Made of Pure Catalytic Material

All catalysts used in the wrapping technique described above belong to the first group. The beads are pure polymer, completely sulfonated. 

The low mechanical stability is caused by the large dimensions of the bodies prepared by Spes. To avoid this, Fuchigami decreased the size of the sintered bodies 

Chaplits prepared similar products in an extruder [8]. The main difference was that he extruded copolymers consisting of cross-linked polystyrene with a thermoplastic polymer. As a pore-forming agent water was used in the extrusion process. Acid sites are created by sulfonation of the cut extrudates. As an application, bbutanol production from water and isobutylene was suggested. 

Yoshioka prepared fibers with ion-exchange properties [9,10]. Polypropylene and polystyrene were melted and fibers produced. Then the fibers were cross-linked and functionalized by treatment with paraformaldehyde, acetic acid, and sulfuric acid. The fibers can be woven into fabrics that can be used in RD processes. 

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