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1.
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. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 247–260, 2000  相似文献   

2.
Two series of novel fluorinated aromatic polyamides were prepared from 1,1‐bis[4‐(4‐carboxyphenoxy)phenyl]‐1‐phenyl‐2,2,2‐trifluoroethane with various aromatic diamines or from 1,1‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐phenyl‐2,2,2‐trifluoroethane with various aromatic dicarboxylic acids with the phosphorylation polyamidation technique. These polyamides had inherent viscosities ranging from 0.51 to 1.54 dL/g that corresponded to weight‐average and number‐average molecular weights (by gel permeation chromatography) of 36,200–80,000 and 17,200–64,300, respectively. All polymers were highly soluble in aprotic polar solvents, such as N‐methyl‐2‐pyrrolidone and N,N‐dimethylacetamide, and some could even be dissolved in less‐polar solvents like tetrahydrofuran. The flexible and tough films cast from the polymer solutions possessed tensile strengths of 76–94 MPa and initial moduli of 1.70–2.22 GPa. Glass‐transition temperatures (Tg's) and softening temperatures of these polyamides were observed in the range of 185–268 °C by differential scanning calorimetry or thermomechanical analysis. Decomposition temperatures (Td's) for 10% weight loss all occurred above 500 °C in both nitrogen and air atmospheres. Almost all the fluorinated polyamides displayed relatively higher Tg and Td values than the corresponding nonfluorinated analogues. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 420–431, 2003  相似文献   

3.
A new dicarboxylic acid monomer, 1,1‐bis[4‐(4‐carboxyphenoxy)phenyl]‐4‐tert‐butylcyclohexane, bearing a pendent tert‐butylcyclohexylidene group was prepared in three steps from 4‐tert‐butylcyclohexanone. The monomer was reacted with various diamines to produce a series of new polyamides with triphenyl phosphite and pyridine as condensing agents. These polyamides were produced with inherent viscosities of 0.74 to 1.02 dL g−1. All the polymers were characterized by X‐ray diffraction that revealed this amorphous nature. These polymers exhibited excellent solubility in a variety of solvents. Almost all the polymers could be dissolved in N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide, dimethyl sulfoxide, pyridine, and even in tetrahydrofuran and cyclohexanone. These polymers showed glass‐transition temperatures between 223 and 256 °C and decomposition temperatures at 10% weight loss ranging from 468 to 491 °C and 469 to 498 °C in nitrogen and air atmospheres, respectively. Transparent, tough, and flexible films of these polymers were cast from the DMAc solutions. These polymer films had tensile strengths ranging from 76 to 99 MPa, elongations at break from 7 to 19%, and initial moduli from 2.1 to 2.7 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 797–803, 2000  相似文献   

4.
A series of new polyamides containing both sulfone and oxyethylene moieties in the polymer chain was prepared by the direct polycondensation of the diamine monomer 2,2‐bis[4‐[2‐(4‐aminophenoxy)ethoxy]phenyl]sulfone (BAEPS) and various aromatic dicarboxylic acids in N‐methyl‐2‐pyrrolidinone (NMP) using triphenyl phosphite and pyridine as condensing agents. Polymers were produced with inherent viscosities of 0.30–0.60 dl/g and identified by elemental analysis, and infrared and nuclear magnetic resonance spectra. Most of the polymers were readily dissolved in polar solvents such as NMP, dimethylsulfoxide, N,N‐dimethylacetamide, N,N‐dimethylformamide and m‐cresol at room temperature. Polymers containing rigid and symmetric p‐phenylene, naphthalene and p‐biphenylene moieties revealed a crystalline nature and showed no solubility in organic solvents. These polyamides had 10% weight loss temperatures ranging between 423 and 465 °C in nitrogen atmosphere and glass transition temperatures between 170 and 305 °C. The polymers with crystallinity nature exhibited melting endotherms (Tm) below 386 °C in differential scanning calorimetry trace. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

