Electromechanical polyaniline-cellulose hydrogels with high compressive strength

Usually, it is very difficult to fabricate hydrogels from hydrophobic polyaniline (PANI). In the present work, an electromechanical PANI-cellulose hydrogel, for the first time, was prepared from a PANI-cellulose transparent solution dissolved in a NaOH-urea aqueous system at low temperature by cross-linking with epichlorohydrin. The composite hydrogels displayed a homogeneous macroporous structure, good miscibility, and excellent mechanical strength, as a result of the association of the PANI chains with the cellulose crosslinked networks held together by noncovalent interactions. Moreover, the hydrogels exhibited a continuous and linear crawling motion under a low applied electric field. The motion of the composite hydrogels was an acceleration process, reflecting the characteristics of a rapid electrical response. This work shows the great potential of a smart hydrogel for applications in the field of biomimetic materials.