Structural and dynamic properties of poly(styrene-co-maleic anhydride) at the interface of conjugated polymers

Conjugated polymers are employed in a variety of application areas due to their bright fluorescence and strong biocompatability. For these applications, readily fabricated conjugated polymer nanoparticles (CPNs) are formed using capping agents to provide stable and soluble conjugated polymer formulations. Post-assembly functional modification and chemical doping can be used to further tune CPN properties for target applications.

The nanoscale structure of conjugated polymer materials emerges from interactions between different molecules, and holds significant control over their much-prized optical properties. Reliably controlling the optical properties of conjugated polymers upon aggregation and assembly remains a challenge. The structural properties of the interface between the capping agents and the conjugated polymer play a key role in the ability to then functionalise the surface of the conjugated polymer formulation with any specific molecules required for tuning the delivery of a CPN to a desired target. In this presentation, I will present the results of a series of all-atom molecular dynamics simulations that we have conducted in order to provide a molecular scale understanding of the structural and dynamic properties of poly(styrene-co-maleic anhydride) (PSMA), which is a common capping agents for CPNs, on the interface of the conjugated polymer, poly(9,9-di-n-octylfluorene-alt-benzothiadiazole) (F8BT). I will compare the properties of the PSMA capped interface with those which are found when using another commonly used capping agent, Brij O10. Finally I will discuss the effect of the difference in the interfaces formed on the functionalisation of these polymer interfaces.