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Four starburst molecules with a triphenylamine (TPA) core through the amide group linked to the terminal triphenylamine or (N-phenyl)carbazole (NPC) unit, coded as T-3(NHCO-TPA), T-3(NHCO-NPC), T-3(CONH-TPA), and T-3(CONH-NPC), were synthesized and their electrochemistry and electropolymerization were investigated. The oxidation potential and the stability of the oxidized forms of the starbursts are affected by the orientation of amide linkage and the structure of terminal triarylamine unit. Robust polymeric films could be built onto ITO/glass surface by repetitive cyclic voltammetry (CV) of the T-3(NHCO-TPA) solution containing an electrolyte. The electrodeposited films exhibited reversible electrochemical processes and strong color changes upon electro-oxidation, which can be switched by potential modulation. The electrochromic behavior of the film was clearly interpreted on the basis of spectroelectrochemical studies. T-3(CONH-TPA) did not undergo electropolymerization effectively. T-3(CONH-NPC) also could electrochemically polymerize to polymer films upon repeated CV scans. However, their electrochromic switching stability is less than that of the polymer film from T-3(NHCO-TPA).

Two N-phenylcarbazole and triphenylamine end-capped, 2,7-bis(diphenylamino)naphthalene-cored dicarboxamides were prepared by the condensation reactions from N,N′-bis(4-aminophenyl)-N,N′-bis(4-methoxyphenyl)-2,7-naphthalenediamine with two equivalent amount of N-(4-carboxyphenyl)carbazole and 4-carboxytriphenylamine, respectively. These two dicarboxamides can be electropolymerized into electroactive films on the electrode surface in an electrolyte solution via the oxidative coupling reactions between the terminal arylamino groups. The electro-generated polymer films exhibited reversible electrochemical oxidation processes and strong color changes upon electro-oxidation, which can be switched by potential modulation. The electrochromic films did not delaminate from the electrode surface upon cycling electrochemically between their neutral and oxidized states.

Two novel electropolymerizable monomers, namely 3,5-bis(4-diphenylaminobenzamido)-N-[4-(carbazol-9-yl)phenyl]benzamide (5) and 3,5-bis(4-diphenylaminobenzamido)-N-[4-(3,6-dimethoxycarbazol-9-yl)phenyl]benzamide (5-MeO), were synthesized, and their electrochemical properties were studied by cyclic voltammetry. The electron-withdrawing amide groups efficiently blocked the radical cations delocalization between the two terminal TPA groups, rendering the electropolymerization of the TPA groups feasible. The polymer electrodeposited from monomer 5 could be further crosslinked through electro-coupling of the carbazole groups, which showed both electrochromic and fluorescent properties (the emission of blue light (460 nm) in solid state). Both of the electro-generated polymer films derived from 5 and 5-MeO showed reversible electrochemical oxidation processes in the range of 0 − 1.4 V with strong color changes and high contrast ratios in the visible and NIR regions upon electro-oxidation. © 2016 The Authors. Journal of Polymer Science Part A: Polymer Chemistry Published by Wiley Periodicals, Inc. 2016, 54, 2476–2485

In order to gain deeper insight into the linkage effect and donor–acceptor effect on memory behavior (from DRAM to WORM), 4-(N-carbazolyl)triphenylamine-based polyimides and polyamides t-butyl-6FPI, t-butyl-DSPI, OMe-6FPI, OMe-DSPI, t-butyl-6FPA, t-butyl-DSPA, OMe-6FPA, and OMe-DSPA were synthesized and their memory behaviours were investigated.

A carbazolyl-substituted triphenylamine derivative, 4-(N-carbazolyl)triphenylamine (TPACz), was synthesized and used to build a fluorescent and electrochromic polymeric film (PTPACz) on the ITO-glass surface by electrochemical oxidative coupling reactions. The electrodeposited PTPACz film showed blue emission (λmax = 424 nm) and exhibited reversible electrochemical redox processes and stable color changes upon electro-oxidation, which can be switched by potential modulation. The remarkable electrochromic behavior of the film is clearly interpreted on the basis of spectroelectrochemical studies. A dimethoxy-substituted derivative of TPACz, namely 4,4′-dimethoxy-4′′-(N-carbazolyl)triphenylamine (MeOTPACz), was also synthesized and characterized for a comparative study. Repetitive cyclic voltammetry scanning of MeOTPACz in an electrolyte/acetonitrile solution resulted in an electroactive dimeric film of (MeOTPACz)2 on the electrode surface. Electrochromic devices using PTPACz or (MeOTPACz)2 as an active layer were also fabricated as preliminary investigations for electrochromic applications.

