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  • 1
    Electronic Resource
    Electronic Resource
    Structure-Activity Relationship of .alpha.-Galactosylceramides against B16-Bearing Mice (1995)
    s.l. : American Chemical Society
    Journal of medicinal chemistry 38 (1995), S. 2176-2187 
    Details
    ISSN: 1520-4804
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/jm00012a018
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  • 2
    Electronic Resource
    Electronic Resource
    Dynamic fluorescence quenching precedent to thermally-induced phase separation of poly(ethoxyethyl vinyl ether) aqueous solution (1999)
    Springer
    Polymer bulletin 42 (1999), S. 85-91 
    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 We focused on the stage preceding the thermally-induced phase separation of aqueous solution of poly(ethoxyethyl vinyl ether) (PEVE). Previously, we observed an interesting dynamic quenching just below the phase separation temperature. The dynamic fluorescence quenching disappeared by addition of a surfactant. In systems without the phase separation of both the hexane solution of PEVE and the PEVE bulk, the fluorescence lifetime decreased monotonically with the increase of temperature. These results indicated that the marked decrease is due to the dynamic quenching by the collision between the fluorescent probe and the PEVE segment induced by the thermal fluctuation precedent to the phase separation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002890050438
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  • 3
    Electronic Resource
    Electronic Resource
    Optically active alternating copolymer and Diels-Alder adduct (1980)
    Springer
    Polymer bulletin 3 (1980), S. 285-290 
    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 Asymmetric induction copolymerization and Diels-Alder reaction were investigated between acrylic monomer and olefin or diolefin with use of an optically active aluminum compound as the complexing agent. In the copolymerization, only benzofuran gave an optically active alternating copolymer, while butadiene and indene gave alternating copolymers but with no optical activity. EtAlCl2-l-menthol was the most effective complexing agent. However, EtAlCl2-d-neomenthol was ineffective. On the other hand, Diels-Alder reaction was in general more easily stereocontrolled. For instance, both complexing agents were effective for the synthesis of optically active Diels-Alder adducts with butadiene or cyclopentadiene, perhaps due to the rigid cyclic structure in a transition state of the reaction.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00254875
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  • 4
    Electronic Resource
    Electronic Resource
    220-MHz NMR spectra of acrylic monomer-2-substituted 1,3-diolefin alternating copolymers (1976)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 14 (1976), S. 2553-2563 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An investigation by 220-MHz NMR spectroscopy was carried out on the alternating copolymers of acrylic monomer with 2-substituted 1,3-diolefin. The chain structures were determined. The acrylic monomers used were methyl methacrylate (MMA), acrylonitrile (AN), and methacrylonitrile (MAN); isoprene (IP) and chloroprene (CLP) were the 1,3-diolefins. In the MAN-IP alternating copolymer, the 1-position methylene protons of IP showed an AB quartet peak, confirming the α-1 linkage structure. Similarly, in the MMA-CLP and AN-CLP copolymers, the 1-position methylene protons of CLP showed and AB quartet and an ABX pattern, respectively, confirming the α-1 linkage structure in both these cases also. The α-1 linkage structure was also revealed by the decoupling technique in the MAN-CLP alternating copolymer. The AN-IP and MMA-IP alternating copolymers also possess a bond between the α-position of the acrylic monomer and the 1-position of IP. The monomeric units in the alternating copolymers of acrylic monomers with 2-substituted 1,3-diolefins were generally linked at the α-position of acrylic monomer and the 1-position of 1,3-diolefin. On the other hand, in the Diels-Alder adducts of acrylic monomer with 2-substituted 1,3-diolefin, the reaction takes place between the α-position of acrylic monomer and the 4-position of 1,3-diolefin.The regioselectivity of the alternating copolymers and the Diels-Alder adducts is quite compatible with the expectations from molecular orbital theory.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1976.170141020
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  • 5
    Electronic Resource
    Electronic Resource
