An injection molded housing for a portable electronic device is provided. The housing contains a thermoplastic composition that includes a polyarylene sulfide melt processed in the presence of a disulfide compound and a filler. Without intending to be limited by theory, it is believed that the disulfide can undergo a chain scission reaction with the starting polyarylene sulfide to lower its melt viscosity, which can lead to decreased attrition of the filler and thus improved mechanical properties. Due to this ability to reduce viscosity during melt processing, the present inventors have discovered that relatively high molecular weight polyarylene sulfides can be fed to the extruder with little difficulty.