This work deals with the synthesis and characterization of a new m-phenylenediamine-type monomer with pendent 3,6-dimethoxycarbazole group, namely N-(4-(3,6-dimethoxycarbazol-9-yl)phenyl)-3,5-diaminobenzamide (2), and its derived aromatic polyamides and polyimides. New electroactive aromatic polyamides were synthesized from diamine 2 with four aromatic dicarboxylic acids via the phosphorylation polyamidation technique, and the polyimides were prepared from equimolar mixtures of 4,4′-oxydianiline and diamine 2 with four aromatic tetracarboxylic dianhydrides via a conventional two-step procedure. All the polyamides and the 6FDA-derived polyimide were readily soluble in many organic solvents and could afford strong and flexible films by solution casting. The polymers showed useful levels of thermal stability with glass-transition temperatures (Tgs) in the range of 237–313 °C and 10% weight-loss temperatures in excess of 450 °C. All the polyamides and polyimides showed reversible electrochemical oxidation, accompanied by strong color changes. By incorporation of electron-donating methoxy groups on the electrochemically active C-3 and C-6 sites of the carbazole unit, the polymers exhibit greatly enhanced electrochemical stability and electrochromic performance in comparison with the analogs without any substituents on the carbazole unit.

Two electropolymerizable monomers with a methoxytriphenylamine core linked via amide groups to two triphenylamine (TPA) or N-phenylcarbazole (NPC) terminal groups, namely 4,4′-bis(4-diphenylaminobenzamido)-4′′-methoxytriphenylamine (MeOTPA-(TPA)2) and 4,4′-bis(4-(carbazol-9-yl)benzamido)-4′′-methoxytriphenylamine (MeOTPA-(NPC)2), were synthesized and characterized by FTIR and 1H NMR spectroscopy, mass spectrometry, and cyclic voltammetry. The electrochemical polymerization reactions of these MeOTPA-cored monomers over indium tin oxide (ITO) electrode allow the generation of electroactive poly(amide-amine) films. The electro-generated polymer films exhibited reversible redox processes and multi-colored electrochromic behaviors upon electro-oxidation, together with moderate coloration efficiency and cycling stability. The optical density changes (ΔOD) were observed in the range of 0.18–0.68 at specific absorption maxima, with the calculated coloration efficiencies of 42–123 cm2/C. Single-layer electrochromic devices using the electrodeposited polymer films as active layers were fabricated for the preliminary investigation of their electrochromic applications.

We developed a new efficient procedure for the synthesis of a bistriphenylamine diamine monomer, N,N′-bis(4-aminophenyl)-N,N′-bis(4-methoxyphenyl)-1,4-phenylenediamine (3). A new dicarboxylic acid monomer bearing two built-in imide rings, namely N,N′-bis(trimellitimidophenyl)-N,N′-bis(4-methoxyphenyl)-1,4-phenylenediamine (4), was synthesized from the condensation of diamine 3 with two equivalent amounts of trimellitic anhydride. Several novel electroactive poly(amide-imide)s (PAIs) containing N,N′-di(4-methoxyphenyl)-N,N′-diphenyl-p-phenylenediamine [TPPA(OMe)2] units have been prepared by the phosphorylation polyamidation reactions from diamine 3 with four imide ring-preformed dicarboxylic acids or from diimide-diacid 4 with 4,4′-oxydianiline and diamine 3, respectively. All the PAIs were readily soluble in many organic solvents and could be solution-cast into tough and flexible polymer films. These PAIs exhibited glass-transition temperatures (Tgs) in the range 206–292 °C, and most of them did not show significant weight-loss before 450 °C. The PAI films revealed reversible electrochemical oxidation processes accompanied with strong color changes from the pale yellow neutral state to yellowish green and deep blue oxidized. Incorporating the TPPA(OMe)2 unit on the amide side of PAIs led to lower oxidation potentials and higher redox and electrochromic stability.

Four bis(amide-triarylamine) derivatives featuring a triptycene as an interior core and terminal electroactive triphenylamine (TPA) or N-phenylcarbazole (NPC) groups were prepared by the condensation reactions from 1,4-bis(4-aminophenoxy)triptycene with 4-carboxytriphenylamine and N-(4-carboxyphenyl)carbazole, respectively, and from 1,4-bis(4-carboxyphenoxy)triptycene with 4-aminotriphenylamine and N-(4-aminophenyl)carbazole, respectively. The electrochemistry and electropolymerization of these bis(amide-triarylamine) derivatives were investigated. The stability of the oxidized forms of the bis(amide-triarylamine)s is affected by the orientation of amide linkage and the structure of terminal triarylamine unit. Two of the bis(amide-triarylamine)s could be electropolymerized into robust films on the electrode surface in an electrolyte solution. The electrogenerated polymer films exhibited reversible electrochemical oxidation processes and strong color changes upon electro-oxidation, which can be switched by potential modulation. The electrochromic properties of the films were evaluated by the spectroelectrochemical and electrochromic switching studies. The TPA-based film showed better electrochromic performance than the NPC-based one.

