Introduction

Wood plastic composites (WPCs) can be described as composite products containing wood (in a variety of forms) mixed with thermoplastics or thermosets

Common Uses

Products made from WPCs have experienced tremendous growth in recent years, predominantly in the United States. In particular, WPCs have gained a significant share of the residential decking market, a trend due in part to the CCA ban. It is suggested that WPCs will command a greater share of the US decking market than softwoods by 2010. Additional residential products such as siding, fencing and roofing are also emerging

Four factors are thought to be responsible for the recent surge in the WPC residential market: the adverse effect of treating chemicals on the environment, effective marketing, the quality/cost ratio, and, perhaps most importantly, the acceptance of WPCs by builders. Demand for WPCs has also developed in the automotive industry for use in both interior and exterior components. The automotive industry considers WPCs to be a promising green material that may be able to achieve durability without the use of toxic preservatives

Opportunities in the Highway Sector There is a growing interest in ‘greening’ the US highway and road construction sector. Typically, this movement is led at the state level by the Department of Transportation (DOT). Government agencies in charge of highway construction in the US are showing interest in using more sustainable products and avoiding potentially harmful preservative-treated products

According to DOT officials, purchasing in the US highway construction sector can be the responsibility of two entities; the DOT itself, or the highway construction contractors hired by the DOT4 ; however, it is suggested that the majority of the purchasing for large construction projects is conducted by the contractors.

Regardless of the purchaser, any products used in highway or road applications must be approved and published in a Qualified Products List5 . These product lists are updated regularly and indicate that a product has been tested and found to be suitable for use in a specific category. To be included in a Qualified Products List, a product must undergo a series of testing which, depending on the product, can include the testing of impact effects, mechanical properties, color requirements, and durability.

Methods

Highway contractors in eight western states were sent questionnaires by mail. Potential respondents included contractors with ten or more employees. Estimates of sector wide purchasing were achieved based on a comparison of respondent employment and sector wide employment.

Questionnaires aimed to measure the following:

 Annual purchases of three test products (tubular markers, in-road reflectors, and guardrail posts)

 Familiarity with WPCs

Perceptions of WPCs in comparison to other materials

 importance of product attributes when purchasing

 Attributes used to measure product sustainability

Conclusions

WPCs will face four key challenges as manufactures attempt to penetrate the highway sector.

First, costs are clearly a priority. WPC manufacturers will have to reach a competitive price point in order to appeal to contractors in the sector.

Second, manufacturers will need to convince purchasing agents that the quality of WPC products is equal or superior to traditional products. Third, manufacturers must ensure that WPC products are readily available to highway contractors.

Fourth, and perhaps most important, WPC products engineered for highway applications must meet the rigorous testing requirements necessary to gain inclusion within a state-level qualified products list.

The differentiating qualities of WPCs (e.g. sustainability, locally made, etc) will not support entry into the highway product market. Competitive pricing, quality, availability, and DOT approval will be essential.