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  • 1
    Electronic Resource
    Electronic Resource
    Some Relations between Intrinsic and Specific Viscosity in Cellulose Solutions at a Controlled Velocity Gradient (1952)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 56 (1952), S. 693-696 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j150498a007
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  • 2
    Electronic Resource
    Electronic Resource
    Intrinsic Viscosities of Cellulose as Affected by Rate of Shear. (1951)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 55 (1951), S. 1474-1491 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j150492a007
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  • 3
    Electronic Resource
    Electronic Resource
    ESR spectra of copper complexes of cellulose (1968)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 12 (1968), S. 249-265 
    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 ESR spectra of complexes of fibrous cotton cellulose and cupriammonia dihydroxide or cupriethylene diamine dihydroxide under various experimental conditions were determined. The spectra of both complexes with cotton cellulose were almost identical at -100 and 25°C. The spectrum of the complex of cupriethylene diamine dihydroxide with cellulose was stable to temperatures as high as 100°C. The sum of the linewidths of the hyperfine components of the spectra for each complex was about 180 gauss. Cotton fibers were combed and aligned with their axes (lengths) parallel to the magnetic field (B∥); after formation of either of the complexes with cellulose a minumum of hyperfine structure of components centered at H∥ was observed. A maximum of hyperfine structure of these components was observed when the complexed fibers were aligned with their axes perpendicular to the magnetic field (B⊥). The opposite was true of components centered at H⊥. For a complex of cupriethylene diamine dihydroxide and cellulose at 25°C. and at high pH the g∥ was 2.2127 and the g∥ was 2.0476. It was suggested that the alignment of most of the complex was its axis of symmetry at a maximum angle to the axes of the cotton fiber, when the axes of the fibers were in the parallel alignment with the magnetic field. At high pH these observations were even more marked. When ramie was used with cupriethylene diamine dihydroxide at high pH, the contribution of components centered at H∥ to the spectra was zero. Spectra for the copper compounds alone and complexed with cellobiose are also reported.
    Additional Material: 16 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1968.070120202
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  • 4
    Electronic Resource
    Electronic Resource
    Intramolecular transfer of high energy in cellulose (1965)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 9 (1965), S. 2581-2590 
    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 intramolecular transfer of high energy in purified cotton cellulose has been demonstrated to occur over distances several times greater than the length of the b axis of a cellobiose unit. The electron spin resonance spectra of fibrous benzoylated cotton cellulose have shown that the concentrations of free radicals initiated in the cellulosic molecule by γ-radiation from Co60 are decreased by the presence of substituted benzoyl groups spaced at least as far apart as 70-80 A. The retention of the breaking strength of fibrous cotton cellulose on exposure to γ-radiation is increased by substitution of benzoyl groups on the cellulose molecule. The substitution of benzoyl groups, spaced at least as far apart as 10-20 A., results in about 80% retention of the initial strength of the fibrous cellulose at dosages as high as 1.3 × 1021 e.v./g. cellulose, as compared with about 20% retention of the initial strength of unsubstituted cellulose at the same dosage. Based on the breaking strengths of the irradiated fibrous celluloses, at a dosage of 1.3 × 1021 e.v./g. cellulose, the average calculated distances between molecular cleavages are increased from about 500 A. for unsubstituted cellulose to about 3000 A. for benzoylated cellulose (degree of substitution 2.0). These energy transfer effects in cellulose of high molecular weight indicate that polymeric carbohydrates can be radioprotected.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1965.070090719
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  • 5
    Electronic Resource
    Electronic Resource
    Effect of aromatic groups on localization of high energy in cellulose (1967)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 11 (1967), S. 1129-1138 
    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: When γ-radiation from 60Co interacted with fibrous cotton cellulose, the localization of at least part of the high energy resulted in cellulosic chain cleavage and loss in breaking strength of the irradiated fibers. The substitution of aromatic groups on the cotton cellulose molecule affected this localization of energy and decreased the radiation degradation of the fiber. The nature of the linkage of the aromatic group to the cellulose molecule was not as important as the radiation stability of the linkage. For example, if localization of energy occurred which cleaved the aromatic group from the cellulose molecule, the radioprotection of the cellulosic molecular chain by the aromatic group was not effective. If the aromatic group was so modified that the effective number of π-electrons was decreased, the radioprotection of the cellulosic chain was also decreased. The radioprotection of the cellulosic molecular chain by benzhydryl, trityl, benzoyl, and cinnamoyl groups was effective over distances equivalent to several cellobiose units. The radioprotection of the cellulosic chain by naphthoyl groups was significant but not as effective as the listed groups. Due to the sharing of π-electrons in the naphthoyl group, the effective number of π-electrons was reduced, and consequently the radioprotective effect of the group was also reduced. Benzyl groups were cleaved from the cellulose molecule on irradiation and offered no radioprotection to the cellulosic chain, at least at the high radiation dosages used. The ESR spectra of the irradiated celluloses, both substituted and unsubstituted, were similar. This indicated that the presence of aromatic groups did not change the nature of the long-lived free radicals induced in cellulose on irradiation. It was suggested that selective energy absorption by the aromatic group from the spur of high-energy electrons produced on interaction of γ-radiation with the cellulose molecule could account for the radioprotection of the cellulosic molecular chain.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1967.070110711