A series of novel polyimides based on N,N-di(4-ami- nophenyl)-1-aminopyrene and aromatic or alicyclic tetracarbox- ylic dianhydrides were synthesized. The polymers exhibited good solubility in many polar organic solvents and could afford robust films via solution casting. The polyimides derived from aromatic dianhydrides exhibited high thermal stability and high glass-transition temperatures (333-364 � C). Cyclic vol- tammetry studies of the polymer films showed that these poly- imides are both p and n dopable and have multicolored electrochromic states. For the polyimides derived from alicyclic dianhydrides, they revealed a strong blue-light emission with high fluorescence quantum yields (UPL > 45%) and a marked solvatochromic behavior. V C 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 49: 2210-2221, 2011

A new structurally asymmetric diamine monomer containing flexible ether linkages and bulky trifluoromethyl substituents, namely 1,3-bis(4-amino-2-trifluoromethylphenoxy)naphthalene, was prepared from 1,3-dihydroxynaphthalene and 2-chloro-5-nitrobenzotrifluoride. New series of fluorinated polyimides were synthesized from the diamine with six commercially available aromatic tetracarboxylic dianhydrides using a conventional two-stage process with thermal or chemical imidization. The resulting polyimides were highly soluble in a variety of organic solvents and could afford transparent and tough films via solution casting. These polyimides exhibited moderately high glass-transition temperatures (by DSC) of 236–268 °C and softening temperatures (by thermomechanical analysis) of 231–250 °C, and they did not show significant decomposition before 500 °C under either nitrogen or air atmosphere. Also, they revealed low moisture absorptions (0.32–0.78%), low dielectric constants (2.81–3.24 at 10 kHz), and high optical transparency (ultraviolet–visible absorption cutoff wavelengths of 377–426 nm).

A dicarboxylic acid bearing two preformed imide rings, namely 4,4′-bis(trimellitimido)-4″-methoxytriphenylamine ( 3 ), was prepared by the condensation of 4,4′-diamino-4″-methoxytriphenylamine ( 2 ) and two molar equivalents of trimellitic anhydride (TMA). A new family of aromatic poly(amide–imide)s (PAIs) containing the electroactive triphenylamine (TPA) unit were prepared by the triphenyl phosphite activated polycondensation of the diimide-diacid 3 with various aromatic diamines. All the polymers were readily soluble in many organic solvents and could be solution-cast into tough and flexible polymer films. They displayed high glass-transition temperatures (269–313 °C) and good thermal stability, with 10% weight-loss temperatures in excess of 521 °C in nitrogen and char yields at 800 °C in nitrogen higher than 68%. Cyclic voltammograms of the PAI films cast onto an indium–tin oxide (ITO)-coated glass substrate exhibited one reversible oxidation redox couple at 0.91–0.93 V vs. Ag/AgCl in acetonitrile solution. The polymer films revealed a good electrochemical and electrochromic stability, with a color change from colorless neutral form to blue oxidized form at applied potentials ranging from 0.0 to 1.2 V. The PAIs containing the TPA unit in both imide and amide segments showed multicolor electrochromism: pale yellow in the neutral state, green in the semi-oxidized state, and deep blue in the fully oxidized state.

A new triphenylamine-containing aromatic diamine monomer, 4-[4-(1-adamantyl)phenoxy]-4′,4″-diaminotriphenylamine, was synthesized from cesium fluoride-mediated N,N-diarylation of 4-(1-adamantyl)-4′-aminodiphenyl ether with 4-fluoronitrobenzene and subsequent reduction of the resultant dinitro compound. Novel electroactive aromatic polyamides and polyimides with adamantylphenoxy-substituted triphenylamine moieties were prepared from the newly synthesized diamine monomer with aromatic dicarboxylic acids and tetracarboxylic dianhydrides, respectively. All the resulting polymers were amorphous and most of them were readily soluble in polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc) and could be solution-cast into transparent and strong films with good mechanical properties. These polymers exhibited glass-transition temperatures between 254 and 310 °C, and they were fairly stable up to a temperature above 450 °C for the polyamides and above 500 °C for the polyimides. These polymers exhibited strong UV–vis absorption maxima at 293–346 nm in solution, and the photoluminescence spectra of polyamides showed maximum bands around 408–452 nm in the blue region. Cyclic voltammograms of the polyamide and polyimide films on an indium–tin oxide (ITO)-coated glass substrate exhibited one pair of reversible redox couples at half-wave oxidation potentials (E1/2) around 0.83–0.86 V and 1.12–1.13 V, respectively, versus Ag/AgCl in an acetonitrile solution. All the polymer films revealed good electrochemical and electrochromic stability by repeatedly switching electrode voltages between 0.0 V and 1.1–1.4 V, with coloration change from the pale yellowish neutral state to the green or blue oxidized state.

