prime polymer were melt kneaded at a cylinder temperature of 280 u00b0 c and a screw speed of 220 rpm by a twin screw extruder having a screw diameter of 45 mm manufactured by toshiba machine co ltd to form strand shaped gut the formed gut was cooled by a cooling bath and thereafter granulated by a cutter to obtain pellets the obtained pellets were molded at a barrel temperature of 280 u00b0 c by using an injection molding machine is100 manufactured by toshiba machine co ltd to obtain a molded product the results of evaluating the molded product by the above mentioned methods are shown in table 1 consequently it is confirmed that flame retardance of the molded product subject to injection molding is remarkably improved 3 by mass of a polyimide having an average particle diameter of 60 u03bcm and 97 by mass of aluminum hydroxide al oh 3 99 5 by mass na 2 o 0 25 by mass having an average particle diameter of 10 u03bcm were dry blended at 600 rpm for 1 minute by a henschel mixer 50 by mass of the blend and 50 by mass of a linear low density polyethylene lldpe trade name neozex2540r prime polymer were blended to obtain pellets in the same manner as in example 1 which obtained pellets were subject to injection molding to obtain a molded product the results of evaluating the molded product by the above mentioned methods are shown.