Melt Rheological Behavior of High Density Polyethylene/Poly(Vinyl Alcohol) Fiber Composites Prepared via Melt Compounding Method

Abstract

In this work, high density polyethylene (HDPE)/poly(vinyl alcohol) (PVA) fiber composites have been fabricated via melt compounding by employing a twin-screw extruder. The resulted composites samples of four different PVA fiber loadings (i.e. 0, 5, 10, and 20 wt%) were then characterized using an oscillatory rheometer to investigate the effect of PVA loadings on their melt rheological behavior (e.g. storage modulus, loss modulus, complex viscosity). Additionally, the surface morphology of cryo-fractured surface of the composites were also investigated by using a scanning electron microscopy (SEM). The SEM micrographs showed that PVA fibers were perfectly embedded and well blended in HDPE matrix. Additionally, the melt rheological analysis results showed that the complex viscosity of all nanocomposites samples (i.e. PVAC-5, PVAC-10, and PVAC-20) were higher than that of neat PP (i.e. PVAC-0) and increased with the increase of nanoclay concentrations. Moreover, to further study the relationship between the PVA fiber loadings and complex viscosity of the composites, a well-known Carreau-Yasuda equation was employed to model the complex viscosity data from the rheological test. It was found that the equation fitted well the rheological test data.