Search Results

You are looking at 1 - 6 of 6 items

  • Author: J. Simonsen x
Clear All Modify Search

Abstract

The effect of wood/plastic ratio and the presence of a boron compound on resistance to biodegradation of wood plastic composites (WPC's) by the brown rot fungus Gloeophyllum trabeum was investigated in a soil block exposure. Weight losses of all WPC's were generally lower than those of solid wood, even when only the wood component of the WPC was used in calculating weight loss. Higher wood content was associated with greater weight losses, suggesting that the plastic encapsulated wood at lower wood levels. Borates markedly reduced weight losses at all wood/plastic ratios. Weight losses tended to be slightly lower with a Na/Ca borate than with similar levels of zinc borate. Mechanical properties did not correlate well with weight losses under the conditions evaluated, but these effects may have been masked by moisture sorption. The causes and implications of these differences are discussed.

Abstract

Wood products with anti-electrostatic properties have wide applications in many fields. However, wood is an insulator and does not itself have anti-electrostatic ability. This study investigated several ionic liquids as anti-electrostatic agents for wood. Ionic liquids are liquids at room temperature (or close to room temperature), possess no vapor pressure and are excellent conductors for electric current. Maple and pine veneers were either soaked in or brushed with five ionic liquids: 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-butyl-3-methylimidazolium chloride, 1-ethyl-3-methylimidazolium tetrafluoroborate and 1-ethyl-3-methylimidazolium hexafluorophosphate. The ionic liquid-treated wood specimens were then measured for surface resistivity and volume resistivity in accordance with ASTM standards. The effects of application method (brushed vs. soaked) and storage time were investigated. All the ionic liquids studied were effective anti-electrostatic agents for pine and maple. For all ionic liquids tested, pine had lower resistivity, and thus higher anti-electrostatic ability, than maple.

Abstract

The leaching of toxins from treated wood poses an, as yet, poorly quantified risk to both plant and animal life. In particular, the leaching of pentachlorophenol (PCP) into rainwater falling on treated wood over aquatic environments, such as bridges, is understudied. Computer models have been developed which predict the leaching of creosote from marine pilings. If data were available, similar models could be developed for PCP-treated bridges and the risk to waterways determined for various structural designs. Providing such data is the objective of this study, where the migration of PCP from treated wood under the influence of simulated rainfall was studied using a simulation system that delivered uniform rainfall rates over-treated wood. The runoff from the treated wood was captured and analyzed with high resolution gas chromatography combined with low resolution mass spectrometry. PCP migrated from treated wood into rainwater runoff at a fairly constant rate of approximately 0.15 g l-1 m-2. Small non-significant deviations were observed with rainfall rate, time, and temperature. We suggest that PCP migration rates from exposed treated wood can be modeled and thereby predict the migration of PCP from this source into the environment.