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  • 1
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 28 (1990), S. 1361-1376 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The thermal decomposition of a series of four saturated and unsaturated C4 polyoxalates shows competing modes of depolymerization, fragmentation to polyenes and CO2, and crosslinking. These decompositions, which were studied by DSC and TGA, and intensively by EI- and CI-MS, could be rationalized in terms of the structure of the alcohol portions of the polyesters. The polymers were synthesized by ester interchange, which gave materials with DP values of 5-32.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: N,N-diallylaniline monomer was prepared in good yields, for use in preparation of homopolymer and for copolymerization with acrylamide. Functionalized N,N-diallylaniline monomer, as sodium N,N-diallylsulfanilate, was also prepared in good yields for copolymerization with acrylamide. Both monomers were fully characterized by elemental analysis, IR, and NMR. Poly (N,N-diallylaniline) was obtained by polymerization of a strongly acidic aqueous solution of N,N-diallylaniline initiated with hydrogen peroxide. Spectroscopic data from this homopolymer was used to facilitate spectral assignments of the new copolymers. Copolymers of acrylamide with N,N-diallylamine were prepared at monomer feed ratios of 10, 20, and 30 mol % amine and gave 3.5, 7.4, and 8.9 mol % incorporation, respectively. Similar diallyl monomer incorporation rates were obtained for the copolymerization of sodium N,N-diallylsulfanilate with acrylamide. With 10, 30, and 50 mol % of the sodium salt relative to acrylamide, 3.9, 8.4, and 19.2 mol % incorporation of the diallyl monomer was obtained.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 33 (1995), S. 1209-1217 
    ISSN: 0887-624X
    Keywords: polyethylene ; functionalization ; transesterification ; surface ; fluorescence ; kinetics ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The effects of solvent on the accessibility and reactivity of an ester-bound fluorophore at a functionalized polyethylene-solvent interface have been studied. Fluorophore-labeled polyethylene surfaces were prepared by blending together a small amount of a pyrene esterterminated ethylene oligomer and a host linear low density polyethylene in solution. Films cast from such solutions were then studied by fluorescence spectroscopy to show that a significant number of the entrapped pyrene groups were at the polyethylene-solvent interface and capable of reaction with soluble reagents. Subsequently, transesterification of these ester-bound pyrenes using various sodium alkoxides in alcohol, alcohol-toluene, or alcohol-tetrahydrofuran solvent mixtures was studied by fluorescence and UV-visible spectroscopic analysis of the supernatant. The extent of alcoholysis of such esters was found to be significantly affected by the solvent chosen and by the structure of the alcohol. © 1995 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 27 (1989), S. 4205-4226 
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthetic procedures for preparation of terminally functionalized linear ethylene oligomers are described. The preferred synthetic method is anionic oligomerization of ethylene with n-butyllithium-tetramethylethylenediamine and electrophilic substitution of the living oligomer so-formed. Conditions and procedures for subsequent chemistry to elaborate the end groups of these oligomers are described. These procedures afford strictly linear ethylene oligomers which contain a wide variety of end groups and which range in molecular weight from 1000 to 4500 (Mn). The product oligomers were characterized spectroscopically as toluene-d8 solutions at 110°C using multinuclear NMR, FT-IR, fluorescence, and UV-visible spectroscopies as appropriate. Alternative stepwise approaches to such oligomers are also discussed.
