Self‐Assembled Nanofibers from Random Silicate Platelets

Abstract

Fibrous materials of lengths up to 10 μm are obtained from the self‐assembly of random silicate platelets. Under transmission electron microscopy electron‐beam bombardment, a fiber of stacked platelets was further transformed into a tube‐like arrangement (see Figure), conceptually shown in the inset.

Manipulating Assemblies of High‐Aspect‐Ratio Clays and Fatty Amine Salts to Form Surfaces Exhibiting a Lotus Effect

“…The formation of a ribbonlike network is attributed to the self-aligning ability of the high-aspect-ratio NSP components, as reported previously. [27] The photographs shown in the insets of Figure 2a-d illustrate the correlation between the contact angle and the surface roughness as observed by SEM. By varying the ratios of the constituents of the SMA3000-D400H + /NSP/ n-C 18 H 37 NH 3 + formulations, different degrees of roughness are obtained for the generated surfaces, which in turn can be correlated to the hydrophobicity of the surfaces.…”

“…Because of the presence of strong electrostatic attractions, the platelets exhibit a strong tendency to self-align into ordered structures. [27] Here, we demonstrate the manipulation of these thin platelets by the introduction of ionic bonding with fatty alkyl organics, thus modifying the self-assembly process to form a superhydrophobic surface. The surface roughness has been directly observed by scanning electron microscopy (SEM), field-emission SEM (FESEM), and dynamic force mode atomic force microscopy (DFM-AFM).…”

“…Previously, we have reported that the platelet structures can undergo a unique self-aggregation process to form long stacks. [26,27] However, upon the attachment of alkyl organics, the modified NSPs self-assemble in a different manner, yielding a "rough" superhydrophobic surface. Experimentally, the aggregation of NSPs on a glass surface is induced by homogeneously mixing the platelets with n-octadecylammonium chloride (n-C 18 H 37 NH 3 + Cl -) in an aqueous suspension, spin-coating the suspension onto a glass surface, and drying at 80°C in an oven for 4 h. The thickness of the coating is estimated to be approximately 100 lm.…”

“…[19][20][21] Various geometric shapes, such as nanospheres, nanofibers, nanorings, and nanotubes, have been obtained by self-assembly. [22][23][24][25][26][27] Naturally abundant smectite clays such as montmorillonite are well characterized as layered structures consisting of highaspect-ratio silicate platelets bound together in primary stacks by electrostatic interactions. [28][29][30][31] A newly developed process has enabled the delamination of the layered structures, yielding discrete platelets in aqueous suspension.…”

Elongational Rheology of Polymer/Clay Dispersions: Determination of Orientational Extent in Elongational Flow Processes

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] Highly ordered polymer nanocomposites are complex materials that display a rich morphological behavior because of variations in composition, structure and properties on a nanometer length scale. [6,14,15] Novel physical properties of polymer/clay nanocomposite multilayered films are strongly dependent on the structure and orientation of precursor nanocomposite dispersions and gels.…”