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  • 1
    Electronic Resource
    Electronic Resource
    The Unperturbed Dimensions of Polypropylene and Polyethylene1 (1966)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 70 (1966), S. 3420-3431 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100883a009
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  • 2
    Electronic Resource
    Electronic Resource
    Orientation-Dependent Interactions in Polymer Systems. 4. Chain-Length Dependence of the Nematic-Isotropic Transition Behavior of Thermotropic Semiflexible Polymers (1995)
    s.l. : American Chemical Society
    Macromolecules 28 (1995), S. 3387-3393 
    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/ma00113a044
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  • 3
    Electronic Resource
    Electronic Resource
    Orientation-Dependent Interactions in Polymer Systems. 5. Thermotropic Liquid Crystalline Transition of Tri-O-heptylcellulose (1995)
    s.l. : American Chemical Society
    Macromolecules 28 (1995), S. 3394-3400 
    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/ma00113a045
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  • 4
    Electronic Resource
    Electronic Resource
    Thin Layer Chromatographic Studies on Specific Interactions between Stereoisomeric Chains of Poly(methyl methacrylate) (1969)
    s.l. : American Chemical Society
    Macromolecules 2 (1969), S. 554-556 
    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/ma60011a022
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  • 5
    Electronic Resource
    Electronic Resource
    Phase transition of 2,3-O-methylcellulose (1998)
    Springer
    Polymer bulletin 40 (1998), S. 741-747 
    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 In this work, a series of 2,3-O-methylcellulose (MC) with different DS value were prepared. Its phase transition behavior in aqueous solution was studied in terms of DS value, concentration and molecular weight. The the following conclusions were obtained. (1) All the 2,3-O-MC samples show no sol-gel transition in aqueous solution despite the molecular weight. (2) No phase separation was observed for the 2,3-O-MCs with a DS value lower than 1.0, even when the temperature was raised to 95°C. (3) The precipitation temperature is surprisingly different between 2,3-O-MCs. and other MCs possessing comparable total DS value. (4) The precipitation temperature of 2,3-O-MCs depends on the molecular weight rather than on the concentration.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002890050317
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  • 6
    Electronic Resource
    Electronic Resource
    Effect of substituent distribution on water solubility of O-methylcellulose (1997)
    Springer
    Cellulose 4 (1997), S. 321-327 
    Details
    ISSN: 1572-882X
    Keywords: O-methylcellulose ; water solubility ; substituents distribution ; regioselective substitution ; hydrogen bonding
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract The effect of substituent distribution on the water solubility of O-methylcellulose (MC) was re-examined to elucidate the lower limit of the degree of substitution (DS) in water-soluble MC. To this end, a series of 2,3-MCs which are regioselectively substituted at the C-2 and C-3 hydroxyl groups were prepared by homogeneous methylation. It was found that the lower limit for the DS value of water-soluble 2,3-MC was almost the same as that for MCs having even distributions of substituents along the cellulose chain as well as in the anhydroglucose units.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1018404426960
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  • 7
    Electronic Resource
    Electronic Resource
    Reaction characteristics of cellulose in the LiCl/1,3‐dimethyl‐2‐imidazolidinone solvent system (1999)
    Springer
    Cellulose 6 (1999), S. 93-102 
    Details
    ISSN: 1572-882X
    Keywords: LiCl/1 ; 3‐dimethy‐2‐imidazolidinone solvent system ; homogeneous cellulose solution ; cellulose acetate ; O‐methylcellulose ; reaction characteristics
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract In order to elucidate the nature of the LiCl/1,3‐dimethy‐2‐imidazolidinone (DMI) solvent system as one of the homogeneous reaction media of cellulose, cellulose acetate (CA) and O‐methylcellulose (MC) were prepared using this solvent system, and the distribution of substituents within anhydroglucose units was examined by 13C‐NMR. It was found that (i) homogeneous cellulose solutions can be easily prepared by heating 2, 5–12 and 100 parts of weight of cellulose, LiCl, and DMI, respectively, and (ii) the relative reactivity of hydroxyl groups is in the order C‐6 〉 C‐2 〉 C‐3 for both CA and MC. A remarkable feature of this solvent system is that the reaction efficiency in etherification is very high compared with other homogeneous solvent systems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009208417954
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  • 8
    Electronic Resource
    Electronic Resource
    Separation of trans-1,4, cis-1,4 and 1,2-vinyl polybutadienes by thin layer chromatographyDedicated to Professor Dr. ICHIRO SAKURADA at the occasion of his 70th birthday (1974)
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 175 (1974), S. 187-195 
    Details
    ISSN: 0025-116X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Description / Table of Contents: Es wurde eine Untersuchung über die dünnschicht-chromatographische Trennung von Polybutadienpräparaten mit den drei unterschiedlichen Mikrostrukturen, trans-1,4-, cis-1,4-und 1,2-Vinyl, durchgeführt. Um diese drei Polymerproben chromatographisch zu trennen, wurde ein experimentelles Verfahren ausgearbeitet, bei dem Tetrachlorkohlenstoff und Amylchlorid wechselweise als Laufmittel verwendet wurden. Ferner wurde gezeigt, daß dieses Verfahren in Kombination mit einer zweidimensionalen Entwicklungstechnik eine Auftrennung des ternären Polymergemisches in die einzelnen Komponenten ermöglicht. Dazu wurde das chromatographische Verhalten von sogenannten „equibinären“ Polybutadienen unter Anwendung des bislang ausgearbeiteten Verfahrens untersucht.
