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  • 1
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of the American Chemical Society 106 (1984), S. 4035-4036 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 9 (1969), S. 136-150 
    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 binäre Copolymerisation der Monomeren 1,3-Dioxolan (DOL), Styrol (St) und 3,3-Bischlormethyl-oxacyclobutan (BCMO) sowie die Terpolymerisation dieser Monomeren wurden unter Venvendung von Et3OBF4 als Initiator untersucht. Ein statistisches Copolymerisat aus DOL und St mit einem Molekulargewicht von 3 · 105 wurde hergestellt. Durch „Living-Polymerisation“ von DOL mit diesem Initiator wurde ein Blockcopolymeres (I) durch Zweistufencopolymerisation hergestellt, das aus einem DOL-Homopolymerblock und einem DOL-St-Copolymer-block besteht, wobei St zu einer Losung von „Living-DOL“ hinzugefugt wurde: (I)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL} \ {\rm homopolymer}} \right) \hbox{--} \left( {{\rm DOL-St} \ {\rm copolymer}} \right).$$\end{document}Aufähnliche Weise wurde das Blockcopolymere (II) aus DOL und BCMO hergestellt (II)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL} \ {\rm homopolymer}} \right) \hbox{--} \left( {{\rm DOL-BCMO} \ {\rm copolymer}} \right).$$\end{document}Die Terpolymerisation von DOL, St und BCMO ergab eine teilweise in heißem Benzol unlösliche harzige Substanz. Zumindest der unlosliche Teil wurde durch Elementaranalyse und seine Loslichkeit als Terpolymeres erkannt. Die Zweischritt-Terpolymerisation durch Zugabe von BCMO zu einer Losung von „Living“-DOL-St-Copolymerem ergab ein in Benzol losliches Produkt, von dem angenommen wird, daß es ein Blockcopolymeres (III) aus einem DOL-St-Copolymerblock und einem DOL-St-BCMO-Terpolymerblock ist: (III)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL-St} \ {\rm copolymer}} \right) \hbox{--} \left( {{\rm DOL-St-BCMO} \ {\rm terpolymer}} \right).$$\end{document}Aus der erfolgreichen Herstellung eines Terpolymers aus DOL, St und BCMO wird geschlossen, daD die beiden letzteren Monomeren, die miteinander nicht copolymerisieren, in eine Copolymerkette eingebaut werden konnen auf Grund einer Vermittlerrolle des DOL-Monomeren.
    Notes: Copolymerizations of combinations of 1.3-dioxolane (DOL), styrene (St) and 3.3-bis(chloromethyl) oxacyclobutane (BCMO), and terpolymerization of these monomers were investigated with the use of Et3OBF4 as an initiator. A random copolymer of DOL and St with molecular weight as high as 3 × 105 was prepared. By utilizing a “living” nature of the polymerization of DOL by this initiator, a block copolymer (I) consisting of a DOL homopolymer block and a DOL-St copolymer block was synthesized by two step copolymerization in which St monomer was added to a solution of “living” DOL polymer (I)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL} \ {\rm homopolymer}} \right) \hbox{--} \left( {{\rm DOL-St} \ {\rm copolymer}} \right).$$\end{document}In a similar way, a block copolymer (II) was also prepared from DOL and BCMO: (II)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL} \ {\rm homopolymer}} \right) \hbox{--} \left( {{\rm DOL-BCMO} \ {\rm copolymer}} \right).$$\end{document}Terpolymerization of DOL, St and BCMO gave a resinous material, partly insoluble in hot benzene. At least the insoluble part was confirmed to be a terpolymer by elemental analysis and solubility tests. Two step terpolymerization by adding BCMO monomer into a solution of “living” DOL-St copolymer yielded a benzene soluble product which was supposed to be a block copolymer (III) composed of a DOL-St copolymer block and a DOL-St-BCMO terpolymer block: (III)\documentclass{article}\pagestyle{empty}\begin{document}$$\left( {{\rm DOL-St} \ {\rm copolymer}} \right) \hbox{--} \left( {{\rm DOL-St-BCMO} \ {\rm terpolymer}} \right).$$\end{document}It is concluded by the successful preparation of terpolymers of DOL, St and BCMO that the latter two monomers which do not copolymerize with each other can be incorporated into a copolymer chain through the intermediary of DOL monomer.
    Additional Material: 10 Tab.
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  • 4
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 1401-1409 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerization of methylenedioxolanes, such as 4-methylene-1,3-dioxolane (I) and 2,2-dimethyl-4-methylene-1,3-dioxolane (II), with maleic anhydride (Manh) gives rise spontaneously to the alternating copolymers by the participation of charge-transfer (CT) complexes. The formation of CT complexes I-Manh and II-Manh was ascertained by UV and NMR spectroscopies. The equilibrium constants (K) could not be determined but were assumed to be small (K ≪ 1). For comparison with these systems an investigation of I-dimethyl maleate (DMM) and II-DMM systems was carried out to estimate K values 0.115 and 0.157 L/mol, respectively. To clarify the copolymerization mechanism I-Manh-acryronitrile was terpolymerized. Consequently it was concluded that the spontaneous copolymerization of I-Manh and II-Manh systems is effected by the CT complex monomer mechanism.
