Expansion of expandable graphite is able to chop down a graphite flake into a worm-like structure containing thousands of losing individual layer with thickness between 50 to 150nm. In theory, this is equivalent to increase the effective concentration of the filler in multiplying the number which is approximately similar to the chopped down number. Therefore it would be very effective to enhance electrical and thermal conductivity, fire retardancy and some mechanical properties when used as filler in a polymer. In reality, it is difficult to separate those expanded layers in the worm structure during polymer melt processing, resulting in much lower efficiency in property enhancement. This study investigated the key problems causing such a situation in each processing step of the melt processing. It was identified that feeding stage was the key step to prevent effective exfoliation of the expanded structure. The expanded layers in the worm structure were easily compressed back to the original graphite structure when collision with polymer pellets. The data obtained by the quantachrome confirmed this finding. Solutions toward resolving the problem were also developed.