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Two electropolymerizable monomers with a methoxytriphenylamine core linked via amide groups to two triphenylamine (TPA) or N-phenylcarbazole (NPC) terminal groups, namely 4,40-bis(4-diphenylaminobenzamido)-40 0-methoxytriphenylamine (MeOTPA-(TPA)2) and 4,40-bis(4-(carbazol-9-yl)benzamido)-40 0-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 (DOD) 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. [ABSTRACT FROM AUTHOR]

Two series of polyamides and polyimides containing bulky trityl-substituted triphenylamine units were synthesized from condensation reactions of 4,40-diamino-400-trityltriphenylamine with various dicarboxylic acids and tetracarboxylic dianhydrides, respectively. The polymers showed good solubility and film-forming ability. Flexible or robust films could be readily obtained via solution-casting. The use of aliphatic diacid or dianhydride reduces interchain charge transfer complexing and leads to colorless polyamide and polyimide films. These polymers showed glass-transition temperatures in the range of 206-336 #176;C. Cyclic voltammograms of the polyamide and polyimide films displayed reversible electrochemical oxidation processes in the range of 0-1.0 or 0-1.3 V. Upon oxidation, the color of polymer films changes from colorless to blue-green or blue. As compared to the polyimide counterparts, the polyamides showed lower oxidation potentials and thus a higher electrochromic stability and coloration efficiency. Simple electrochromic devices were also fabricated as a preliminary investigation for electrochromic applications of the prepared polymers. [ABSTRACT FROM AUTHOR]

Two bisimide compounds, TPA--TPDI and NPC--TPDI, consisting of a triptycene core and two triphenylamine (TPA) or N-phenylcarbazole (NPC) end groups were successfully synthesized by the condensation reactions from 1,4-bis(3,4-dicarboxyphenoxy)triptycene dianhydride with 4-aminotriphenylamine and N-(4-aminophenyl)carbazole, respectively. These two monomers could polymerize electrochemically via the oxidative coupling reactions of triarylamine units. The electrochemical and spectroelectrochemical properties of the electro-generated triptycene poly(ether-imide)s (TPA--TPPI and NPC--TPPI) were studied. Both polymers have two colored oxidation states, and TPA--TPPI showed better electrochromic performance than NPC--TPPI. [ABSTRACT FROM AUTHOR]

Two new pyrenylamine-based polyimides were prepared from the polycondensation reaction of N,N-di(4-aminophenyl)-1-aminopyrene with pyromellitic dianhydride (PMDA) or 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTDA). The polyimide derived from PMDA is soluble in hot N-methyl-2-pyrrolidone and can be solution-cast into a flexible and strong film. The polyimides showed high glass transition temperatures (Tg> 364 °C) and high thermal stability. Cyclic voltammetry studies revealed that these two polyimides were ambipolar; they showed well-defined and reversible redox couples during both p- and n-doping processes, together with multi-electrochromic behaviors. The polymer films also exhibited high coloration efficiency, high redox stability, and fast response time. [ABSTRACT FROM AUTHOR]

series of colorless and organosoluble poly(ether-imide)s (PEIs) were prepared from a phenylhydroquinone bis(ether anhydride), i.e., 2,5-bis(3,4-dicarboxyphenoxy)biphenyl dianhydride, and seven trifluoromethyl-containing bis(ether amine)s by the conventional two-stage process via the thermal or chemical imidization of the precursor poly(amic acid)s. The fluorinated PEIs prepared via the chemical imidization procedure had inherent viscosities of 0.46-1.27 dL/g and weight-average molecular weights of 68,000-87,500. The PEIs exhibited good solubility in a variety of organic solvents; they were readily soluble in amide-type polar solvents and chlorinated hydrocarbons on a concentration higher than 10%. The solution-cast films showed a high optical transparency and low color intensity, with an ultraviolet-visible absorption edge of 368-375 nm and a yellowness index of 5.9-9.9. These films were flexible and tough with tensile strengths of 89-114 MPa. They exhibited glass-tranisition temperatures of 198-250°C and 10% weight loss temperatures higher than 488°C in air or nitrogen. In addition, these PEI films also displayed low dielectric constants (3.22-3.52 at 1 MHz) and low moisture absorptions (0.22-0.73 wt%). [ABSTRACT FROM AUTHOR]

