By means of multiscale molecular simulation, we show that solvophilic–solvophobic AB diblock copolymer brushes in the semi-dilute regime present a re-entrant disorder/order/disorder transition. The latter is fully controllable through two parameters: the grafting density and the solvophobic to solvophilic ratio of the tethered macromolecules. Upon increasing density, chains first aggregate into patches, then further order into a crystalline phase and finally melt into a disordered phase. We demonstrate that the order/disorder transition can be explained through the peculiar properties of the aggregates: upon increasing density, the aggregation number grows as expected. On the contrary, their projection on the plane shrinks, thus melting the emergent ordered phase. Such a density dependent shrinkage, seen for the first time as the cause to an order/disorder phase transition, is as a consequence of the entropic/enthalpic competition that characterises the hierarchical self-assembly of the brush.
Capone, B., Likos, C.N., & Coluzza, I. (2021). Grafting density induced reentrant disorder–order–disorder transition in planar di-block copolymer brushes. SOFT MATTER [10.1039/D0SM02154G].
Titolo: | Grafting density induced reentrant disorder–order–disorder transition in planar di-block copolymer brushes | |
Autori: | ||
Data di pubblicazione: | 2021 | |
Rivista: | ||
Citazione: | Capone, B., Likos, C.N., & Coluzza, I. (2021). Grafting density induced reentrant disorder–order–disorder transition in planar di-block copolymer brushes. SOFT MATTER [10.1039/D0SM02154G]. | |
Abstract: | By means of multiscale molecular simulation, we show that solvophilic–solvophobic AB diblock copolymer brushes in the semi-dilute regime present a re-entrant disorder/order/disorder transition. The latter is fully controllable through two parameters: the grafting density and the solvophobic to solvophilic ratio of the tethered macromolecules. Upon increasing density, chains first aggregate into patches, then further order into a crystalline phase and finally melt into a disordered phase. We demonstrate that the order/disorder transition can be explained through the peculiar properties of the aggregates: upon increasing density, the aggregation number grows as expected. On the contrary, their projection on the plane shrinks, thus melting the emergent ordered phase. Such a density dependent shrinkage, seen for the first time as the cause to an order/disorder phase transition, is as a consequence of the entropic/enthalpic competition that characterises the hierarchical self-assembly of the brush. | |
Handle: | http://hdl.handle.net/11590/387510 | |
Appare nelle tipologie: | 1.1 Articolo in rivista |