In-situ Fabrication of Functional Materials inside Porous Fiber using Microwave Selective Heating.

We developed a simple fabrication method, which can emplace functional materials inside porous fibers. In contrast to conventional impregnation methods or surface coating, various functions can be included inside of natural or synthetic fibers. This fabrication method has three steps. First, the raw material solution is absorbed to the fiber. Then the fiber is immersed and pressurized in immiscible liquids with the raw material solution. Finally, the functional particles are fabricated in-situ inside of the fiber by a chemical reaction such as microwave selective heating. As a model reaction, we fabricated silver-nanoparticle-containing cotton fiber. The elemental silver was distributed inside of the fiber in a cross-sectional distribution as confirmed by SEM-EDS. Furthermore, we fabricated fibers with zeolite particles inside of porous PTFE fibers.