Deformation on segment-structure of electrostrictive polyurethane/polyaniline blends

- Polymer blend is one of interest for improved electromechanical properties.
- Combinations of polyurethane and polyaniline were fabricated by solution casting.
- The permittivity and segment-structure are the main factors affecting with the electrostrictive ability.
- The obtained film that has a higher permittivity and larger hard-segment can enhance the electrostrictive coefficient.

Blends of elastic polyurethane (PU) and conductive polyaniline (PANI) were assessed for such improved electromechanical properties that are promising for further application in actuators, sensors and energy conversion. For the experiments, electrostrictive polyurethane blends were prepared with varied PANI contents. These blends were prepared with two alternative solvents, namely N,N-dimethylformamide (DMF) and 1-methyl-2-pyrrolidone (NMP), and were fabricated by solution casting. The morphology along with electrical and mechanical properties, and specifically the electrostrictive coefficient were studied. The electrostrictive behavior was determined from electric field induced strain, observed with a photonic displacement apparatus in the film thickness direction. The results suggest that the PANI component in NMP solvent effectively enhanced the electrostriction of these PU/PANI polymer blends. The solvent effects during film forming on the film's electrostriction were likely related to the hard interfacial domains between the dispersed PANI and the PU matrix that could increase the electrostriction coefficient.