Multiple relaxation dynamics under electric field enables tunable viscoelastic response of poly(methyl methacrylate) above glass transition temperature.

This article focuses on the electro-viscoelastic behavior of poly(methyl methacrylate) (PMMA) above its glass transition temperature (Tg) under direct current (DC) electric fields. The study reveals that electric stimuli influence PMMA’s mechanical response by affecting chain relaxation dynamics at different length scales: local segmental polarization increases elastic and loss moduli and transient viscosity, while polarization-induced chain conformation changes at larger scales reduce the elastic modulus and modulus plateau. Rheological tests, including frequency sweeps, stress relaxation, and creep, demonstrate that electric fields enhance energy dissipation and accelerate polymer chain relaxation by weakening intermolecular constraints. These findings provide insights into tuning the viscoelastic properties of stimuli-responsive polymers through controlled electric fields.