Die Swell Reduction

Li et al. [103] studied the die swell behaviors of PS, EPDM, and PS/EPDM (80/20) by using a special ultrasonic oscillation extrusion system developed in their laboratory. These authors investigated the effects of ultrasonic intensity and screw speed on die pressure, volume flow rate and apparent viscosity of polymers, as well as die swell. During extrusion, the apparent viscosities of the blends depended not 

In contrast, high-power or low-frequency ultrasound can be used to compatibi-lize immiscible polymer pairs by the high shear and degradation of the polymer chains. Moreover, in many cases there was no deterioration in mechanical properties, despite a lowering of both the molecular weight and viscosity. Dramatic improvements in the weld line strength of immiscible PS/HDPE blends were 

and Lee, J.W. (2007) Effect of ultrasound on the properties of biodegradable polymer blends of poly (lactic acid) with poly(butylene adipate-co-terephthalate). Macromd. Res., 15, 44-50. 

2 Hong, I.-K. and Lee, S. (2013) Properties of ultrasound-assisted blends of poly (ethylene terephthalate) with polycarbonate. J. Ind. Eng. Chem., 19, 87-93. 

3 Choi, M., Kim, Y, Kim, J., and Kim, H. (2008) Rheological properties and thermal degradation behaviors of sonochemically treated polycarbonate/polysiloxane blends. Kor.-Aust. Rhed. J., 20, 

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