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  • 1
    Electronic Resource
    Electronic Resource
    Characterization of hydrogen bonding in cellulose-synthetic polymer blend systems with regioselectively substituted methylcellulose (1994)
    s.l. : American Chemical Society
    Macromolecules 27 (1994), S. 210-215 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00079a031
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  • 2
    Electronic Resource
    Electronic Resource
    The assignment of IR absorption bands due to free hydroxyl groups in cellulose (1997)
    Springer
    Cellulose 4 (1997), S. 281-292 
    Details
    ISSN: 1572-882X
    Keywords: FTIR ; free hydroxyl groups ; curve fitting ; hydrogen bonds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract Interpretation of the IR hydroxyl absorption bands in cellulose has been limited to the inter- and intramolecularly hydrogen-bonded hydroxyl groups in the crystalline form. This paper attempts to assign IR frequencies due to ‘free‘ or non-hydrogen bonded hydroxyl groups by using a curve fitting method. The almost completely methylated cellulose derivatives of tritylcellulose (previously used in related studies) exhibited small IR bands due to hydroxyl groups. The IR bands were assumed to appear under stereohindered conditions and thus resulted in a mixture of bands which included the contribution of free hydroxyl groups. The curve fitting method deconvoluted the IR bands into three bands in the OH stretching region: they were interpreted in terms of free or hydrogen bonded hydroxyl groups. The assignments were confirmed by comparison of an almost completely methylated derivative with partially methylated derivatives having different degrees of substitution. In addition, intramolecular hydrogen bonds involving OH at the C-3, C-2 and C-6 positions were shown to be easily formed, even between extremely small numbers of unsubstituted hydroxyl groups present, and thus cause perturbation of the specific deconvoluted band.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018448109214
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  • 3
    Electronic Resource
    Electronic Resource
    Gelation of cellulose whose hydroxyl groups are specifically substituted by the fluorescent groups (1994)
    Springer
    Polymer bulletin 32 (1994), S. 77-81 
    Details
    ISSN: 1436-2449
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Summary The hydroxyl groups of cellulose molecules were specifically substituted by fluorescent probe groups and their fluorescence behavior was studied with the change in the concentration of the THF solution. The results show that the fluorescent probes yield microscopic information on aggregation and that the hydroxyl groups at the 6-position of the cellulose repeating unit play an important role in this gelation process.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00297417
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  • 4
    Electronic Resource
    Electronic Resource
    Preparation of aldehydocelluloses from completely allylated methylcellulose, allylated ethylcellulose, and tri-O-allylcellulose by ozonization (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 35 (1988), S. 885-893 
    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: In order to prepare aldehydocelluloses which are more stable than periodate-oxidized cellulose, completely allylated methylcellulose, allylated ethylcellulose, and tri-O-allylcellulose were subjected to ozonization followed by reduction with dimethylsulfide. The aldehydocelluloses thus prepared without any degradation showed the presence of many free aldehyde groups by IR and 13C-NMR spectrometries, as well as the presence of hydroxyl groups which were produced by deallylation. The degree of substitution (DS) by aldehyde group was 0.6 for the products from both completely allylated methylcellulose and tri-O-allylcellulose, and 0.02 for that from allylated ethylcellulose.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070350404
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  • 5
    Electronic Resource
    Electronic Resource
    Characterization of water-soluble cellulose derivatives produced by alkali treatment of ozonized allylated celluloses (1988)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 36 (1988), S. 1107-1112 
    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: Ozonization products of allylated celluloses such as completely allylated methylcellulose and tri-O-allylcellulose, which are insoluble in both organic solvents and water, gave water-soluble derivatives by alkaline treatment. Infrared (IR) and 13C-NMR (nuclear magnetic resonance) spectrometries revealed that the products have many carboxyl as well as carbonyl groups. Allyl ethers in allylated celluloses were found to be cleaved by 30-35% during ozonization, whereas alkyl ethers such as methyl and ethyl ethers in cellulose derivatives were completely stable.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1988.070360511
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  • 6
    Electronic Resource
    Electronic Resource
    Hydrogen bonds in regioselectively substituted cellulose derivatives (1994)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 32 (1994), S. 1229-1236 
    Details
    ISSN: 0887-6266
