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  • 11
    Electronic Resource
    Electronic Resource
    Synthesis and activity of phase-transfer catalysts supported on polystyrene-polypropylene composite fiber (1984)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Rapid Communications 5 (1984), S. 685-688 
    Details
    ISSN: 0173-2803
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1984.030051015
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  • 12
    Electronic Resource
    Electronic Resource
    Synthesis of microporous and macroreticular polystyrene resins containing epoxy groups (1987)
    Basel : Wiley-Blackwell
    Die Makromolekulare Chemie, Rapid Communications 8 (1987), S. 339-343 
    Details
    ISSN: 0173-2803
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/marc.1987.030080705
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  • 13
    Electronic Resource
    Electronic Resource
    Phase-transfer reactions catalyzed by phosphonium salts attached to polystyrene resins by spacer chains (1982)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3421-3429 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of reaction of 1-halooctanes with aqueous sodium cyanide catalyzed by phosphonium salts attached to insoluble polystyrene resins by tetramethylene or heptamethylene spacers was studied as a function of catalyst particle size, degree of polymer crosslinking, percentage of ring substitution, and temperature. Rates of reaction of 1-bromooctane with 17-38% ring-substituted catalysts increased as spacer-chain length increased. Rates of reaction of 1-bromooctane decreased, whether the percentage of ring substitution increased or decreased from 17-19%. Rates of reaction of 1-chlorooctane increased with increasing spacer-chain length and decreasing percentage of ring substitution. Apparent activation energy for the reaction of 1-bromooctane with 9% ring-substituted, spacer-modified catalysts was 9-10 kcal/mol and 13 kcal/mol with 17-19% ring-substituted catalysts. The hydrophilicity of catalysts decreased with increasing spacer-chain length and decreasing percentage of ring substitution. The mechanisms of reaction were discussed in terms of intrinsic reactivity and intraparticle diffusion limitations on the reaction rates.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1982.170201214
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  • 14
    Electronic Resource
    Electronic Resource
    Phase-transfer reactions catalyzed by phosphonium salts bound to macroporous polystyrene supports (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 1243-1250 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The rate of reaction of alkyl halides with aqueous sodium acetate or cyanide catalyzed by phosphonium salts supported on insoluble polystyrene resins, and rates of ion-exchange of the chloride ion in the catalysts against the acetate ion, were studied as a function of catalyst particle size, the percentage of ring substitution, the morphology of polymer support, and distance between active site and polymer backbone. Rates of 1-bromooctane or benzyl chloride with macroporous, 7-25% ring-substituted catalysts increased with increasing ring substitution. Rates with macroporous catalysts increased as a heptamethylene spacer was introduced between the active site and the polymer backbone. Rates of ion-exchange with macroporous catalysts were facilitated with increasing ring substitution or by the introduction of the spacer chain. A relation between the catalytic activity of macroporous or microporous catalysts and ion-exchange rates under triphase conditions was discussed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.170220604
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  • 15
    Electronic Resource
    Electronic Resource
    Novel synthesis of spacer-modified polymer supports and activity of phase-transfer catalysts derived from the polymer supports (1982)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 20 (1982), S. 3015-3019 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1982.170201028
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  • 16
    Electronic Resource
    Electronic Resource
    Solvent effects in phase-transfer reactions prompted by polymer-supported phosphonium salts (1985)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 23 (1985), S. 49-61 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Solvent effects on the intrinsic activity of, the ion-exchange rate of, and the overall activity of polymer-supported phosphonium salts under tri-phase conditions were studied. The intrinsic activity of the catalysts as well as of soluble phosphonium salts was dependent only slightly on organic solvents. The exchange rate of the chloride ion in the catalysts against the acetate ion dependent on the solvents when the degree of ring substitution was ≤ 16%. With the ca. 30% ring-substituted catalysts the rate increased and hardly depended on the solvents. The overall reactivity of the catalysts for the reaction of organic halides with NaCN was a function of substrate structure and organic solvents. For alkyl halides such as bromooctane the catalysts were more reactive in good solvents such as toluene or chlorobenzene than in poor solvents such as octane. For arylalkyl halides such as benzyl chloride the catalysts exhibited the opposite effect. In poor solvents the arylalkyl halides are absorbed preferentially into the catalysts.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1985.170230106
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  • 17
    Electronic Resource
    Electronic Resource
    Phase-transfer reactions catalyzed by polymer-supported crown ethers (1984)
    New York : Wiley-Blackwell
    Journal of Polymer Science: Polymer Chemistry Edition 22 (1984), S. 911-926 
    Details
    ISSN: 0360-6376
    Keywords: Physics ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Polymer-supported crown ethers were prepared from chloromethylated or ω-bromoalkylated polystyrene resins and hydroxymethylbenzo-18-crown-6 and 15- or 18-membered monoazacrown ethers. Effects of the cavity size of crown ethers, the degree of crosslinking, the degree of ring substitution, particle size, spacer chains, and solvents on the activity of the polymer-supported crown ethers in the reaction of 1-chloro- or 1-bromo-octane with aqueous NaI or KI were investigated and mechanisms of the reaction were discussed in terms of mass transfer, intraparticle diffusion, and intrinsic reactivity.
