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Aggregation and Solubility of a Model Conjugated Donor-Acceptor Polymer.

ABSTRACT: In conjugated polymers, solution-phase structure and aggregation exert a strong influence on device morphology and performance, making understanding solubility crucial for rational design. Using atomistic molecular dynamics (MD) and free-energy sampling algorithms, we examine the aggregation and solubility of the polymer PTB7, studying how side-chain structure can be modified to control aggregation. We demonstrate that free-energy sampling can be used to effectively screen polymer solubility in a variety of solvents but that solubility parameters derived from MD are not predictive. We then study the aggregation of variants of PTB7 including those with linear (octyl), branched (2-ethylhexyl), and cleaved (methyl) side chains, in a selection of explicit solvents and additives. Energetic analysis demonstrates that while side chains do disrupt polymer backbone stacking, solvent exclusion is a critical factor controlling polymer solubility.

SUBMITTER: Reid DR

PROVIDER: S-EPMC6260830 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Aggregation and Solubility of a Model Conjugated Donor-Acceptor Polymer.

Reid Daniel R DR Jackson Nicholas E NE Bourque Alexander J AJ Snyder Chad R CR Jones Ronald L RL de Pablo Juan J JJ

The journal of physical chemistry letters 20180809 16

In conjugated polymers, solution-phase structure and aggregation exert a strong influence on device morphology and performance, making understanding solubility crucial for rational design. Using atomistic molecular dynamics (MD) and free-energy sampling algorithms, we examine the aggregation and solubility of the polymer PTB7, studying how side-chain structure can be modified to control aggregation. We demonstrate that free-energy sampling can be used to effectively screen polymer solubility in ...[more]

PMID: 30063357

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