    1H-NMR spectra of complexes between methacrylic monomer and ethylaluminium dichloride in toluene and methylene chloride (1976)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 14 (1976), S. 237-255 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: 1H-NMR spectra of mixtures of a methacrylic monomer such as methacrylonitrile or methyl methacrylate and ethylaluminium dichloride at various molar ratios were measured in toluene or methylene chloride at various temperatures. It was found that only one kind of binary complex is detectable in the methacrylonitrile-ethylaluminum dichloride equimolar mixture, while in nonequimolar systems there are several kinds of binary complexes, depending on the molar ratio at low temperature in these solvents. Moreover, the chemical shifts of the protons of methacrylonitrile due to complex formation with ethylaluminum dichloride show a remarkable temperature dependence in toluene, but not in methylene chloride. This fact can be interpreted by an assumption of the formation of a ternary complex of methacrylonitrile, ethylaluminum dichloride, and aromatic donor molecules, mainly due to the dipole interaction between the nitrile group complexed with ethylaluminum dichloride and aromatic donor. The orientation of toluene molecules in the ternary complex of methacrylonitrile or methyl methacrylate is discussed.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1976.170140120
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  • 6
    Electronic Resource
    Electronic Resource
    Alternating polyampholytes prepared by hydrolysis of copolymer of maleic anhydride and N-vinylsuccinimide (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 255-266 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Alternating polyampholytes (MA-VA) containing two acidic groups and one basic group were prepared by the copolymerization of maleic anhydride (M1) and N-vinylsuccinimide (M2) at 60°C with AIBN as the initiator, followed by acid hydrolysis with 1N hydrochloric acid at 140°C for 24 hr. The monomer reactivity ratios r1 and r2 are 0.025 and 0.06, respectively. The structure of polymers was discussed on the basis of the data of their elementary, infrared (IR), and thermal analyses and the binding ability of heavy metal ion. Polyampholytes were soluble in strong acidic and basic media but were precipitated in the pH range 3-4. An isoelectric point at pH 3 was determined by potentiometric titration and the turbidimetric method. By thermal treatment above 205°C the polyampholyte turned quantitatively into a cyclized lactam. This suggests that the polyampholyte MA-VA has an intramolecular hydrogen bond between the amino and γ-carboxyl groups. The binding of Cu2+ and Hg2+ by the polyelectrolyte was evaluated by equilibrium dialysis.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170125
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  • 7
    Electronic Resource
    Electronic Resource
    Studies on the optical active alternating copolymer of benzofuran or 1,3-cyclooctadiene with acrylic monomers (1979)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 17 (1979), S. 2093-2101 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: In the presence of an optical active amyloxyaluminum or menthoxyaluminum chloride the asymmetric-induction alternating copolymerization of benzofuran or 1,3-cyclooctadiene and acrylonitrile or methacrylonitrile was investigated. The sign of optical rotation of copolymers was positive or negative, depending on the kind of catalyst used. The optical activity of copolymers of benzofuran and acrylonitrile attains a maximum value at an equimolar composition. The highest specific rotation [α]D of copolymers of benzofuran and acrylonitrile prepared in the presence of stoichiometric amount of ( - )-menthoxyaluminum dichloride with respect to acrylonitrile was about -8°. The stereo-structure of acrylonitrile unit may be controlled by the optical active aluminum compound onto which a strong coordination of acrylonitrile may occur.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1979.170170718
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  • 8
    Electronic Resource
    Electronic Resource
