Vinyl acetate-modified microcrystalline cellulose-reinforced HDPE composites prepared by twin-screw extrusion

In order to compare the effects of microcrystalline cellulose (MCC) as a filler, MCC and high-density polyethylene (HDPE) composites were produced with 4 different wt.% MCC loadings (1 wt.%, 5 wt.%, 10 wt.%, and 20 wt.%). To improve the compatibility between MCC and the matrix, MCC was acetylated with vinyl acetate (VA), and 2 different MCC-HDPE composites were produced with 5 wt.% and 10 wt.% VA-modified MCC loadings. Untreated MCC and VA-modified MCC-reinforced HDPE pellets were produced by using a twin-screw extruder. The MCC-HDPE composites were then compression-molded and the mechanical properties of the composites were determined. The thermal and morphological properties of the MCC-HDPE composites were characterized by using thermogravimetric and electron microscopy techniques, respectively. The VA-modified MCC-filled HDPE had a significantly higher tensile strength than the unmodified MCC-filled or the neat HDPE composites. The thermal stability of MCC was also improved with VA modification.