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  • 1
    ISSN: 1436-2449
    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: Summary The effect of ZnCl2 addition on the reactivity ratios of the system acrylonitirle (AN)-N-2-Chlorophenylmaleimide (2CMI) has been investigated. It has been found that the addition of small amount of ZnCl2 doubles the reactivity of AN while drastically decreasing that of the 2CMI. The viscosity of the copolymers has been measured and was found to decrease with increasing the maleimide and the ZnCl2 concentrations.
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  • 2
    ISSN: 1436-2449
    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: Summary The title monomer has been prepared for the first time. It has been polymerized by a free radical mechanism in different solvents. Only oligomers were obtained so far. The dependence of the rate of polymerization on monomer and initiator concentrations has been measured and was found to follow the usual free radical scheme. The overall activation energy of polymerization has been measured in two solvents and was found to be 21.2 and 15.03 K.Cal/mol in tetrahydrofuran (THF) and N,N-dimethyl formamide (DMF) respectively. The prepared monomer has excellent chelating ability with different metal cations. The stability constant of the monomer with copper (II) ions has been measured in acetone as well as in dioxane. The complexes have no tendency for free radical polymerization.
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  • 3
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Copolymerisation von Acrylnitril mit zwei verschiedenen N-Arylmaleinsäre-amiden als auch mit N-3-Carboxyphenylmaleimid wurde in Dimethylformamid mit Azobisisobutyronitril als Initiator ausgeführt. Die Copolymerisationsparameter und die Q-e-Werte dieser Monomeren wurden berechnet. Die Charakterisierung der so hergestellten Copolymeren erfolgte durch Viskositätsmessungen und Thermoanalysen. Die durch Thermogravimetrie und Differentialthermoanalyse erhaltenen Werte zeigen eine Verbesserung des thermischen Verhaltens der untersuchten Copolymeren im Verbesserung des thermischen Verhaltens der untersuchten Copolymeren im Vergleich zum Poly(acrylnitril). Ein Mechanismus, der Oligomerisierung der die Rolle der Sauren Gruppen als such der Maleimideinheiten an der Oligomerisierung der Nitrilgruppen ver-deutlicht, wurde vorgeschlagen. Die hergestellten Copolymeren Zeigen eine sehr gute Affinität bezüglich basischer Farbstoffe und eine verbesserte Farbbeständigkeit gegenüber UV-Strahlung.
    Notes: Acrylonitrile was copolymerized with two N-arylmaleamic acids and with N-3-carboxyphenylmaleimide in dimethylformamide (DMF) using azobisisobutyronitrile as initiator. The reactivity ratios and the Q-e parameters of these monomers were estimated, and the resulting copolymers were characterized by viscosity measurements and thermal analysis. Thermogravimetry and differential thermal analysis data showed an improvement in the thermal behaviour of the investigated copolymers compared with that of poly(acrylonitrile). Mechanisms illustrating the role of both the acidic group and the maleimide ring in the nitrile oligomerization were proposed. The produced copolymers showed an excellent affinity towards basic dyes and better color fastness towards UV light.
    Additional Material: 5 Ill.
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  • 4
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Acrylnitril wurde sowohl mit drei N-Arylmaleimiden als auch mit N-Octadecylmaleimid in Dimethylformamid (DMF) mit Azobisisobutyronitril als Initiator copolymerisiert. Die Copolymerisationsparameter wurden nach Fineman-Ross und nach Kelen-Tüdős bestimmt und hieraus die Q- und e-Werte der Monomeren berechnet. Die hergestellten Copolymeren wurden durch Viskositätsmessungen und Thermoanalysen charakterisiert. Die Grenzviskosität der Polymeren sinkt mit steigendem Gehalt an Maleimideinheiten. Die durch Thermogravimetrie (TG) und Differential-Thermoanalyse (DTA) erhaltenen Werte zeigen eine bemerkenswerte Verbesserung des thermischen Verhaltens der untersuchten Copolymeren. Ein Mechanismus für die Beteiligung der Maleimideinheiten an der Oligomerisierung der Nitrilgruppen wurde vorgeschlagen. Die Untersuchung der Färbeeigenschaften aller Copolymeren mit Ausnahme derer, die Octadecylmaleimid enthalten, ergab sowohl eine gute Affinität bezüglich basischer Farbstoffe als auch eine recht gute Verbesserung der Farbbeständigkeit gegen UV-Strahlung.
    Notes: Acrylonitrile was copolymerized with three N-arylmaleimides as well as with N-octadecylmaleimide in dimethylformamide (DMF) using azobisisobutyronitrile (AIBN) as initiator. The monomer reactivity ratios were calculated by the Fineman-Ross and the Kelen-Tüdős methods from which the Q- and e-parameters of these monomers were evaluated. The prepared copolymers were characterized by viscosity measurements and thermal analysis. The intrinsic viscosity decreases by increasing the maleimide content in the copolymer. Thermogravimetry TG and differential thermal analysis (DTA) data showed a remarkable improvement in the thermal behaviour of the investigated copolymers. A mechanism for the participation of the maleimide units in the nitrile oligomerization was also proposed. The investigation of the dyeing properties of the copolymers with the exception of those containing octadecylmaleimide, showed good affinity towards basic dyes as well as an appreciable improvement in their colour fastness towards UV light.
