Melt Processing of Bioplastic Composites via Twin Screw Extrusion and Injection Molding

Abstract

Polymer composites composed of polyhydroxybutyrates and natural fibers were extruded to investigate the effect of varying screw speed and lubricant loadings. Optical microscopy results show that increasing screw speed can enhance the dispersion of fibers within the polymer composite. At high screw speeds this caused an exothermic reaction to occur within the barrel resulting in the fibers thermally degrading. In terms of mechanical properties considerable increases in flexural properties were observed with the increase in screw speed. However, impact and tensile properties were negatively affected, due in part to the level of fiber attrition.

Keywords:

• Mechanical properties
• Natural fibers
• Polyhydroxybutyrate
• Screw speed
• Twin screw extrusion

Notes

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