Organic semiconductors, particularly π-conjugated polymers and small molecules, enable the development of deformable, stretchable and flexible electronics due to a plethora of factors including their tunable redox, optical, electronic and mechanical properties. However, an informed understanding of how multi-scale morphological characteristics of the polymeric and molecular semiconductors influence bulk properties that contribute to electronic and optical performance, especially under operational thermal and mechanical stresses, remains incomplete. 

This lack of understanding poses a challenge to scalability and commercialization of organic electronics. This dissertation develops and deploys computational modeling approaches, particularly atomistic molecular dynamics (MD) simulations, to investigate the multiscale morphological behavior of these synthetic semiconducting materials in the context of thermomechanical stability. Electron-donating π-conjugated polymers and electron-accepting small molecules — systems that are used in combination to develop bulk heterojunction (BHJ) organic semiconductors — are modeled as their neat phases and as blends to elucidate expectations regarding their thermomechanical behavior as they traverse operational thermal and mechanical processes. 

By systematically modeling these organic semiconductors over time and length scales that approach experiments, this dissertation fits into the larger quest for how local (or long-range) molecular morphology, beginning from molecular structural compositions, dictate thermomechanical behavior, thus providing valuable design and processing principles in the bid for electronically efficient, mechanically robust and manufacture-scale organic electronics.