Effects of Fiber Type and Manufacturing Process on the Mechanical Properties of Natural Fiber Composite Fiberboard

ECOR, a product of Noble Environmental Technologies, is a sustainable alternative to tradition wood panels and fiberboard products. ECOR panels are made by hot pressing wet fiber pulp of urban and agricultural fibers, such as recycled corrugated cardboard, recycled office paper, kenaf core fibers, oat, or a mix of cardboard with one alternate fiber. This project studies the performance of raw (RA) panels, which are as-manufactured without resin coating, and high performance (HP) panels. HP panels were made by applying Entropy SuperSap resin in varying viscosity mixes to panels that had been desiccated at 150°C (302°F) for 30 min. Variations on resin application methodology and curing conditions were tested, but none resulted in full infusion of resin through the panel thickness. Tensile and short beam shear tests were performed on specimens of varying fiber content and panel density. Tensile and shear strengths of raw panels were found to increase roughly linearly with density. More highly processed urban fiber panels such as corrugated cardboard and office paper showed stronger properties than the less processed and often stiffer, lignin-coated agricultural fiber panels, such as kenaf and oat. The strength of HP panels increases compared to their RA counterparts but the amount of increase levels off with increasing density, possibly limited by the strength of the resin itself. The application of lower viscosity resin results in higher strength HP panels than resins with higher viscosity, suggesting more effective infusion of the lower viscosity resin into the voids of the fiber panel