Density functional study of one- and two-component bottlebrush molecules in solvents of varying quality

Abstract

Modified inhomogeneous statistical associating fluid theory (iSAFT) density functional theory is extended to bottlebrush polymers in both good and poor solvent. The detailed structures of side chains in the implicit solvent are calculated and have a semi-quantitative agreement with simulation. The average brush heights calculated from the theory agree with well-established scaling theories. iSAFT is easily extended to model bottlebrush polymers with two or more components. For an amphiphilic core-shell bottlebrush polymer, if the solvent-phobic block is much shorter than the solvent-philic block, it will fold towards the backbone even though it resides at the free end of the side chain. Similarly, for an amphiphilic mixed-type bottlebrush polymer, the chain length of different components has a great impact on the structure and properties of the molecule. The molecule may not have the response (the switch of outer layer) towards the solvent treatment if one component is significantly longer than the other. Our results provide insight into the conformation of bottlebrush polymers as well as guidance in practical applications.

GRAPHICAL ABSTRACT

Keywords:

• Bottlebrush polymer models
• density functional theory
• computer simulations
• interface phenomenon

Acknowledgments

We thank the Robert A. Welch Foundation (Grant No. C-1241) for financial support.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Correction Statement

This article has been republished with minor changes. These changes do not impact the academic content of the article.

Additional information

Funding

We thank the Robert A. Welch Foundation (grant number C-1241) for financial support.