Abstract: Vane extruder is novel plasticizing equipment based on elongational flow. During the polymer processing, the materials usually suffered shear stress, however dispersive mixing is achieved more efficiently contrast under shear flow field. Through analyzing the structural features of the vane extruder, the physical model is got, then the elongational deformation rate of the melt conveying process theoretically is got. It is found that the elongational deformation rate changes differently in the process of the angle changing from 0 to /2 and the angle changing from /2 to . At the former processing, the axial elongational deformation rate and circumference extensional rate have the same formula. The elongational deformation rate presents a parabola change as angle, it increased with the increase of eccentricity distance and rotating speed, and increased with the decrease of the inner radius of plate. The latter processing, it has the similar result. The elongational deformation rate presents attenuation as angle, it increased with the increase of eccentricity distance and rotating speed, and increased with the decrease of the inner radius of plate. Thus elongational deformation rate can be improved by increasing the eccentricity decreasing inner radius of plate as well as increasing rotating speed.

Key words: Elongational deformation rate, Melt conveying, Vane extruder