    Additional Material: 1 Tab.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Sodium N-(4-sulfophenyl) maleimide (SPMI) and its saturated succinimide counterpart were first prepared according to established methods. Hydrolysis experiments on these monomers monitored by 1H-NMR showed that although SPMI monomer was about 15% hydrolyzed in D2O at 23°C in 24 h. Sodium N-(4-sulfophenyl) succinimide, which is similar in structure to the imide units in the copolymers, was only 1% hydrolyzed after 18 days at 23°C and 29% hydrolyzed after 18 days at 60°C. This indicated that the saturated imide rings in the copolymer might be sufficiently stable to hydrolysis for the copolymers to be useful. However, hydrolysis at high pH demonstrated that the imide rings would be rapidly saponified under alkaline conditions, destroying the structural rigidity that the intact rings might have provided in the copolymer chains. Sodium N-(4-sulfophenyl) maleimide (SPMI) was copolymerized with acrylamide in water at 30°C without cleavage of the imide ring. Water-soluble poly [acrylamide-co-sodium-N-(4-sulfophenyl) maleimide] (PAMSM) samples containing from 7.4 to 64 mol % imide were prepared. Photoacoustic FTIR and 13C-NMR spectra were used to confirm the structure of the copolymers obtained. Elemental analysis was used to determine the imide content of the copolymers, and from this composition data reactivity ratios were calculated for the two component monomers.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 0887-624X
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The comonomer required, p-maleimidobenzoic acid (MBA) was first prepared in good yield by refinements of published methods. p-Carboxysuccinanilic acid (CSA), and p-succinimidobenzoic acid (SBA), were also prepared to provide models useful for IR and NMR for spectroscopic assignments of the new copolymers. Polymerization of MBA with acrylamide in glacial acetic acid at 60°C gave copolymers with estimated viscosity average molecular weights of 60,000 to 90,000. Yields and viscosity average molecular weights decreased as the MBA to acrylamide monomer feed ratio was increased. The rate of incorporation of MBA into the copolymer rose from 7 to 23% when the mole ratio in the feed was raised from 5 to 20%. Decreasing the initiator concentration increased molecular weights by less than predicted and reduced the yield of copolymer for any given feed ratio of MBA to acrylamide. In all cases about 30-40% of the MBA units in the purified copolymers were hydrolyzed. A change to dimethyl sulfoxide solvent gave good, and poor yields of copolymer at 5 and 10 mol % MBA, respectively, and no copolymer at 20 mol % MBA. Viscosity average molecular weights of the copolymer products prepared in DMSO were somewhat lower than obtained for the copolymers prepared in acetic acid. Polymerization in a DMSO-water mixture gave a negligible yield of polymeric product. Instead, only hydrolysates of MBA precipitated when the coloured polymerization solutions were added to methanol.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 389-396 
    ISSN: 0887-624X
    Keywords: polyethylene ; polypropylene ; oxidation ; biodegradation ; C—H bond activation ; functionalization ; XPS ; ATR-IR ; surface ; Gif ; oxidase ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Modification of polyethylene and polypropylene film and powder surfaces with oxygen and hydrogen peroxide is promoted by nonporphyrinic, nonfree radical based iron reagents such as Fe3O(OCOCH3)6(C6H5N)3.5 and FeCl3 • 6H2O/picolinic acid. These oxidation systems introduced small amounts of carbonyl groups onto the surface of these hydrocarbon polymers. The most visible manifestation of this reaction was increased polyolefin wettability toward water. IR spectroscopy, XPS spectroscopy, and chemical derivatization all were used to verify that the reaction had occurred and that a chemically derivatizable surface had been prepared. The overall process produced a fraction of the density of functional groups introduced by conventional etching chemistry.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 2049-2053 
    ISSN: 0887-624X
    Keywords: polyethylene ; grafting ; polymerization ; surface ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
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  • 9
    ISSN: 0887-624X
    Keywords: polyurethanes ; benzoquinones ; amine-quinones ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The amine-quinone monomer, 2,5-bis(N-2-hydroxyethyl-N-methylamino)-1,4-benzoqui-none (AQM-1), was prepared by the multiple-step condensation of 2-(N-methylam-ino)ethanol with benzoquinone in the presence of oxygen. This crystalline monomer was used to prepare a series of amine-quinone polyurethanes by condensation polymerization, either in the melt or in solution (THF or DMF), with a diisocyanate (MDI, TDI, or IPDI) and an oligomeric diol [poly(caprolactone) or poly(1,2-butylene glycol)]. The amine-quinone functional group was stable under the polymerization conditions, and was incorporated into the main chain, giving red-brown polyurethanes that had molecular weights in the range of 11,000-90,000 and were soluble in THF, MEK, DMF, and DMSO. The thermal properties were consistent with a two-phase morphology with an amorphous soft segment, containing the oligomeric diol, and a microcrystalline hard segment, containing AQM-1. The polymers having a low hard segment content (〈50%) were rubbery (soft segment Tg 〈-25°C); polymers having a high hard segment content (〉50%) were thermoplastic (hard segment Tg〉150°C). © 1995 John Wiley & Sons, Inc.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 0959-8103
    Keywords: kaolin ; steric stabilisation ; poly(ethylene oxide) ; poly(propylene oxide) ; grafting ; urethane ; 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 polymer-modified surface of kaolin was studied to determine the effect of changing the molecular weight of the polymer chain grafted on the surface. The particle was modified by attaching poly(ethylene oxide) to the surface using a urethane linkage.Upper critical flocculation temperature and contact angle measurements were conducted to quantify the changes in surface characteristics and stability in an aqueous dispersion. The effect of pH on stability and grafted density of polymer chains showed the mechanism of stabilisation to be that of enhanced steric stabilisation.The kaolin particle was also modified with the more hydrophobic poly(propylene oxide). The behaviour was characterised as for poly(ethylene oxide) and interesting differences in extent and mechanism for stabilisation were observed.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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