    Additional Material: 4 Ill.
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  • 5
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Copolymerisation von Acrylnitril (AN) und Glycidylmethacrylat (GMA) in Tetrahydrofuran wurde untersucht. Die Reaktivitältsverhältnisse wurden bestimmt und das thermische Verhalten der Homo- und der Copolymeren wurde mit Hilfe der Differentialthermoanalyse (DTA) und der Thermogravimetrie (TG) untersucht. Es wurde gefunden, daß GMA beim Aufheizen die Nitriloligomerisationsreaktion initiiert. Die Anfärbbarkeit und die Bleichung in UV-Licht wurden ebenfalls untersucht. Verglichen mit Homopolyacrylnitril zeigen die Copolymeren bessere Affinität gegen basische Farbstoffe. Diese Affinität steigt mit zunehmendem GMA-Anteil im Copolymeren an.
    Notes: The copolymerization of acrylonitrile (AN) with glycidyl methacrylate (GMA) has been investigated in tetrahydrofuran (THF). The reactivity ratios were estimated and the thermal behaviour of the homo- as well as the copolymers, both in air, and under nitrogen atmosphere was investigated using differential thermal analysis (DTA) and thermogravimetry (TG) techniques. GMA was found to initiate the nitrile oligomerization reaction in the copolymers upon heating. The dyeing ability, as well as the colour fastness towards UV light have also been investigated. It was found that the copolymers showed better affinity towards basic dyes compared to homopolyacrylonitrile. This affinity increases with increasing the GMA content in the copolymer.
    Additional Material: 9 Ill.
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  • 6
    ISSN: 0887-624X
    Keywords: 4-vinylpyridine ; zinc ; complexes ; spontaneous ; copolymerization ; electron-rich ; monomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The spontaneous copolymerization of 4-vinylpyridine (4-VP) complexed with three different zinc salts (chloride, acetate, and triflate) with various electron-rich vinyl monomers (p-methoxystyrene, MeOSt; p-methylstyrene, MeSt; α-methylstyrene, α-MeSt; p-tert-butylstyrene, BuSt; styrene, St) was investigated in methanol at 75°C. Increasing the zinc salt concentration or the nucleophilicity of the electron-rich monomer increased the copolymer yields. All obtained copolymers are characterized by high molecular weight (105) and broad molecular weight distribution. Both 1H-NMR and elemental analyses confirmed the almost 1 : 1 copolymer structure. Changing the anion of the zinc salt does not have a considerable effect either on the copolymerization rate or on the molecular weight. The proposed mechanism exhibits the formation of a σ-bond between the β-carbons of the two donor-acceptor monomers. This creates the 1,4-tetramethylene biradical intermediate which can initiate the copolymerization reaction. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 2787-2792, 1997
    Additional Material: 2 Tab.
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  • 7
    ISSN: 0887-624X
    Keywords: polyaniline ; acylation ; alkylation ; solubility ; conductivity ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Various alkylating and acylating agents, with different electrophilicity, were allowed to react with polyaniline “emeraldine base” (Pan-EB) or its anion. Replacing the N-hydrogens of polyaniline by various acyl or benzyl groups strongly affected the solubility and the electrical conductivity of the polymer. Neutral Pan-EB was reacted with benzoyl chloride, p-t-butylbenzoyl chloride or pivaloyl chloride in N,N′-dimethylpropylene urea (DMPU) solutions. While the benzoyl and pivaloyl derivatives showed very poor solubility in common organic solvents, the p-t-butylbenzoyl derivative was readily soluble in THF, chloroform, DMSO, etc. As expected, these acyl derivatives showed diminished electrical conductivity relative to that of the parent Pan-EB. Benzyl chlorides did not react with neutral Pan-EB. Attempts to prepare solutions of the nitrogen anion of Pan-EB by reaction with sodium hydride in DMSO or DMPU led invariably to crosslinked insoluble material. This was ascribed to Michael addition of the formed nitrogen anions to the quinonimine moieties. However forming the nitrogen anion in presence of p-t-butylbenzyl chloride trapped it to form N-benzylated Pan-EB. This was a soluble high molecular weight, electrically conductive (4.3 × 10-1 S cm-1 as the hydrochloride) N-alkyl Pan-EB. Reacting Pan-EB with excess of both sodium hydride and benzyl chlorides led to film-forming per-benzylated Pan-leucoemeraldine reduced form. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 1673-1679, 1997
    Additional Material: 1 Ill.
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  • 8
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
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  • 9
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
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  • 10
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
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