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doi:10.22028/D291-29992
Dateien zu diesem Datensatz:
Datei | Beschreibung | Größe | Format | |
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Dissertation Sandra Schaefer_UdS2019.pdf | Kumulative Dissertation mit Supporting Informations | 38,74 MB | Adobe PDF | Öffnen/Anzeigen |
Titel: | Self-Healing Polymer-based Nanocomposites using the Diels-Alder-reaction: Studies on the Influence of Composition on Self-Healing Properties |
VerfasserIn: | Schäfer, Sandra |
Sprache: | Englisch |
Erscheinungsjahr: | 2018 |
DDC-Sachgruppe: | 540 Chemie |
Dokumenttyp: | Dissertation |
Abstract: | SiO2-nanoparticle-polymer–interfaces were tested according to their suitability as a DA - reversible crosslinking site. The role of the chemical composition of the polymer matrix was shown. Cuts of several millimeters could be healed within the siloxane-based nanocomposite, after reconnection of cut surfaces with the help of chloroform, by the DA reaction. The limit of interface-reactivity was investigated in a cofunctionalization study. Therefore, FexOy nanoparticles were functionalized with a monolayer DA-alkyl phosphonic acids. A drastic drop in conversion was recorded, when the attacking reagents were dodecyl derivatives of maleimide and furan instead of maleimide/methylfuran. This result indicates, that due to the sterical situation created by the attacking reagent on the surface only a minimal conversion with polymer chains is possible Therefore, diene and dienophile were distributed statistically within the matrix, instead of being located cumulative at the particle surface. Linear one-component polymers, consisting of diene, dienophile and one additional hydrogen bonding motive were synthesized using controlled radical polymerization techniques. Urea-group bearing spherosilicates were synthesized in high yields. By blending these both components, a hybrid material with double intrinsically reversible networks was received. The H bonds reconnect cut interfaces at 30°C, whereafter cuts in the mm-scale could be healed by the DA reaction. |
Link zu diesem Datensatz: | urn:nbn:de:bsz:291--ds-299923 hdl:20.500.11880/28474 http://dx.doi.org/10.22028/D291-29992 |
Erstgutachter: | Kickelbick, Guido |
Tag der mündlichen Prüfung: | 5-Mär-2019 |
Datum des Eintrags: | 13-Dez-2019 |
Fakultät: | NT - Naturwissenschaftlich- Technische Fakultät |
Fachrichtung: | NT - Chemie |
Sammlung: | SciDok - Der Wissenschaftsserver der Universität des Saarlandes |
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