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1.
Fluorine-containing polyarylates having inherent viscosities of 0.2–0.8 dL/g were prepared from tetrafluoroisophthaloyl chloride and various bisphenols by low temperature solution polycondensation in chloroform with triethylamine or by two-phase polycondensation in a dichloromethane-water or nitrobenzene-water system with benzyltriethylammonium chloride as the phase transfer catalyst. These polyarylates were amorphous and were readily soluble in various solvents, including chloroform and N-methyl-2-pyrrolidone. The glass transition temperature of the polymer derived from 2,2-bis(4-hydroxyphenyl) propane was 150°C. These polyarylates started to lose weight around 350°C in an air or nitrogen atmosphere.  相似文献   

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3.
Polyarylates containing a t-butyl pendant group were prepared from 5-t-butylisophthaloyl chloride and various bisphenols through the phase-transfer catalyzed two-phase polycondensation. The polyarylates having inherent viscosities up to 3.1 dL/g were obtained quantitatively. They were readily soluble in various solvents such as chloroform, m-cresol, and pyridine. Coloreless, transparent, and flexible films could be cast from the chloroform solutions of the polymers. The polyarylates had glass transition temperatures between 210 and 320°C, and did not lose weight below 350°C, with 10% weight loss being recorded at 395–450°C in air.  相似文献   

4.
Polyarylates having inherent viscosities up to 1.02 dL/g were synthesized both by the phase-transfer catalyzed two-phase polycondensation of 2,2′-bibenzoyl chloride with various bisphenols and by the high-temperature solution polycondensation of biphenyl-2,2′-diol with aromatic dicarboxylic acid chlorides. All the polyarylates were amorphous and soluble in a variety of organic solvents including N,N-dimethylformamide, N-methyl–2-pyrrolidone, chloroform, m-cresol, and pyridine. Transparent and flexible films of these polymers could be cast from the chloroform solutions. These polyarylates had glass transition temperatures in the range of 120–250°C and began to lose weight at around 380°C in air. © 1992 John Wiley & Sons, Inc.  相似文献   

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Three novel nonlinear optical polyarylate polymers were prepared containing one main-chain polymer (mPAR-chr1) and two side-chain polymers (sPAR-chr1, sPAR-chr2) with different kinds of chromophores. The obtained polymers were characterized and evaluated by UV-Vis, 1H NMR, DSC and TGA. All the polymers exhibited excellent thermal stability, film forming ability and good electro-optic (EO) activity. The relationship between EO coefficients (r 33) and the chromophore concentration of the three polymers had been also characterized and discussed. There were no obvious differences found in EO activity between main-chain and side-chain polyarylates with the same chromophore (chr1). Due to the stronger electron-withdrawing tricyanopyrroline acceptor and the steric effect of the large dendritic groups of chromophore 2 (chr2), polymer sPAR-chr2 showed the largest EO cofficients (64 pm V?1) in these new polymers.  相似文献   

7.
Self-protective polyesters were synthesized in two ways: by polymer analog transformations on polymers obtained and by introduction of inhibiting groups into the polymer during synthesis. It is shown that the Fries rearrangement takes place in the aromatic polyesters in the presence of the Friedel-Crafts catalysts and on ultraviolet irradiation as well. Thermogravimetric analysis of the rearranged polymers and investigations of the influence of the ultraviolet irradiation on their properties show that the rearrangement markedly increases the photochemical and thermal stability of the polymers. Photostabilization may also be accomplished by the introduction of inhibiting groups, such as hydroxyl, sulfur, or phosphorus into the polymer molecule.  相似文献   

8.
Copolycondensations of TPA, PhHQ, and several aromatic diacid and diol modifiers were examined for which kind of the modifiers incorporated is more effective to reduce the transition temperatures of the resulting copolyesters and how they affect the temperatures. The acid modifiers are more effective than the diol ones, significantly when they have substituents. As another type of modifier, HBA forming the ester bond of an AB structure different from the AABB structure of TPA/PhHQ polyester was also effective, and the lowering effect on the temperatures was varied by the mode of copolycondensations, being most remarkable when HBA was randomly introduced. The results obtained were discussed in terms of the disturbance and thereby weakening of the interchain dipole–dipole interaction between the carbonyl groups in the ester linkages due to the introduction of the diacid modifiers and of HBA having an ester bond of a different directionality. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 621–626, 1999  相似文献   

