Skip to page content
USDA Forest Service
  
Treesearch

Research & Development Treesearch

 
Treesearch Home
About Treesearch
Contact Us
Research & Development
Forest Products Lab
International Institute of Tropical Forestry
Northern
Pacific Northwest
Pacific Southwest
Rocky Mountain
Southern Research Station
Help
 

Science.gov - We Participate


USA.gov  Government Made Easy


Global Forest Information Service

US Forest Service
P.O. Box 96090
Washington, D.C.
20090-6090

(202) 205-8333

You are here: Home / Search / Publication Information
Bookmark and Share

Publication Information

View PDF (309 KB bytes)

Title: Co-extrusion of WPCs with a clear cap layer to improve color stability

Author: Stark, Nicole M.; Matuana, Laurent M.;

Date: 2009

Source: Proceedings: 4th Wood Fibre Polymer Composites International Symposium: March 30-31, 2009, Bordeaux, France: conferences and exhibition. [Paris?] : FCBA Institut Technologique, 2009: pages 1-13.

Publication Series: Miscellaneous Publication

Description: Wood-plastic composites (WPCs) have been gaining market share in residential construction applications such as lumber for decking, roof tiles, and siding. The durability of these materials in exterior environments is just beginning to be understood. Current research suggests that controlling moisture absorption by the composite is key to improving durability. Methods to improve moisture resistance of WPCs have met with limited success. Co-extrusion involves the simultaneous extrusion of two dissimilar materials as a single profile. A previous study demonstrated that co-extrusion of a base WPC with a clear cap layer positively enhanced water sorption characteristics initially, but weathering cracked the cap layer and caused delamination. Therefore, we investigated co-extruding a stabilized high-density polyethylene (HDPE) cap layer with a base WPC consisting of 50% juniper wood flour, 44% HDPE and 6% lubricant. The HDPE cap layer included combinations of a compatibilizer, nano-TiO2, and a photostabilizer package. A 2[superscript]3 full factorial design was used to determine the formulations of the cap layer. Composite color was monitored and changes were calculated after weathering for 1000 hours in a xenon-arc weathering apparatus. The results suggest that either nano-TiO2 or a photostabilizer package can be used to prevent cap layer cracking and aid in color retention after weathering. However, statistical models developed suggest that there is a negative interaction when using the two together.

Keywords: Wood-plastic composites, polyethylene, color fading, composite materials, deterioration, weathering, accelerated life testing, wood flour, extrusion process, injection molding of plastics, ultraviolet radiation, composite materials, moisture, adsorption, absorption, metallic oxides, titanium, juniper, discoloration, wood-plastic materials, accelerated testing, HDPE, photostabilizers, durability, surface properties, ultraviolet absorber, moisture content

Publication Notes:

  • We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
  • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.

XML: View XML

Citation:


Stark, Nicole M.; Matuana, Laurent M. 2009. Co-Extrusion of WPCs with a clear cap layer to improve color stability. In: Proceedings of 4th wood fibre polymer composites international symposium. 30-31 March 2009. FCBA Institut Technologique. Bordeaux, FRANCE. (http://www.fpl.fs.fed.us/documnts/pdf2009/fpl_2009_stark001.pdf)

 


 [ Get Acrobat ]  Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

USDA logo which links to the department's national site. Forest Service logo which links to the agency's national site.