Veröffentlichungen 2023
Highlights 2023
Transparent, thermoplastic, aliphatic polyesters through crystallization under molecular confinement
Maziar Matloubi, Melika Sarem, Barbara Heck, Günter Reiter, and V. Prasad Shastri. Matter 6 (2023) 3057–3074
In semi-crystalline biodegradable polymers, uncontrolled evolution of crystallinity impacts processing and bulk properties, limiting their application. Through molecular confinement of low-molecular-weight poly(L-lactic acid) (PLLA) segments by polysiloxane blocks and processing at far-from-equilibrium conditions, PLLA crystallization into lamellae of a few nm in thickness with coherence lengths below 100 nm was achieved, thus giving access to films that are optically transparent for over 5 years, possess high Young’s modulus and elongation at break, undergo controlled degradation, and support functional endothelialization. The films possess a nanophase segregated bulk morphology with a hydrophobic siloxane-dominated surface that can be pressure bonded following cold oxygen plasma activation and low-temperature glassy PLLA domains interspersed by nanoscale crystalline physical crosslinks that enable glass transition temperature-triggered shape change. The segmented thermoplastic polyesters (STEPs) can additionally be processed using melt-extrusion printing into 3D objects, thus opening potential application opportunities in the fabrication of implantable/degradable electronics, smart textiles, and packaging. (more...)
Brahim Bessif, Barbara Heck, Thomas Pfohl, Cuong Minh Quoc Le, Abraham Chemtob, Valentina Pirela, Justine Elgoyhen, Radmila Tomovska, Alejandro Müller, Günter Reiter. Macromolecules 56 (2023) 1461–1470
We present investigations of the intricate crystallization and melting behavior of an alternating copolymer synthesized by photopolymerization of 2,2’dimercaptodiethyl sulfide (DMDS) with di(ethylene glycol)divinyl ether (DVE). Upon increasing temperature, we observed the succession of two distinctly separated melting processes, which we related to the sequential formation and disappearance of two crystalline polymorphs. Due to their well separated melting temperatures and, we labelled these polymorphs as LOW--form and HIGH--form, respectively. X-ray diffraction results confirmed differences in the parameters of the crystal unit cells. (more...)
Emna Khechine, Sebastian Noack, Helmut Schlaad, Jun Xu, Günter Reiter, Renate Reiter. Langmuir 39 (2023) 2710–2718
We investigated changes in the hydration state of poly(ethylene glycol) through morphological changes in Langmuir monolayers of a poly(ethylene glycol)-poly(L-lactide) (PEG-b-PLLA) diblock copolymer. When the PEG blocks were hydrated, we observed a remarkable morphology of bundles of ring-like filaments, arranged concentrically, yielding densely packed disk-like objects with a hollow centre. We attribute the uniform curvature of these filaments to a strong mismatch between the molecular volumes occupied by PLLA blocks and hydrated PEG blocks, respectively. (more...)
Gesamtliste 2023
- Identifying a Mesomorphic Boundary Zone within Polybutene-1 Single Crystals Emerging during a Crystal-Crystal Transformation
- Jinlong Chen, Binghua Wang, Changyu Shen, Jingbo Chen, Günter Reiter, Bin Zhang. Macromolecules 56 (2023) 5050–5057
- Determining the maximum melting temperature of polymer crystals from a change in morphology of dewetting rims
- Gang Wang, Guotao Shi, Anchenyi Yang, Binghua Wang, Changyu Shen, Jingbo Chen, Günter Reiter, Bin Zhang. Polymer 274 (2023) 125874
- Unraveling the complex polymorphic crystallization behavior of the alternating copolymer DMDS-alt-DVE
- Valentina Pirela, Justine Elgoyhen, Radmila Tomovska, Jaime Martin Perez, Cuong Minh Quoc Le, Abraham Chemtob, Brahim Bessif, Barbara Heck, Günter Reiter, and Alejandro Müller. ACS Appl. Polym. Mater. 5 (2023) 5260–5269
- Nucleation Assisted through the Memory of a Polymer Melt: A Different Polymorph Emerging from the Melt of another One
- Brahim Bessif, Barbara Heck, Thomas Pfohl, Cuong Minh Quoc Le, Abraham Chemtob, Valentina Pirela, Justine Elgoyhen, Radmila Tomovska, Alejandro Müller, Günter Reiter. Macromolecules 56 (2023) 1461–1470
- Tuning the hydraulic resistance by swelling-induced buckling of membranes in high-aspect-ratio microfluidic devices
- Claas-Hendrik Stamp, Binyam Solomon, Friederike Lang, Efstathios Mitropoulos and Thomas Pfohl. Lab Chip 23 (2023) 3662-3670
- Reversible Dehydration-Hydration of Poly(ethylene glycol) in Langmuir Monolayers of a Diblock Copolymer Inferred from Changes in Filament Curvature
- Emna Khechine, Sebastian Noack, Helmut Schlaad, Jun Xu, Günter Reiter, Renate Reiter. Langmuir 39 (2023) 2710–2718
- Transparent, thermoplastic, aliphatic polyesters through crystallization under molecular confinement
- Maziar Matloubi, Melika Sarema, Barbara Heck, Günter Reiter and V. Prasad Shastri. Matter 6 (2023) 3057-3074