Tri-excluded WUCS glass fiber reinforced plastic composite articles and methods for making such articles

Abstract

Disclosed are a series of composite polymer composite structures formed by the coextrusion of at least two distinct polymeric components. A first polymeric component includes a structural composition and a second polymeric component includes a coating composition. The primary structural frame formed from the structural composition includes at least one longitudinal recess. These recesses may be filled with a third polymeric composition that may include wood byproducts and/or a blowing agent. The first polymeric component may include reinforcing fibers at least partially coated with a size composition that includes a film forming agent, a lubricant, one or more additives, and first and second coupling agents. The additives may be chosen to achieve selective or desired properties in the end product. The inclusion of additives to the reinforcing fiber enhances the fiber reinforcements and enables the production of reinforced composite articles having a desired combination of size, strength, appearance, and/or functionality.

Description

CROSS REFERENCE TO RELATED APPLICATIONS [0001] This application is a Continuation-in-Part of U.S. patent application Ser. No. 11 / 311,749 entitled “Tri-Extruded WUCS Glass Fiber Reinforced Plastic Composite Articles And Methods For Making Such Articles” filed Dec. 19, 2005, the entire content of which is expressly incorporated herein by reference in its entirety.TECHNICAL FIELD AND INDUSTRIAL APPLICABILITY OF THE INVENTION [0002] The present invention relates to tri-extruded composite articles, and more particularly, to a sizing composition for reinforcing fibers used in tri-extruded reinforced composite articles where the sizing composition includes additives to achieve desired physical or structural attributes. BACKGROUND OF THE INVENTION [0003] Wood fibers, especially fibers from waste wood generated during the production of dimensional lumber or the milling or shaping of wood substrates, in combination with one or more polymeric adhesives, have long been used in the production of...

AI Technical Summary

Benefits of technology

[0015] It is an advantage of the present invention that the inclusion of additives to the size composition permits for the customization of product-specific sizing compositions tailored to achieve desired physical or structural attributes.

[0016] It is another advantage of the present invention that utilizing the reinforcing fibers as a carrier for desired additives may result in an overall improvement in the performance of the products formed from the additive-sized reinforcement fibers.

[0017] It is yet another advantage of the present invention that incorporating additives into the size composition and onto the reinforcement fibers may aid the dispersion of the additives substantially evenly throughout the polymer matrix.

[0018] It is a further advantage of the present invention that by applying desired additives directly to the reinforcement fibers, the additives can be expected to more effectively enhance the interface between the resin and the surface of the reinforcement fibers.

[0019] It is also an advantage of the invention that because the additives are added with the size composition directly onto the reinforcement fiber, they may be incorporated at a reduced or optimal level.

[0020] It is a feature of the present invention that the application of desired additives to the reinforcing fiber with the sizing composition may result in a reduction in the amount of wasted additives and manufacturing costs.

Problems solved by technology

Although this process is generally suitable for forming large planar sheets, it is less suitable for forming composite products that have complex profiles and / or otherwise formed portions.

In addition, wood fiber and strand thickness and length typically utilized in producing OSB products are generally less suitable for products intended for applications in which mechanical forces must be transmitted more uniformly throughout the composite product.

Indeed, the variations in the diameter and length of the wood fibers incorporated into the OSB products tend to produce regions of high pressure and low pressure that render such products generally unsuitable for articles subjected to bending stresses.

The structural limitations associated with particleboard, particularly its reduced strength relative to corresponding thicknesses of OSB and plywood products, its tendency to absorb water, and its increased density render it unsuitable for many applications, particularly exposed applications or those in which significant loads are anticipated.

This limitation can result in an acute disadvantage in systems that obtain waste wood from many different sources.

The use of these isocyanate binding agents may also raise environmental and workplace safety issues.

These compositions also tend to exhibit only limited moisture protection and do not tend to exhibit uniform strength characteristics throughout their load bearing portions.

While the products produced by incorporating one or more plastics may exhibit improved moisture resistance, such articles continue to suffer from either the strength limitations referenced above or by requiring an intricate and complex forming process.

Additionally, the conventional methods which utilize wood fibers in some capacity to form a finished composite article do not tend to utilize the waste wood supply in any substantive manner, with portions of the waste wood typically being incinerated, used as fuel in an electrical cogeneration facility or buried in a landfill.

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