Wood-plastic composites utilizing ionomer capstocks and methods of manufacture

摘要

An extruded composite adapted for use as a building material includes a core having a base polymer and a natural fiber in a substantially homogeneous mixture and an ionomer capstock. To improve adherence of the ionomer to a base polymer, the ionomer can be mixed with a similar or substantially similar base polymer prior to coextrusion with the core. Additionally, various additives may be mixed with the capstock material to improve visual aesthetics of the product and performance of the building material, especially over time.

主权项

1. A coextruded composite profile adapted for use as a building material, the coextruded composite profile comprising:
a wood-plastic composite core comprising a base polymer and a natural fiber in a mixture; and a capstock layer disposed over at least a portion of the wood-plastic composite core, the capstock layer comprising an ionomer and a capstock polymer different from the ionomer in a mixture, wherein (i) the base polymer and the capstock polymer each is selected from the group consisting of polypropylene, polyethylene, and combinations thereof, (ii) the capstock polymer is present in the capstock layer in an amount between 72.5% and about 99%, by weight, and (iii) the capstock layer is characterized by an absence of natural fiber.