TY  - THES
A1  - Zarafshani, Zoya
T1  - Chain-end functionalization and modification of polymers using modular chemical reactions
T1  - Ketten-Ende Funktionalisierung und Modifikation von Polymeren mittels modulare chemischen Reaktionen
N2  - Taking advantage of ATRP and using functionalized initiators, different functionalities were introduced in both α and ω chain-ends of synthetic polymers. These functionalized polymers could then go through modular synthetic pathways such as click cycloaddition (copper-catalyzed or copper-free) or amidation to couple synthetic polymers to other synthetic polymers, biomolecules or silica monoliths. Using this general strategy and designing these co/polymers so that they are thermoresponsive, yet bioinert and biocompatible with adjustable cloud point values (as it is the case in the present thesis), the whole generated system becomes "smart" and potentially applicable in different branches. The applications which were considered in the present thesis were in polymer post-functionalization (in situ functionalization of micellar aggregates with low and high molecular weight molecules), hydrophilic/hydrophobic tuning, chromatography and bioconjugation (enzyme thermoprecipitation and recovery, improvement of enzyme activity). Different α-functionalized co/polymers containing cholesterol moiety, aldehyde, t-Boc protected amine, TMS-protected alkyne and NHS-activated ester were designed and synthesized in this work.
N2  - In dieser Arbeit wurden mittels der ATRP Methode sowie durch Benutzung funktioneller Initiatoren verschiedene Funktionalitäten an der α- und ω-Position der synthetischen Polymere (Kettenenden) eingeführt. Diese funktionalisierten Polymere können durch modulare synthetische Methoden wie z.B. die “Klick-Zykloaddition” (kupferkatalysiert oder auch kupferfreie Methoden möglich), Amidierung mit anderen synthetischen Polymeren oder Biomolekülen, oder auch mit Silikatmonolithen gekuppelt werden. Den beschriebenen Strategien folgend und unter Benutzung von thermoresponsiven, bioinerten und biokompartiblen (Co-) Polymeren mit einstellbaren Trübungspunkten können mittels Temperaturänderungen leicht steuerbare, „smarte“ Polymersysteme für verschiedene Anwendungen hergestellt werden. Im Rahmen dieser Arbeit wurden speziell Anwendungen wie die Postfunktionalisierung (in situ Funktionalisierung mizellarer Aggregate mit Molekülen, die sowohl niedrige als auch höhere Molekulargewichte aufweisen), hydrophiles/hydrophobes Tuning von Polymeren, Chromatographie an Polymeren sowie Biokonjugation von Polymeren (Enzymthermoprezipitation und -Gewinnung, Enzymaktivitätsmodifizierung) genauer untersucht. Es wurden verschiedene α-funktionalisierte (Co-)Polymere, die Cholesterol, Aldehyde, t-Boc geschützte Amine, TMS-geschützte Alkine und NHS-aktivierte Ester entwickelt und hergestellt und mittels passender ATRP Initiatoren eingeführt.
KW  - Atom Transfer Radical Polymerization
KW  - Klick-Chemie
KW  - Biokonjugation
KW  - Funktionalisierung
KW  - Modifizierung von Polymeren
KW  - ATRP
KW  - Click chemistry
KW  - Bioconjugation
KW  - Functionalization
KW  - Polymer Modification
Y1  - 2012
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-59723
ER  - 
TY  - JOUR
A1  - Izraylit, Victor
A1  - Hommes-Schattmann, Paul J.
A1  - Neffe, Axel T.
A1  - Gould, Oliver E. C.
A1  - Lendlein, Andreas
T1  - Polyester urethane functionalizable through maleimide side-chains and cross-linkable by polylactide stereocomplexes
JF  - European polymer journal
N2  - Sustainable multifunctional alternatives to fossil-derived materials, which can be functionalized and are degradable, can be envisioned by combining naturally derived starting materials with an established polymer design concept. Modularity and chemical flexibility of polyester urethanes (PEU) enable the combination of segments bearing functionalizable moieties and the tailoring of the mechanical and thermal properties. In this work, a PEU multiblock structure was synthesized from naturally derived L-lysine diisocyanate ethyl ester (LDI), poly(L-lactide) diol (PLLA) and N-(2,3-dihydroxypropyl)-maleimide (MID) in a one-step reaction. A maleimide side-chain (MID) provided a reactive site for the catalyst-free coupling of thiols shown for L-cysteine with a yield of 94%. Physical cross-links were generated by blending the PEU with poly(D-lactide) (PDLA), upon which the PLLA segments of the PEU and the PDLA formed stereocomplexes. Stereocomplexation occurred spontaneously during solution casting and was investigated with WAXS and DSC. Stereocomplex crystallites were observed in the blends, while isotactic PLA crystallization was not observed. The presented material platform with tailorable mechanical properties by blending is of specific interest for engineering biointerfaces of implants or carrier systems for bioactive molecules.
KW  - Functionalization
KW  - Polylactide stereocomplex
KW  - Biomolecules coupling
Y1  - 2020
U6  - https://doi.org/10.1016/j.eurpolymj.2020.109916
SN  - 0014-3057
SN  - 1873-1945
VL  - 137
PB  - Elsevier
CY  - Oxford
ER  -