A series of novel polyamides with a pyrenylamine chromophore in the backbone were prepared from a newly synthesized diamine monomer, N,N-di(4-aminophenyl)-1-aminopyrene, and various dicarboxylic acids viathe phosphorylation polyamidation technique. These polyamides were readily soluble in many organic solvents and could be solution-cast into tough and amorphous films. They had useful levels of thermal stability with glass-transition temperatures in the range of 246–326 °C and 10% weight loss temperatures in excess of 500 °C. The dilute NMP solutions of these polyamides exhibited fluorescence maxima around 522–544 nm with quantum yields up to 30.2%. These polyamides also showed remarkable fluorescence solvatochromism in various solvents. The polymer films showed reversible electrochemical oxidation and reduction accompanied by strong color changes from the yellow neutral state to a purple oxidized state and to an orange reduced state. The anodically electrochromic films had high coloration efficiency (up to 172 cm2C−1at 834 nm) and good redox stability, which still retained a high electroactivity after long-term redox cycles. [ABSTRACT FROM AUTHOR]

The thermal degradation behaviours of a novel aromatic poly(ester–imide) (PEI) derived from pyromellitic dianhydride and 2,7-bis(4-aminobenzoyloxy)naphthalene have been investigated by thermogravimetric analysis (TGA) and by pyrolysis–gas chromatography/mass spectrometry (pyrolysis–GC/MS). The weight of PEI fell slightly in the temperature range of 350–450 °C in the TGA analysis, but the major weight loss occurred at 520 °C. Evolve gas analysis (EGA) of the PEI showed maximum release of pyrolyzates at 550 °C. The chemical structure of the volatile products resulted from the PEI pyrolysis at different temperatures was identified by pyrolysis–GC/MS. The cleavage of the ester linkage within the polymer chain initiated at 350 °C, and bond scission in the partially hydrolyzed pyromellitimide unit occurred in the temperature range of 450–500 °C. The bonds within the pyromellitimide unit started to cleave at 550 °C. The extensive decomposition of the pyromellitimide segment within the polymer backbone occurred at 600 °C. The possible thermal degradation pathways of this PEI are proposed on the basis of the pyrolysis products. [ABSTRACT FROM AUTHOR]

Two new naphthalene-ring-containing bis(ester-amine)s, 2,3-bis(4-aminobenzoyloxy)naphthalene ( p- 2) and 2,3-bis(3-aminobenzoyloxy)naphthalene ( m- 2), were prepared from the condensation of 2,3-dihydroxynaphthalene with 4-nitrobenzoyl chloride and 3-nitrobenzoyl chloride, respectively, followed by catalytic hydrogenation. The novel aromatic poly(ester-amide)s and poly(ester-imide)s having 2,3-linked bis(benzoyloxy)naphthalene units have been synthesized from the polycondensation reactions of bis(ester-amine)s ( p- 2 and m- 2) or an equimolar mixture of 4,4′-oxydianiline and p- 2 or m- 2 with various aromatic dicarboxylic acids and dianhydrides. The synthesis of the poly(ester-amide)s was achieved by the phosphorylation polyamidation reaction by means of triphenyl phosphate, and the synthesis of the poly(ester-imide)s included ring-opening polyaddition to give poly(amic acid)s followed by chemical imidization to polyimides. Most of the poly(ester-amide)s were readily soluble in various organic solvents. Six poly(ester-amide)s and two poly(ester-imide)s derived from less rigid diacids and dianhydrides, respectively, were amorphous and could be solution-cast into transparent and tough films with good mechanical properties. Most of the poly(ester-amide)s displayed discernible glass-transition temperatures ( T gs) between 192 and 223 °C in the DSC traces. All of the poly(ester-imide)s, except for one sample, showed clear T g values between 225 and 265 °C by DSC. These poly(ester-imide)s showed excellent thermal stability with 10 wt% loss temperatures above 460 °C in nitrogen or air. [ABSTRACT FROM AUTHOR]

