To investigate the influence of the pellet starve feeding condition on the continuous plastication process with PP (hot cut pellet), in this study, visualization analysis was performed and plastication mechanism under the pellet starve feeding condition was revealed. It was confirmed that both the pellet gathering point and the melting start point under the starve feeding process relatively moved to the downstream region along the screw compared to one under the pellet flood feeding, and also this phenomenon was encouraged by increase in the starvation ratio and the screw rotation rate. Also confirmed that although the melting completion point in a low screw rotation rate was located almost at same point as one under the flood feeding, the melting did not complete in a high screw rotation rate accompanied with generation of solid bed break-up.
 According to the results, the following plastication process under the starve feeding condition was suggested. The resin pellets are transported with a low filling density through the upstream region of the feed zone, to aggregate in the downstream region while they are heat-receiving and rolling. When the pellets those surfaces are heated at the compression zone have been integrated by aggregation, they enclose a high temperature interface between each of them. Hence the melting completes in a short period of time without any obvious generation of the melt pool（MP）. Although the pellets are molten efficiently in a low screw rotation rate under the starve feeding condition, increase in the screw rotation rate results in a delay in the plastication process, and it can lead to poor melt failure and generation of the solid bed (SB) break-up(BUP).

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