PURPOSE: To obtain the titled composition, having improved electric conductivity and suitable for electronic apparatuses, by incorporating specific bundled metal fibers in polymerizing an aromatic vinyl compound or further with a vinyl compound in an aqueous medium.

CONSTITUTION: (A) 100pts.wt. total of (A1) 100W50wt% vinyl compound, e.g. styrene, and (A2) 0W50wt% another vinyl compound, e.g. acrylonitrile, in the total amount or partially incorporated in 200W2,000pts.wt. aqueous medium and polymerized. When the polymerization conversion reaches 5W60wt%, 5W500 pts.wt. bundled metal fibers obtained by collecting 300W20,000 metal fibers having 2W20μm diameter and 1W15mm length, e.g. stainless steel fibers, etc., with a water-insoluble resin, e.g. ethylene-vinyl acetate resin, etc., and the residual vinyl compound is incorporated to carry out subsequent polymerization.