A series of polyimide precursors, poly(amic acid)s, containing propyltrimethoxysliane at two chain ends were prepared from 4,4′‐bis(4‐amino‐2‐trifluoromethylphenoxy)biphenyl (I) with six commercially available dianhydrides, followed by end‐capping with 3‐aminopropyltrimethoxysilane (APrTMOS). A new class of fluorine‐containing polyimide/silica composite films (III) with chemical bonds between the fluorinated polyimide backbone and the silica network has been synthesized from the APrTMOS‐terminated precursors with tetramethoxysilane via the sol‐gel process and thermal cyclodehydration. The resultant hybrid films were light‐colored, flexible, and tough. They had high levels of thermal stability associated with high glass‐transition temperatures (>251°C), 10% weight‐loss temperatures in excess of 527°C, and char yields at 800°C in nitrogen higher than 60%. For a comparative study, the analogous nonfluorinated polyimide/silica hybrid films (III′), based on 4,4′‐bis(4‐aminophenoxy)biphenyl (I′), and the neat fluorinated polyimide films (IV), based on diamine I, were also synthesized and characterized. The hybrid films of the fluorinated series III showed a higher transparency and less color intensity when compared with the nonfluorinated III′ analogs. They also revealed a lower refraction index and birefringence than pure polyimides (IV). © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4046–4052, 2007 [ABSTRACT FROM AUTHOR]

Two series of new blue photoluminescent aromatic polyesters (polyarylates) were synthesized from 4,4′-dicarboxytriphenylamine and 4,4′-dicarboxy-4″-methyltriphenylamine with various bisphenols by the diphenylchlorophosphate (DPCP) activated direct polycondensation in a medium of pyridine and lithium chloride. These polymers were amorphous and readily soluble in various common organic solvents including DMAc, THF, and chloroform, and could be cast from their chloroform solutions into transparent films due to their excellent solubility. These polyarylates exhibited moderately high T g values (186–264 °C) and thermal stability. In THF solution, these triphenylamine-containing polyarylates showed UV-Vis absorption bands at 359–365 nm and photoluminescence peaks around 427–451 nm in the blue region. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A series of novel aromatic polyarylates with triphenylamine units in the main chain and as the pendent group were prepared from the dicarboxylic acid monomer, N,N‐bis(4‐carboxyphenyl)‐N′, N′‐diphenyl‐1,4‐phenylenediamine (1), and various bisphenols. These polyarylates were amorphous and readily soluble in common organic solvents. They had excellent levels of thermal stability associated with moderately high Tg values (182–263 °C). These polymers exhibited strong UV–vis absorption bands at 357–360 nm in toluene solution and the photoluminescence spectra showed maximum bands around 493–503 nm in the green region. The hole‐transporting and electrochromic properties were examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the polyarylates exhibited two reversible oxidation redox couples in acetonitrile solution at Eonset 0.77–0.79 V and 1.12–1.14 V, respectively. The typical polymer 3b film revealed good stability of electrochromic characteristics, with color change from colorless to green and blue at applied potentials ranging from 0.00 to 1.24 V. These anodically polymeric electrochromic materials not only showed excellent reversible electrochromic stability with good green coloration efficiency (CE = 159 cm2/C) and blue coloration efficiency (CE = 154 cm2/C) but also exhibited high contrast of optical transmittance change (ΔT%), 54% in 895 nm for green color and up to 84% in 595 nm for blue color. After over 100 cyclic switches, the polymer films still exhibited excellent stability of electrochromic characteristics. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2004–2014, 2007 [ABSTRACT FROM AUTHOR]

A series of organic‐soluble polynaphthalimides (PNI) bearing flexible ether links and phthalide cardo group were synthesized from 1,4,5,8‐naphthalenetetracarboxylic dianhydride (NTDA) with 3,3‐bis[4‐(4‐aminophenoxy)‐3‐methylphenyl]phthalide (BAMP) and its equimolar mixtures with other dietheramines by high‐temperature solution polycondensation in m‐cresol. The PNIs had moderate to high inherent viscosities in the range of 1.24–2.25 dL/g and could afford flexible and tough films with tensile strengths of 97–138 MPa by casting their m‐cresol solutions. These PNIs exhibited high thermal stability, with glass transition temperature of 291°C–321°C, 10% weight‐loss temperatures above 542°C, and char yields at 800°C in nitrogen higher than 56%. In comparison with PNIs without the BAMP component, these BAMP‐modified PNIs revealed an enhanced solubility and film‐forming capability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1104–1109, 2007 [ABSTRACT FROM AUTHOR]

