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1.
N,N′-Pyromelliticdiimido-di-l-methionine (3) was prepared from the reaction of pyromellitic dianhydride (1) with l-methionine (2) in glacial acetic acid and pyridine solution at refluxing temperature. The direct polycondensation reaction of the monomer diimide-diacid (3) with 1,3-phenylenediamine (4a), 1,4-phenylenediamine (4b), 2,6-diaminopyridine (4c), 3,5-diaminopyridine (4d), 4,4′-diaminodiphenylether (4e) and 4,4′-diaminodiphenylsulfone (4f) was carried out in a medium consisting of triphenyl phosphate, N-methyl-2-pyrolidone, pyridine and calcium chloride. The resulting poly(amide-imide)s having inherent viscosities 0.45-0.53 dl g−1 were obtained in high yields and are optically active and thermally stable. All of the above compounds were fully characterized by IR spectroscopy, elemental analyses and specific rotation. Some structural characterization and physical properties of these new optically active poly(amide-imide)s are reported.  相似文献   

2.
Six new optically active poly(amide-imide)s(5a-f) were synthesized through the direct polycondensation reaction of N,N'-(4,4'- diphthaloyl)-bis-L-leucine(3) with six hydantoin derivatives(4a-f).Triphenyl phosphite(TPP)/pyridine in the presence of calcium chloride(CaCl_2) and N-methyl-2-pyrrolidone(NMP) were successfully applied for direct polycondensation.The polycondensation reactions produce a series of new poly(amide-imide)s(5a-f) in high yields,and inherent viscosity between 0.42 and 0.55 dL/g.The re...  相似文献   

3.
4,4-(Hexafluoroisopropylidene)-N,N-bis(phthaloyl-l-leucine-p-amidobenzoic acid) (2) was prepared from the reaction of 4,4-(hexafluoroisopropylidene)-N,N-bis(phthaloyl-l-leucine) diacid chloride with p-aminobenzoic acid. The direct polycondensation reaction of monomer (2) with p-phenylenediamine (2a), 4,4-diaminodiphenylsulfone (2b), 2,4-diaminotoluene (2c), 2,6-diaminopyridine (2d), m-phenylene diamine (2e), benzidine (2f), 4,4-diaminodiphenylether (2g) and 4,4-diaminodiphenyl methane (2h) was carried out in a medium consisting of triphenyl phosphite, N-methyl-2-pyrolidone, pyridine, and calcium chloride. The homogeneous mixture was heated at 220 °C for 1 min under nitrogen. The resulting poly(amide-imide)s (PAIs) having inherent viscosities 0.27-0.78 dl/g were obtained in high yield and are optically active and thermally stable. All of the above polymers were fully characterized by IR spectroscopy, elemental analyses and specific rotation. Some structural characterization and physical properties of this new optically active PAIs are reported.  相似文献   

4.
Six new photosensitive and optically active poly(amide-imide)s 8a8f with good inherent viscosities based on dibenzalacetone moiety were synthesized from the direct polycondensation reaction of N-Trimellitylimido-L-amino acids 3a3f with 2,5-bis(4-aminobenzylidene)cyclopentanone 7 by two different methods such as direct polycondensation in a medium consisting of N-methyl-2-pyrrolidone/triphenyl phosphite/calcium chloride/pyridine and direct polycondensation in a tosyl chloride/pyridine (py)/N,N-dimethylformamide system. Diamine 7 was synthesized by using a two-step reaction. At first 2,5-bis(4-nitrobenzylidene)cyclopentanone 6 was prepared from the reaction of two equimolars 4-nitrobenzaldehyde 5 and one equimolar cyclopentanone 4 and dinitro compound 6 was reduced by using Na2S. Also N-trimellitylimido-L-amino acids 3a3f were synthesized by the condensation reaction of trimellitic anhydride 1 with two equimolars of various L-amino acids 2a2f in an acetic acid solution. The polymerization reactions produced a series of photosensitive and optically active poly(amide-imide)s with high yield and good inherent viscosity. The resulted polymers were fully characterized by means of FTIR and 1H-NMR spectroscopy, elemental analyses, inherent viscosity, specific rotation, solubility tests, UV-VIS spectroscopy, differential scanning calorimeter, thermogravimetric analysis, and derivative of thermogravimetric. These macromolecules exhibited maximum UV-VIS absorption at around 395 and 265 nm in a N,N-dimethylformamide solution.  相似文献   