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A series of novel perfluorononenyloxy group containing polyarylates were synthesized by a high-temperature solution condensation of 5-(perfluorononenyloxy)-isophthaloyl chloride ( II ) with various aromatic diols in o-dichlorobenzene. All the polyarylates were amorphous and readily soluble in many organic solvents such as o-chlorophenol, o-dichlorobenzene, chloroform, and polar aprotic solvents at room temperature or on heating. Transparent, tough, and flexible films of these polymers could be cast from the o-chlorophenol solutions. The polymers having inherent viscosity of 0.61–1.63 dL/g were obtained in quantitative yields. These polymers were thermally quite stable. The glass transition temperatures of these polyarylates were in the range of 219–242°C by DSC and 224–251°C by DMA, and the 10% weight loss temperatures in nitrogen and air were above 415 and 397°C, respectively. Moreover, these polymers maintained good mechanical properties (G′ ∼ 108 Pa) up to 220°C and had lower moisture absorption than common polyarylates. The dielectric constants of these polymers ranged from 3.23 to 3.75. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 645–653, 1998  相似文献   

11.
Conclusions A new simple method was developed for the synthesis of tricyclohexyltin chloride from SnCl4 and dicyclohexylaluminum chloride. The latter was obtained by reacting diisobutylaluminum chloride with cyclohexene in the presence of the binary Cp2ZrCl2/Ti(OBu)4 catalyst and a catalytic amount of (i-C4H9)2AlH.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1171–1173, May, 1984.  相似文献   

12.
Aromatic polyphosphonates of high molecular weights were prepared from phenylphosphonic dichloride and bisphenols having rigid ring structures by the two-phase polycondensation in organic solvent–aqueous alkaline solution system with phase-transfer catalyst at 0°C or below. The effects of reaction solvent and catalyst on the inherent viscosities of the polymers formed are studied. The glass transition temperatures of the polyphosphonates with biphenyl, phenylindane, and diphenylfluorene units are 120, 124, and 188°C, respectively. These polymers are self-extinguishing and are readily soluble in solvents such as N,N-dimethylacetamide, pyridine, tetrahydrofuran, and chloroform. They began to lose weight above 300°C in air. Copolyphosphonates from combinations of bisphenols and phenylphosphonic dichloride are also prepared and characterized.  相似文献   

13.
The preparation of an air-sensitive 16-electron complex, Cp2NbCl, is described. Its main property is easy transformation to 18-electron mononuclear compounds. Cp2Nb(=O)Cl and Cp2Nb(CO)Cl are obtained in oxidation and carbon monoxide gas addition processes, respectively. The physical properties of these complexes are described.  相似文献   

14.
A new series of blue photoluminescent aromatic polyesters (polyarylates) were synthesized from 1-[N,N-di(4-carboxyphenyl)amino]naphthalene with various bisphenols by the diphenylchlorophosphate (DPCP) activated direct polycondensation in a medium of pyridine and lithium chloride. The synthesis, basic characterizations, photoluminescence and electrochemical properties of this series of novel polyarylates bearing pendent naphthylamine chromophores were investigated. All polymers not only had good solubility in many polar aprotic solvents and excellent thin-film-forming ability, but also exhibited high Tg values, good thermal stability and lower highest occupied molecular orbital (HOMO) level. Thus, these naphthylamine-containing polyarylates may be widely applied in P-LED as hole-transporting layer and blue light-emitting materials due to their proper HOMO level, excellent thermal stability and fluorescence quantum efficiency.  相似文献   