5.
Aromatic polyamides based on a novel bis(ether‐carboxylic acid) were synthesized by the direct phosphorylation condensation method. 1,4‐Bis(4‐carboxyphenoxy)‐2,5‐di‐tert‐butylbenzene was combined with various diamines containing flexible linkages and side substituents to render a set of eight novel aromatic polyamides. The polymers were produced with high yields and moderate to high inherent viscosities (0.49–1.32 dL/g) that corresponded to weight‐average and number‐average molecular weights (by gel permeation chromatography) of 31,000–80,000 and 19,000–50,000, respectively. Except for a single example, the polyamides were essentially amorphous and soluble in a variety of common solvents such as cyclohexanone, dioxane, and tetrahydrofuran. They showed glass‐transition temperatures of 250–295 °C (by differential scanning calorimetry) and 10% weight loss temperatures above 460 °C, as revealed by thermogravimetric analysis in nitrogen. Polymer films, obtained by casting from N,N‐dimethylacetamide solutions, exhibited good mechanical properties, with tensile strengths of 83–111 MPa and tensile moduli of 2.0–2.2 GPa. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 475–485, 2001  相似文献   

6.
A set of new aromatic polyamides were synthesized by the direct phosphorylation condensation of 4‐(1‐adamantyl)‐1,3‐bis‐(4‐aminophenoxy)benzene with various diacids. The polymers were produced with high yields and moderate to high inherent viscosities (0.43–1.03 dL/g), and the weight‐average molecular weights and number‐average molecular weights, determined by gel permeation chromatography, were in the range of 37,000–93,000 and 12,000–59,000, respectively. The polyamides were essentially amorphous and soluble in a variety of solvents such as N,N‐dimethylacetamide (DMAc), cyclohexanone, and tetrahydrofuran. They showed glass‐transition temperatures in the range of 240–300 °C (differential scanning calorimetry) and 10% weight‐loss temperatures over 450 °C, as revealed by thermogravimetric analysis in nitrogen. All the polymers gave strong films via casting from DMAc solutions, and these films exhibited good mechanical properties, with tensile strengths in the range of 77–92 MPa and tensile moduli between 1.5 and 2.5 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1014–1023, 2000  相似文献   

7.
A novel, trifluoromethyl‐substituted, bis(ether amine) monomer, 1,4‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene, was synthesized through the nucleophilic displacement of 2‐chloro‐5‐nitrobenzotrifluoride with 1,4‐dihydroxynaphthalene in the presence of potassium carbonate in dimethyl sulfoxide, followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of new fluorine‐containing polyimides with inherent viscosities of 0.57–0.91 dL/g were prepared by reacting the diamine with six commercially available aromatic dianhydrides via a conventional, two‐step thermal or chemical imidization method. Most of the resulting polyimides were soluble in strong polar solvents such as N‐methylpyrrolidone and N,N‐dimethylacetamide (DMAc). All the polyimides afforded transparent, flexible, and strong films with good tensile properties. These polyimides exhibited glass‐transition temperatures (Tg's) (by DSC) and softening temperatures (by thermomechanical analysis) in the ranges of 252–315 and 254–301 °C, respectively. Decomposition temperatures for 5% weight loss all occurred above 500 °C in both air and nitrogen atmospheres. The dielectric constants of these polyimides ranged from 3.03 to 3.71 at 1 MHz. In addition, a series of new, fluorinated polyamides with inherent viscosities of 0.32–0.62 dL/g were prepared by the direct polycondensation reaction the diamine with various aromatic dicarboxylic acids by means of triphenyl phosphite and pyridine. All the polyamides were soluble in polar solvents such as DMAc and could be solution‐cast into tough and flexible films. These polyamides had Tg's between 228 and 256 °C and 10% weight‐loss temperatures above 400 °C in nitrogen or air. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2377–2394, 2004  相似文献   