A series of novel fluorinated polynaphthalimides (PNIs) (2a–g) were synthesized from 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA) and trifluoromethyl (CF3)-substituted aromatic bis(ether amine)s (1a–g) by high-temperature solution polycondensation in m-cresol using isoquinoline as catalyst. Almost all the PNIs were readily soluble in polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc) and could be solution-cast to transparent and tough films with high tensile strengths. The PNIs exhibited high thermal stability, with glass-transition temperatures of 262–383 °C, 10% weight loss temperatures above 528 °C in nitrogen or air, and char yields at 800 °C in nitrogen higher than 50%. In comparison with analogous PNIs without the –CF3 substituents, these fluorinated PNIs revealed an enhanced solubility and better film-forming capability.

A series of electroactive aromatic polyamides with 4-(dimethylamino)triphenylamine [(NMe2)TPA] units in the backbone were prepared from a newly synthesized diamine monomer, 4,4′-diamino-4′′-(dimethylamino)triphenylamine, and various aromatic dicarboxylic acids via the phophorylation polyamidation reaction. These polyamides are readily soluble in many organic solvents and can be solution-cast into tough and amorphous films. They had useful levels of thermal stability associated with relatively high glass-transition temperatures (277–298 °C), 10% weight loss temperatures in excess of 500 °C, and char yields at 800 °C in nitrogen higher than 67%. The polymer films showed reversible electrochemical oxidation accompanied by strong color changes with high coloration efficiency, high contrast ratio, and rapid switching time. The optical transmittance change (Δ%T) at 640 nm between the neutral state and the fully oxidized state is up to 88%, and the coloration efficiency is as high as ca. 261 cm2/C with high opti...

A new series of polyarylates containing carbazolyl-substituted triphenylamine units were synthesized by direct polycondensation of 4,4′-dicarboxy-4″-N-carbazolyltriphenylamine with various bisphenols. All polymers were highly soluble in various common organic solvents and could afford tough, transparent, and colorless films by solution casting. These amorphous and organo-soluble polyarylates showed no significant decomposition below 470 °C in both nitrogen and air atmospheres with glass transition temperatures (Tg) ranging from 234 to 287 °C. In THF solution, these polyarylates exhibited blue photoluminescence around 464–476 nm with quantum yield up to 28%. The photoluminescence exhibited solvent effect and was red-shifted in the polar solvent at room temperature.

A new naphthylamine-derived aromatic dicarboxylic acid, 1-[N,N-di(4-carboxyphenyl)amino]naphthalene (2), was successfully synthesized by the sodium hydride-mediated condensation of 1-aminonaphthalene with 4-fluorobenzonitrile, followed by the alkaline hydrolysis of the intermediate dicyano compound 1. Four poly(amine−hydrazide)s were prepared from the polycondensation reactions of the dicarboxylic acid 2 and 4,4‘-dicarboxytriphenylamine (2‘) with terephthalic dihydrazide (TPH) and isophthalic dihydrazide (IPH), respectively, via the Yamazaki phosphorylation reaction. The poly(amine−hydrazide)s were readily soluble in many common organic solvents and could be solution cast into transparent and flexible films with good mechanical properties. These hydrazide polymers had glass-transition temperatures (Tg) in the range of 182−230 °C and could be thermally cyclodehydrated into the corresponding oxadiazole polymers in the range of 300−400 °C. The resulting poly(amine−1,3,4-oxadiazole)s had useful levels of ther...

A series of novel fluorinated poly(ether imide)s (IV) having inherent viscosities of 0.70–1.08 dL/g were prepared from 1,1-bis[4-(3,4-dicarboxyphenoxy)phenyl]cyclohexane dianhydride (I) and various trifluoromethyl (CF3)-substituted aromatic bis(ether amine)s IIa–g by a standard two-step process with thermal and chemical imidization of poly(amic acid) precursors. These poly(ether imide)s showed excellent solubility in many organic solvents and could be solution-cast into transparent, flexible, and tough films. These films were essentially colorless, with an ultraviolet-visible absorption edge of 375–380 nm and a very low b∗ value (a yellowness index) of 5.5–7.3. They also showed good thermal stability with glass-transition temperatures of 207–269 °C, 10% weight loss temperatures in excess of 474 °C, and char yields at 800 °C in nitrogen more than 62%. In comparison with analogous V series poly(ether imide)s without the –CF3 substituents, the IV series polymers showed better solubility, lower color intensity, and lower dielectric constants.

