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  • 1
    Electronic Resource
    Electronic Resource
    A simplified wittig synthesis using polyacrylates with a terminal triphenylphosphonium group and polymerization of the macromonomers (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 743-748 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: In the presence of zinc halide, triphenylphosphine and chlorotrimethylsilane can be used directly to initiate group transfer polymerization of acrylate monomers. The resulting polymers with terminal triphenylphosphonium groups can be converted to the corresponding vinyl-macromonomers by means of the Wittig reaction. We found that the vinyl-macromonomers can be smoothly prepared with very good yields from the macromolecular phosphonium salts and aqueous formaldehyde in tetrahydrofuran/potassium hydroxide applying the phase transfer catalysed Wittig synthesis. The macromonomers were polymerized and copolymerized with styrene in butanone.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930320
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  • 2
    Electronic Resource
    Electronic Resource
    Chemical ionization mass spectrometry of benzoyl peroxide: A radical aromatic substitution resulting in biphenylcarboxylic acid in the gas phase (1993)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 28 (1993), S. 1435-1439 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A radical aromatic substitution resulting in biphenylcarboxylic acid is inferred for the decomposition of benzoyl peroxide from the chemical ionization and collision-induced dissociation mass spectra. The thermolysis of benzoyl peroxide gives rise to a benzoyloxy radical, which undergoes rapid decarboxylation and hydrogen abstraction leading to phenyl radical and benzoic acid, respectively. Attack of the resulting phenyl radical on the benzoic acid results in biphenylcarboxylic acid. On the other hand, the phenyl radical abstracts a hydrogen atom to yield benzene, which is then subjected to the attack of a benzoyloxy radical, affording phenyl benzoate. This substitution reaction rather than the recombination of benzoyloxy and phenyl radicals is found to be responsible for the formation of phenyl benzoate under the present conditions.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210281213
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  • 3
    Electronic Resource
    Electronic Resource
    New initiators for group transfer polymerization. Triphenylphosphonium-containing ketene silyl acetals (1989)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 190 (1989), S. 3061-3066 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: New initiators for group transfer polymerization (GTP), triphenylphosphonium-containing ketene silyl acetals, were synthesized by addition of triphenylphosphine and chlorotrimethylsilane to methyl acrylate or methyl methacrylate, respectively, giving 3-methyoxy-3-trimethylsiloxy-2-propenyltriphenylphosphonium chloride (4a) and its 2-methyl substituted derivative (4b), together with their corresponding oligomers (8). These phosphonium salts initiate GTP of ethyl acrylate using zinc halides as catalysts. The resulting polymers, containing a terminal triphenylphosphonium group, show a small polydispersity. In the presence of zinc halides, triphenylphosphine and chlorotrimethylsilane can be used directly to initiate GTP of acrylates and methacrylates. In this case triphenylphosphonium terminated polymers with a larger polydispersity are obtained.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1989.021901203
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  • 4
    Electronic Resource
    Electronic Resource
    Copolymerization of ε-caprolactone and morpholine-2,5-dione derivatives (1992)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 193 (1992), S. 1927-1942 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Novel biodegradable poly(ester-amide)s were prepared by ring-opening copolymerization of ε-caprolactone and 3- and/or 6-alkyl-substituted morpholine-2,5-dione derivatives. The copolymerizations were carried out in the bulk using stannous octoate as an initiator. Molecular weights of the copolymers ranged from 1,0 · 104 to 8,3 · 104 and decreased with increasing mole fractions of morpholine-2,5-dione derivatives in the feed. 13C NMR sequence analysis indicated that the copolymers had a random distribution of ε-oxycaproyl and depsipeptide units, which resulted from the occurrence of transesterification reactions during copolymerization. The results of the DSC measurements and 13C NMR sequence analysis showed a close relationship between the crystallinity and average length of ε-oxycaproyl blocks. Copolymers with a mole fraction of depsipeptide units smaller than 0,20 were semi-crystalline, whereas incorporation of larger amounts of depsipeptide units resulted in amorphous copolymers. The melting point depression as a function of the molar composition of the semi-crystalline copolymers was in good agreement with the melting point depression predicted by the Baur equation, which indicated the rejection of depsipeptide units from crystals consisting of ε-oxycaproyl units.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1992.021930813
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  • 5
    Electronic Resource
    Electronic Resource
    Electrochemical detection of mercury adsorbed from flowing gas samples on porous carbon electrodes (1997)
    Weinheim : Wiley-Blackwell
    Electroanalysis 9 (1997), S. 1201-1204 
    Details
    ISSN: 1040-0397
    Keywords: Mercury ; Coal ; Combustion gases ; Vitreous carbon foam ; Anodic stripping voltammetry ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The adsorption of mercury from flowing gas streams onto reticulated vitreous carbon (RVC) is combined with postadsorption stripping voltammetric determination. This novel analytical method achieves gas stream detection limits of 1.1 μg/m3 for unmodified RVC electrodes at 52°C and 1.8 μg/m3 for modified RVC electrodes at 25°C. Due to the unique features of this detection technique, it is possible and feasible that it could be applied for mercury analysis in coal fired power plant plumes and waste incinerator stacks.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/elan.1140091515
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