)s were amorphous and soluble in many organic polar solvents, and most of them could afford flexible and tough films by solvent casting. The poly(o‐hydroxy amide)s exhibited glass‐transition temperatures (T_g's) in the range of 141–169 °C and could be thermally converted into the corresponding polybenzoxazoles approximately in the region of 240–350 °C, as indicated by the DSC thermograms. Flexible and tough films of polybenzoxazoles could be obtained by thermal cyclodehydration of the poly(o‐hydroxy amide) films. All the polybenzoxazoles were amorphous and showed an enhanced T_g but a dramatically decreased solubility as compared with their poly(o‐hydroxy amide) precursors. They exhibited T_g's of 215–272 °C by DSC and showed insignificant weight loss before 500 °C in nitrogen or air. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 4014–4021, 2001     

Synthesis and properties of poly(ether imide)s based on a benzonorbornane bis(ether anhydride)

A novel bis(ether anhydride) monomer, 3,6‐bis(3,4‐dicarboxyphenoxy)benzonorbornane dianhydride, was synthesized from the nitro displacement of 4‐nitrophthalonitrile with 3,6‐dihydroxybenzonorbornane in the presence of potassium carbonate, followed by the alkaline hydrolysis of the intermediate bis(ether dinitrile) and the cyclodehydration of the resulting bis(ether diacid). A series of poly(ether imide)s bearing pendant norbornane groups were prepared from the bis(ether anhydride) with various aromatic diamines via a conventional two‐stage process that included ring‐opening polyaddition to form the poly(amic acid)s followed by thermal imidization to the poly(ether imide)s. The inherent viscosities of the poly(amic acid) precursors were 0.81–1.81 dL/g. The poly(ether imide) with m‐phenylenediamine as a diamine showed good organosolubility. Most of the cast poly(ether imide) films have had high tensile strengths and moduli. The glass‐transition temperatures of these poly(ether imide)s, except for those from rigid p‐phenylenediamine and benzidine, were recorded between 211 and 246 °C by differential scanning calorimetry. The softening temperatures of all the poly(ether imide) films stayed within 210–330 °C according to thermomechanical analysis. No polymers showed significant decomposition before 500 °C in a nitrogen or air atmosphere. A comparative study of the properties with the corresponding poly(ether imide)s without pendant substituents was also made. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1712–1725, 2002     

Synthesis and characterization of soluble polyimides derived from 2′,5′‐bis(3,4‐dicarboxyphenoxy)‐p‐terphenyl dianhydride

A novel bis(ether anhydride) monomer, 2′,5′‐bis(3,4‐dicarboxyphenoxy)‐p‐terphenyl dianhydride, was synthesized from the nitro displacement of 4‐nitrophthalonitrile by the phenoxide ion of 2′,5′‐dihydroxy‐p‐terphenyl, followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and cyclodehydration of the resulting bis(ether diacid). A series of new poly(ether imide)s bearing laterally attached p‐terphenyl groups were prepared from the bis(ether anhydride) with various aromatic diamines via a conventional two‐stage process that included ring‐opening polyaddition to form the poly(amic acid)s followed by thermal or chemical imidization to the poly(ether imide)s. The inherent viscosities of the poly(amic acid) precursors were in the range of 0.62–1.26 dL/g. Most of the poly(ether imide)s obtained from both routes were soluble in polar organic solvents, such as N,N‐dimethylacetamide. All the poly(ether imide)s could afford transparent, flexible, and strong films with high tensile strengths. The glass‐transition temperatures of these poly(ether imide)s were recorded as between 214 and 276 °C by DSC. The softening temperatures of all the poly(ether imide) films stayed in the 207–265 °C range according to thermomechanical analysis. For all the polymers significant decomposition did not occur below 500 °C in nitrogen or air atmosphere. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 1008–1017, 2004     

Novel ortho‐linked fluorinated poly(ether‐imide)s based on 2,2′‐substituted 1,1′‐binaphthyl units

In this research, a new fluorinated diamine based on 2,2′‐substituted 1,1′‐binaphthyl units, 2,2′‐bis(2‐amino‐4‐trifluoromethylphenoxy)‐1,1′‐binaphthyl (AFPBN) was synthesized and then used to prepare the corresponding ortho‐linked poly(ether‐imide)s via chemical polyimidization with several aromatic carboxylic dianhydrides. The resulting poly(ether‐imide)s were fully characterized by FT‐IR, NMR, viscosity measurements, gel‐permeation chromatography, UV–vis, X‐ray diffraction, organo‐solubility, thermogravimetric analysis (TGA), and differential scanning calorimetry. Probing optical behavior of the colorless films prepared from these poly(ether‐imide)s demonstrated that they possess a high degree of optical transparency, and UV–visible absorption cut‐off wavelength values were found to be in the range of 404–471 nm. The resulting polymers exhibited excellent organo‐solubility in polar solvents such as dimethylformamide, dimethyl sulfoxide, pyridine, and even tetrahydrofuran. To investigate the heat stability of the samples, their thermograms obtained from TGA were plotted, and for example, it is found that the 10% weight loss temperature of representative polymer AFPBN/3,3′,4,4′‐benzophenonetetracarboxylic dianhydride occurred at 532°C in nitrogen. These poly(ether‐imide)s had glass‐transition temperatures (T_g's) up to 280°C. Two previously prepared analogues of AFPBN, i.e. nonfluorinated diamine DAM1 and para‐linked fluorinated diamine DAM2 used to prepare the corresponding poly(ether‐imide)s, were also considered to compare the results obtained. Copyright © 2012 John Wiley & Sons, Ltd.     

Synthesis and properties of novel poly(aryl ether ketone)s containing both 2,6‐naphthylene moieties and amide linkages in the main chains

A new monomer, 2,6‐bis(4‐phenoxybenzoyl)naphthalene (BPOBON), was easily synthesized via simple synthetic procedures from readily available materials. A series of novel poly(aryl ether ketone)s containing both 2,6‐naphthylene moieties and amide linkages in the main chains were prepared by the Friedel‐Crafts acylation solution copolycondensation of isophthaloyl chloride with a mixture of BPOBON and N,N'‐bis(4‐phenoxybenzoyl)‐1,4‐phenylenediamine (BPBPPD), over a wide range of BPOBON/BPBPPD molar ratios, in the presence of anhydrous AlCl₃ and N‐methylpyrrolidone in 1,2‐dichloroethane. All the polymers are semicrystalline and had remarkably increased T_gs over the conventional PEEK and PEKK due to the incorporation of naphthalene and amide linkages in the main chains. The polymers with 50–70 mol% BPOBON had not only high T_gs of 179–186 °C, but also moderate T_ms of 321–328 °C, which are very suitable for the melt processing. These polymers had tensile strengths of 101.5–107.1 MPa, Young's moduli of 2.13–2.39 GPa, and elongations at break of 11.8–13.7% and exhibited excellent thermal stability and good resistance to organic solvents. Copyright © 2013 John Wiley & Sons, Ltd.