Effects of Several Ingredient Variables on Mechanical Properties of Wood Fiber-Polyolefin Composites Blended in a Thermokinetic Mixer

Abstract

AbstractWe examined the influence of several variables on the mechanical properties of wood fiber-polyolefin composites blended in a thermokinetic mixer. A pure cellulose fiber and fibers from old newspaper provided similar performance in matrices of virgin polypropylene or recycled milk bottles (high density polyethylene). Relative to wood flour, these fibrous fillers led to greater strength and modulus with both plastics, to lower impact energy with polyethylene, and to similar impact energy with polypropylene. Compared with the existing commercial wood flour-polypropylene system, the totally recycled polyethylene-newspaper composite provided equivalent strength and modulus, along with greater notched impact energy. Little difference was seen in composites containing a maleated polypropylene additive in the form of the solid anhydride or the emulsified potassium salt, indicating that the additive acted as a dispersing agent and not as a strong coupling agent.