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  • 11
    Electronic Resource
    Electronic Resource
    The infrared absorption characteristics of poly(methyl methacrylate) doped with luminescent materials (1987)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 38 (1987), S. 443-446 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Infrarotspektren von Poly(methylmethacrylat)-Probenn die mit verschiedenen lumineszierenden Substanzen dotiert wurden, weisen außer beim β-Naphthol keine wesentlichen Änderungen der Lage und Intensität der Absorptionsbanden auf. Daher wird angenommen, daß zwischen den meisten Dotierungsmitteln und PMMA keine Wechselwirkung besteht, während beim β-Naphthol zwischen benachbarten Molekülen in der Polymermatrix Wasserstoffbindungen auftreten.
    Notes: The infrared spectra of poly(methyl methacrylate) samples doped with different luminescent materials show no drastic changes in the position and intensity of the absorption bands, except in case of β-naphthol. From this it is supposed that there is no interaction between the dopant and PMMA with most of the investigated materials, while with β-naphthol hydrogen bonding between adjacent molecules in the polymer matrix is observed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1987.010380708
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  • 12
    Electronic Resource
    Electronic Resource
    Physical and spectroscopic studies on methyl methacrylate-chromium acrylate bulk copolymers (1988)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 39 (1988), S. 399-403 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Durch Substanzcopolymerisation von Methylmethacrylat und Chromacrylat wurden neue halbleitende Copolymere erhalten. Das chemische Reaktionsschema wird diskutiert. Dichte und Harte der Proben nehmen mit steigendem Chromgehalt ab. Im Infrarotspektrum wurde eine Verbreiterung der Carbonylbande bei 1 710 cm-1 beobachtet, was auf eine mogliche Koordination der C=O-Gruppe mit Chromionen hinweist. Die elektrische Leitfahigkeit der Proben nimmt mit steigendem Chromacrylatgehalt zu. Der Einfluß einer γ-Bestrahlung auf die elektrische Leitfahigkeit der Copolymere wurde untersucht.
    Notes: New semiconducting copolymers were prepared by bulk copolymerization of methyl methacrylate with chromium acrylate. The pattern of the chemical reactions is discussed. The density and hardness of the samples decrease with increase of the chromium content. I n the infrared spectrum broadening of the carbonyl band a t 1710 cm-l is observed, which indicates the possibility of coordination of the C=O group with the chromium ion. The electrical conductivity of the samples increases with increase of chromium acrylate content. The effect of y-irradiation on the electrical conductivity of the copolymers was studied.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1988.010390718
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  • 13
    Electronic Resource
    Electronic Resource
    Infrared absorption characteristics and electrical conduction of methyl methacrylate-lithium acrylate copolymers (1988)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 39 (1988), S. 715-719 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Durch Substanzcopolymerisation von Methylmethacrylat und Lithiumacrylat mit Benzoylperoxid wurden halbleitende Copolymere synthetisiert. Ein Schema der chemischen Reaktionen wird vorgeschlagen. Die erhaltenen Proben sind statistische Copolymere. Die Infrarotspektren wurden gesmessen und im Hinblick auf die Struktur der Copolymere analysiert. Die gemessenen Werte der elektrischen Leitfähigkeit und der Einfluß von Gammabestrahlung auf die elektrische Leitfähigkeit der Copolymere werden diskutiert.
    Notes: Semiconducting copolymer samples were prepared by bulk copolymerization of methyl methacrylate with lithium acrylate using benzoyl peroxide as initiator. The pattern of the chemical reaction is discussed. The obtained samples were found to be random copolymers. Infrared absorption spectra were measured and analysed according to the copolymer structures. The data of electrical conductivity and the effect of gamma radiation on the electrical conductivity of the copolymer samples are discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1988.010391213
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  • 14
    Electronic Resource
    Electronic Resource
    Study of the emission spectra of poly(methyl methacrylate) films doped with luminescent materials (1989)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 40 (1989), S. 572-575 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Emissionsspektren von reinen und dotierten Poly(methylmethacrylat)-Filmen wurden registriert und im Hinblick auf die Verwendung der Filme als Lumineszenz-Solarenergie-Konzentratoren diskutiert. Als Dotierungssubstanzen wurden polyaromatische Kohlenwasserstoffe und einige Farbstoffe eingesetzt. Die meisten emittierten Banden erscheinen im Bereich 700 bis 400 nm, wenn die dotierten PMMA-Filme mit UV-Licht angeregt werden.
