Extrusion method and die achieving synergistic effect of ultrasonic vibration and uniform tensile stress

Abstract

The invention discloses an extrusion method and die achieving the synergistic effect of ultrasonic vibration and uniform tensile stress. The extrusion die comprises a die body, a first ultrasonic vibration device and a second ultrasonic vibration device. The first ultrasonic vibration device and the second ultrasonic vibration device each mainly comprise an amplitude-change rod, a vibration transmission rod, a transducer, a signal line and an ultrasonic generator; through holes are symmetrically formed in the die body; the small ends of the amplitude-change rods of the first ultrasonic vibration device and the second ultrasonic vibration device communicate with a die runner through the through holes; and the amplitude-change rods extend into the through holes of the extrusion die in the mode of being perpendicular to flanges. Through the extrusion process that ultrasonic vibration is perpendicularly overlapped on a melt, the pressure action of pulse change acts on the melt, and the synergistic effect of ultrasonic vibration and uniform tensile stress is achieved. According to the extrusion method and die, the pressure fluctuation during extrusion of the plastic melt is reduced, the apparent viscosity of the melt is reduced, the compatibility of polymer blends is improved, the flow uniformity of materials is improved, and thus the combination property of a finished product is improved.

Description

technical field [0001] The invention relates to a polymer material extrusion molding, in particular to a polymer material extruded product molding processing method and a die in which ultrasonic vibration and uniform tensile stress act synergistically. Background technique [0002] Extruded products account for more than half of the total plastic products, and all extruded products need to be processed through extrusion dies to achieve the molding properties of polymer materials. The extrusion die is not only an important part of the extrusion production line, but also has an important impact on the performance of the extruded product. At present, in most extrusion dies, the melt is mainly subjected to shear stress, or due to the local convergence / divergence of the flow channel section, it is subjected to transient tensile stress. The shear deformation can easily cause local high temperature and make polymer materials The molecular chain is broken to reduce the macroscopic ...

AI Technical Summary

Problems solved by technology

However, due to the low shear laminar flow mixing efficiency and poor mixing effect under the same deformation rate, the uniformity of the blend melt after the ultrasonic vibration is assisted is affected, and the further improvement of the ultrasonic vibration effect is restricted.

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