    Notes: A study on thin layer chromatographic (TLC) separation of polybutadienes with three different microstructures, namely, trans-1,4, cis-1,4, and 1,2-vinyl, was carried out. An experimental procedure to separate three possible binary mixtures of these polymers into each component species is established in an alternate use of carbon tetrachloride and amyl chloride as developer. Further it is shown that this procedure combined with a two-dimensional TLC development technique allows to separate the ternary polymer mixture into components. In addition, the chromatographic behavior of so-called “equibinary” polybutadienes has been investigated using the technique established so far.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/macp.1974.021750120
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  • 9
    Electronic Resource
    Electronic Resource
    Structural and steric isomerism of polypropylenesThis work was presented in part at the 16th Polymer Symposium, Fukuoka, Japan, October 1967. (1969)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A-2: Polymer Physics 7 (1969), S. 963-981 
    Details
    ISSN: 0449-2978
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The structural and steric isomerism of propylene polymers has been estimated on the basis of solution properties as well as infrared and high-resolution nuclear magnetic resonance spectra. Three general types of polypropylenes were prepared: polymers prepared with the cationic catalytic system AlCl3-C2H5Cl, stereoblock polymers obtained by successive extraction from a commercial product and isotactic polymers of low molecular weight obtained by thermal degradation of a highly isotactic polymer followed by hydrogenation with Adam's catalyst in dioxane at 40°C. The characterization of all samples was accomplished by equilibrium ultracentrifugation, vapor-pressure osmometry, viscometry, and gel-permeation chromatography. It is found that the molecular chain of cationically prepared polymer is somewhat branched owing to structural isomerism during polymerization. Isoamyl acetate is found to be a theta solvent for stereo-block as well as for atactic and syndiotactic polymers; the theta temperature is determined as the temperature at which the light-scattering second virial coefficient A2 vanishes. A close correlation is found between the theta temperature and stereoisomerism. The absorbances of the 1154 and 974 cm-1 bands in the infrared spectra decrease with decreasing molecular weight; in addition to the mere existence of alternating CH2 and CH(CH3) groups in the polymer chain, rather long sequences of this type are required for the appearance of these bands. Changes in the absorption band at 997 cm-1 show that chains consisting of over ten isotactically connected monomer units can assume a helical conformation. From the high-resolution NMR spectra of different polypropylenes, including isotactic polymers of low molecular weight, it is found that in estimating the microstructure, account must be taken of the effects of stereoisomerism within tetrads of monomer units on the apparent widths of the methylene proton resonances. If substantial concentrations of several of the possible types of tetrads are present (i.e., if the tactic sequence lengths are quite short), then it is difficult to determine the relative amounts of tactic dyads accurately from the 100 Mcps methylene proton resonances.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1969.160070601
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  • 10
    Electronic Resource
    Electronic Resource
    Controlled synthesis of amphiphilic block copolymers with pendant glucose residues by living cationic polymerization (1997)
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 35 (1997), S. 255-261 
    Details
    ISSN: 0887-624X
    Keywords: controlled synthesis ; amphiphilic block copolymer ; pendant glucose residues ; vinyl ether ; living cationic polymerization ; microphase-separated structure ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Amphiphilic block copolymers of vinyl ethers (VEs) of the type  - [CH2CH(OCH2CH2OR)]m - [CH2CH(OiBu)]n - were synthesized by living cationic polymerization, where R is a D-glucose residue, and m and n are the degrees of polymerization (m = 20-50; n = 11-89). To obtain them, sequential living block copolymerization of isobutyl vinyl ether (IBVE) and the vinyl ether carrying 1,2:5,6-diisopropylidene-D-glucose residue was conducted by using the HCl adduct of IBVE, CH3CH(OiBu)Cl, as initiator in conjunction with zinc iodide. These precursor block copolymers had a narrow molecular weight distribution (M̄w/M̄n ∼ 1.1) and a controlled composition. Treatment of them with a trifluoroacetic acid/water mixture led to the target amphiphiles. The solubility of the amphiphilic block copolymers in various solvents depended strongly on composition or the m/n ratio. Their solvent-cast thin films were observed, under a transmission electron microscope, to exhibit various microphase-separated surface morphologies such as spheres, cylinders, and lamellae, depending on composition. © 1997 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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