Jump to main content
Jump to site search

Issue 48, 2019
Previous Article Next Article

Modeling of the photo-induced stress in azobenzene polymers by combining theory and computer simulations

Author affiliations

Abstract

It has been shown recently that the photo-induced deformations in azobenzene-containing polymers of a side-chain architecture can be explained by means of the so-called orientational approach. The explanation is based on the following sequence of steps: (i) reorientation of azobenzenes under illumination, (ii) reorientation of the polymer backbones coupled mechanically to azobenzenes, and (iii) development of large stress in a material. Step (i) is based on the angle selective absorption of the azobenzene chromophore, which is a well established fact. Step (iii) has been validated in a series of recent theoretic studies in an infinite coupling limit. Concerning step (ii), in a real material, the backbone–azobenzene coupling will be always finite, resulting in a decrease of the effective torque sensed by the backbones and in a time delay in their reorientation. To study the relevance of these effects in detail, we perform coarse-grained molecular dynamics simulations of side-chain azobenzene-containing oligomers in bulk at conditions close to the glassy state. The focus is on the dynamical properties of such a system and on its response to the illumination, with the latter modeled either as an orientation potential applied to the azobenzenes or via their stochastic photo-isomerization. By matching the amount of light-induced stress evaluated in both cases, we obtained the equivalent orientation potential as a function of the illumination intensity and the system density.

Graphical abstract: Modeling of the photo-induced stress in azobenzene polymers by combining theory and computer simulations

Back to tab navigation

Publication details

The article was received on 13 Sep 2019, accepted on 13 Nov 2019 and first published on 15 Nov 2019


Article type: Paper
DOI: 10.1039/C9SM01853K
Soft Matter, 2019,15, 9894-9908

  •   Request permissions

    Modeling of the photo-induced stress in azobenzene polymers by combining theory and computer simulations

    J. M. Ilnytskyi, V. Toshchevikov and M. Saphiannikova, Soft Matter, 2019, 15, 9894
    DOI: 10.1039/C9SM01853K

Search articles by author

Spotlight

Advertisements