    Additional Material: 5 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Letters Edition 21 (1983), S. 171-176 
    ISSN: 0360-6384
    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
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  • 6
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2935-2942 
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The formation of charge-transfer (CT) complexes of unsaturated spiro ortho esters such as 2-methylene-1,4,6-trioxaspiro[4.4]nonane(I) and 2-methylene-1,4,6-trioxaspiro[4.6]undecane(II) with maleic acid derivatives such as maleic anhydride (Manh), dimethyl maleate (DMM), and N-ethyl maleimide (NEM) was ascertained by ultraviolet (UV) and nuclear magnetic resonance (NMR) spectroscopy. The stoichiometries of these complexes were estimated as 1:1. The determination of their equilibrium constants (K) was attempted by using the Hanna-Ashbough equation with NMR spectroscopy. Although K values for I-DMM and II-DMM were specified as 0.266 and 0.336 L/mol, respectively, those for the other systems could not be obtained but were assumed to be negligible small (K ≪ 1). Copolymerization of these systems which was carried out without an initiator determined that spontaneous copolymerization occurs in all cases but that the copolymerization rates of I-DMM and II-DMM systems are slow. The systems in which Manh or DMM was used as an acceptor monomer gave the alternating copolymers at various monomer to feed ratios. The terpolymerizaton of the I-Manh-DMM system established that DMM takes little part in giving the alternating copolymers I and Manh. Consequently, it was assumed that the reactivity of the CT complex monomer is dependent on the contribution of the dative structure to CT complex.
    Additional Material: 5 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 188 (1987), S. 2259-2265 
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The equilibrium polymerization of tetrahydrofuran was studied at relatively low initial monomer concentrations with 1-methyltetrahydrofurylium hexachloroantimonate as initiator. The equilibrium concentrations of monomer, [M]e, and initiator, [I]e, as well as the equilibrium number-average degree of polymerization, Pn, were determined by means of 1H NMR spectroscopy, and found to follow simplified relations, which were derived from Tobolsky's equations.
    Additional Material: 3 Ill.
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  • 8
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Der Mechanismus der Initiierungsreaktion bei der Polymerisation von cyclischen Äthern und von Laktonen mit Triäthyloxonium-, Acetyl- und Dioxolenium-Salzen wurde untersucht.Triäthyloxonium-Salze initiieren die Polymerisation cyclischer Äther über eine Umalkylierung. Mit cyclischen Estern tritt eine Reaktion sowohl am Äther- als auch am Carbonyl-Sauerstoff ein; die Polymerisation verläuft aber ausschließlich über eine Acyl-Spaltung.Bei der Polymerisation von THF mit Triäthyloxonium-Salzen ist die Geschwindigkeitskonstante der Wachstumsreaktion kp nahezu unabhängig vom Gegen-Anion. Acetyl-Kationen starten die THF-Polymerisation nur teilweise unter Ausbildung von gebundenen Oxonium-Ionen mit den Monomeren; Dioxolenium-Salze starten dagegen ausschließlich nach diesem Mechanismus.
    Notes: The mechanism of the initiation reaction for the polymerization of cyclic ethers and lactones by triethyloxonium-, acetyl- and dioxolenium-salts was studied.Triethyloxonium salts initiate the polymerization of cyclic ethers simply by the alkyl exchange reaction. Cyclic esters react with triethyloxonium salts at both ether and carbonyl oxygens but the polymerization proceeds by the acyl-oxygen fission. The kp value of the polymerization of THF by triethyloxonium salts is almost constant independent of gegenanion. Acetyl cation initiates the polymerization of THF partly by bonding mechanism, but dioxolenium salt initiates completely by bonding.
    Additional Material: 16 Ill.
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  • 9
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Die Startreaktion der kationischen Polymerisation von Tetrahydrofuran durch Acetylhexafluorantimonat und 2-Methyl-1.3-dioxolenium-perchlorat ist aufgrund der großen Stabilität der kationischen Salze langsamer als die Wachstumsreaktion. Durch die Zugabe von 4 Mol Epichlorohydrin oder 10 Mol Trimethylenoxid als Aktivator zu 1 Mol Initiator wird die Geschwindigkeit der Startreaktion derjenigen der Wachstumsreaktion vergleichbar; einige Male wurde eine Zunahme der Polymerisationsgeschwindigkeit beobachtet. Einige Aktivatoren blieben unverbraucht und verursachten in der Anfangsphase Kettenübertragung.
    Notes: The initiation reaction of the cationic polymerization of tetrahydrofuran by acetyl hexafluoroantimonate and 2-methyl-1.3-dioxolenium perchlorate is slower than the propagation reaction, due to the great stability of the cationic salts. Addition of 4 moles of epichlorohydrin or 10 moles of trimethylene oxide to 1 mole of the initiator as a promotor accelerated the initiation reaction comparable to the propagation reaction and several fold increase of the rate of polymerization was observed. Some promotors remain unconsumed at the initiation reaction and cause some chain transfer at the initial stage.
    Additional Material: 6 Ill.
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  • 10
    ISSN: 0449-2986
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
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