Role of inherent polarization and ion transport in the actuation of cellulose based EAPap

The application of electroactive polymer devices requires the availability of their properties at various operating conditions. This in turn necessitates a structure-property relationship based on an in-depth understanding of the underlying mechanism responsible for their strain-field response. Cellulose-based Electro-Active Paper (EAPap) has been studied as an attractive EAP material for artificial muscles due to its low cost, availability, lightweight, large displacement output, low actuation voltage and low power consumption. The understanding of the actuation mechanism of this material is important in order to improve the performance and also to better target the application. So far, based on the structure and processing of cellulose-based EAPap, it is believed that two actuation mechanisms are possible: ion transport and dipolar orientation. To physically investigate the actuation mechanism of EAPap, several tests are performed. X-ray diffractogram study exhibits that EAPaps have more amorphous parts than raw cellulose fibers, and there is some possibility of structural change during activation. NMR study shows that the cellulose paper is an ordered structure. TSC current showed a linear relationship with poling electric field, indicating dipolar orientation. . Impedance analysis of EAPap showed an evidence of ionic migration effect. Thus, we conclude that there can be piezoelectric effect and ionic migration effect at the same time associated with dipole moment of cellulose paper ingredients. The amount of these effects may be depending on environmental condition. Quantitative investigation of these two effects on EAPap should be followed with environmental condition.