Process for making an electroconductive polymer composition

Claim 1

A process for making an electroconductive shaped article from at least two polymers which are incompatible with each other, such that they do not form a single phase upon mixing, and an electroconductivity-imparting filler which is in the form of at least one of a powder, a flake and a short fiber and is at least one member selected from the group consisting of a carbonaceous filler, a metallic filler, and a filler surface-coated with carbon or metal, which comprises the steps of: kneading a mixture of the polymers together with 3 to 50% by weight, based on the total weight of the polymers, of the filler to prepare a polymer composition wherein the filler is distributed predominantly in one of the polymers which has a higher affinity for the filler and has a continuous or substantially continuous phase; and shaping the polymer composition into a shaped article, said mixture of the polymers showing crystallization peaks or second-order transitions attributable to the respective mixed polymers when the mixture is subjected to differential scanning calorimetric measurement or dynamic visco-elasticity measurement, and said mixture of polymers having a composition such that the extraction ratio of the polymer having a higher affinity for the filler is at least 0.3, said extraction ratio being expressed by the following formula: extraction ratio=A/B wherein A is the amount of the polymer having a higher affinity for the filler, which has been extracted from the polymer mixture by a solvent capable of dissolving only the polymer having a higher affinity for the filler, and B is the amount of the polymer having a higher affinity for the filler in the polymer mixture before extraction.