    Additional Material: 7 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1984.170220403
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  • 18
    Electronic Resource
    Electronic Resource
    Toughening of aromatic diamine-cured epoxy resins by modification with hybrid modifiers composed of N-phenylmaleimide-styrene copolymers and N-phenylmaleimide-styrene-p-hydroxystyrene terpolymers (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Polymer International 38 (1995), S. 343-352 
    Details
    ISSN: 0959-8103
    Keywords: epoxy resin ; p,p′-diaminodiphenyl sulphone ; modification ; influence of hybrid modifier compositions ; fracture toughness ; 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: Hybrid modifiers composed of N-phenylmaleimide-styrene copolymers (PMS), and N-phenylmaleimide-styrene-p-hydroxystyrene terpolymers (PMSH) containing pendent p-hydroxyphenyl groups as functionalities, were used to improve the toughness of bisphenol-A diglycidyl ether epoxy resin cured with p,p′-diaminodiphenyl sulphone. The hybrid modifiers were effective in toughening the epoxy resin. When using the modifier composed of 10 wt% PMS (M̄w 313000) and 2.5 wt% PMSH (2.5 mol% p-hydroxystyrene units, M̄w 316000), the fracture toughness (KIC) for the modified resins increased 100% with no deterioration in the flexural properties and the glass transition temperature. The improvement in toughness of the epoxy resins was attained because of the co-continuous phase structure and the improvement in interfacial adhesion. The toughening mechanism is discussed in terms of the morphological characteristics of the modified epoxy resin systems.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pi.1995.210380405
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  • 19
    Electronic Resource
    Electronic Resource
    Synthesis and properties of new tetrafunctional epoxy resins containing oxyethylene units (1990)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 41 (1990), S. 2301-2310 
    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: Tetraglycidyl ethers of 2,2′,2″,2‴[sulfonyl bis(4,1-phenylenenitrilo)] tetrakisethanol and 2,2′,2″,2‴[methylene bis(4,1-phenylenenitrilo)]tetrakisethanol were synthesized and characterized. Curing reactivities of these new epoxy resins are investigated by differential scanning analysis. The mechanical, thermal, and dynamic mechanical properties of these resins cured with p,p'-diaminodiphenylsulfone were examined and compared to those fo the conventional tetrafunctional epoxy resin (MY-720). These new epoxy resins have the advantages of being easier to handle, having higher curing reactivities, and giving cured resins with higher toughness, compared with MY-720 resin.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1990.070410932
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  • 20
    Electronic Resource
    Electronic Resource
    Modification of epoxy resins with poly(aryl ether ketone)s (1991)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 43 (1991), S. 1685-1692 
    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: Poly(aryl ether ketone)s were used as modifiers for bisphenol-A diglycidyl ether epoxy resin (AER 331) cured with methyl hexahydrophthalic anhydride. Poly(phthaloyl diphenyl ether) (PPDE), soluble in the uncured epoxy resin without using solvents, was prepared by the Friedel-Crafts reaction of phthaloyl chloride and diphenyl ether. The mechanical, thermal, and dynamic viscoelastic properties of the modified resins with PPDE were examined and compared to the parent resin (AER 331). The fracture toughness, KIC, for the modified resins increased at no expense to their mechanical and thermal properties on 10 wt % addition of PPDE with molecular weights of more than 17,000. The toughening mechanism is discussed based on the morphological and dynamic viscoelastic behaviors of the modified epoxy resin system.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1991.070430911
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