8.
A new N‐phenylated amide (N‐phenylamide) unit containing aromatic diamine, N,N′‐bis(3‐aminobenzoyl)‐N,N′‐diphenyl‐1,4‐phenylenediamine, was prepared by the condensation of N,N′‐diphenyl‐1,4‐phenylenediamine with 3‐nitrobenzoyl chloride, followed by catalytic reduction. Two series of organosoluble aromatic poly(N‐phenylamide‐imide)s and poly(N‐phenylamide‐amide)s with inherent viscosities of 0.58–0.82 and 0.56–1.21 dL/g 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. All polyimides and polyamides are amorphous and readily soluble in many organic solvents such as N,N‐dimethylacetamide and N‐methyl‐2‐pyrrolidone. These polymers could be solution cast into transparent, tough, and flexible films with high tensile strengths. These polyimides and polyamides had glass‐transition temperatures in the ranges of 230–258 and 196–229 °C, respectively. Decomposition temperatures of the polyimides for 10% weight loss all occurred above 500 °C in both nitrogen and air atmospheres. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2564–2574, 2002  相似文献   

9.
A new cardo dicarboxylic acid, 8,8‐bis[4‐(4‐carboxyphenoxy)phenyl]tricyclo[5.2.1.02,6]decane (BCPTD), was synthesized from 4,4′‐(octahydro‐4,7‐methano‐5H‐inden‐5‐ylidene)bisphenol and p‐fluorobenzonitrile via aromatic nucleophilic substitution followed by hydrolysis. A series of new cardo polyamides was prepared by the direct polycondensation of BCPTD and various aromatic diamines in N‐methyl‐2‐pyrrolidinone (NMP) with triphenyl phosphite and pyridine as the condensing agents. Polymers were produced with moderate to high inherent viscosities of 0.65 to 1.08 dL g−1. The polymers, except for polymer PA1 , exhibited number‐average molecular weights and weight‐average molecular weights in the range of 38,400 to 86,300 and 57,800 to 148,000, respectively. Nearly all of the polymers were readily soluble in polar solvents such as NMP, N,N‐dimethylacetamide, N,N‐dimethylformamide, and dimethyl sulfoxide as well as in less polar solvents such as pyridine, γ‐butyrolactone, and tetrahydrofuran. All of the polymers were amorphous, and the polyamide films had a tensile‐strength range of 75 to 128 MPa and a tensile‐modulus range of 2.0 to 2.8 GPa. These polyamides had glass‐transition temperatures between 240 and 269°C and 10% weight‐loss temperatures in the range of 477 to 508°C and 471 to 518°C in nitrogen and air atmospheres, respectively. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 74–79, 2000  相似文献   

10.
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  相似文献   

11.
A new triphenylamine‐containing aromatic diamine, N, N′‐bis(4‐aminophenyl)‐N, N′‐diphenyl‐1,4‐phenylenediamine, was prepared by the condensation of N,N′‐diphenyl‐1,4‐phenylenediamine with 4‐fluoronitrobenzene, followed by catalytic reduction. A series of novel aromatic polyamides with triphenylamine units were prepared from the diamine and various aromatic dicarboxylic acids or their diacid chlorides via the direct phosphorylation polycondensation or low‐temperature solution polycondensation. All the polyamides were amorphous and readily soluble in many organic solvents such as N, N‐dimethylacetamide and N‐methyl‐2‐pyrrolidone. These polymers could be solution cast into transparent, tough, and flexible films with good mechanical properties. They had useful levels of thermal stability associated with relatively high glass‐transition temperatures (257–287 °C), 10% weight‐loss temperatures in excess of 550 °C, and char yields at 800 °C in nitrogen higher than 72%. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2810–2818, 2002  相似文献   