    Random copolymerization of acetylenic monomers and 1,3-dienes (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 1609-1625 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Copolymerization of acetylenic monomers and 1,3-dienes was carried out by use of nickel naphthenate-diethylaluminum chloride catalyst. The molecular weight of the copolymers is rather low, and the copolymers are suitable as prepared for direct use as coating vehicles. In the system of acetylene and 1,3-dienes, the order of the copolymerization rate decreases in the following order: butadiene 〉 isoprene 〉 2,3-dimethylbutadiene 〉 chloroprene. 1,3-Dienes substituted at 1-and/or 4-position were scarcely copolymerized with acetylene. Methylacetylene and dienes tend to form cyclized copolymers. In the system of phenylacetylene and dienes, polyphenylacetylene was the main product; the copolymer was not obtained. The copolymer composition and the sequence distribution of linear copolymers were evaluated by 1H-NMR spectra. Comparison of dyad fractions of copolymers evaluated from NMR spectra and those calculated by assuming random polymerization indicated that the copolymers of acetylene and dienes were random, and that the copolymers of methylacetylene and dienes were somewhat blocky. The coordination of monomers on the catalyst may play an important role in controlling the copolymerizability.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170160715
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  • 9
    Electronic Resource
    Electronic Resource
    Effect of ultraviolet irradiation on terpolymerization of sulfur dioxide with two unsaturated compounds (1974)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 12 (1974), S. 1851-1859 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The terpolymerization of sulfur dioxide, butene-1 and acrylonitrile affords terpolymers containing equimolar amounts of sulfur dioxide and butene-1 with various acrylonitrile contents. Ultraviolet irradiation was found to accelerate the polymerization and decrease the acrylonitrile content in the polymer. This fact is interpreted by a mechanism through a copolymerization of sulfur dioxide-butene-1 complex and acrylonitrile, whereby the polymerizability of sulfur dioxide-butene-1 complexed monomer may be accelerated by ultraviolet light. In fact, a binary system of sulfur dioxide and butene-1 was found to be accelerated by ultraviolet irradiation, and it affords a maximum rate at a 1:1 composition of feed monomer. Ultraviolet light of 250-300 mμ wavelength is effective for the initiation and the propagation. This may be ascribed to the ultraviolet absorption of the sulfur dioxide-butene-1 complex. The temperature coefficient was measured in both dark and ultraviolet irradiation reactions. The ultraviolet irradiation enhances the reactivity of sulfur dioxide-butene-1 complexed monomer at low temperature. In the terpolymerization with sulfur dioxide, isoprene, and butadiene, the ratio of isoprene and butadiene in the terpolymer was not altered by ultraviolet irradiation because both monomers from complexes with sulfur dioxide, perhaps having the same temperature coefficient for the polymerization.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1974.170120825
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  • 10
    Electronic Resource
    Electronic Resource
    Alternating copolymerization of benzofuran with crotononitrile and α-chloroacrylonitrile (1978)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 16 (1978), S. 2955-2964 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The copolymerizations of benzofuran with α,α- or α,β-disubstituted acrylic monomers were studied. The alternating copolymer of benzofuran and crotononitrile was prepared in the presence of an excess amount of crotononitrile with respect to benzofuran, ethylaluminum dichloride, and azobisisobutyronitrile. The intrinsic viscosity of copolymers was 0.1-0.2 dl/g. Crotononitrile is known to possess a polar carbon-carbon double bond from 13C-NMR spectroscopy but the alternating copolymerizability with benzofuran is low. It was found that the order of alternating copolymerizability of acrylic monomers is as follows: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm CIAN 〉 AN 〉 MAN 〉 }cis{\rm - CrN 〉 }trans{\rm - CrN} $$\end{document} This fact may be attributed to the steric hindrance of the β-methyl of crotononitrile. The induced shifts by complexation with ethylaluminum dichloride on 13C-NMR spectra of the two isomers of crotononitrile are almost same but the copolymerizability of cis isomer is higher than that of trans isomer.α-Chloroacrylonitrile shows the highest alternating copolymerizability with benzofuran in the presence of weak Lewis acid such as ethoxyaluminum chloride. Alternating copolymerizability of acrylic monomers seems to be in proportion to their e value. The reactivity of cis- and trans-crotononitrile may depend on the nature of a ternary complex composed of aluminum compound, crotononitrile, and benzofuran.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1978.170161120
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