Effect of Tie-Layer on the Bond Strength Between Thermoplastic and Borate-Treated Wood Substrate

Abstract

A challenge in using wood or wood composites for exterior applications is durability. Borate-treated wood substrates are durable if leaching of the chemical over time can be reduced to acceptable levels. The goal of this project was to encapsulate borate-treated structural wood and wood-based composites with thermoplastic to extend their durability. In this study, the efficacy of two tie-layers (maleic anhydride modified high-density polyethylene and styrene-butadiene polymer) in bonding high-density polyethylene (HDPE) to treated wood substrate was examined together with determining the ideal hot-press parameters necessary to achieve a good bond. Boric oxide treated Douglas-fir and southern pine Parallam® and untreated Douglas-fir solid wood were the substrates investigated. The optimum processing parameters were 180°C platen temperature, 1035 kPa press pressure, and 300 s press time. Bond strength was determined by conducting a 90° peel test and a block-shear test. Durability of the thermoplastic barrier layer was evaluated by subjecting specimens to an accelerated aging test and reevaluating the bond strength. Maleic anhydride-modified HDPE tie-layer yielded improved bond strength that was durable, especially when bonded to a treated southern pine substrate

Similar works

This paper was published in Wood and Fiber Science (E-Journal).

Having an issue?

Is data on this page outdated, violates copyrights or anything else? Report the problem now and we will take corresponding actions after reviewing your request.