Abstract: Provided are: a manufacturing method for polymer particles, including: mixing a polymer solution, which is obtained by dissolving a polymer in a good solvent, and a polymer non-solvent, which is a non-solvent for the polymer and has compatibility with the good solvent, in a continuous or intermittent manner; and allowing a mixed solution of the polymer solution and the polymer non-solvent to flow down through a tubular body provided substantially vertically, thereby completing the precipitation of polymer particles; and a manufacturing apparatus for polymer particles. The manufacturing method enables the manufacture of polymer particles which have a relatively narrow particle diameter distribution even when the polymer particles are kept in a dispersion solution state.

Abstract: A porous polyamide fine powder having been prepared by bringing a non-solvent B for the polyamide into contact with a polyamide solution in which a polyamide is dissolved in a solvent a and containing a remaining solvent A is treated with a poor solvent C which is compatible with the solvent A at least at a temperature of 40° C. or higher at a temperature of 40° C. or higher, whereby the solvent A is extracted out of the porous polyamide fine powder.

Abstract: A crystalline polymer exhibiting crystal transition in the solid phase state, which satisfies the relationship defined by the formula 150>?Htr>1.6Ttr?3.5 (1) (wherein ?Htr represents the endotherm (J/g) accompanying crystal transition and Ttr represents the crystal transition temperature (° C.)). This crystalline polymer has a weight average molecular weight of 600 thousand or less and a crystal transition temperature (Ttr) of 67° C. or below. Since this crystalline polymer has a low phase transition temperature, a high heat of a crystal transition, and a high melting point, the potential utility thereof as a switching element or a thermal storage material used at around normal environment temperatures (20 to 50° C.) is high.

Abstract: A conductive polymer composition comprising 100 parts by weight of a crystalline polymer (A) and 5 to 150 parts by weight of a conductive powder (B) dispersed in the crystalline polymer (A) is disclosed. The crystalline polymer (A) shows crystal transition, thereby the conductive polymer composition exhibits PTC characteristics.

Abstract: A conductive polymer composition comprising 100 parts by weight of a crystalline polymer (A) and 5 to 150 parts by weight of a conductive powder (B) dispersed in the crystalline polymer (A) is disclosed. The crystalline polymer (A) shows crystal transition, thereby the conductive polymer composition exhibits PTC characteristics.