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  • 1
    Electronic Resource
    Electronic Resource
    The infulence of aromatic diols on thermotropic Poly(ester-amide)s synthesized by direct polycondensation (1996)
    Springer
    Journal of polymer research 3 (1996), S. 89-95 
    Details
    ISSN: 1572-8935
    Keywords: Thermotropic ; Poly(ester-amide)s ; Direct polycondensation ; DPCP ; Nematic
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Thermotropic Poly(ester-amide)s containing triethyleneglycol bis(4-carboxyphenyl) ether (PEG3), o-Tolidine (OT) and various aromatic diols such as hydroquinone (HQ) and 4,4′-biphenol (BP) were synthesized by direct polycondensation with DPCP (diphenyl chlorophosphate) as direct condensation agent in the presence of pyridine and LiCl. The polymer structures were characterized by infrared spectroscopy and elemental analysis. The influence of structure, substituents and contents of various aromatic diols on the phase transitions were studied by Differential Scanning Calorimetry (DSC) and Polarized Optical Microscopy. These revealed that the structure and substituents of diols affected the mesophase while most of the synthesized polymers exhibit nematic mesophase. Addition of HQ decreased the melting temperature of the polymers, but, in contrast to others diols, did not affect thermal resistance.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01492899
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  • 2
    Electronic Resource
    Electronic Resource
    Crystallization behavior of block copolyarylates synthesized via two-step interfacial polycondensation (1989)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 190 (1989), S. 1413-1423 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: DSC, X-ray diffraction and solid-state 13C NMR were used to investigate the crystallization properties of block copolyarylates prepared via two-step interfacial polycondensation. The block copolyarylates obtained from 1,1,2,2-tetrachloroethane solution were found to have low crystallinity. This could be explained as the influence of amorphous blocks on the crystalline blocks. When the block copolyarylates were redissolved in dichloromethane, the annealed, cast films exhibited considerably higher crystallinity. It was concluded that the crystallization behavior of block copolyarylates is very much dependent on their sample history.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1989.021900621
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  • 3
    Electronic Resource
    Electronic Resource
    Transition kinetics of smectic liquid-crystalline polyesters (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 2477-2486 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Two smectic main-chain liquid-crystalline polyesters containing biphenyl as mesogen and spacers with 8 and 18 methylene carbon atoms were prepared, and their transition kinetics were investigated by means of differential scanning calorimetry (DSC). The isothermal liquid-crystallization was analyzed using the Avrami equation. The Avrami exponent n was found to be 2 to 4 indicating that the liquid-crystallization of these two smectic polyesters would be a process of two-to three-dimensional growth rather than of one-dimensional growth as for nematic liquid-crystalline polymers. The nonisothermal liquid-crystallization and crystallization were also analyzed by means of DSC. The crystallization from the smectic phase was found to be a very fast process and the supercooling of crystallization was small. Thus, the smectic phase might nucleate crystallization. The transition kinetics of these two smectic polyesters are considerably different from those of nematic liquid-crystalline polymers due to the different orders of the liquid-crystalline phases.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930930
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  • 4
    Electronic Resource
    Electronic Resource
    Polyimides, 1. Studies on the thermal curing of imide model compound with tricyclic structure by nuclear magnetic resonance and mass spectraRevised Manuscript of October 15, 1991. (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 1521-1535 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A model imide with a tricyclic structure was synthesized by reacting 3-phenyltricyclo[6.2.2.02,7]-2,11-dodecadiene-5,6 : 9,10-tetracarboxylic dianhydride with aniline. The thermogravimetry curve showed that it degraded at about 300°C, and its differential scanning calorimetry curve was found to be similar to that of its corresponding polyimides. The thermal curing of this model imide was studied in detail. A curing mechanism was proposed based on the analysis of the cured product using NMR and mass spectroscopy. The results show that the curing mechanism started with a reverse Diels-Alder reaction, forming an intermediate which either dehydrogenated or further decomposed into 1,1-diphenylethylene, and N-phenylsuccinimide. The 1,1-diphenylethylene and N-phenylsuccinimide would either polymerize or become hydrogenated to form 1,1-diphenylethane and N-phenylsuccinimide, respectively.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930628
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  • 5
    Electronic Resource
    Electronic Resource
