Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Reaction of water soluble polymers with oxidising agents: reaction of dextran with tetravalent cerium (1984)
    Springer
    Colloid & polymer science 262 (1984), S. 939-947 
    Details
    ISSN: 1435-1536
    Keywords: Spectrophotometry ; complex ; degradation ; viscometry ; transient-radical
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Dextran, an extracellular bacterial polysaccharide, was subjected to reaction with ceric ammonium nitrate in aqueous nitric acid at varying temperatures. The polymer has been found to be degraded due to the selective oxidative cleavage of vicinal glycol units present in the monosaccharide unit of each chain. The aldehyde groups produced upon cleavage at low temperature were found to undergo further oxidation to acids and formic acid with rise in temperature of the reaction. The course of the reaction has been followed by cerimetry and by spectrophotometrical measurements. The effect of the concentration of reacting components on the reaction has been studied and various kinetic aspects have been evaluated. Depending on the kinetic results, a plausible reaction mechanism for the oxidative degradation and the subsequent reactions have been suggested by the study of the changes of solution viscosity and initiation of graft copolymerization of vinyl monomers by Ce(IV)/dextran mixture. Various thermodynamic parameters have been evaluated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01490026
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Grafting of vinyl monomers onto nylon-6. 1. Graft copolymerization of acrylamide onto nylon-6 using trivalent manganese as initiator (1979)
    Weinheim : Wiley-Blackwell
    Angewandte Makromolekulare Chemie 80 (1979), S. 95-103 
    Details
    ISSN: 0003-3146
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The use of trivalent manganese to initiate graft-copolymerization of acrylamide onto nylon-6 has been investigated. The rate of grafting has been determined by varying monomer, manganese(III), temperature and solvent mixtures. The graft yield increases with increasing monomer concentration up to 0.8 M and with further increase of monomer concentration the graft yield decreases. The percentage of grafting increases with managanese (III) ion concentration up to 5.25 × 10-3 M and thereafter it decreases. The rate of reaction depends on temperature. Among the solvent composition studied, a water/solvent mixture containing 25% of the solvent seems to constitute the most favourable medium for grafting and with further increase of solvent composition, the graft yield decreases.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/apmc.1979.050800106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Polymerization of methyl methacrylate initiated by Mn(III)-glycerol redox system (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 1-7 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of thermal polymerization of methyl methacrylate initiated by the redox system Mn(III)-glycerol was studied in aqueous sulfuric acid in the temperature range of 30-40°C, and the rates of polymerization, Rp, and Mn3+ disappearance, etc., were measured. The effect of certain water-miscible organic solvents and certain cationic and anionic surfactants on the rates of polymerization has been investigated. A mechanism involving the formation of a complex between Mn3+ and glycerol whose decomposition yields the initiating free radical with the polymerization being terminated by the metal ion has been suggested.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170101
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Kinetics of polymerization of acrylonitrile initiated by the Mn3+-thioacetamide redox system (1980)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 18 (1980), S. 2001-2010 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetics of the polymerization of acrylonitrile has been investigated in aqueous sulfuric acid in a temperature range of 25-45°C. The rate of polymerization (Rp) and the rate of managanic ion disappearance, etc., have been measured. The effect of the various additives, such as water-miscible organic solvents, neutral electrolytes, complexing agents, and surfactants, on the rate has been thoroughly studied. A mechanism that involves the initial complex formation between the thiol form of the thioamide and Mn3+, whose decomposition yields the initiating free radical with the polymer chain terminated by mutual combination of growing radicals, has been suggested.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1980.170180635
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Polymerization of acrylonitrile initiated by thiourea-chromium(VI) redox system (1977)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 15 (1977), S. 2603-2611 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of polymerization of acrylonitrile initiated by Cr(VI)-thiourea and Cr(VI)-ethylene thiourea have been studied at 35, 40, and 45°C in nitrogen. The rates of polymerization and of disappearance of Cr(VI) were measured. Chromic acid alone did not initiate the polymerization under deaerated and undeaerated conditions. On the basis of the experimental observation of the dependence of the rate of polymerization Rp, the rate of Cr(VI) disappearance, -Rm, etc., on various variables, a suitable kinetic scheme was proposed and various rate and energy parameters were evaluated.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1977.170151106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Kinetics of polymerization of acrylonitrile initiated by acidic permanganate/thioacetamide redox system (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2759-2764 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of vinyl polymerization of acrylonitrile (AN) initiated by an acidic permanganate/thioacetamide (TAm) redox system have been investigated in aqueous media at 30 ± 0.2°C in nitrogen, and the rate of polymerization measured. The effect of additives like organic solvents, neutral electrolytes, and complexing agents on the rate have been assessed. Based on the experimental results, a suitable reaction scheme involving initiation by organic free radicals generated by the interaction of Mn(IV) with protonated thioacetamide and termination by Mn(III) has been suggested. Various rate and energy parameters have been evaluated.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170191111