5.
Rapid and highly efficient synthesis of novel optically active poly(amide-imide)s (PAIs) 6(a-f) was achieved using microwave irradiation. These were made from the polycondensation reactions of 4,4-carbonyl-bis(phthaloyl-l-alanine) diacid chloride [N,N-(4,4-carbonyldiphthaloyl)] bisalanine diacid chloride 5 with six different derivatives of hydantoin and thiohydantoin compounds 4(a-f) in the presence of a small amount of a nonpolar organic medium that acts as a primary microwave absorber. Hydantoin and thiohydantoin derivatives 4(a-e) were synthesis from the reactions between benzil or benzil derivatives 3(a-e) with urea and thiourea. 5,5-Dimethylhydantoin 4f was synthesis from the reactions between acetone cyanohydrin 3f and ammonium carbonate. The polycondensation proceeded rapidly, and was completed within 10 min giving a series of PAIs with an inherent viscosity about 0.25-0.45 dL/g. The resulting PAIs 6(a-f) were obtained in a high yield and were optically active and thermally stable. All of the above compounds were fully characterized by means of Fourier transform infrared spectroscopy, elemental analyses, inherent viscosity (ηinh), solubility tests and specific rotation. Thermal properties of the PAIs 6(a-f) were investigated using thermal gravimetric analysis.  相似文献   

6.
Reaction of 5-amino-1-naphthol with 2,6-dichloropyridine resulted in preparation of 2,6-bis(5-amino-1-naphthoxy) pyridine (AN). This pyridine-based ether diamine was reacted with two moles of trimellitic anhydride (TMA) to synthesize related diimide-diacid (DIDA). Direct polycondensation reaction of DIDA with different diamines in the presence of triphenyl phosphite (TPP) afforded seven different poly(amide-imide)s. All the polymers were characterized and their physical and thermal properties were studied. The inherent viscosity of the polymers was about 0.44-0.50 dl g−1 and they showed high thermal stability.  相似文献   

7.
<正>A series of new optically active poly(amide-imide)s were synthesized by direct polycondensation reaction of 4,4'-diaminochalcone with several N-trimellitylimido-L-amino acids using a tosyl chloride(TsCl),pyridine(Py) and dimethylformamide(DMF) system as condensing agent.The resulting thermally stable poly(amide-imide)s were obtained in good to high yields and inherent viscosities ranging between 0.35 dL/g and 0.58 dL/g and were characterized with FTIR, ~1H-NMR,CHN,Ultraviolet,TGA and DTG techniques.  相似文献   

8.
Syntheses and polycondensations of optically active hydroxycarboxylic acids prepared from acid anhydrides and aminoalcohols were carried out. Novel polymers with M̄n 9900–27,200 were obtained by the polycondensations of hydroxycaboxylic acids derived from maleic or succinic acid using 1.2 eq. of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC · HCl) in DMF (2M) at room temperature for 8 h in satisfactory yields. Meanwhile, a hydroxycarboxylic acid obtained from phthalic acid afforded no polymer but a phthalimide derivative. The radical additions of ethanethiol or mercaptoethanol with the polymers derived from maleic anhydride proceeded smoothly in satisfactory incorporation ratios (65–98%), respectively. The polymer obtained from succinic anhydride and 2-aminoethanol showed hydrolytic degradability. © 1997 John Wiley & Sons, Inc.  相似文献   

9.
A series of ethyl(phenyl) 6-amino-2,3,6-trideoxy--D-glucopyranosides (amino=piperidino (Pip), pyrrolidino (Pyr), azetidino (Az), Bu2N) have been prepared from tri-O-acetyl-D-glucal to obtain catalysts for asymmetric synthesis and the starting compounds for the syntheses of other bidentate ligands.Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 45–52, January, 2000.  相似文献   