12.
A series of novel polyamide‐imides III containing 2,6‐bis(phenoxy)naphthalene units were synthesized by 2,6‐bis(4‐aminophenoxy)naphthalene and various bis(trimellitimide)s in N‐methyl‐2‐pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents through direct polycondensation. The polymers were obtained in quantitative yield with inherent viscosities up to 1.53 dL/g. Most of the polymers showed good solubility in NMP, N,N‐dimethylacetamide, N,N‐dimethylformamide, and dimethyl sulfoxide and could be solution‐cast into transparent, flexible, and tough films. The films had tensile strengths of 84–111 MPa, elongations at break of 8–33%, and initial moduli of 2.2–2.8 GPa. Wide‐angle X‐ray diffraction revealed that most polymers III were amorphous. The glass‐transition temperatures of some of the polymers could be determined by differential scanning calorimetry traces, recorded at 247–290 °C. The polyamide‐imides exhibited excellent thermal stabilities and had 10% weight loss at temperatures in the range of 501–575 °C under nitrogen atmosphere. They left more than 57% residue even at 800 °C in nitrogen. A comparative study of some corresponding polyamide‐imides is also presented. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2591–2601, 2001  相似文献   

13.
A series of new strictly alternating aromatic poly(ester‐imide)s having inherent viscosities of 0.20–0.98 dL/g was synthesized by the diphenylchlorophosphate (DPCP) activated direct polycondensation of the preformed imide ring‐containing diacid, 3,3‐bis[4‐(trimellitimidophenoxy)phenyl]phthalide (I), with various bisphenols in a medium consisting of pyridine and lithium chloride. The diimide–diacid I was prepared from the condensation of 3,3‐bis[4‐(4‐aminophenoxy)phenyl]phthalide and trimellitic anhydride. Most of the resulting polymers showed an amorphous nature and were readily soluble in a variety of organic solvents such as N‐methyl‐2‐pyrrolidone (NMP) and N,N‐dimethylacetamide (DMAc). Transparent and flexible films of these polymers could be cast from their DMAc solutions. The cast films had tensile strengths ranging 66–105 MPa, elongations at break from 7–10%, and initial moduli from 1.9–2.4 GPa. The glass‐transition temperatures of these polymers were recorded between 208–275 °C. All polymers showed no significant weight loss below 400 °C in the air or in nitrogen, and the decomposition temperatures at 10% weight loss all occurred above 460 °C. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1090–1099, 2000  相似文献   

14.
New aromatic tetracarboxylic dianhydride, having isopropylidene and bromo‐substituted arylene ether structure 3,3′,5,5′‐tetrabromo‐2,2‐bis[4‐(3,4‐dicarboxyphenoxy)phenyl]propane dianhydride, was synthesized by the reaction of 4‐nitrophthalonitrile with 3,3′,5,5′‐tetrabromobisphenol A, followed by alkaline hydrolysis of the intermediate bis(ether dinitrile) and subsequent dehydration of the resulting bis(ether diacid). The novel aromatic polyetherimides having inherent viscosities up to 1.04 dL g−1 were obtained by either a one‐step or a conventional two‐step polymerization process starting from the bis(ether anhydride) and various aromatic diamines. All the polyimides showed typical amorphous diffraction patterns. Most of the polyimides were readily soluble in common organic solvents such as N,N‐dimethylacetamide (DMAc), N‐methyl‐2‐pyrrolidone (NMP), pyridine, and even in less polar solvents like chloroform and tetrahydrofuran (THF). These aromatic polyimides had glass transition temperatures in the range of 256–303°C, depending on the nature of the diamine moiety. Thermogravimetric analysis (TGA) showed that all polymers were stable, with 10% weight loss recorded above 470°C in nitrogen. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1673–1680, 1999  相似文献   

