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  • 1
    Online Resource
    Online Resource
    Berlin [u.a.] : Springer
    Part of " Advances in polymer science"
    Keywords: Biochemistry ; Polymers
    Type of Medium: Online Resource
    Pages: 1 Online-Ressource
    ISBN: 9783540468295
    Series Statement: Advances in polymer science 206
    DDC: 547.7
    RVK:
    Language: English
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  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Macromolecules 28 (1995), S. 1750-1753 
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Radical acrylamide telomerization was carried out with three fluorinated telogens, C6F13C2H4I, C6F13I, and C6F13-C2H4SH with AIBN as initiator. Transfer constants were determined to be 40 × 10-4, 550 × 10-4, and 6500 × 10-4, respectively. Reactions were carried out in butyronitrile, a solvent which also transfers to the growing chain. In the telomerization, the intervention of the solvent, whose transfer constant was also determined, is evaluated quantitatively. Thus the formation of side products, which may reach proportions on the order of 50% compared with the telomer expected, can be explained.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: telechelic oligomers ; halogenated telomers ; monodispersed α,ω-diols ; redox telomerization of allyl acetate ; α,ω-di(trichloromethyled) end grouped telomers ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The redox bistelomerization of allyl acetate with telogens which exhibit α, ω-di(trichloromethyled) end groups catalyzed by copper, iron salts, or a ruthenium complex led to monoadducts and telechelic oligomers. These diacetates were quantitatively changed into diols. Such compounds have been characterized by both 1H- and 13C-NMR. A reactivity series has been determined and shows that both end groups must be activated to obtain the expected telechelic products in satisfactory yields.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: ozonization ; grafting ; kinetics ; radical polymerization ; EVAg-styrene ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymers can be ozonized with an ozone/oxygen mixture to create peroxides and hydroperoxides on the polymer chain. These heat-sensitive functional groups can be used to initiate radical polymerization of vinyl monomers and give graft copolymers. The properties of these copolymers are well described in literature; however, we notice that available data concerning decomposition rate constants are inconsistent. Decomposition rate measurements, time of assay of free radicals and stability of the ozonized polymers do not give the same results. In this work, we studied the kinetics of the styrene polymerization initiated by an ozonized ethylene vinyl acetate copolymer. Consequently, the f·kd product can be calculated (f is the efficiency and kd the decomposition rate constant). The ozonized copolymer is not similar to usual radical initiators. The initial viscosity of the solution has an important effect on the calculation of the kinetic values. Activation energy and Arrhenius coefficient are different than the one obtained for the usual initiators. © 1994 John Wiley & Sons, Inc.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: fluorinated macrodiols ; radical telomerization ; surface properties hydroxyl terminated polybutadiene ; fluorinated thiol ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The radical grafting of CnF2n +1 CH2CH2SH (n = 6,8) onto the double bonds of hydroxyl-terminated liquid polybutadienes (HTPBD) was studied. Various methods for investigating the amount of grafting (titration of residual thiol and fluorine analysis) were used and compared. The nature and the amount of the initiator, the quantity of thiol, the temperature and the time of the reaction. the solvent, and the microstructure of HTPBD were optimized. The kinetic aspect showed that the thiol disappeared according to a first-norder law. A method using up to 100% of grafting fluorinated mercaptan was described and standards were set up with fluorine contents of 5-59% to evaluate the physicochemical properties of these thioether group-containing polymers: solubility, refractive index, intrinsic and dynamic viscosities, and thermal characteristics (glass transition and decomposition temperatures). Finally, the surface properties of these standards showed improvements of surface energy as low as 9 mN m-1 for a totally saturated fluorinated HTPBD. © 1993 John Wiley & Sons, Inc.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: maleimide monomers ; pyrazolic cycles ; vinyl ethers ; alternating copolymers ; reactivity ratio ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of maleimides that have pyrazolic or bipyrazolic pendant groups is described. Their homopolymerization and their copolymerization with 2-chloroethyl vinyl ether (CEVE) is reported. The homopolymerizations of such maleimides were performed under various conditions and led to low molecular-weight polymers. However, alternating copolymers were obtained from CEVE as comonomers whatever the monomers feed compositions. A similar behavior was also observed for maleimides that do not exhibit any spacer, whereas for bulky vinyl ethers, random copolymers were produced. A comparison of the thermal behavior between these copolymers (glass transition temperatures, Tg, and decomposition temperatures) and other copolymers having different spacers between the nitrogenated cycles and the chain are related. Thus, an important decrease of Tg, was observed when C3H6CO2CH2 groups were used as the spacer instead of methylene groups. Moreover, the thermal weakness of these copolymers may come from the substituents of the vinyl ether and is discussed. © 1994 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The stereoselectivity of the addition step and the transfer step of the radical telomerization of methyl methacrylate with thiophenol has been studied by determining the structure and the amount of each isomer by 1H-NMR. We found, in this case, that the addition step gave preferentially a diad r and that the transfer step gave preferentially a diad m. On the other hand, the tacticity observed for higher telomers is preferentially syndiotactic, similar to that of the poly(methyl methacrylate) prepared by radical initiation. The propagation process for radical telomerization obeys, as for the radical polymerization, Bernoulli's statistics.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    ISSN: 0887-624X
    Keywords: styrenic monomers ; pyrazolic cycles ; modification of chloromethyl styrene ; acceptor-donor copolymerization ; thermal properties ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The synthesis of styrenic monomers that have pyrazolic or bipyrazolic pendant groups is described. Their homopolymerization and their copolymerization with maleic anhydride (MA) and N-(3-acetoxy propyl) maleimide is reported. The monomers were prepared from the Williamson reaction between 2-pyridine carbinol, hydroxy monopyrazole, hydroxy bipyrazole, and chloromethyl styrene. The homopolymerizations of such styrenic monomers were tried under different conditions, which led to low molecular weight polymers with a high polydispersity. However, alternating copolymers were obtained using maleic anhydride or N-(3-acetoxy propyl) maleimide as comonomers, as shown by 1H-NMR, elemental analysis, and reactivity ratios r1 and r2. Furthermore, the hydrolysis of the acetate function of different copolymers was performed quantitatively. Unlike the acetoxy copolymers, such products do not have any glass transition temperature. Thermogravimetric investigations have shown that these copolymers exhibit good thermostability. © 1994 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Macromolecular Chemistry and Physics 195 (1994), S. 129-137 
    ISSN: 1022-1352
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: A polymerizable methacrylic surfactant is synthetized from methacryloyl chloride and 11-bromoundecanol. The obtained cationic monomer is telomerized with a fluorinated thiol, and the transfer constant CT is calculated. This value is in the same range as transfer constants of classical methacrylic monomers. The obtained kp2/kT is low because of the long chain ester. Polymers were prepared in homogeneous solution with an average molecular weight of 25 000.
    Additional Material: 4 Tab.
    Type of Medium: Electronic Resource
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