10.
Novel aromatic poly(amide-imide)s with high inherent viscosities were prepared by direct polycondensation reaction of 2,5-bis(4-trimellitimidophenyl)-3,4-diphenylthiophene ( IV ) and aromatic diamines using triphenyl phosphite in the N-methyl–2-pyrrolidone (NMP)/pyridine solution containing dissolved CaCl2. The diimide-diacid IV was readily obtained by the condensation reaction of 2,5-bis(4-aminophenyl)-3,4-diphenylthiophene ( III 1) with trimellitic anhydride. The obtained poly(amide-imide)s showed high thermostability. Their decomposition temperatures at 10% weight loss in nitrogen atmospheres were above 550°C and the anaerobic char yield at 800°C ranged from 48 to 68%. Almost all the poly(amide-imide)s showed high glass transition temperatures above 300°C by differential scanning calorimetry (DSC) measurements. These polymers were readily soluble in various organic solvents and could be cast into transparent, tough, and flexible films. Their casting films showed obvious yield points in the stress-strain curves and had strength at break up to 74.2 MPa, elongation to break up to 70.1%, and initial modulus up to 4.56 GPa. The factors affecting the reaction of diimide-diacid IV and 4,4′-oxydianiline in view of monomer concentration, reaction temperature, and amount of CaCl2 were also investigated. © 1992 John Wiley & Sons, Inc.  相似文献   

11.
Eleven bis(phenoxy) naphthalene-containing poly(amide-imide)s IIIa–k were synthesized by the direct polycondensation of 2,7-bis (4-aminophenoxy) naphthalene (DAPON) with various aromatic bis (trimellitimide)s IIa–k in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly (amide-imide)s IIIa–k having inherent viscosities of 0.70–1.12 dL/g were obtained in quantitative yields. The polymers containing p-phenylene or bis(phenoxy) benzene units exhibited crystalline x-ray diffraction patterns. Most of the polymers were readily soluble in various solvents such as NMP, N, N-dimethylacetamide, dimethyl sulfoxide, m-cresol, o-chlorophenol, and pyridine, and gave transparent, and flexible films cast from DMAc solutions. Cast films showed obvious yield points in the stress-strain curves and had strength at break up to 87 MPa, elongation to break up to 11%, and initial modulus up to 2.10 GPa. These poly(amide-imide)s had glass transition temperatures in the range of 255–321°C, and the 10% weight loss temperatures were recorded in the range of 529–586°C in nitrogen. The properties of poly(amideimide)s IIIa–k were compared with those of the corresponding isomeric poly (amide-imide)s III′ prepared from 2,7-bis(4-trimellitimidophenoxy) naphthalene and aromatic diamines. © 1994 John Wiley & Sons, Inc.  相似文献   

12.
Six new optically active poly(amide-imide)s(PAIs) 6a-f were prepared by direct polycondensation reaction of N-trimelli-tylimido-L-histidine 4 as a chiral diacid with various aromatic diamines 5a-f.Triphenyl phosphite(TPP)/pyridine(Py) in the presence of calcium chloride(CaCl2) and N-methyl-2-pyrrolidone(NMP) were successfully applied to direct polycondensation reaction.The resulting new polymers were in good yields,and had inherent viscosities ranging between 0.29 and 0.41 dL g-1 and were detected with elem...  相似文献   

13.
A series of polyamides and poly(amide-imide)s were prepared by the direct poly-condensation of 2,2-bis(4-aminophenoxy) benzonitrile [4-APBN] with aromatic dicarboxylic acids and bis(carboxyphthalimide)s in N-methyl-2-pyrrolidone [NMP] with triphenyl phosphite and pyridine as condensing agents. The synthesis of 4-APBN involves a nucleophilic displacement reaction in dipolar aprotic solvent with the alkali metal salt of p-aminophenol and an activated aromatic dichloro compound. Bis(carboxyphthalimide)s were prepared by condensation of 4,4-diaminodiphenylsulfone, 3,3-diaminodiphenylsulfone, 4,4-diaminodiphenylether, 4,4-diaminodiphenylmethane, 3,3-diaminobenzophenone, and trimellitic anhydride at a 1:2 molar ratio. The inherent viscosities of the resulting polymers were found to be in the range of 0.31-0.93 dl/g and glass transition temperatures between 235 and 298 °C. All polymers were soluble in aprotic polar solvents such as dimethylsulfoxide and NMP. The results of thermogravimetry revealed that all the polymers showed no significant weight loss before 400 °C. Wide-angle X-ray diffractograms revealed that all polymers were found to be amorphous except for the polyamide derived from isophthalic acid and polyamide-imides derived from diaminodiphenylether and diaminobenzophenone based bis(carboxyphthalimide)s.  相似文献   