A series of novel organosoluble and light‐colored fluorinated poly(ether imide)s (PEIs) (IV) having inherent viscosities of 0.43–0.59 dL/g were prepared from 4,4′‐[1,4‐phenylenbis(isopropylidene‐1,4‐phenyleneoxy)]diphthalic anhydride (I) and various trifluoromethyl‐substituted aromatic bis(ether amine)s by a standard two‐step process with thermal and chemical imidization of poly(amic acid) precursors. These PEIs showed excellent solubility in many organic solvents and could be solution‐cast into transparent and tough films. These films were essentially colorless, with an UV–visible absorption edge of 361–375 nm and a very low b* value (a yellowness index) of 15.3–17.0. They also showed good thermal stability with glass‐transition temperature of 191–248°C, 10% weight loss temperature in excess of 494°C, and char yields at 800°C in nitrogen more than 39%. The thermally cured PEI films showed good mechanical properties with tensile strengths of 83–96 MPa, elongations at break of 8–11%, and initial moduli of 1.7–2.0 GPa. They possessed lower dielectric constants of 3.25–3.72 (1 MHz). In comparison with the V series nonfluorinated PEIs, the IV series showed better solubility, lower color intensity, and lower dielectric constants. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 620–628, 2007 [ABSTRACT FROM AUTHOR]

A 4-methoxy-substituted triphenylamine containing the aromatic diamine, 4,4′-diamino-4″-methoxytriphenylamine (2), was synthesized by the caesium fluoride-mediated condensation of p-anisidine with 4-fluoronitrobenzene, followed by palladium-catalyzed hydrazine reduction of the dinitro intermediate. A series of new polyamides with pendent 4-methoxy-substituted triphenylamine (TPA) units having inherent viscosities of 0.27–1.39 dL g−1 were prepared via the direct phosphorylation polycondensation of various dicarboxylic acids and the diamine (2). All the polymers were readily soluble in many organic solvents, such as N-methyl-2-pyrrolidinone (NMP) and N,N-dimethylacetamide (DMAc), and could be solution-cast into tough and flexible polymer films. These aromatic polyamides had useful levels of thermal stability associated with their relatively high softening temperature (242–282 °C), 10% weight-loss temperatures in excess of 470 °C, and char yields at 800 °C in nitrogen higher than 60%. The hole-transporting and electrochromic properties are examined by electrochemical and spectroelectrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium-tin oxide (ITO)-coated glass substrate exhibited reversible oxidation at 0.73–0.79 V versus Ag/AgCl in acetonitrile solution, and revealed excellent stability of electrochromic characteristics with a color change from colorless to green at applied potentials ranging from 0.00 to 1.05 V. These anodically polymeric electrochromic materials not only showed excellent reversible electrochromic stability with good green coloration efficiency (CE = 374 cm2 C−1) but also exhibited high contrast of optical transmittance change (ΔT %) up to 85% at 787 nm and 30% at 391 nm. After over 1000 cyclic switches, the polymer films still exhibited excellent stability of electrochromic characteristics. [ABSTRACT FROM AUTHOR]

A novel trifluoromethyl-substituted bis(ether amine) monomer, 1,1-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane, was synthesized that led to a series of novel fluorinated polyimides via chemical imidization route when reacted with various commercially available aromatic tetracarboxylic dianhydrides. These polyimides were highly soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone and N, N -dimethylacetamide, and most of them could afford transparent, low-colored, and tough films. These polyimides exhibited glass-transition temperatures ( Tgs) of 227-269 °C and showed no significant decomposition below 500 °C under either nitrogen or air atmosphere. These polyimides had low dielectric constants of 2.87-3.17 at 10 kHz, low water uptake of 0.13%-0.58%, and an ultraviolet-visible absorption cutoff wavelength at 364-410 nm. For a comparative study, a series of analogous polyimides based on 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane were also prepared and characterized. [ABSTRACT FROM AUTHOR]

2,4-diaminotriphenylamine (2) was synthesized via the cesium fluoride-mediated aromatic substitution reaction of 1-fluoro-2,4-dinitrobenzene with diphenylamine, followed by palladium-catalyzed hydrazine reduction. A series of poly(amide-imide)s (PAIs) with inherent viscosities of 0.38–0.46 dL/g were prepared by triphenyl phosphite-activated polycondensation from the diamine monomer 2 with various monoimide- and diimide-dicarboxylic acids. All of the PAIs were readily soluble in a variety of organic solvents and formed strong and tough films via solution casting. These PAIs have moderately high glass transition temperatures in the range of 168–274 ○C and 10 % weight loss temperatures in excess of 447 ○C in nitrogen or in air. [ABSTRACT FROM AUTHOR]

