21.04.2021
16:00-16:30 EEST
15:00-15:30 CET
14:00-14:30 BST
Xiaomin Qian
Interdisciplinary Nanoscience
Center (iNANO),
Aarhus University, Denmark
20.04.2021
15:00-15:30 EEST
14:00-14:30 CET
13:00-13:30 BST
Alejandro J. Müller
University of the Basque Country UPV/EHU
IKERBASQUE, Basque Foundation for Science, Bilbao
Spain
Crystallization of isomorphic and isodimorphic random copolymers
Abstract: The crystallization of random copolymers depends on the chemical structure of the repeating units involved, molar ratio of comonomers and molecular weight1-5. When comonomers are very different from their chemical structure point of view, total exclusion of the second comonomer occurs and crystallization is restricted to weight fraction contents lower than approximately 30% or less. If on the other hand the repeating units are very similar, a single crystalline phase can form (i.e., isomorphism), see Figure 1, and Tm is a linear function of composition. Intermediate cases are very interesting because pseudo-eutectic behaviors are displayed, see Figure 1, and double crystalline copolymers can be obtained at eutectic compositions. In this invited talk, examples of the 3 cases schematized in Figure 1 will be presented derived from our recent works on copolyethers and copolyesters [1-5].
Figure 1. Schematic representation of the different Tm dependences on comonomer content for random copolymers (left). Cartoons of the models of the different crystallizations modes (right) described on the left: Isomorphism, comonomer exclusion and isodimorphism. (Figure modified from ref. 1).
1. Pérez-Camargo, R. A.; Arandia, I.; Safari, M.; Cavallo, D.; Lotti, N.; Soccio, M.; Müller, A. J. Europ. Polym. J., 2018, 101, 233–247 (and references therein).
2. Basterretxea, A.; Gabirondo, E.; Flores, I.; Etxeberria, A.; Gonzalez, A.; Müller, A. J.; Mecerreyes, D.; Coulembier, O.; Sardon, H. Macromolecules, 2019, 52, 3506−3515.
3. Flores, I.; Etxeberria, A.; Irusta, L.; Calafel, I.; Vega, J. F.; Martínez-Salazar, J.; Sardon, H.; Müller, A. J. ACS Sust. Chem. Eng., 2019, 7, 8647−8659.
4. Arandia, I.; Meabe, L.; Aranburu, N.; Sardon, H.; Mecerreyes, D.; Müller, A. J. Macromolecules, 2020, 53, 669−681
5. Safari, M.; Mugica, A.; Zubitur, M.; Martínez de Ilarduya, A.; Muñoz-Guerra, S.; Müller, A. J. Polymers, 2020, 12, 17, 1-21