14.
In this research a new diimide-diacid monomer, 2,2′-bis(4-phenoxyphenyl)-4,4′-bis(N-trimellitoyl)diphenyl ether (BPDPE) containing two laterally-attached phenoxy phenylene groups was prepared by the reaction of 2,2′-bis[(p-phenoxy phenyl)]-4,4′-diaminodiphenyl ether (PPAPE) with trimellitic anhydride in refluxing glacial acetic acid. Ether-hinged wholly aromatic poly(amide-imide)s with limited viscosity number values of 0.61–0.87 dL g−1 were prepared by triphenyl phosphate (TPP)-activated polycondensation of BPDPE with diamines including PPAPE and 4,4′-diaminodiphenyl ether (DADPE). For comparative purposes, reference poly(amide-imide)s were also prepared by reacting diimide-diacid monomer lacking phenoxy phenylene lateral groups namely 4,4′-bis(N-trimellitoyl)diphenyl ether (BTDPE) with the same diamines under similar conditions. A model compound MODEL was also synthesized by the reaction of BTBPE with two mole equivalents of aniline to compare the spectral characteristics results. Number and weight average molecular weights were determined by gel permeation chromatography (GPC) technique. The phenoxy phenylene-containing poly(amide-imide)s (all, except that of resulted from BTDPE and DADPE) had excellent organosolubility in common polar solvents. A low crystallinity extent was only observed using their wide-angle X-ray diffractograms (WAXD). A qualitative study showed the prepared polymers could also be cast into optically-transparent and flexible thin films. The ether-containing lateral groups attached to the ether-hinged macromolecular main chains had no substantial diminishing effect on the thermal stability of these structurally-modified poly(amide-imide)s.  相似文献   

15.
New bis(phenoxy)naphthalene-containing poly(amide-imide)s having an inherent viscosity in the range of 0.62–1.09 dL/g were prepared by the direct polycondensation of 1,5-bis(4-trimellitimidophenoxy) naphthalene ( I ) and various aromatic diamines using triphenyl phosphite and pyridine as condensing agents in N-methyl-2-pyrrolidone (NMP) in the presence of calcium chloride. The diimide-diacid (I) was prepared by the condensation of 1,5-bis(4-aminophenoxy) naphthalene and trimellitic anhydride. Most of the polymers were soluble in aprotic solvents such as NMP and N,N-dimethylacetamide (DMAc), and afforded transparent, flexible and tough films upon casting from DMAc solutions. Measurements of wide-angle X-ray diffraction revealed that those polymers containing p-phenylene or oxyphenylene groups were characterized as crystalline polymers. Tensile strength and initial moduli of the polymer films ranged from 61–86 MPa and 1.83–2.21 GPa, respectively. Glass transition temperatures of the polymers were in the range of 231–340°C. The melting points of the crystalline polymers ranged from 375–430°C. The 10% weight loss temperatures were above 512°C in nitrogen and 481°C in air. © 1993 John Wiley & Sons, Inc.  相似文献   

16.
The new polymer-forming diimide-diacid, 2,3-bis(4-trimellitimidophenoxy) naphthalene (I), was readily obtained by the condensation reaction of 2,3-bis (4-aminophenoxy) naphthalene with trimellitic anhydride. A series of novel aromatic poly (amide-imide)s were prepared by the direct polycondensation of diimide-diacid I with various aromatic diamines using triphenyl phosphite in N-methyl-2-pyrrolidone (NMP)/pyridine solution containing dissolved calcium chloride. The resultant polymers have inherent viscosities in the range of 0.65–1.02 dL/g at 30°C in N, N-dimethylacetamide. These polymers were readily soluble in various organic solvents and could be cast into transparent, tough, and flexible films. Their casting films showed tensile strength at break up to 86 MPa, elongation to break of 5–9%, and initial moduli up to 2.35 GPa. The wide-angle X-ray diffraction revealed that those polymers containing p-phenylene or p-oxyphenylene group are partially crystalline, and the other polymers are evidenced as amorphous patterns. These polymers show a glass transition in the range of 213–290°C in their differential scanning calorimetry (DSC) traces. The thermal stability of the polymers was evaluated by thermogravimetry analysis, which showed the 10% weight-loss temperatures in the range of 508–565°C in nitrogen and 480–529°C in air atmosphere. © 1994 John Wiley & Sons, Inc.  相似文献   