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Acidic peroxo salts. A new class of initiators for vinyl polymerization. I. Kinetics of polymerization of acrylonitrile initiated by potassium monopersulfate catalyzed by Ag(I) (1981)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 19 (1981), S. 2751-2758 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The kinetics of polymerization of acrylonitrile initiated by KHSO5 and catalyzed by Ag(I) have been investigated in an aqueous medium over the temperature range of 35-50°C. The rates of polymerization Rp have been calculated and studied with respect to monomer and initiator. The catalytic activity of various metal ions on the initiator has been determined from a comparison of Rp values. The effects of monomer, catalyst, neutral salts, various amines, and inhibitor (hydroquinone) on the initial rate as well as maximum conversion have been studied. From the kinetics results a suitable reaction scheme has been proposed.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1981.170191110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Polymerization of acrylonitrile. Kinetics of the reaction initiated by the Ce(IV)/thioacetamide redox system (1982)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 53-62 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Vinyl polymerization of acrylonitrile initiated by the Ce(IV)/thioacetamide redox system has been investigated in aqueous sulfuric acid in the temperature range of 10-20°C. The rate of polymerization (Rp) and the rate of Ce(IV) disappearance (-RCe) were measured. The effect of certain water-soluble organic solvents, added electrolytes, and aromatic and heterocyclic organic nitrogen compounds on the rate of polymerization has been investigated. Depending on the experimental results, we have suggested a suitable reaction scheme for the system which involves the production of initiating radicals from the oxidation of thioacetamide (TAm) by ceric ion and the termination of the polymer chain by metal ions.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1982.170200106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Acidic peroxo salts: A new class of initiators for vinyl polymerization. III. Kinetics of polymerization of methyl methacrylate initiated by potassium monopersulfate catalyzed by Co(II) (1982)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 2409-2416 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Kinetics of the polymerization of methyl methacrylate by an acidic peroxo salt like potassium monopersulfate catalyzed by Co(II) have been investigated in aqueous medium, over the range of 35-50°C. The rates of polymerization (Rp) have been studied at various concentrations of monomer and initiator. The efficiencies of various metal salts in catalyzing the polymerization have been evaluated from the observed value of Rp. The effects of catalyst (CoSO4), initiator, monomer, and various concentrations of FeCl3 on Rp and percentage conversion have been studied. The end groups of the recovered polymers have been studied using standard methods. From the observed end groups and kinetic results, a reaction scheme has been proposed involving initiation by SO4· or OH· radicals, generated by the interaction of the initiator with cobalt sulfate and termination of the polymer chains by mutual combination.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1982.170200905
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Graft copolymerization onto wool fibers: Grafting of acrylamide onto wool fibers initiated by potassium monopersulphate/Fe (II) redox system (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 40 (1990), S. 471-483 
    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: Graft copolymerization of acrylamide (AM) onto wool fibers has been studied in aqueous solution with a new redox initiating system, KHSO5/Fe(II). For estimation of comparative influence of salts and selection of reaction medium, grafting has also been studied in the presence of a multitude of inorganic salts and some organic solvents. It was observed that the graft percentage was influenced by the reaction time, temperature, concentration of monomer initiator, FeSO4, and the base polymer. A maximum graft percentage of 120.5% was obtained at 35°C with the concentration of AM (0.8M), KHSO5 (0.0195M) and Fe (II) (2.5 X 10-3 M) for reaction time of 2 h. From the experimental results, a suitable reaction mechanism for graft initiation and termination has been suggested. The water retention of the grafts and their behavior towards mineral acids and alkalis have been tested. The tensile strength and the thermal stability of the grafts have also been determined and compared with the base.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1990.070400314
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...