REINFORCING HIGH-DENSITY POLYETHYLENE WITH CELLULOSIC FIBERS .1. THE EFFECT OF ADDITIVES ON FIBER DISPERSION AND MECHANICAL-PROPERTIES

High density polyethylene (HDPE) was reinforced with 0-40 wt% of wood flour (aspen). The effects of: stearic acid, mineral oil, maleated polyethylene wax, and sodium silicate on the tensile and impact strength of the composite were studied. The comparison of tensile properties of the composites showed that the addition of maleated polyethylene wax produced a significant increase in tensile strength, with the increase in filler concentration, while the tensile modulus remained relatively unaffected. Microscopic studies of the composites indicate a better dispersion of the fibers in the polymer matrix when stearic acid was used.