17.
A series of novel bis(phenoxy)phthalimidine-containing poly(amide-imide)s III were synthesized by the direct polycondensation of 3,3-bis[4-(4-aminophenoxy)phenyl]phthalimidine (BAPP) with various aromatic bis(trimellitimide)s in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. Poly(amide-imide)s III , having inherent viscosities up to 1.36 dL/g, were obtained in quantitative yields. All 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 transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 267–322°C and the 10% weight loss temperatures were above 490°C in nitrogen. Some properties of poly(amide-imide)s III were compared with those of the corresponding isomeric poly(amide-imide)s III′ prepared from 3,3-[4-(4-trimellitimidophenoxy)phenyl]-phthalimidine and various aromatic diamines. © 1996 John Wiley & Sons, Inc.  相似文献   

18.

The main aim of this research was to study the electrochemical behavior of novel optically active poly(amide-imide)s (PAIs). Polycondensation reactions of a 3,5-diamino-N-(4-hydroxyphenyl)benzamide with different synthetic diacid chlorides derivatives based on natural amino acids resulted in preparation of five different aromatic–aliphatic PAIs. These polymers were characterized by Fourier transform infrared, proton nuclear magnetic resonance, and elemental analyses. Also, we used electrochemical impedance spectroscopy for the evaluation of these novel optically active PAIs for the first time. Presence of p-substituted phenol groups in the structure of these polymers has been used for electrochemical investigation. Results showed that the oxidation currents in five diverse polymers were affected by their structures. In addition, the influence of carbon nanotubes on the oxidation of phenolic groups was studied using carbon paste matrix in an aqueous buffer solution (pH 7.0).

  相似文献   

19.
3,3,4,4-benzophenonetetracarboxylic dianhydride (4,4-carbonyldiphthalic anhydride) (1) was reacted with l-phenylalanine (2) in a mixture of acetic acid and pyridine (3:2) and the resulting imide-acid [N,N-(4,4-carbonyldiphthaloyl)-bis-l-phenylalanine diacid] (4) was obtained in high yield. The compound (4) was converted to the N,N-(4,4-carbonyldiphthaloyl)-bis-l-phenylalanine diacid chloride (5) by reaction with thionyl chloride. A new facile and rapid polycondensation reaction of this diacid chloride (5) with several aromatic diamines such as 4,4-diaminodiphenyl methane (6a), 2,4-diaminotoluene (6b), 4,4-sulfonyldianiline (6c), p-phenylenediamine (6d), 4,4-diaminodiphenylether (6e), m-phenylenediamine (6f), benzidine (6g) and 2,6-diaminopyridine (6h) was developed by using a domestic microwave oven in the presence of a small amount of a polar organic medium such as o-cresol. The polymerization reactions proceeded rapidly, compared with the conventional solution polycondensation, and was completed within 7 min, producing a series of optically active poly(amide-imide)s with high yield and inherent viscosity of 0.22-0.52 dl/g. All of the above polymers were fully characterized by IR, elemental analyses and specific rotation. Some structural characterization and physical properties of this optically active poly(amide-imide)s are reported.  相似文献   

20.
<正>A novel calix[4]arene derivative 2 with amino functional groups at the lower rim was first prepared via introduction of nitro functional groups and amination of the dinitro derivative of calix[4]arene.The optically active monomers were synthesized by dehydration of L-leucine(and L-isoleucine) and 3,3',4,4'-benzophenonetetracarboxylic- 3,3',4,4'-dianhydride(3) followed by reaction with thionyl chloride to form 5a and 5b.Two methods,polymerization under microwave irradiation and solution polymerization in CH_2Cl_2/TEA,were then employed to carry out the condensation polymerization of 2 with the optically active monomers 5a and 5b,respectively.The polymerization conditions affected the kind of resulting polymers,poly(amide-imide)s(PAIs) 6a and 6b and poly(ester-imide)s(PEIs) 6a' and 6b' were obtained selectively in good yields and moderate inherent viscosities.Sorption-extraction experiments were carried out using cram picrate extraction method and verified good binding ability of the resulting calixarene-based polymers towards silver,alkali metal and toxic heavy metal cations.Also thermogravimetric analysis indicated that the resulting PAIs and PEIs were thermally stable.  相似文献   

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