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  • 1
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 13 (1969), S. 1845-1858 
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Mercaptan and disulfide contents of modified cotton fabrics could be determined by application of Leach's polarographic method for wool, with minor modification.It was found that mercaptocellulose prepared by the reaction of tosyl cellulose and potassium thiolacetate followed by alkaline hydrolysis contained considerable amounts of disulfided in addition to mercaptain. Iodometric titration of mercaptocellulose gave a higher value of mercaptan than that obtained by the polarographic method. The mercaptan and disulfide contents and methylene blue uptake of the iodine-treated samples indicate that some of the mercaptan groups further undergo oxidation to acidic groups as a result of the iodine treatment.The spatial effect in the oxidation of mercapto groups in modified cotton is briefly discussed.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 2
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 16 (1972), S. 1495-1503 
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Reactions of tosylated cotton with potassium thiolacetate followed by alkaline hydrolysis yielded products containing both mercaptan and disulfide. The proportion of disulfide in the products depended much on the solvent used for the thiolacetylation. Reactions of tosylcellulose with thiolacetate in various solvents were investigated by polarographic and infrared analyses. Part of the acetylthio groups produced in acetone or in dimethylformamide was found to undergo rearrangement to form mercaptocellulose acetate. On the other hand, acetylthio groups formed in methanol were found to undergo complete methanolysis to form mercaptocellulose, and most of the mercapto groups thus produced were oxidized before hydrolysis treatment to yield the corresponding disulfide. This could account for the high disulfide proportion in the sample obtained through the reaction of tosylcellulose in methanol. Reaction of tosylcellulose with sodium thiosulfate yielded cellulose disulfide without mercaptan formation.
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 3
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 14 (1970), S. 865-878 
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: Bis-β-isocyanatoethyl disulfide (BIED) was synthesized from diethyl dithiodipropionate and its reaction with cotton in dimethylformamide was investigated. The sulfur content of the treated cotton decreased by reduction with tri-n-butylphosphine. The polarographic and infrared analyses revealed that BIED reacted with cotton both monofunctionally and bifunctionally to form branches and crosslinks, respectively. The ratio of the crosslinks to the total amount of BIED combined increased in general as the reaction progressed. X-Ray study indicated that the reaction took place mainly in the original amorphous region.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 4
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The reaction of methyl iodide with cellulose β-mercaptoethylaminocarboxylate (RDTC) made from cotton was investigated. The product was found to contain dimethyl sulfonium groups in addition to S-methyl groups, with accompanying hydrolytic cleavage of some of urethane linkages. The iodide counterions could be easily exchanged with hydroxide and chloride ions. The dyeabilty of RDTC and its sulfonium derivatives toward Direct Sky Blue A was studied. The equilibrium uptake of the dye by RDTC decreased with increasing sulfur content, while the uptake by the sulfonium derivatives was higher than that of control cotton and increased with increasing sulfonium content. The counterions did not affect the dyeability. The dye adsorbed onto the sulfonium derivatives was very fast against solvent extraction, and could be extracted only with Cadoxen containing 0.5% sodium hydroxide. The equilibrium uptake of the dye was much more than the amount calculated on basis of the 1 : 1 ionic bonding between the sulfonic acid group in the dye molecule and the sulfonium group in the modified cotton. The spatial effect in the dye-sulfonium bonding is discussed.
    Zusätzliches Material: 1 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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  • 5
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 99 (1966), S. 232-242 
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: Die Copolymerisation von Tetrahydrofuran (THF) mit Diketen (DK) bei 0°C mit einem Triäthylaluminium/Wasser-System als Initiator, führt zu schwach gelben, festen Produkten. Der Nachweis fär eine Copolymerisation wurde durch IR-Analyse der benzolunlöslichen Fraktion erbracht; hierbei wurden Banden gefanden, die kristallinem Poly-THF zuzuordnen sind. Außerdem liefert die alkalische Hydrolyse dieser Fraktion homopolymere Tetrahydrofurane mit Molekulargewichten zwischen 1500 und 3100; sie besitzen OH- und COOH-Endgruppen. Diese experimentellen Befunde bestätigen die Annahme, daß es sich hier um Block-Copolymere und nicht um statische Copolymere handelt.
    Notizen: Copylymerization of tetrahydrofuran (THF) with diketene (DK) was carried out at O°C. using the triethylaluminum/water-system as catalyst. The produced polymer was a yellow solid. The formation of a copolymer was shown by the existence of THF units in the benzene-insoluble fraction of the polymeric product. The IR-spectrum of the benzeneinsoluble fraction had a band which can be ascribed to the crystalline poly-THF. Furthermore poly-THF having molecular weights of 1,500 to 3,100 was isolated from the hydrolyzed mixture of the benzene-insoluble fraction high yield; it has OH- and COOH-end groups. These facts have been taken to assume that the copolymerization of THF with DK leads to the formation of block copolymers instead of random copolymers.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
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