    Notes: The emission spectra of pure and doped poly(methyl methacrylate) films are recorded and discussed with respect of using the films as luminescence solar concentrators. The doping materials are polyaromatic hydrocarbons and some dyes. Most of the emitted bands appear in the region 700 to 400 nm when the doped PMMA films are excited with UV radiation.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1989.010400905
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  • 15
    Electronic Resource
    Electronic Resource
    Characterization of resins prepared by polycondensation of Egyption bagasse pith and bisphenol A. Part II. Elemental analysis and thin layer chromatographyPart I: Acta Polymerica 40 (1989) 667. (1990)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 41 (1990), S. 63-68 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Durch Polykondensation von Bisphenol A mit Verbindungen, die bei der Säurehydrolyse von Bagassemark entstehen, z. B. Glucose, Xylose und Furfural, wurden verschiedene Harze hergestellt. Weiterhin wurden Polykondensations produkte von Bisphenol A mit Bestandteilen des Bagassemarks, wie reines Sodalignin, Holocellulose und resistente Cellulose, erzeugt. Die optimalen Bedingungen für die Trennung dieser Polykondensate durch Dünnschichtchromato graphie wurden ermittelt.
    Notes: Different resins were prepared by polycondensation of bisphenol A with compounds which may be produced during the acid hydrolysis of bagasse pith, e.g., glucose, xylose, and furfural. Further bisphenol A was condensed with constituents of bagasse pith, namely, pure soda lignin, holocellulose and resistant cellulose. The optimum conditions for thin layer chromatographic separation of these polycondensates were determined.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1990.010410116
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  • 16
    Electronic Resource
    Electronic Resource
    Average molecular weights in heterogeneous polymerization of methyl methacrylate (1987)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 38 (1987), S. 167-169 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die mittleren relativen Molekülmassen von Poly(methlmethacrylaten), die durch mit Natriumbisulfit initiierte heterogene Polymerisation von Methylmethacrylat erhalten wurden, folgen den gleichen Gesetzmäßigkeiten wie bei der homogenen Polymerisation. Die in der Monomer- und Wasserphase sowie in der Grenzfläche gebildeten Polymere wurden hinsichtlich ihrer Polydispersität mittels Dünnschichtchromatographie untersucht.
    Notes: The average molecular weights of poly(methyl methacrylate)s obtained in heterogeneous polymerization of methyl methacrylate using sodium bisulfite as initiator were found to obey the same laws applied in homogeneous polymerization. The poly(methyl methacrylate)s formed in the monomer and water phases and the polymer formed at the interphase were investigated by thin layer chromatography with respect of their polydispersities.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1987.010380303
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  • 17
    Electronic Resource
    Electronic Resource
    Preparation and characterization of moulded shapes from Egyptian corncobs-bisphenol polycondensate resins and aluminium powder (1991)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 42 (1991), S. 670-674 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Aus mit Aluminiumpulver gefüllten Polykondensaten von ägyptischem Maiskolbenpulver und Bisphenol wurden verschiedene Formkörper hergestellt. Die Harze wurden mit Phenolformaldehyd, Naphthalenformaldehyd und Anthrazenformaldehyd modifiziert. Die Gleichstromleitfähigkeit der Proben steigt mit zunehmender Temperatur und höherem Aluminiumgehalt an. Alle Proben weisen Halbleitereigenschaften auf.