    Polymides, 2Part 1: cf. ref.22. Curing characterization and thermally induced polymerization of polyimides based on reverse Diels-Alder reaction (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 1537-1550 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Polyimides were prepared by the condensation of 3-phenyltricyclo[6.2.2.02,7]-2,11-dodecadienne-5,6:9,10-tetracarboxylic dianhydride with diamines. Thermal curing of these polyimides was studied using thermogravimetry, infrared spectroscopy, nuclear magnetic resonance spectroscopy, mass spectroscopy and elemental analyses. The results were compared with those of a model imide compound and a neat dimaleimide. It is proposed that the thermal curing mechanism is controlled by a reverse Diels-Alder reaction, a three-dimensional polymer network being formed following the degradation of the polymer. Based on these studies, a three-dimensional structure is proposed if the curing temperature was over 330°C. The weight loss of isothermal thermogravimetry studies was tentatively used to determine the composition of the crosslinked structure and elemental analyses confirmed the results.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930629
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  • 6
    Electronic Resource
    Electronic Resource
    Solution and rheological properties of poly(m-phenyleneisophthalamide) in dimethylacetamide/LiCl (1979)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 23 (1979), S. 2155-2168 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: An experimental study of the solution properties of poly(m-phenyleneisophthalamide) (MPD-I) in dimethylacetamide (DMA)/LiCl solutions is presented. Differential refractometry, light scattering photometry, dilute and concentrated solution viscometry, and normal stress experiments are reported and interpreted. This polymer in the concentration range investigated does not exhibit mesophase behavior in contrast to its para-linked analog. Generally, it behaves as a flexible polymer molecule; however, its capacity to become a polyelectrolyte strongly influences its behavior in the presence of LiCl. MPD-I is self-associated when dissolved in pure DMA but dissociates in DMA/LiCl solvent systems. The Zimm plots of MPD-I in DMA/LiCl solutions show distortion, probably due to polymer-salt interactions.
    Additional Material: 13 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1979.070230726
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  • 7
    Electronic Resource
    Electronic Resource
    Liquid-rubber-modified epoxy adhesives cured with dicyandiamide. II. - Morphology and adhesion strengths (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 33 (1987), S. 2267-2267 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070330637
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  • 8
    Electronic Resource
    Electronic Resource
    Polyarylates. II. The molecular weight distribution measured by GPC (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 1709-1712 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250623
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  • 9
    Electronic Resource
    Electronic Resource
    Polyarylates (I): Investigation of the interfacial polycondensation reaction by UV (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 1505-1515 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The interfacial polycondensation of bisphenol A with isophthaloyl chloride and terephthaloyl chloride in dichloromethane with triethylbenzylammonium chloride as the catalyst was described. A well-defined two-phase system had been observed, so the concentration of bisphenolate in the aqueous phase could be determined by UV spectrometer. The conversion was found to increase rapidly with reaction time, but the rate of increase in molecular weight was slow. At the initial stage with conversion up to 95%, the reaction proceeded similarly to that of solution polycon-densation because the synthesized polyarylate could be dissolved in dichloromethane, and a polymer with a low molecular weight resulted. At the final stage of the reaction, the molecular weight was increased to a very high value due to the local concentration effect. The mole ratio of bisphenol A to diacid chlorides was found to affect the molecular weight very much. In the case of a mole ratio less than 1, the reaction remained in the initial stage mostly, and the molecular weight was low. However, for a mole ratio greater than 1, polyarylate with a very high molecular weight could be obtained because the local concentration effect was much more significant owing to the high concentration of bisphenolate that remained in the aqueous phase at the final stage.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250605
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  • 10
    Electronic Resource
    Electronic Resource
    Polyarylates. III. Kinetic studies of interfacial polycondensation (1987)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 25 (1987), S. 2195-2206 
    Details
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of interfacial polycondensation of bisphenol A with isophthaloyl chloride and terephthaloyl chloride in dichloromethane with triethylbenzylammonium chloride (TEBAC) as the catalyst was investigated via measurements of bisphenolate concentration by UV. The reaction was found to be second order with respect to bisphenolate. The dependence of the rate constant on stirring speed, amount of TEBAC, and reaction temperature was studied. The rate constant was increased with an increase of stirring speed, quantity of TEBAC added, as well as the reaction temperature. The activation energy was found to be 7.7 kcal/mol at a stirring speed of 700 rpm in the presence of 0.160 of TEBAC. The role of TEBAC was found to be interesting. It did not alter the equilibrium (the partition coefficient remained the same in the presence of TEBAC), but it did enhance the transfer rate of bisphenolate.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pola.1987.080250816
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