Filter‐Through Method of Making Highly Efficient Polymer‐Clay Nanocomposite Membranes

Abstract

AbstractElectrospun filter with hierarchical pore structure and variable pore diameter is used for the first time in making a flexible, strong, and high gas‐barrier membrane. A versatile, technical, benign processing method for the fabrication of highly filled (>25 wt%) efficient gas‐barrier polymer membrane with perfectly aligned synthetic high‐aspect ratio layered silicate (clay) of variable and considerable thickness (up to 5 µm) is presented. This process combines advantageous features of an electrospun substrate like high porosity, variable pore size (typically <5 µm), thermoplasticity and of an aqueous suspension of a synthetic clay consisting of single 1 nm thick layers with a huge median lateral extension (>10 µm) in a layered structure. By simple and fast filtration, a gas‐barrier self‐assembled layer of variable and appropriate thickness is obtained on a mechanically stable thermoplastic electrospun filter support that subsequently can be laminated adhesively or via hot pressing, even in a multilayer structure, if required. The resulting composite membranes are flexible, strong, transparent, and show enhanced gas‐barrier properties.