Cellulose electro-active paper fabricated by facile solvent exchange pretreatment and its physical and electromechanical properties

The cellulose electro-active paper (EAPap) has been discovered as a smart material that can be used for sensors, actuators and flexible electronics. EAPap is made from regenerated cellulose that requires dissolving cellulose pulp using solvents with a heating process. However the heating process in dissolving cellulose is very critical to the performance of EAPap. In this paper, we introduce a new fabrication process of cellulose EAPap with a pretreatment process of cellulose, which simplifies the fabrication process and does not require the heating process. The pretreatment process includes the first immersion of cellulose into deionized water and the second immersion it into N,N-dimethylacetamide (DMAc) solvent, followed by twice repeat of the immersions. The pretreated cellulose was dissolved using lithium chloride (LiCl)/DMAc solvent without heating, which gives a cellulose solution. The pretreated cellulose solution was compared with another cellulose solution made with the LiCl/DMAc solvent and a heating process in terms of viscosity and solubility. Cellulose EAPap samples were made by using two cellulose solutions and their physical and electromechanical properties were compared in terms of transparency, ion concentration, surface morphology, Young's modulus, dielectric constant and piezoelectric charge constant. The pretreatment of cellulose results in similar or better physical properties of EAPap, which simplifies the cellulose EAPap fabrication.