A new N-phenylated amide (N-phenylamide) unit-containing aromatic diamine, 1,4-bis[N-(4-aminobenzoyl)-N-phenyl]phenylenediamine, was prepared by the condensation of NN-diphenyl-1,4-phenylenediamine with 4-nitrobenzoyl chloride, followed by catalytic reduction. Two series of aromatic poly(N-phenylamide-imide)s and poly(N-phenylamide-amide)s with inherent viscosities of 0.25-0.42 and 0.25-0.54 dL g-1 were prepared by a conventional two-stage method and the direct phosphorylation polycondensation, respectively, from the diamine with various aromatic dianhydrides and aromatic dicarboxylic acids. Some polymers based on rigid dianhydrides and diacids were semi-crystalline and insoluble in organic solvents. The other polymers were amorphous and organosoluble and could afford freestanding or tough films via solution casting. These polyimides and polyamides had glass transition temperatures in the range of 248-267 and 177-198C, respectively. Decomposition temperatures of the polyimides for 10% weight loss all occurred above 470C in both nitrogen and air atmospheres. [ABSTRACT FROM AUTHOR]

Two series of 2,7-naphthalenediyl units-containing homoand copoly(ester imide)s were prepared from 2,7-bis(4-aminobenzoyloxy)naphthalene and 2,7-bis(3-aminobenzoyloxy)naphthalene, respectively, with six commercially available aromatic tetracarboxylic dianhydrides and their mixtures 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 0.59∼1.15 and 0.51∼1.20 dL g-1, respectively. Some of the poly(ester imide)s derived from less rigid dianhydrides had excellent solubility in polar aprotic solvents such as N-methyl-2-pyrrolidone and N,N-dimethylacetamide and could be solution-cast into transparent, flexible, and tough films. The poly(ester imide)s derived from rigid dianhydrides such as pyromellitic dianhydride (PMDA) and 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA) were semicrystalline and showed less solubility. Except for some examples, most of the poly(ester imide)s displayed discernible glass-transition temperatures (T gs) between 233 and 295°C in the differential scanning calorimetry traces. These poly(ester imide)s showed insignificant decomposition below 450°C in nitrogen or air. The investigation of the thermal decomposition of the poly(ester imide)s using pyrolysis-gas chromatography/mass spectrometry (pyrolysis-GC/MS) indicated that a dramatic breakage of the ester linkages occurred at around 450°C, which initiated the polymer chain scission. [ABSTRACT FROM AUTHOR]

Two series of novel polyhydrazides and poly(amide-hydrazide)s are prepared from two ortho-linked bis(ether-carboxylic acid)s including 4,4′-(1,2-phenylenedioxy)dibenzoic acid and 4,4′-(4-tert-butyl-1,2-phenylenedioxy)dibenzoic acid, or their diacyl chlorides with terephthalic dihydrazide (TPH), isophthalic dihydrazide (IPH) and p-aminobenzoyl hydrazide (p-ABH) via the Yamazaki phosphorylation reaction or the low-temperature solution polycondensation. The resulting hydrazide-containing polymers exhibited inherent viscosities in the range of 0.27-0.62 dl g-1. These hydrazide polymers were amorphous and soluble in various solvents such as N-methyl-2-pyrrolidone (NMP), N,N-dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO) and could be solution-cast into colorless, flexible, and tough films with good tensile strengths. Differential scanning calorimetry (DSC) indicated that the polyhydrazides and poly(amide-hydrazide)s had Tg s in the range of 172-200 °C and could be thermally cyclodehydrated into the corresponding oxadiazole polymers in the range of 270-370 °C. The oxadiazole polymers showed a slightly enhanced crystallinity and Tg, but a dramatically decreased solubility compared to their hydrazide prepolymers. The thermally converted oxadiazole polymers exhibited Tg s in the range of 205-221 °C and softening temperatures of 214-239 °C and showed insignificant weight loss up to 450 °C in air or nitrogen. [ABSTRACT FROM AUTHOR]

A series of fluorinated polyimides were prepared from 1,1-bis[4-(4-aminophenoxy)phenyl]-1-2,2,2-trifluoroethane with various aromatic tetracarboxylic dianhydrides via a conventional two-step procedure. These polyimides were amorphous in nature and afforded flexible and tough films. Some polyimides derived from less stiff dianhydrides were soluble in polar organic solvents. The glass-transition temperatures (Tg) of these polyimides ranged from 252 to 324°C, and softening temperatures (Ts) stayed in the 254∼322°C range. Decomposition temperatures (Td) at 10% weight loss all occurred above 569°C in both air and nitrogen atmospheres. For a comparative study, another series of analogous polyimides based on 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane were also prepared and characterized. [ABSTRACT FROM AUTHOR]