Process for producing polymer alloy, polymer alloy, and molded article

A process of producing a polymer alloy comprising melt-kneading at least two incompatible crystalline resins in a supercooled state by chaotic mixing with a twin-screw extruder wherein the chaotic mixing is chaotic mixing in which, according to the particle tracking method, a logarithm of extension of an imaginary line (In L/L0), wherein L is a lineal length, and L0 is an initial lineal length, is not less than 2 and the supercooled state is a state in which a kneading temperature in a region from a polymer melting zone to a die-head is set at a temperature at least 75° C. higher than the glass transition temperature of a resin having a highest glass transition temperature among the crystalline resins used in the process of producing the polymer alloy, and set at a temperature 10° to 70° C. lower than the melting point of a resin having a highest melting point among the crystalline resins used in the process of producing the polymer alloy and wherein the resins are melted even at a temperature of 10 to 70° C. lower than the melting point of the resin having a highest melting point among the crystalline resins used in the process of producing the polymer alloy.