Advanced engineering resin and wood fiber composite

Abstract

The invention relates to a composition including an engineering resin and wood fiber composite that can be used in the form of a linear extrudate or thermoplastic pellet used to manufacture structural members. The resin/wood fiber composite structural members can be manufactured in an extrusion process or an injection molding process as a linear extrudate or pellet that can have a cross-section of any arbitrary shape, or can be a regular geometric shape and have a volume of at least about 12 mm.sup.3. Preferably the pellet is a right cylindrical pellet having a minimum radius of about 1.5 mm and a minimum length of 1 mm weighing at least 14 mg. The invention also relates to the environmentally sensitive recycle of waste streams. The resin/wood fiber composite can contain an intentional recycle of a waste stream including polymer flakes, polymer particles, or wood fiber as well as adhesives, paint, or preservatives. The initial mixing step before extrusion of the composite material insures substantial mixing and melt contact between molten resin and wood fiber. The extruded pellet includes a useful proportion of resin, wood fiber and water. During the extrusion, water is removed intentionally to dry the material to a maximum water content of less than about 10 wt % based on the pellet weight. The pellet is then introduced into an extruder or injection molding apparatus wherein the composite pellet material is shaped into a useful cross-section.

Dependencies are inferred from the claim text.