A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

A composite fiber composed of at least a metal sintered body and a ceramic sintered body. In the composite fiber, the metal sintered body and the ceramic sintered body are adjacent to each other. The composite fiber having the metal sintered body and the ceramic sintered body can have a tensile strength of 5 kgf/mm.sup.2 or more.

A composite fiber composed of at least a metal sintered body and a ceramic sintered body. In the composite fiber, the metal sintered body and the ceramic sintered body are adjacent to each other. The composite fiber having the metal sintered body and the ceramic sintered body can have a tensile strength of 5 kgf/mm.sup.2 or more.

A composite fiber having a core sheath-structure that includes a core portion having an electrically conductive material, and a sheath portion having a ceramic component covering the core portion. The composite fiber is constructed such that, when the core portion is connected to a ground, the sheath portion exhibits one of a positive surface potential or a negative surface potential over an entire surface of the sheath portion.

A composite fiber having a core sheath-structure that includes a core portion having an electrically conductive material, and a sheath portion having a ceramic component covering the core portion. The composite fiber is constructed such that, when the core portion is connected to a ground, the sheath portion exhibits one of a positive surface potential or a negative surface potential over an entire surface of the sheath portion.

A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

A polymer body includes a first thermoplastic polymer, and a second thermoplastic polymer. The first thermoplastic polymer and the second thermoplastic polymer form a continuous solid structure. The first thermoplastic polymer forms an external supporting structure that at least partially envelops the second thermoplastic polymer. A first flow temperature of the first thermoplastic polymer is at least 10° C. higher than a second flow temperature of the second thermoplastic polymer. The first thermoplastic polymer may be removable by exposure to a selective solvent.

Natural polymer-based fibrous elements including a modified polymer derived from a natural polymer and a surfactant, method for making such natural polymer-based fibrous elements and methods for making such fibrous structures are provided.

The present invention provides: a fibrous carbon characterized in that the average effective fiber length is 1-100 μm, and the crystallite length (La) measured using X-ray diffraction is 100-500 nm; an electrode mixture layer for a non-aqueous-electrolyte secondary cell, said mixture comprising an electrode active material and a carbon-based electroconductive auxiliary agent containing said fibrous carbon; an electrode for a non-aqueous-electrolyte secondary cell, the electrode comprising a collector and said electrode mixture layer for a non-aqueous-electrolyte secondary cell, the electrode mixture layer being laminated on the collector; and a non-aqueous-electrolyte secondary cell having said electrode for a non-aqueous-electrolyte secondary cell.