    Notes: Different types of moulded shapes were prepared from Egyptian corncobs-bisphenol polycondensate resins and aluminium powder. Modifications of the produced resin with phenol-formaldehyde, naphthalene-formaldehyde, and anthracene-formaldehyde, were performed. The electrical conductivity of the samples increases with the increase of temperature and aluminium concent. All samples reveal semiconducting behaviour.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1991.010421214
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  • 18
    Electronic Resource
    Electronic Resource
    Characterization of resins prepared by polycondensation of egyptian bagasse pith and bisphenol A. Part I. Physicochemical properties of the moulded shapes (1989)
    Weinheim : Wiley-Blackwell
    Acta Polymerica 40 (1989), S. 667-672 
    Details
    ISSN: 0323-7648
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die optimalen Bedingungen für die Synthese von linearen, löslichen und leicht verpreßbaren Kondensationsprodukten aus ägyptischem Bagassemark mit Bisphenol A als Kondensationsreagens wurden ermittelt. Zur Charakterisierung der erhaltenen Produkte wurde die Dünnschichtchromatographie eingesetzt. Die erhaltenen Kondensationsharze wurden mit Phenolformaldehyd, Anthracenformaldehyd und Naphthalenformaldehyd behandelt, um unterschiedliche Arten von Preßlingen herzustellen, die sich als mechanisch härter und chemisch stabiler erwiesen, als Preßlinge aus einem Phenolformaldehyd-Harz vom Novolac-Typ.
    Notes: Optimum conditions have been established for the synthesis of linear, soluble, and easily mouldable condensation products from Egyptian bagasse pith using bisphenol A as the condensation agent. Thin layer chromatographic technique was used for characterizing the products. The obtained condensate resins were treated with phenol formaldehyde, anthracene formaldehyde, and naphthalene formaldehyde to get different types of moulded products, which were found to be mechanically harder and chemically more stable than those of a phenol formaldehyde resin of novolac type.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/actp.1989.010401013
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  • 19
    Electronic Resource
    Electronic Resource
    Characterization of some poly(methyl methacrylate)s prepared by emulsifier-free emulsion polymerization in presence of some organic ligands and their nickel complexes (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 37 (1989), S. 65-75 
    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: The aqueous polymerization of methyl methacrylate (MMA) was studied using sodium bisulfite as initiator in absence and presence of tetraoxalyl urea (TOU), tetraoxalyl thiourea (TOthioU) and tetraoxalyl paraphenylene diamine (TOp-phD). The effect of their nickel complexes on the polymerization rate has also been studied. Ligands with free carboxyl groups have a retarding effect on the polymerization reaction, while their nickel complexes have a catalytic effect. The polymers obtained in presence of nickel complexes were found to have wider molecular weight distribution than those obtained in their absence; this was deduced by thin layer chromatographic analysis in a binary mixture (benzene/methanol). The apparent energy of activation was found to be 5.83 × 104 J/mol, 1.87 × 104 J/mol, 2.11 × 104 J/mol, and 3.95 × 104 J/mol in absence and in presence of 0.5 g of Ni complex of TOp-phD, TOthioU and TOU, respectively.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1989.070370106
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  • 20
    Electronic Resource
    Electronic Resource
    Characterization of some poly(methyl methacrylate) prepared by emulsion polymerization in presence of egyptian delta titano magnetite ore (EDTMO) (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 3677-3686 
    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: The emulsion polymerization of methyl methacrylate was studied in water using potassium persulphate as initiator and dedocyl-benzene sodium sulphonate as emulsifying agent at 85°C. The effect of Egyptian delta titano magnetite ore (EDTMO) upon the activation energy and on the mean average molecular weights of the obtained polymers was studied. It was found that the viscosity average molecular weights increase with decrease of reaction temperature and initiator concentration but increase with increase of monomer concentration in the reaction medium. Some of the polymer samples prepared in absence and in presence of some (EDTMO) were separated on tlc plates according to molecular weight in binary mixture, benzene:methanol (1:1.4 by volume) at 30°C. The tlc techniques were performed to give an idea about the molecular weight distribution of the polymer samples obtained.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070291204
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