Abstract
Bottlebrush polymers have a versatile architecture that is highly customizable due to the combination of a linear backbone and side chains. As a result of the chemical tethering of the side chains, both parts cannot be easily be separated. Huge effort is seen regarding the dynamical behavior of the side chains or the entire bottlebrush polymer, whereas few studies are available considering the backbone. Here, isotopic labeling in combination with quasi-elastic neutron scattering was used to compare the dynamical behavior of the bottlebrush’s backbone with the side chain dynamics. Keeping the side chains deuterated, (h-PNB)-g-(d-PPO), leads to the scattering signal dominated by backbone dynamics, while the fully protonated sample, (h-PNB)-g-(h-PPO), gives side chain dynamics. Both results reveal slower dynamics associated with the backbone with less heterogeneity, as seen for the side chains. Additionally, a plasticizer effect for the backbone dynamics is confirmed by extracting the glass transition temperature and comparing it with pure linear PNB.
| Original language | English |
|---|---|
| Pages (from-to) | 11180-11191 |
| Number of pages | 12 |
| Journal | Macromolecules |
| Volume | 58 |
| Issue number | 20 |
| DOIs | |
| State | Published - Oct 9 2025 |
Funding
The reported research was funded by the U.S. Department of Energy (DoE) under Grant DE-SC0019050. A portion of this research used resources at the High Flux Isotope Reactor and Spallation Neutron Source, a DOE Office of Science User Facility operated by the Oak Ridge National Laboratory. The beamtime was allocated to EQ-SANS on proposal number IPTS-36204. We would like to acknowledge Dr. William T. Heller for his support during the neutron beamtime. Experiments at the ISIS Neutron and Muon Source were supported by beamtime allocation RB2310062 from the Science and Technology Facilities Council. Data is available here: 10.5286/ISIS.E.RB2310062 . Mass spectrometry experiments were performed at the LSU Mass Spectrometry Facility (MSF). The Bruker UltrafleXtreme MALDI instrument was supported by NIH (Grant 1S10RR024520-01A1).