Veröffentlichungen 2022-2024
Highlights
In situ dissolution and swelling of confined lamellar polymer crystals through exposure to humid air
Brahim Bessif, Thomas Pfohl, Barbara Heck, Yaser Alshetwi, Emna Khechine, Jun Xu, and Günter Reiter. Macromolecules 55, 6015–6022, 2022
Induced by exposure to humid air, we observed in-situ the temporal and spatial changes in thickness and morphology of sandwich-like polymer platelets of a block copolymer. These micron-size platelets consisted of a crystalline poly(ethylene oxide) (PEO) lamella confined between two glassy poly(styrene) (PS) layers, formed via crystallization of a hydrophobic-hydrophilic PS-b-PEO diblock copolymer. We observed first the dissolution of the confined crystalline PEO layers characterized by sharp dissolution front propagating at a constant velocity as described by case II diffusion of a liquid into a solid. (mehr...)
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...)
Da Huang, Thorsten Hugel, and Günter Reiter. Macromolecules 2024, 57, 3696–3705
We have investigated the formation of millimeter-long filaments induced by spin-coating ca. 130 °C dilute para-xylene solutions of rapidly crystallizable polyethylene chains with a contour length in the micrometer range onto ca. 80 °C mica substrates. These filaments were radially oriented and accumulated on the periphery of the substrate. Our observations can be explained by the stretching of polymers through the flow field induced by spinning the solution on a solid substrate. The corresponding loss in conformational entropy emphasized attractive interactions between polymers, which resulted in the formation of bundles and their assembly into long filaments. (more...)
Gesamtliste
- Semi-crystalline poly(thioether) prepared by visible-light-induced organocatalyzed thiol-ene polymerization in emulsion
- Cuong Minh Quoc Le, Gautier Schrodj, Ibrahima Ndao, Brahim Bessif, Barbara Heck, Thomas Pfohl, Günter Reiter, Justine Elgoyen, Radmila Tomovaska and Abraham Chemtob. Macromol. Rapid Commun. 43 (2022) 2100740
- Primary nucleation in metastable solutions of poly(3-hexylthiophene)
- Tianyu Wu, Sivasurender Chandran, Yao Zhang, Tianze Zheng, Thomas Pfohl, Jun Xu, Günter Reiter. Macromolecules 55 (2022) 3325–3334
- An investigation on the heat dissipation in Zn-substituted magnetite nanoparticles, coated with citric acid and pluronic F127 for hyperthermia application
- Sara Shatooti, Morteza Mozaffari, Günter Reiter, Diana Zahn, Silvio Dutz. Physica B: Physics of Condensed Matter 625 (2022) 41346856
- 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
- Non-equilibrium Properties of Thin Polymer Films
- Sivasurender Chandran, Günter Reiter. In Matyjaszewski et al. (Eds.): Macromolecular Engineering: From Precise Synthesis to Macroscopic Materials and Applications, 4 Volumes, 2nd ed. Edition, Wiley-VCH Verlag GmbH, 2022. ISBN 9783527344550