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  • 6
    Electronic Resource
    Electronic Resource
    Electron spin resonance studies of interactions of ammonia, copper, and cupriammonia with cellulose (1974)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 18 (1974), S. 2509-2516 
    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 electron spin resonance spectra (ESR) of complexes of copper with fibrous cotton cellulose under various experimental conditions were determined. Cupric ions dissolved in solutions of strong bases, such as concentrated ammonium hydroxide, sodium hydroxide, and potassium hydroxide, formed complexes with fibrous cotton cellulose. These complexes had paramagnetic resonance properties and generated characteristic ESR spectra. Cupric ions dissolved in solutions of highly ionized neutral salts, such as sodium chloride, formed complexes with cellulose. These complexes also generated the same characteristic ESR spectra as the complexes formed in solutions of strong base. The reaction between cupric ions and cellulose was evidently very rapid and reversible. When the concentration of ammonia was decreased in, or ammonia was removed from, the cupric ion-ammonium hydroxide-cellulose complexes, the paramagnetic resonance properties of the complex were decreased or lost. Similar results were received when potassium hydroxide was removed from the complexes. The compositions of the complexes evidently are variable, that is, under different experimental conditions the relative intensities of the lines of the ESR spectra of the complexes varied, although the hyperfine splittings of the lines were constant. It was concluded that reactions of cupric ions to form complexes with adjacent hydroxyl groups on the cellulose molecule depended on an optimum spatial arrangement of the hydroxyl groups, that is, distance between the groups. Evidently, wetting of cotton cellulosic fibers with solutions of strong bases or neutral salt allowed rotation about the C2-C3 bond to yield this optimum arrangement. When the base or salt was removed, rotation occurred to give less favorable positions of the hydroxyl groups for complexing with cupric ions.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1974.070180829
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  • 7
    Electronic Resource
    Electronic Resource
    Cellulose graft copolymers. IV. Graft copolymerization of methacrylonitrile with γ-irradiated cellulose from DMSO-, acetone-, and methanol-water systemsPresented in part at the 7th Annual Meeting-in-Miniature of the Louisiana Section of the American Chemical Society, New Orleans, Louisiana, April 3, 1970. (1971)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 15 (1971), S. 2349-2356 
    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: Methacrylonitrile was graft-copolymerized from DMSO-, acetone-, and methanol-water systems with γ-irradiated, purified cotton cellulose. The relative extents of scavenging of the free radicals in the irradiated cellulose after immersion in the solvents for 3 min at 25°C, as determined by electron spin resonance spectroscopy, were: methanol (77%) 〉 water (70%) ≫ acetone (5%) 〉 DMSO (0%). After immersion of irradiated cellulose in the solvents for 60 min at 25°C, the relative extents of scavenging of the radicals were: methanol, water (80-85%) 〉 DMSO (80%) 〉 acetone (62%). From these data, it would appear that the overall rates of diffusion of methanol and water into the fibrous macrostructure were greater than the rates of diffusion of DMSO and acetone into the structure. The relative radiochemical yields of the graft copolymerization reactions of methacrylonitrile with irradiated cellulose in the different solvents were: water ≫ DMSO 〉 methanol ≫ acetone. The addition of water to the systems increased the yields of the reactions.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1971.070151003
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  • 8
    Electronic Resource
    Electronic Resource
    Methanolysis and hydrolysis of cotton cellulose IIIPresented before the Division of Cellulose Chemistry at the 127th meeting of the American Chemical Society, Cincinnati, Ohio, March 27-April 7, 1955. (1956)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 20 (1956), S. 29-36 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Well-decrystallized cotton yarn, the remaining organized regions of which consisted predominantly of crystalline cellulose III, was subjected to partial solvolysis in aqueous and methanolic hydrochloric acid. From x-ray examination of the residues a hypothesis is advanced regarding the reversion of cellulose III to cellulose I. The viscometric data indicated identical values of leveling-off degree of polymerization by hydrolysis and by methanolysis, which is at variance with certain published data showing lower values for methanolysis. The data therefore neither support nor disprove the idea of recrystallization during hydrolysis, but indicate the need for further work along these lines.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1956.120209403
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  • 9
    Electronic Resource
    Electronic Resource
    Radiation-initiated crosslinking of cellulose (1969)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Letters 7 (1969), S. 419-425 
    Details
    ISSN: 0449-2986
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1969.110070603
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