Impact of Doping on the Mechanical Properties of Conjugated Polymers

Molecular dopants are widely used to modulate the electrical properties of conjugated polymers. This talk will explore how doping alters their mechanical properties. In particular, polythiophenes with oligoethylene glycol side chains will be discussed, which feature a low elastic modulus in the MPa range. Molecular doping can alter both the glass transition temperature and degree of crystalline order, resulting in a much stiffer material with an elastic modulus of more than 200 MPa. Strategies are explored that permit to decouple the effect of doping on the electrical and mechanical properties.