15.
New 1,4‐naphthyl and 2,6‐naphthyl‐containing polyarylates having inherent viscosities up to 1.28 dL/g were synthesized by the high‐temperature solution polycondensation from the acid chloride of 1,4‐bis(4‐carboxyphenoxy)naphthyl or 2,6‐bis(4‐carboxyphenoxy)naphthyl and various bisphenols. Most of the resulting polyarylates showed amorphous characteristics and were readily soluble in common organic solvents such as N,N‐dimethylacetamide (DMAc), N‐methyl‐2‐pyrrolidone (NMP), o‐chlorophenol, and chloroform. Transparent, flexible, and colorless films of these polymers could be cast from the DMAc solutions. Their cast films had tensile strengths ranging from 54.9 to 84.2 MPa, elongations at break from 5.3% to 19.0%, and initial modulus from 2.0 to 2.8 GPa. These polymers had glass transition temperatures in the range of 172–280°C and began to lose weight around 400°C, with 10% weight loss being recorded at about 450°C in air. Dynamic mechanical analysis (DMA) reveals that the polyarylates containing isopropylidene linkages have three transitions on the temperature scale between −100 and 300°C. However, only two transitions were observed in the other polyarylates without isoproylidene linkage. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 645–652, 1999  相似文献   

16.
Summary New complex salts of lanthanide chlorides with hexamethylenetramine of the general formulaLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA-hexamethylenetetramine N4(CH2)6;n=8, 10, 12] have been obtained. On the basis of IR IR spectra (4000-200cm–1) and Raman spectra (3000-300 cm–1), changes in the coordination sphere structure of the salts occurring in the course of thermal dehydration have been determined.
Darstellung und Untersuchung der Eigenschaften von Komplexsalzen der Lanthanidchloride mit Hexamethylentetramin
Zusammenfassung Neue Komplexsalze der Lanthanidchloride mit Hexamethylentetramin mit der allgemeinen FormelLnCl3·2HMTA·nH2O [Ln=La, Pr, Nd, Sm, Dy, Er;HMTA — Hexamethylentetramin N4(CH2)6;n=8, 10, 12] wurden dargestellt. Die Änderungen in der Struktur der Koordinationssphäre während der thermischen Dehydration der Salze wurden mittels Infrarot-(4 000–200 cm–1) und Ramanspektroskopie (3 000–300 cm) bestimmt.
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17.
Organocuprate reagents were used for introducing bornane (1,7,7-trimethylbicyclo[2.2.1]heptane) moiety into the carbon skeleton of α,β-unsaturated carbonyl compounds. Prospects for use of the products obtained as fragrant substances were assessed.  相似文献   

18.
A series of fluorinated aromatic polyethers was synthesized via aromatic nucleophilic substitution of highly fluorinated aromatics (1,2,4,5-tetrafluorobenzene, hexafluorobenzene, and decafluorobiphenyl) with bisphenol AF or bisphenol A. Polymerization with 1,2,4,5-tetrafluorobenzene was not observed, and polymerization of hexafluorobenzene with bisphenol proceeded only if the potassium carbonate–bisphenol ratio was carefully controlled. The polymer condensed from decafluorobiphenyl and bisphenol AF was prepared in 77% yield with an inherent viscosity of 1.01 dL/g. The polymer prepared from the condensation of decafluorobiphenyl with bisphenol A was obtained in 48% yield with an inherent viscosity of 0.28 dL/g. These polymers were very soluble in common organic solvents, formed clear, colorless films, and were thermally stable (> 450°C by TGA). The fully fluorinated polymer exhibited low water uptake (0.3%) and dielectric constant (2.17). © 1992 John Wiley & Sons, Inc.  相似文献   

19.
A low temperature solution condensation method with pyridine as acceptor-catalytic reagent was applied to the synthesis of polyarylates from carbazole and bisphenol A/phenolphthalein. The polyarylates were classified with respect to their structure, thermal stability, and dielectric behavior.  相似文献   

20.
A new series of 16 aramids and 16 polyarylates having perfluoro-substituents on the benzene ring was prepared by a low temperature solution or an interfacial polycondensation. The effects of fluorine substituents on the structure and properties of polymers were examined. Fluorinated aramids exhibited higher crystallinity, while fluorinated polyarylates show lower crystallinity. The melting point (Tm) of aramids decreased with fluorine substitution, whereas Tm of polyarylates from fluorinated aromatic diols was higher than that of those from unfluorinated ones. The temperature of 10% weight loss and the residue at 900°C decreased with fluorine substitution except for the aramids from fluorinated diamines. Solubility and contact angle also increased with fluorine substitution. Some polyarylates were found to exhibit an optical anisotropy.  相似文献   

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