Dissertation Defense: Jenna Sartucci
Candidate Name: Jenna Sartucci
Major: Chemistry
Advisor: Nagarjuna Gavvalapalli, Ph.D.
Title: From Pendant Chains to π-Face Blocking Straps: Enhancing the Role of Side-Chains in Controlling Mechanical and Optical Properties of π-Conjugated Polymers
This dissertation is a body of research focusing on conjugated polymers and small molecules for organic electronics. The projects in this work are aimed at understanding the interplay between structure and function, towards the goal of generating conjugated polymers and small molecules with specially designed, novel architectures. First, a functionalized polythiophene derivative is used to generate ionically cross-linked π- conjugated polymer ionic networks. The size and strength of the ionic head group on the cross-linker is investigated to determine the effects of interaction strength on rheological and mechanical properties. The polymer ionic networks are mechanically robust, exhibiting viscoelastic properties and the potential to self-heal. The ordering and lamellar packing typical of polythiophenes remained intact in these polymer ionic networks, demonstrating the potential for this system to be used in flexible and self-healable
electronics.
While traditional conjugated polymers contain side chains to impart solubility, some projects in this work investigate the use of non-traditional pendant groups to impeded π-π stacking in certain directions. The aim here is to control the donor/acceptor interaction in charge transfer complexes, similar to those seen in organic solar cells and doped semiconductors. By blocking the π-face with a bifacial pendant group, we hypothesize that the location and orientation of donor/acceptor interactions can be tuned. Tuning the π-π interactions can have significant impact on the lifetime of charge separated states, reducing the likelihood of charge recombination and therefore improving device performance