A series of novel triphenylamine-containing aromatic poly(amine–amide–imide)s (PAAIs) were prepared by the phosphorylation polyamidation reactions from the diamine, N,N-bis(4-aminophenyl)-N,N-diphenyl-1,4-phenylenediamine, and various imide ring-preformed dicarboxylic acids. All the PAAIs were amorphous, had good solubility in many polar aprotic solvents, and exhibited excellent thin Wlm forming capability with good mechanical properties. They displayed relatively high glass-transition temperatures (220–306 °C) and good thermal stability, with 10% weight-loss temperatures in excess of 522 °C in air or nitrogen and char yields at 800 °C in nitrogen higher than 66%. The solutions of polymers in NMP exhibited strong UV–vis absorption bands with a maximum around 315 nm. The hole-transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the PAAIs prepared by casting polymer solution onto an indium–tin oxide (ITO)-coated glass substrate exhibited two reversible oxidation redox couples at 0.63 and 1.01 V vs. Ag/AgCl in acetonitrile solution. All the PAAIs revealed very stable electrochromic characteristics, changing color from original pale brownish to green, and then to blue at 0.67 and 1.08 V, respectively.

Two series of new aromatic poly(ester-imide)s were prepared from 1,5-bis(4-aminobenzoyloxy)naphthalene ( p - 1 ) and 1,5-bis(3-aminobenzoyloxy)naphthalene ( m - 1 ), respectively, with six commercially available aromatic tetracarboxylic dianhydrides via a conventional two-stage synthesis that included ring-opening polyaddition to give poly(amic acid)s followed by chemical imidization to polyimides. The intermediate poly(amic acid)s obtained in the first stage had inherent viscosities of 0.41–0.84 and 0.66–1.37 dl/g, respectively. All the para -series and most of the meta -series poly(ester-imide)s were semicrystalline and showed less solubility. Two of the meta -series poly(ester-imide)s derived from less rigid dianhydrides were amorphous and readily soluble in polar aprotic solvents, and they could be solution-cast into transparent and tough films with good mechanical properties. The meta -series polymers derived from rigid dianhydrides were generally semicrystalline and showed less solubility. Except for one example, the meta -series poly(ester-imide)s displayed discernible T g s in the range 239–273 °C by DSC. All of these two series poly(ester-imide)s did not show significant decomposition below 450 °C in nitrogen or in air.

A new dicarboxylic acid, 2,4-bis( N -trimellitoyl)triphenylamine, bearing two preformed imide rings was synthesized from the condensation of 2,4-diaminotriphenylamine and trimellitic anhydride at 1:2 molar ratio. A series of poly(amide-imide)s (PAIs) with inherent viscosities of 0.38–0.66 dl/g were prepared by triphenyl phosphite-activated polycondensation from the diimide–dicarboxylic acid with various aromatic diamines. All the resulting PAIs were readily soluble in a variety of organic solvents and formed strong and tough films via solution casting. These PAIs have useful levels of thermal stability associated with moderately high glass-transition temperatures (259–314 °C) and 10% weight loss temperatures in excess of 530 °C in nitrogen or in air.

A new naphthalene ring-containing bis(ester amine), 1,5-bis(4-aminobenzoyloxy)naphthalene ( 2 ), was synthesized from the condensation of 1,5-dihydroxynaphthalene with 4-nitrobenzoyl chloride followed by catalytic hydrogenation. A series of naphthalene-containing poly(ester amide)s having inherent viscosities of 0.34–0.82 dl/g were prepared by the direct phosphorylation polyamidation from bis(ester amine) 2 with various aromatic dicarboxylic acids. The poly(ester amide)s derived from terephthalic acid, 4,4′-biphenyldicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 4,4′-oxydibenzoic acid were semicrystalline and showed less solubility. The other polymers were amorphous and readily soluble in polar organic solvents and gave flexible and tough films via solution casting. Except for four examples, the poly(ester amide)s displayed discernible glass transitions between 190 and 227 °C by differential scanning calorimetry. These poly(ester amide)s did not show significant decomposition below 400 °C in nitrogen or air.

Two series of new polyamides containing flexible ether linkages and laterally attached side rods ( 3a-i and 4a-i ) were synthesized from 2 ′ ,5 ′ -bis(4-aminophenoxy)-[1,1 ′ ;4 ′ ,1 ″ ]terphenyl ( 1a ) and 2 ′ ,5 ′ -bis(4-amino-2-trifluoromethylphenoxy)-[1,1 ′ ;4 ′ ,1 ″ ]terphenyl ( 1b ), respectively, with various aromatic dicarboxylic acids by the direct phosphorylation polycondensation. The polymers were produced with high yields and moderate to high inherent viscosities (0.41–0.97 dl/g) that corresponded to weight-average molecular weights (by size exclusion chromatography) of 47,000–65,000. Except for some polyamides that derived from rigid diacids, the obtained polyamides were readily soluble in aprotic polar solvents, such as N -methyl-2-pyrrolidone (NMP) and N , N -dimethylacetamide (DMAc), and could afford flexible and tough films via solvent casting. The polymer films cast from DMAc solutions possessed tensile strengths of 85–106 MPa and initial moduli of 1.82–2.96 GPa. These polyamides showed glass-transition temperatures ( T g ) in the range of 206–263 °C (by DSC) and softening temperatures ( T s ) in the range of 211–253 °C (by TMA). Decomposition temperatures ( T d ) for 10% weight loss all occurred above 400 °C (by TGA) in both nitrogen and air atmospheres. The polyamides 4a-i derived from trifluoromethyl-substituted diamine 1b generally showed a higher solubility, T g and T s but lower thermal stability as compared to the analogous polyamides 3a-i based on diamine 1a .

