Development of electroactive silicate nanocomposites prepared for use as ionic polymer-metal composites (IPMC's) artificial muscles and sensors

Nanocomposites are a new class of composites, which are typically nanoparticle-filled polymers. One promising kind of nanocomposite is clay-based and polymer-layered silicates nanocomposites because the starting clay materials are naturally abundant and, also, their intercalation chemistry is well understood at the present time. A certain clay, Montmorillonite (M_xAl_4-xMg_x)Si₈O₂₀(OH) ₄, has two-dimensional layers of their crystal structure lattice where the layer thickness is around 1 nm with the lateral dimension of approximately 30 nm to a few microns. These layers organize themselves to form stacks, so-called the "Gallery," through a van der Walls gap in between them. In this work, Montmorillonite (MMT) was modified by a cationic surfactant so as to lower its surface energy significantly. Such a process gave rise to favorable intercalation of nanoparticles within the galleries. The obtained XRD patterns and TEM images indicate that the silicate layers are completely and uniformly dispersed (nearly "exfoliated") in a continuous polymer matrix of Nafion™ that has been successfully used as the starting material of ionic polymer-metal composites (IPMC's).