Dokument: Biobased Reactive Compounds in Novel & Sustainable Adhesive Systems
| Titel: | Biobased Reactive Compounds in Novel & Sustainable Adhesive Systems | |||||||
| URL für Lesezeichen: | https://docserv.uni-duesseldorf.de/servlets/DocumentServlet?id=65969 | |||||||
| URN (NBN): | urn:nbn:de:hbz:061-20240603-110539-0 | |||||||
| Kollektion: | Dissertationen | |||||||
| Sprache: | Englisch | |||||||
| Dokumententyp: | Wissenschaftliche Abschlussarbeiten » Dissertation | |||||||
| Medientyp: | Text | |||||||
| Autor: | Kropff, Marlo [Autor] | |||||||
| Dateien: |
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| Beitragende: | Prof. Dr. Hartmann, Laura [Gutachter] PD Dr. Schaper, Klaus [Gutachter] | |||||||
| Stichwörter: | Adhesives, Polymerization, Biorenewable | |||||||
| Dewey Dezimal-Klassifikation: | 500 Naturwissenschaften und Mathematik » 540 Chemie | |||||||
| Beschreibung: | Currently, the chemical and materials industry adapts processes towards a more circular economy due to challenges posed by climate change. Potential strategies for the adhesives industry deal with the incorporation of sustainable materials by using circular feedstocks to become independent from fossil fuels which enables the exploitation of novel molecules for new and exciting systems with unique properties. Furthermore, the development of long-lasting products has gained much attention by enabling recycling and repair solutions via debonding mechanisms. During recent years, academic and industrial research focuses more and more on evaluating advantages and drawbacks of novel adhesive systems with high renewable carbon content and debonding features. In this context, this thesis aims at the evaluation of vinyl ethers and 4-vinylphenol derivatives in adhesive systems. Both compound classes are already available from biobased resources to a certain extent.
Vinyl ethers possess a unique combination of properties that make them an attractive alternative for use in many industries, particularly those that are concerned with sustainability or environmentally friendly practices. One reason is the potential production from biobased sources from a variety of routes. Another is their extraordinarily high reactivity in living cationic polymerizations. A major objective of this thesis is to understand and subsequently control exothermic vinyl ether polymerization and therefore develop a pathway for their extended commercial use in industry. Cationic photopolymerization of small monomers results in intense heat generation and consequently a degradation of mechanical properties from deterioration on a molecular level. In this work, control of these drawbacks from exothermic behavior is demonstrated by the utilization of self-synthesized urethane-based prepolymers with vinyl ether functionality and by the subsequent addition of various filler materials. Moreover, the scope of vinyl ether curing was expanded by adding a moisture-driven post-curing step and by the utilization of thiols in thiol-ene polyaddition reactions. To investigate possible debonding-by-hydrolysis features in vinyl ether systems, hemiacetal ester prepolymers were synthesized and implemented. The impact on mechanical properties and the potentials and limitations of the resulting debonding capabilities were analyzed. In addition, comparative kinetic experiments were conducted to evaluate cationic polymerization of hemiacetal ester and urethane prepolymers. Finally, a prototype was developed by incorporating a 4-vinylphenol derivative, 4-methoxy styrene, with considerable adhesive performance and debonding features. In literature, polymerizable phenol derivatives have gained considerable attention for their use as high performance materials often conveniently available from waste streams. The ionic polymerizable 4-vinylphenol derivative sodium styrene sulfate was successfully synthesized. A degradation process over time was observed and elucidated in aging tests. The cationic and radical polymerization kinetics of tetrabutyl ammonium styrene sulfate were analyzed and compared to the common and structurally similar monomer styrene. The ionic character of styrene sulfate introduces exciting features in adhesive systems. In this work, tetrabutyl ammonium styrene sulfate was tested as a comonomer in two acrylate-based adhesive systems with radical curing mechanisms. Both approaches aimed at replacing inert ionic liquids, which may cause a decrease in cohesion, with the ionic comonomer in conductive materials. Thus, an increase in adhesive performance while maintaining ionic conductivity is expected. In the course of these experiments, the potential of styrene sulfate for electrochemical debonding systems was demonstrated as proof-of-concept. Moreover, the use of styrene sulfate in pressure sensitive adhesives results in an increase in adhesive performance and wetting acceleration. | |||||||
| Lizenz: |  Dieses Werk ist lizenziert unter einer Creative Commons Namensnennung 4.0 International Lizenz | |||||||
| Fachbereich / Einrichtung: | Mathematisch- Naturwissenschaftliche Fakultät » WE Chemie » Organische Chemie und Makromolekulare Chemie | |||||||
| Dokument erstellt am: | 03.06.2024 | |||||||
| Dateien geändert am: | 03.06.2024 | |||||||
| Promotionsantrag am: | 22.11.2023 | |||||||
| Datum der Promotion: | 26.03.2024 |