A new series of fluorine-containing polyarylates were synthesized by interfacial or high-temperature solution polymerization of 1,1-bis(4-hydroxyphenyl)-1-phenyl-2,2,2-trifluoroethane with six aromatic diacyl chlorides. These polyarylates had inherent viscosities ranging from 0.47 to 1.37 dl/g that corresponded to weight-average and number-average molecular weights (by gel permeation chromatography) of 35,800–72,400 and 30,700–67,700, respectively. All polymers were highly soluble in a variety of solvents, and could afford tough, transparent, and colorless films via solution casting. The glass-transition temperatures of the polymers ranged from 209 to 271 °C. All of them did not show significant decomposition below 450 °C in both nitrogen and air atmospheres.

A new trifluoromethylated bis(ether amine), 1,5-bis(4-amino-2-trifluoromethylphenoxy)naphthalene, was synthesized in two steps starting from 1,5-dihydroxynaphthalene and 2-chloro-5-nitrobenzotrifluoride via nucleophilic aromatic substitution and catalytic reduction. A series of novel fluorinated polyimides with moderate to high molecular weights were synthesized from the diamine with various aromatic tetracarboxylic dianhydrides using a conventional two-stage process. All polyimides could afford flexible and tough films and most of them were soluble in strong polar solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). The polyimides showed glass-transition temperatures (Tg) in the range of 253–315 °C (by DSC) and softening temperatures (Ts) in the range of 250–300 °C (by TMA). Decomposition temperatures for 5% weight loss all occurred above 500 °C in both air and nitrogen atmospheres. The dielectric constants of these polymers ranged from 3.17 to 3.64 at 1 MHz. The properties of these fluorinated polyimides were also compared with those of polyimides prepared from 1,5-bis(4-aminophenoxy)naphthalene with the same dianhydrides.

A series of poly( o -hydroxy amide)s having both ether and ortho -catenated phenylene unit in the main chain were synthesized via the low-temperature solution polycondensation of 4,4 ′ -(1,2-phenylenedioxy)dibenzoyl chloride and 4,4 ′ -(4- tert -butyl-1,2-phenylenedioxy)dibenzoyl chloride with three bis( o -aminophenol)s including 4,4 ′ -diamino-3,3 ′ -dihydroxybiphenyl, 3,3 ′ -diamino-4,4 ′ -dihydroxybiphenyl, and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. The poly( o -hydroxy amide)s exhibited inherent viscosities in the range of 0.23–0.96 dl/g. Most of the poly( o -hydroxy amide)s were soluble in polar organic solvents such as N , N -dimethylacetamide (DMAc) and N -methyl-2-pyrrolidone (NMP) and could afford flexible and tough films by solution casting. Subsequent thermal cyclodehydration of the poly( o -hydroxy amide)s afforded polybenzoxazoles. However, the polybenzoxazoles were organic-insoluble except for those with the hexafluoroisopropylidene group. The polybenzoxazoles exhibited glass-transition temperatures ( T g ) in the range of 200–232 °C by DSC and softening temperatures ( T s ) of 250–256 °C by thermomechanical analysis. Thermogravimetric analyses indicated that most polybenzoxazoles were stable up to 500 °C in air or nitrogen. The 10% weight loss temperatures were recorded in the ranges of 546–606 °C in air and 574–631 °C in nitrogen.

Two series of novel fluorinated aromatic polyamides were prepared from 2,2′-bis(4-amino-2-trifluoromethylphenoxy)biphenyl (2) and 2,2′-bis(4-amino-2-trifluoromethylphenoxy)-1,1′-binaphthyl (4) with various aromatic dicarboxylic acids using the phosphorylation polycondensation technique. The polyamides had inherent viscosities ranging from 0.43 to 0.62 dl/g and 0.36 to 0.74 dl/g, respectively. All the fluorinated polyamides were soluble in many polar organic solvents such as N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone, and afforded transparent, light-colored, and flexible films upon casting from DMAc solvent. These polyamides showed glass-transition temperatures in the ranges of 190–240 °C (for the 6 series from diamine 2) and 247–255 °C (for the 7 series from diamine 4) by differential scanning calorimetry, softening temperatures in the ranges of 196–230 °C (6 series) and 241–291 °C (7 series) by thermomechanical analysis, and decomposition temperatures for 10% weight loss above 420 °C in both nitrogen and air atmospheres.