    Keywords: hydrogen bond ; intramolecular hydrogen bond ; cellulose ; cellulose derivatives ; FTIR, solid-state CP/MAS 13C-NMR ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: Formation of hydrogen bonds in various cellulose derivatives, 2,3-di-O- and 6-O-substituted cellulose ethers, were characterized by FTIR and solid-state CP/MAS13C-NMR. The polymers were synthesized by regioselective substitution of hydroxyl groups and had a uniform structure. Since their three hydroxyl groups (OH) are selectively blocked, the cellulose derivatives appeared to form specific inter- and intramolecular hydrogen bonds. The characteristic OH stretching frequencies in IR spectra and the C-1 chemical shift in CP/MAS spectra of 6-O-substituted cellulose derivatives indicated existence of two equivalent intramolecular hydrogen bonds between ether oxygen and OH groups at 3-OH-O5′ and O6-HO-2′ [Figure 3(C)]. Influence of the substituents at the C-6 position on the formation was not significant except trityl group. Behavior of the hydrogen bonds in 6-O-tritylcellulose were also discussed. © 1994 John Wiley & Sons, Inc.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/polb.1994.090320710
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  • 7
    Electronic Resource
    Electronic Resource
    The relationship between intramolecular hydrogen bonds and certain physical properties of regioselectively substituted cellulose derivatives (1997)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Physics 35 (1997), S. 717-723 
    Details
    ISSN: 0887-6266
    Keywords: cellulose ; methylcellulose ; hydrogen bond ; intramolecular hydrogen bond ; physical property ; Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: This article tries to provide some direct evidence about the relationship between the intramolecular hydrogen bonds in cellulose and their corresponding effect on physical properties. The formation of intramolecular hydrogen bonds has been proved to contribute directly to certain physical properties of cellulose, such as its solubility in solvents having different polarities, the relative reactivities of the hydroxyls in a repeating unit and its crystallinity, using a 6-O-methylcellulose (6MC) film that was known1 to have intramolecular hydrogen bonds. The excellent solubility of 6MC when compared with other cellulose derivatives indicated a lack of interchain hydrogen bonds. A comparison of the relative reactivities between the C-2 and C-3 position hydroxyls in 6MC also indicates that intramolecular hydrogen bonds once formed in 6MC films are possibly maintained even after dissolution in solvents. In addition, the poor crystallinity exhibited by 6MC supports the idea that crystallization in cellulosics may be dependent more upon preferencial interchain hydrogen bonding at the C-6 position hydroxyls than upon a uniform structure such as that found in 6MC, where every structural unit is completely and regioselectively substituted, distinguishing it from other synthetic polymers such as polyolefins and polyesters. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys, 35: 717-723, 1997
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Facile method for the preparation of tri-O-(alkyl)cellulose (1992)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 45 (1992), S. 417-423 
    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: A simple way to prepare tri-O-(alkyl)cellulose from cellulose acetate (CA) in dimethylsulfoxide (DMSO) using the appropriate alkyl iodide and NaOH has been developed. In this procedure, the addition of a small amount of water to the DMSO solution improved the efficiency of etherification. The substitution pattern of (methyl)cellulose (MC) was investigated to determine the effect of added water on the relative reactivities of the glucose ring substituents. This etherification method can be applied to alkylate other polymers with acetate-functional groups that are soluble in DMSO.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1992.070450306
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  • 9
    Electronic Resource
    Electronic Resource
    Preparation of glycidyl celluloses from completely allylated methylcellulose and tri-O-allylcellulose (1989)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 37 (1989), S. 3003-3009 
    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: Glycidyl celluloses were prepared from completely allylated methylcellulose and tri-O-allylcellulose with m-chloroperbenzoic acid in homogeneous chloroform solutions. The degrees of substitution (DS) by epoxy groups were 0.60 and 1.33 for the products prepared from allylated methylcellulose and tri-O-allylcellulose, respectively. They were soluble in not only many organic solvents, but also methanol-water mixtures [more than 70% (v/v)]. These products were characterized by infrared spectroscopy (IR), 13C-NMR spectroscopy, and gel permeation chromatography (GPC).
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1989.070371017
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  • 10
    Electronic Resource
    Electronic Resource
    Preparation of completely allylated and methallylated celluloses from methylcellulose and cellulose acetate (1987)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 34 (1987), S. 55-63 
    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: Cellulose ethers having various amounts of carbon - carbon double bonds were prepared by allylation or methallylation of commercial methylcellulose (DS = 1.6). Namely, methylcellulose dissolved in dimethylsulfoxide (DMSO) was treated with allyl chloride or methallyl chloride in the presence of powdered sodium hydroxide as a base. Tri-O-allyl and tri-O-methallyl celluloses were also prepared easily from commercial cellulose acetate (DS = 1.75) with powdered sodium hydroxide and the corresponding chlorides. Thermal stabilities of these cellulose derivatives and their behaviors to oxygen in the air were studied by the use of TG-DSC and solubility test, respectively.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1987.070340105
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