15.
Jiang  Jianwen  Huang  Shuiping  Liu  Yuan  Sheng  Shouri  Huang  Zhenzhong  Song  Caisheng 《中国化学》2010,28(1):102-110
9,9‐Bis(4‐hydroxyphenyl)xanthene (BHPX) was synthesized in 82% yield from xanthenone in a one‐pot, two‐step synthetic procedure. A new diacyl chloride monomer, 9,9‐bis[4‐(chloroformylphenoxy)phenyl]xanthene (BCPX), was synthesized in three steps from the nucleophilic fluorodisplacement of 4‐fluorobenzonitrile with the dipotassium bisphenolate of BHPX, followed by alkaline hydrolysis of the intermediate bis(ether nitrile), and then chlorination with thionyl chloride. Several novel aromatic polyamides containing ether and bulky xanthene groups with the inherent viscosities (0.72–0.98 dL/g) were prepared by the low temperature polycondensation of BCPX with various aromatic diamines in N,N‐dimethylacetamide (DMAc) solution containing pyridine (Py). All new polyamides were amorphous and readily soluble in various polar solvents such as DMAc, N,N‐dimethylformamide (DMF), N‐methyl‐2‐pyrrolidone (NMP) and Py. These polymers showed relatively high glass transition temperatures between 236 and 298°C, decomposition temperatures at 10% weight loss ranging from 490 to 535°C and 483 to 515°C in nitrogen and air, respectively, and char yields at 700°C in nitrogen higher than 50%. Transparent, flexible, and tough films of these polymers cast from DMAc solutions exhibited tensile strengths ranging from 82 to 106 MPa, elongations at break from 10% to 25%, and initial moduli from 2.0 to 2.8 GPa.  相似文献   

16.
A new diimide‐dicarboxylic acid, 2,2′‐dimethyl‐4,4′‐bis(4‐trimellitimidophenoxy)biphenyl (DBTPB), containing a noncoplanar 2,2′‐dimethyl‐4,4′‐biphenylene unit was synthesized by the condensation reaction of 2,2′‐dimethyl‐4,4′‐bis(4‐minophenoxy)biphenyl (DBAPB) with trimellitic anhydride in glacial acetic acid. A series of new polyamide‐imides were prepared by direct polycondensation of DBAPB and various aromatic diamines in N‐methyl‐2‐pyrrolidinone (NMP), using triphenyl phosphite and pyridine as condensing agents. The polymers were produced with high yield and moderate to high inherent viscosities of 0.86–1.33 dL · g−1. Wide‐angle X‐ray diffractograms revealed that the polymers were amorphous. Most of the polymers exhibited good solubility and could be readily dissolved in various solvents such as NMP, N,N‐dimethylacetamide (DMAc), N,N‐dimethylformamide (DMF), dimethyl sulfoxide, pyridine, cyclohexanone, and tetrahydrofuran. These polyamide‐imides had glass‐transition temperatures between 224–302 °C and 10% weight loss temperatures in the range of 501–563 °C in nitrogen atmosphere. The tough polymer films, obtained by casting from DMAc solution, had a tensile strength range of 93–115 MPa and a tensile modulus range of 2.0–2.3 GPa. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 63–70, 2001  相似文献   