Polyhydrazides and poly(amide-hydrazide)s having inherent viscositie so f0 .31-1.17 dL g −1 were prepared from two ether-naphthalene-dicarboxylic acids, 4,4'-(1,5-naphthalene dioxy)dibenzoic acid (1,5-NDA) and 4,4'-(2,3-naphthalenedioxy)dibenzoic acid (2,3-NDA) with terephthalic dihydrazide, isophthalic dihydrazide, and p- aminobenzhydrazide via the phosphorylation polycondensation reaction. Except for one example, the hydrazide poly- mers were essentially amorphous and readily soluble in polar organic solvents such as N-methyl-2-pyrrolidone (NMP) and N,N-dimethylacetamide (DMAc). They could be cast into transparent, flexible, and tough films with good mechani- cal strengths from solution in DMAc. These hydrazide polymers exhibited glass-transition temperatures (Tgs) in the range 179-190 ◦ Ca nd could be thermally cyclodehydrated into the corresponding poly(1,3,4-oxadiazole)s and poly(amide- 1,3,4-oxadiazole)s in the solid state at elevated temperatures. The oxadiazole polymers had Tg so f228-242 ◦ C( by differential scanning calorimetry) and 10% weight loss temperatures above 500 ◦ C, as revealed by thermogravimetric

A series of aromatic diamines were polymerized with two aromatic dianhydrides, pyromellitic dianhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride, and the resulting poly(amic acid)s were thermally cyclodehydrated to aromatic polyimides. The polyimides were characterized by determining the glass transition temperatures (Tg), thermal stability, coefficients of thermal expansion, and wide-angle X-ray diffraction. Structure–property relationships are elucidated and discussed in terms of the structural fragments in the polymer chain. The PMDA-based polyimides generally revealed a higher Tg than the corresponding BPDA-based analogues. Generally, the dilution of the imide content by the insertion of oxyphenylene segments into the diamines significantly reduced the Tg. The introduction of m- or o-phenylene units into the polymer backbone usually resulted in a decrease in Tg. The attachment of pendant groups on the backbone may lead to decreased or increased Tgs, depending on the structure of pendant groups. As evidenced by X-ray diffraction, the polyimides derived from rigid, rod-like diamines or the diamines having two or three p-oxyphenylene showed a higher crystalline tendency. The presence of aliphatic pendant groups slightly reduced the thermal stability of the polyimides. The other structural changes did not show a dramatic influence on the thermal stability. Some polyimides obtained from p- or m-phenylenediamine had low thermal expansion coefficients below 2×10 −5 ° C−1.

A set of new aromatic polyamides containing ether and benzonorbornane units were synthesized by the direct phosphorylation polycondensation of 3,6-bis(4-aminophenoxy)benzonorbornane (BAPBN) with various aromatic dicarboxylic acids. The polymers were produced with high yields and medium inherent viscosities (0.40–0.82 dL g-1). The polyamides based on rigid diacids showed limited solubility in organic solvents and could not afford ductile films. The polyamides derived from less rigid diacids were readily soluble in polar organic solvents and gave flexible and tough films via solvent casting. These polyamides showed glass-transition temperatures in the range of 200–269°C (by DSC), softening temperatures in the range of 220–289°C (by TMA), and 10% weight loss temperatures in excess of 450°C (by TGA). For a comparative study, a series of analogous polyamides based on 1,4-bis(4-aminophenoxy)benzene (BAPB) were also prepared and characterized.

A series of polyarylates containing sulfone or both of ether and sulfone groups were synthesized from diacid chlorides such as 4,4′-sulfonyldibenzoyl chloride (SDBC), 4,4′-[sulfonylbis(1,4-phenylene)dioxy]dibenzoyl chloride (SODBC), and 4,4′-[sulfonylbis(2,6-dimethyl-1,4-phenylene)dioxy]dibenzoyl chloride (4MeSODBC) with various bisphenols by the interfacial polycondensation technique. Moderate to high molecular weight polyarylates with inherent viscosity up to 1.22 dL g−1 were obtained. Most of them were soluble in various organic solvents and afforded transparent, flexible, and tough films by solution casting. Two polyarylates based on SDBC exhibited a moderate level of crystallinity and poor solubility; however, the introduction of ether linkages into the polymer backbone caused a decreased crystallinity and an enhanced solubility. The incorporation of ether groups in the sulfonyl polyarylate main chain led to a decreased glass transition temperature (Tg) or softening temperature (Ts). The methyl-substituted poly(ether-sulfonearylate)s from 4MeSODBC reveal higher Tg or Ts but lower decomposition temperatures than the corresponding nonsubstituted analogs from SODBC.

Thermoplastic and organic-soluble aromatic polyamides containing both bulky triphenylethane units and flexible ether linkages were prepared directly from 1,1-bis[4-(4-carboxyphenoxy)phenyl]-1-phenylethane (III) with various aromatic diamines or from 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane (V) with various aromatic dicarboxylic diacids via triphenyl phosphite and pyridine. These polyamides had inherent viscosities ranging from 0.71 to 1.77 dL/g. All the polymers easily were dissolved in aprotic polar solvents such as N-methyl-2-pyrrolidone and N,N-dimethylacetamide, and some even could be dissolved in less polar solvents such as tetrahydrofuran. The flexible and tough films cast from the polymer solutions possessed tensile strengths of 89 to 104 MPa. The polyamides were thermally stable up to 460°C in air or nitrogen. Glass-transition temperatures of these polyamides were observed in a range of 179 to 268°C via differential scanning calorimetry or thermomechanical analysis.

An ether diamine monomer containing the cyclohexane structure, 1,1-bis[4-(4-aminophenoxy)phenyl]cyclohexane (BAPC), was prepared through nucleophilic substitution reaction of 1,1-bis(4-hydroxyphenyl)cyclohexane and p-chloronitrobenzene in the presence of K2CO3, followed by catalytic hydrazine reduction. Using triphenyl phosphite and pyridine as condensing agent, novel polyamides were directly polycondensated from BAPC with various aromatic dicarboxylic acids in the N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. The resulting polyamides had inherent viscosities from 0.97 to 1.61 dLg−1. Most had good solubility in polar organic solvents such as NMP and N,N-dimethylacetamide, and afforded transparent, flexible, and tough films by solution casting. The glass transition temperatures (Tg) of the polymers were 188—240°C and 10% mass loss temperatures were recorded at 473—499°C in air. A comparative study on the properties with corresponding polyamides derived from 1,1-bis[4-(4-carboxyphenoxy)phenyl]cyclohexane (BCPC) was made.

A diimide dicarboxylic acid, 1,4-bis(4-trimellitimidophenoxy)-2-t-butylbenzene (I), was prepared by the condensation of 1,4-bis(4-aminophenoxy)-2-t-butylbenzene (BAP-tBB) and trimellitic anhydride (TMA) in 1:2 molar ratio. A series of novel poly(amide-imide)s (PAIs) IIIa−1 having inherent viscosities of 0.98–1.51 dL g−1 were prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid I with various aromatic diamines (IIa−1) in a medium consisting of N-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of polymers show excellent solubility in amide-type solvents such as NMP and N,N-dimethylacetamide (DMAc) and formed tough, transparent, and flexible films by casting from DMAc solution. These films had tensile strengths of 71–106 MPa, elongations at break of 5–45%, and initial moduli of 2.1–2.9 GPa. Most PAIs necked during the tensile testing. The glass transition temperatures of these polymers were in the range 228–286°C and the 10% weight loss temperatures were above 475°C in air or in nitrogen.

Two bis(ether anhydride) monomers, 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propane dianhydride (4) and 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]hexafluoropropane dianhydride (4-F), were synthesized from readily available compounds in three steps in high yields. Two series of poly(ether imide)s 7a-g and 7a-g-F based on dianhydrides 4 and 4-F, respectively, were synthesized by a conventional two-step procedure that included a ring-opening polyaddition to give poly(amic acid)s, followed by cyclodehydration to polyimides. The intermediate poly(ether amic acid)s and the poly(ether imide)s had inherent viscosities in the range of 0.29–1.09 dL g−1 and 0.21–0.98 dL g−1, respectively. Except for the poly(ether imide)s derived from benzidine, the others afforded flexible and tough films. Most of the obtained poly(ether imide)s are organic-soluble. The glass transition temperatures (Tg) of these polymers ranged from 204 to 259°C. Degradation temperatures for 10% weight loss all occurred above 505°C in nitrogen and above 501°C in air. Fluorine-containing poly(ether imide)s showed higher solubility, Tgs and degradation temperatures in nitrogen, as compared to their respective nonfluorine-containing counterparts.

A series of novel fluorinated poly(ether imide)s (PEIs) IVa-h were synthesized from 4,4’-(2,5-tolylenedioxy)diphthalic anhydride (I) and various trifluoromethyl-substituted aromatic bis(ether amine)s (IIa-h) via a conventional two-step method with thermal or chemical imidization of the precursor poly(amic acid)s. These PEIs were readily soluble in a variety of organic solvents; they were soluble with a concentration higher than 10% in amide-type polar solvents, ether type solvents, and chlorinated hydrocarbons. The solution-cast films showed a high optical transparency and low color intensity, with an ultraviolet-visible absorption edge of 371- 377 nm and low b* values (a yellowness index) of 4.9-7.5. These films were strong and tough with tensile strength of 90-103 MPa. They exhibited glass-transition temperatures (Tg) in the range of 207-293oC, with 10% weight loss temperature in excess of 500oC in air or nitrogen atmosphere. They also showed low-dielectric constants (2.95-3.37 at 1 MHz) and low moisture absorption (0.20- 0.67 wt %).