17.
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  相似文献   

18.
A new triphenylamine‐containing aromatic diamine monomer, N,N‐bis(4‐aminophenyl)‐N,N′‐bis(4‐tert‐butylphenyl)‐1,4‐phenylenediamine, was synthesized by an established synthetic procedure from readily available reagents. A novel family of electroactive polyamides with di‐tert‐butyl‐substituted N,N,N,N′‐tetraphenyl‐1,4‐phenylenediamine units were prepared via the phosphorylation polyamidation reactions of the newly synthesized diamine monomer with various aromatic or aliphatic dicarboxylic acids. All the polymers were amorphous with good solubility in many organic solvents, such as N‐methyl‐2‐pyrrolidinone (NMP) and N,N‐dimethylacetamide, and could be solution‐cast into tough and flexible polymer films. The polyamides derived from aromatic dicarboxylic acids had useful levels of thermal stability, with glass‐transition temperatures of 269–296 °C, 10% weight‐loss temperatures in excess of 544 °C, and char yields at 800 °C in nitrogen higher than 62%. The dilute solutions of these polyamides in NMP exhibited strong absorption bands centered at 316–342 nm and photoluminescence maxima around 362–465 nm in the violet‐blue region. The polyamides derived from aliphatic dicarboxylic acids were optically transparent in the visible region and fluoresced with a higher quantum yield compared with those derived from aromatic dicarboxylic acids. The hole‐transporting and electrochromic properties were examined by electrochemical and spectro‐electrochemical methods. Cyclic voltammograms of the polyamide films cast onto an indium‐tin oxide‐coated glass substrate exhibited two reversible oxidation redox couples at 0.57–0.60 V and 0.95–0.98 V versus Ag/AgCl in acetonitrile solution. The polyamide films revealed excellent elcterochemical and electrochromic stability, with a color change from a colorless or pale yellowish neutral form to green and blue oxidized forms at applied potentials ranging from 0.0 to 1.2 V. These anodically coloring polymeric materials showed interesting electrochromic properties, such as high coloration efficiency (CE = 216 cm2/C for the green coloring) and high contrast ratio of optical transmittance change (ΔT%) up to 64% at 424 nm and 59% at 983 nm for the green coloration, and 90% at 778 nm for the blue coloration. The electroactivity of the polymer remains intact even after cycling 500 times between its neutral and fully oxidized states. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2330–2343, 2009  相似文献   

19.
A new triphenylamine‐containing diamine monomer, 4,4′‐diamino‐4″‐tert‐butyltriphenylamine, was successfully synthesized by the cesium fluoride‐mediated N,N‐diarylation of 4‐tert‐butylaniline with 4‐fluoronitrobenzene, followed by the reduction of the nitro group. The obtained diamine monomer was reacted with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to produce two series of novel triphenylamine‐based polyamides and polyimides with pendent tert‐butyl substituents. Most of the polymers were readily soluble in polar organic solvents, such as N‐methyl‐2‐pyrrolidone and N,N‐dimethylacetamide (DMAc), and could be solution cast into tough and flexible polymer films. These polymers showed high glass transition temperatures between 282 and 320 °C, and they were fairly stable up to a temperature above 450 °C (for polyamides) or 500 °C (for polyimides). These polymers exhibited UV absorption maxima around 308 to 361 nm. The photoluminescence spectra of the polyamides in DMAc exhibited a peak emission wavelength in the blue at 421–433 nm. Cyclic voltammograms of polyamides and polyimides showed an oxidation wave at 1.0–1.1 V versus Ag/AgCl in an acetonitrile solution. All the polyamides and polyimides exhibited excellent reversibility of electrochromic characteristics by continuous several cyclic scans between 0.0 and 1.1–1.3 V, with a color change from the original pale yellowish neutral form to the green or blue oxidized forms. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4579–4592, 2006  相似文献   

20.
A dicarboxylic acid {1,1‐bis[4‐(4‐trimellitimidophenoxy)phenyl]‐1‐phenylethane ( II )} bearing two performed imide rings was prepared from the condensation of 1,1‐bis[4‐(4‐aminophenoxy)phenyl]‐1‐phenylethane and trimellitic anhydride in a 1/2 molar ratio. A novel family of poly(amide‐imide)s with inherent viscosities of 0.83–1.51 dL/g was prepared by triphenyl phosphite‐activated polycondensation from the diimide‐diacid II with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidinone (NMP), pyridine, and calcium chloride. Because the 1,1,1‐triphenylethane group of II was unsymmetrical, most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded tough, transparent, and flexible films, which had tensile strengths ranging from 88 to 102 MPa, elongations at break from 6 to 11%, and initial moduli from 2.23 to 2.71 GPa. The synthesized poly(amide‐imide)s possessed glass‐transition temperatures from 250 to 287 °C. The poly(amide‐imide)s exhibited excellent thermal stabilities and had 10% weight losses from 501 to 534 °C under a nitrogen atmosphere. A comparative study of some corresponding poly(amide‐imide)s is also presented. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 775–787, 2001  相似文献   

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